METHOD AND APPARATUS FOR EFFECTING A PREDETERMINED TRANSFORMATION

Related Application The present application claims convention priority from Australian

Provisional Patent Application No. 2007901416, filed 19 March 2007, the content of which is herein incorporated by reference.

Field of the Invention The present invention relates to a method and apparatus for effecting a predetermined transformation such as a chemical reaction, or destroying a pathogen. More specifically, it relates to a method and apparatus for creating an active species in a reaction vessel and to means for delivering such active species to a fluid medium bearing an organic and/or pathogenic contaminant load. More specifically still, the present invention relates to a method and apparatus for achieving the above, with relatively greater energy efficiency.

The invention has been developed primarily as a means of remediating wastewater containing a load of small organic molecules such as the carcinogen 1,4-dioxane, and/or endocrine disrupting compounds such as N- nitrosodimethylamine (NDMA), and/or non-aesthetic compounds such as those emitting undesirable odour and/or colour, and/or pathogens/organisms such as bacteria, viruses and protozoa.

Although the present invention will be described herein with reference to applications such as those recited above, it will be appreciated that the invention is not limited to this particular field of use.

Background of the Invention

Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

In recent years, the treatment and remediation of secondary effluent for the purposes of re-use has become increasingly important. Factors such as generally increasing population pressures, urbanisation, global warming with the attendant

changes in weather patterns, and the continuing industrial pollution of natural sources of fresh water serve to place often severe limitations on the per capita availability of fresh drinking water. Accordingly, liquid-based effluent is becoming increasingly treated and re-used to both potable and non-potable standards.

Two of the principal contaminants of unpotable water are harmful or undesirable organic compounds (e.g. N-nitrosodimethylamine (νDMA) and 1,4- dioxane), and pathogens. A pathogen or infectious agent is a biological agent that causes disease or illness to its host. The term is most often used for agents that disrupt the normal physiology of a multicellular animal or plant. However, pathogens can infect unicellular organisms from all of the biological kingdoms. There are many substrates and pathways through which pathogens can invade a host; water contamination is amongst the highest potential sources for harbouring a pathogen. Some pathogens (e.g. the bacterium Yersinia pestis, to which the Black

Plague and Variola virus have each been attributed) have been found responsible for a significant number of fatalities. Of particular note in recent times are the protozoa Cryptosporidium and Giardia lamblia. Social advances such as food safety, hygiene, and water treatment have reduced the threat from some pathogens.

The past three decades has seen significant change in how secondary effluent is treated. Specifically, new filter and membrane technologies have supplemented and even replaced more traditional effluent treatments. In addition, new disinfection technologies have also evolved and been applied to supplement the improved membrane technologies.

The removal of certain organic contaminants from secondary effluent may be accomplished using advanced oxygenation processes (AOPs). In chemical terms, "photocatalysis" is the acceleration of a photoreaction in the presence of a catalyst. In catalysed photolysis, light is absorbed by an adsorbed substrate. In photogenerated catalysis the photo catalytic activity (PCA) depends on the ability of the catalyst to create electron hole pairs, which generate free radicals able to undergo secondary reactions. This is the essential theory upon which water electrolysis by means of titanium dioxide (TiO ₂ ) is based.

Although effective for the removal of organics, AOPs alone are unsuitable for the removal of pathogens. However, it has been found that pathogens may be effectively removed from a contaminated fluid through applying a secondary disinfection step. Disinfection, often termed "tertiary treatment" is generally the final step in water purification. Disinfection destroys any pathogens that pass through membrane filters or survive any preceding AOP/s. Such pathogens may include viruses, bacteria (e.g. Escherichia coli, Campylobacter and shigella), and protozoa (e.g. Giardia lamblia and Cryptosporidia). In most developed countries, public water supplies are required to maintain a residual disinfecting agent throughout the distribution system, in which water may remain for days before reaching the consumer.

The most common disinfection method uses some form of chlorine or its related compounds such as chloramine or chlorine dioxide. Chlorine dioxide is less commonly used because it may create excessive amounts of chlorate and chlorite, both of which are regulated to low allowable levels.

Chlorine is a strong oxidant that kills many microorganisms. However, a major drawback to using chlorine (or sodium hypochlorite, which releases chlorine) is that it reacts with organic compounds in the water to form potentially harmful levels of chemical by-products, such as trihalomethanes (THMs) and haloacetic acids (HAAs), both of which are carcinogenic and regulated by the US Environmental Protection Agency (USEPA). The formation of THMs and HAAs is minimised through effective removal of as many organics from the water as possible before disinfection. Although chlorine is effective in killing bacteria and viruses, it has limited effectiveness against protozoa that form cysts in water, (e.g. Giardia lamblia and Cryptosporidium).

Chloramines are another chlorine-based disinfectant. Although chloramines are generally not as effective as disinfectants, compared with chlorine gas or sodium hypochlorite, they are less prone to form THMs or haloacetic acids. It is possible to convert chlorine to chloramine by adding ammonia to the water along with the chlorine. Water distribution systems disinfected with chloramines may experience nitrification, wherein ammonia is used a nitrogen source for bacterial growth, with nitrates being generated as a by-product.

Ozone (O ₃ ) is a relatively unstable molecule that readily gives up one atom of oxygen providing a powerful oxidising agent toxic to many water-borne organisms. It is a strong, broad-spectrum disinfectant that is widely used throughout Europe as an effective agent in the destruction of harmful cyst-forming protozoa and almost all other pathogens. However, disinfecting ozone must be formed on-site and moreover, ozone can often lead to the formation of the carcinogenic by-product, bromate.

Ultra-violet (UV-C) radiation has been shown to be very effective at inactivating cysts and other pathogens, as long as the water has a relatively low level of colour such that the UV can pass through without being absorbed. The main drawback to the use of UV radiation is that it consumes relatively high levels of electrical power.

Historically, disinfection using UV radiation was more commonly used in wastewater treatment applications, but is finding increased usage in drinking water treatment. A process named SODIS has been researched extensively in Switzerland and proven ideal to treat small quantities of water. Contaminated water is filled into transparent plastic bottles and exposed to full sunlight for six hours. The sunlight in turn treats the contaminated water through two synergetic mechanisms: Radiation in the spectrum of UV-A (λ 320-400 nm) and increased water temperature. If the water temperature rises above around 50 °C, the disinfection process is around three times faster.

It was once thought that UV disinfection was more effective for bacteria and viruses, which have more exposed genetic material, than for larger pathogens which have outer coatings or that form cyst states (e.g. Giardid) that shield their DNA from the UV light. However, it was recently discovered that UV radiation can be effective for treating the microorganism Cryptosporidium. Such findings form the basis of US Patent No. 6,565,803, to Bolton, et ah, which relates to the use of UV radiation as a viable method with which to treat drinking water. Giardia, in turn, has proven susceptible to UV-C when tests are based on infectivity rather than excystation. It turns out that protists are able to survive high UV-C doses but are sterilised at low doses.

In the presence of certain molecules, such as ozone or hydrogen peroxide, UV radiation may give rise to potent active species such as hydroxyl radicals.

Having one unpaired electron, this free radical can break down organic molecules and even de-activate pathogens, especially when complimented with direct photolysis from the UV light at disinfection wavelengths, such as 254 run.

The present state of the art in the treatment of secondary effluent to potable standards typically includes a first-pass microfiltration or ultrafiltration process, thereby to remove physical or granular contaminants such as dirt or relatively large molecules. Such processes may also remove certain pathogens from the effluent. The first-pass micro -filtration or ultrafiltration process is typically followed by a Reverse Osmosis (RO) membrane treatment that also removes remaining pathogens, as well as smaller dissolved organic and inorganic molecules. Finally, a disinfection step and/or AOP/s may be present so as to remove any residual pathogens. Such a step typically utilises chlorine, ozone or UV light as the disinfectant, as related above.

Relatively recently, however, it has been shown that low concentrations of certain small organic molecules such as 1,4-dioxane and NDMA have the ability to pass through an RO treatment process or even form as by-products (e.g. THMs) from chemical disinfection treatments. Such molecules pose a significant health risk in that they are known carcinogens.

As related above, in photogenerated catalysis the photo catalytic activity (PCA) depends upon the ability of the catalyst to create electron hole pairs, which generate free radicals able to undergo secondary reactions. The resulting free radicals are very efficient oxidisers of organic matter. Photocatalytic activity in TiO ₂ has been studied extensively because of its potential use in sterilisation, sanitation, and remediation applications. TiO ₂ , when irradiated by UV, reacts with water and oxygen to form reactive species such as hydroxyl and superoxide free radical molecules. The photocatalytic activity of TiO ₂ results in thin coatings of the material exhibiting serf-cleansing and disinfecting properties under exposure to UV radiation. TiO ₂ is desirous as an agent in the remediation of contaminated water due to several factors, including, but not limited to: the process occurs under ambient conditions; TiO ₂ is not consumed or degraded; oxidation of organic molecule contaminants to water and CO ₂ can be effected to completion; the photo catalyst is inexpensive and has a high turnover; TiO ₂ can be supported or immobilised on suitable reactor

substrates; and the process offers great potential as an industrial technology to detoxify contaminated waters.

In order to remove organic contaminants, some treatment plants have installed UV-peroxide or UV-ozone AOP treatment facilities. In such facilities, peroxide is typically injected into the treated effluent stemming from the initial RO procedure, and this mix is then passed through a high flux of UV light. Appreciably, such facilities suffer from significant problems, primarily associated with cost and chemical exposure. Where a raw secondary effluent contains no organic load, the UV light required to disinfect such a stream is typically 40 mJ/cm /s or higher. Where such effluent does contain an organic load, peroxide is required to be added, and the peroxidised effluent is then passed through UV light with a flux of typically 150-500 mJ/cm ² /s. To achieve such UV intensity, a typical 100 ML/day treatment plant may require 200-250 UV lamps, each costing around US$2,000, and each needing to be replaced annually. In addition, the cost of electricity need to run such a UV source is appreciably vast.

United States Patent No. US 6,285,816, to Anderson, et ah, relates to a waveguide comprising a transparent substrate and a metal oxide coating. The substrate can propagate light in an attenuated total reflection mode. The claims define a waveguide for propagating light of a selected wavelength in an attenuated total reflection mode, the waveguide comprising: a transparent internal reflection element (IRE); and a particulate transition metal oxide coating on one or more surfaces of the internal reflection element, the coating having a boundary parallel to the at least one IRE surface, wherein the coating does not scatter light of the selected wavelength and has a refractive index greater than that of the internal reflection element.

The prior art arrangements, such as that disclosed by Anderson, above, typically suffer from efficiency problems in terms of how best one can deliver and active species (generally, UV light or hydroxyl/superoxide free radical molecules from TiO ₂ -induced photocatalysis of light) to the contaminated species undergoing remediation. To this end, the relatively inefficient systems disclosed in the prior art result in a relatively high cost per unit volume of remediated product. It will be appreciated that where, for instance, said remediated product is potable water for consumer sale, the net result of such a relatively inefficient

system is a product that cannot be priced competitively against competitor brands such as water bottled at source.

One of the principle factors influencing the efficiency of such a system is the means by which the active species is brought into contact with the contaminant species. Where the raw active species is, for instance, light, such media may be solid, liquid, gas, or combinations thereof. Indeed the three related patent applications referenced at p.l of the present document each relate to inventions wherein such media are adapted toward a relatively increased delivery efficiency of the active or excitable species. United States Patent No. US 5,069,885, to Ritchie, discloses an apparatus for the purification of a fluid, such as water, which in the presence of light of an activating wavelength brings the fluid into contact with surfaces with fixed photoreactive coatings of anatase (TiO ₂ ) or other photoreactive semiconductors, thereby detoxifying, reducing or removing organic pollutants therefrom. The apparatus includes a non-transparent substrate coiled longitudinally and helically around a transparent sleeve. The non-transparent substrate has photoreactive semiconductor material bonded thereto. The non-transparent substrate defines a helical path through an annular cylindrical housing.

The helical coil embodies no waveguiding properties such that it is a non- transparent material upon which TiO ₂ is coated. Moreover, the surface area to volume ratio of such an apparatus would be relatively inefficient, requiring relatively large energy consumption per unit end product.

United States Patent No's. US 5,790,934 and US 6,063,343, each to E. Heller & Company, discloses a compact, efficient reactor for the photocatalysed conversion of contaminants in a fluid stream. The reactor includes a photocatalyst disposed on a support structure with a light source in optical proximity to the support structure to activate the photocatalyst. In one embodiment of the invention, the support structure includes multiple non-intersecting fins oriented parallel to the general flow direction of the fluid stream to provide a reactor with low pressure drop and adequate mass transfer of the contaminant to the photocatalyst disposed on the surface of the fins. The light source includes one or more lamps that may penetrate the fins to provide efficient illumination of the photocatalyst.

United States Patent No. 6,108,476, to Iimura, relates to a photocatalyst optical fiber and a method for activating the photocatalyst optical fiber. The photocatalyst optical fiber comprises at least an optical fiber having a core and a light input end, a photocatalyst layer including photocatalyst disposed partially or entirely on the core, wherein light is introduced from the light input end into the core and the light reflects repeatedly inside of the core, wherein said light leaks gradually from the core to the photocatalyst layer, and wherein the photocatalyst layer is activated by irradiation of the light. The method for activating the photocatalyst optical fiber comprises: (a) providing at least an optical fiber, each having a photocatalyst layer, i.e. photocatalyst film including photocatalyst, in which the photocatalyst layer is partially or entirely disposed on the optical fiber; (b) introducing light into the optical fiber; (c) letting the light to reflect repeatedly inside of the optical fiber; and (d) letting the light to leak gradually from the optical fiber to the photocatalyst layer, whereby the photocatalyst layer is activated by irradiation of the light. Therefore, US 6,108,476 can efficiently activate the photocatalyst on the optical fiber by irradiating directly light leaked from the optical fiber. Unfortunately, the invention defined in US 6,108,476 is unsuitable for application in scale-up flow-through industrial processes.

United States Patent No. 6,238,630, also to Iimura, relates to a photocatalyst device including a light guide member composed of a substantially transparent member having a first surface and/or a second surface, a plurality of diffusing areas and a plurality of non-diffusing areas disposed alternately on the first surface and/or the second surface, and photocatalyst member including photocatalyst material, being disposed adjacent to the transparent member, or being disposed on the transparent member. Further, a photocatalyst reactor includes the photocatalyst device as described above and one or more light sources generating light directed toward the transparent member. The transparent member may be composed of a transparent panel having a substantially uniform thickness or a substantially variable thickness. A density of the diffusing areas and/or the non-diffusing areas may be variably distributed on the first surface and/or the second surface. The diffusing areas may be rough surface areas and/or the non-diffusing areas may be smooth surface areas. The invention defined in US 6,238,630 is unsuitable for efficient application in scale-up flow-through

industrial processes.

United States Patent No. 6,258,736, to Massholder discloses a device with at least one surface layer made from a semiconductor material having an inner side, which rests on a support, and a disinfectable and/or oxidising outer side, and with a UV radiation source, in which device the support conducts light, UV radiation from the UV radiation source is input directly on to the inner side of the semiconductor material via the light-conducting support. The light-conducting support and the surface layer of the semiconductor material lying thereon can be applied to the surface of a piece of equipment which is to be disinfected or may even form this piece of equipment. Although one may envisage such a device being amenable to a scale-up flow-through water treatment facility, the use of semiconductors render it undesirably complex and therefore, relatively expensive and undesirable.

United States Patent No. 6,764,655, to Nisliii, relates to a light-leakage type pliotocatalyst in which fibers are bundled together to form a filter assembly having an enormous number of minute gaps which provide fluid communication paths in a longitudinal direction of the photocatalyst fibers. Light is incident to each of the photocatalyst fibers constituting the filter assembly while an object fluid to be processed is introduced through an end face of the filter assembly to pass through the gaps among the photocatalyst fibers in the longitudinal direction.

However, the invention disclosed in US 6,764,655 is adapted for a single-pass flow through, which requires either a larger cell size, or successive cells arranged in series, in order to provide the sought UV exposure to the incident wastewater.

United States Patent Nos. 5,875,384 and 6,051,194, both to Peill, et al, each relate to a photochemical reactor system employing optical fibers in the form of a cable to transmit light to solid-supported TiO ₂ containing photocatalyst. Light energy is transmitted to TiO ₂ containing particles, chemically anchored onto one or more quartz fiber cores, via radial refraction of light out of each fiber. TiO ₂ containing coating layer minimises the interfacial surface area of the quartz core and TiO ₂ containing particles and operation with incident irradiation angles near 90 degrees enhance light propagation along the fibers. A maximum quantum efficiency of φ =1.1% for the oxidation of 4-chlorophenol was achieved. Fiber efficiency permits the light source to be separated from the photocatalyst. Neither

system is suitable for a scale-up flow-through industrial process aimed at treating organics-bearing secondary effluent.

United States Patent No. 6,555,011, to Tribelski, et ah, relates to a method for disinfecting and purifying liquids and gasses comprising: a) passing said liquids or gasses through a reactor or a combination of reactors, having a truncated compounded concentrator geometry; and b) simultaneously delivering and concentrating diversified electromagnetic and acoustic energies into a specific predetermined inner space of said compounded concentrator reactor, forming a high energy density zone in said reactor or reactors over a predetermined period of time. The reactor is preferably a compounded parabolic concentrator or a compounded ellipsoidal concentrator. The electromagnetic energy delivered and concentrated into and inside the reactor can be of any range of the electromagnetic spectrum, such as ultra-violet, visible, infra-red, microwave, etc., or combination thereof. The acoustic energy is of any suitable frequency. The radiation source delivering the electromagnetic radiation can be enclosed within the reactor or can be external to the reactor. The invention disclosed by US 6,555,011 is relatively complex, and thereby relatively expensive to build, operate and maintain.

United States Patent No. 6,773,609, to Hashizume, discloses a method for water treatment which comprises subjecting water containing a hazardous material such as a dioxin or polychlorinated biphenyls (PCBs) to an ozone treatment, contacting the water with fine bubbles of ozone having an average diameter of 0.5 to 3 microns, a combination of the ozone treatment with one or more of a hydrogen peroxide treatment, a UV radiation treatment, an electrolysis treatment and a treatment with a carbonaceous filter material. The above ozone treatment or combination of treatments can be used for surer realisation on of an intended effect of a water treatment, which is difficult to achieve by the use of a conventional method wherein ozone or hydrogen peroxide is simply mixed with a water to be treated. Electrolysis and ozonation techniques are relatively expensive, and the inventive method defined in Hashizume is therefore undesirable.

United States Patent No. 6,409,928, to Gonzalez, et ah, discloses a method and apparatus for mineralising organic contaminants in water or air. The invention provides photochemical oxidation in a two-phase or three-phase

boundary system formed in the pores of a TiO ₂ membrane in a photocatalytic reactor. In the three-phase system, gaseous (liquid) oxidant, liquid (gaseous) contaminant, and solid semiconductor photocatalyst meet and engage in an efficient oxidation reaction. The porous membrane has pores that have a region wherein the meniscus of the liquid varies from the molecular diameter of water to that of a capillary tube resulting in a diffusion layer that is several orders of magnitude smaller than the closest known reactors. The photocatalytic reactor operates effectively at ambient temperature and low pressures. A packed-bed photoreactor using photocatalyst-coated particles is also provided. The process defined in Gonzalez would be relatively expensive to operate, and labour- intensive to maintain.

United States Patent No. 6,932,947, to Leung, et al., discloses a fluid purification and disinfection system, which includes a housing, an ultraviolet lamp and a photocatalytic oxidation device. The housing is an enclosed case that is fitted with an inlet and an outlet; the ultraviolet lamp is mounted inside the housing; the photocatalytic oxidation device is a disinfection core coated with photocatalyst; the disinfection core is installed around the ultraviolet lamp, and is fixed onto said housing; the photocatalyst therein is titanium dioxide. The working principle of the invention is to utilise ultraviolet light to irradiate the titanium dioxide-coated surface of the photocatalytic oxidation device to generate the photocatalytic oxidation process. As a result, Escherichia coli, Vibriocholerae and pathogenic organisms that contact the surface of photocatalytic oxidation device can be relatively quickly killed, and contaminants in the fluid can be eliminated. By such means, water or fluid that flows through said disinfection device is disinfected and purified.

Japanese Patent No. 10-337579, to Kubota Corporation, relates to a process to remove by degradation trace poisonous materials such as polychlorinated dibenzodioxins (PCDDs), wherein water is passed through an ultraviolet ray reaction tower holding a photocatalyst which accelerates an oxidation reaction of the wastewater. The trace poisonous elements in the wastewater are removed by degradation with the photocatalyst and ultraviolet rays. In an ultraviolet and ozone reactor, wastewater containing poisonous materials flows into a reaction tower and flows upward together with a

photocatalyst. An ultraviolet ray is radiated from an ultraviolet lamp, and ozone is supplied from an ozone generator. The treated water near an outlet permeates a net, is conducted as ultraviolet and ozone treated water out to a pH-adjusting tank. The photocatalyst remaining with the net is circulated together with the surrounding treated water near to a flow inlet. During this time, it comes in contact with a powder photocatalyst in the reaction tower. Accordingly, the trace poisonous substances such are efficiently removed by degradation with synergism of the ultraviolet ray and the photocatalyst.

Japanese Patent No. 2003-144939, to Titanium Kogyo KK, relates to a substrate body for a photocatalyst having high photocatalytic activity and excellent fixing property to the substrate, and capable of being applied to both of gas and an aqueous solution. The substrate has effective separation/workability with a liquid to be treated such as contaminated water and capable of being borne for a practical use. The photocatalyst particle is fixed onto a surface of a granulation type artificial light weighted aggregate covered with a glass-based shell making an inorganic substance as a binder.

Japanese Patent No. 2003-190908, to Mitsubishi Jukogyo KK, relates to a treatment method and an apparatus capable of oxidising and decomposing sparingly decomposable substances existing in fly ashes. The treatment apparatus is intended for oxidising and decomposing sparingly decomposable substances contained in solid matter such as fly ashes discharged out of an incinerator. The apparatus comprises a mixing tank for mixing the solid matter with water and producing a slurry; and a decomposition tank where the sparingly decomposable substances contained in the slurry are oxidised and decomposed in the presence of hydroxyl radicals by intensely stirring the slurry. The decomposition tank is provided with pulverisation means for pulverising the solid matter, a plurality of catalyst-bearing beads that carry a photocatalyst or have photocatalytic function by themselves and are fluidised by contact with the slurry, and a UV lamp disposed in a position where UV rays are radiated to the catalyst-bearing beads. The hydroxyl radical is generated by the catalyst-bearing beads in combination with the UV lamp.

Japanese Patent No. 2001-327961, to Fujishima, relates to a water treating device capable of effectively treating dioxins in water and water to be treated

containing organic substances such as endocrine disrupting chemical materials, agricultural chemicals and organic colouring materials; the device uses an optical catalyst. A basket frame in which optical catalyst carrying reticulated sheets are horizontally placed is installed in a water tank into which the water to be treated flows. The whole of the basket frame is connected to the disk of a motor with a disk by a central shaft to be reciprocated vertically. Black light which is inserted into a glass tube is lit to make the optical catalyst generate hydroxyl radicals, and the amount of water coming into contact with the optical catalyst per unit time is relatively increased, thereby effectively decomposing the organic substances in the water to be treated at relatively high speed.

Japanese Patent No. 2002-018429, to Okada, relates to a water purifier in which dioxins, a chlorine compound, a nitric compound, a nitrogen oxide and an organic compound contained in drinking water such as tap water are subjected to oxidative decomposition treatment by a photocatalyst. Bacteria contained in drinking water are sterilised and more purified drinking water can be obtained. In a water purifier equipped with a cartridge removing dirt and chlorine contained in drinking water and an electrolytic water producer for changing drinking water into alkali ion water, a photocatalyst device for causing a catalytic action by irradiating ultraviolet rays on titanium dioxide is provided between the cartridge and the electrolytic water producer. Drinking water is passed through the photocatalyst device and bacteria contained in drinking water are sterilised by generated ozone. The ozone is then decomposed by the electrolytic water producer.

United States Patent Publication No. US 2006-0231470, to Hatch, et ah, relates to a cartridge for a water treatment system, effective to assist in the removal of contaminants by photo catalytic oxidation and by adsorption. The cartridge includes a plurality of stacked disks, preferably made of a UV light transmissive material, which disks define circuitous flow paths for water being treated. In a preferred embodiment, the disk surfaces contacted by the water are provided with a coating of a catalyst, such as TiO ₂ , activated by a UV light source positioned in the centre of the cartridge. The claims define an apparatus for treating a flow of water to facilitate the removal of contaminants therein, comprising: a pair of disks having complementary interfitting structure on opposite disk faces sized and positioned to define a flow chamber having a series

of concentric flow channels; inlet means for directing the flow of water to be treated into the outermost flow channel of the flow chamber; flow channel connecting means for directing the flow serially from the outermost flow channel into the next adjacent flow channel in a manner causing at least a portion of the flow of water to contact the flow channels along their full lengths; and, outlet means for directing treated water from the innermost flow channel of the flow chamber toward an outlet from the apparatus. There are inherent problems associated with positioning the light source within the cartridge by way of cost, convenience and design intricacy. It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

It is an object of the present invention in a particularly preferred form to provide a means of effecting a predetermined chemical transformation in a modular apparatus, that is relatively cheap to construct, maintain and operate. It is an object of a particularly preferred form of the present invention to provide means for remediating secondary effluent initially containing an organic load such as 1,4-dioxane and/or iV-nitrosodimethylamine (NDMA), preferably to a potable standard. It is a further object of the present invention, in a further preferred form, to provide a relatively cost effective means of achieving same. It is yet another object of the present invention in but another preferred form to provide means for delivering one or more active species to a reservoir or flow of a contaminated fluid. It is a further object of the present invention, in a further preferred form, to provide a relatively cost effective means of achieving same. Another object of an especially preferred form of the present invention is to provide a method and apparatus for remediating a flow or batch of contaminated material via photocatalytic and/or photolytic means.

By "transport medium" is intended to encompass any surface or substrate capable of propagating and emitting energy, specifically, UV light. Accordingly, included within the scope of "transport medium" is, for instance, a waveguide. Moreover, "waveguide", should not be held to its literal and technical definition, but rather, construed purposively within the broad definition of "transport medium" provided above. "Optical transporter" is intended synonymous with

"transport medium" and/or "waveguide".

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

Although the invention will be described with reference to specific examples it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Summary of the Invention

According to a first aspect of the present invention there is provided a method for delivering one or more active species to a reaction vessel, thereby to actively effect one or more predetermined transformations, said method comprising the steps of: providing a catalytic substrate; providing a feed to said reaction vessel, said feed comprising one or more predetermined reactants; providing an energy source wherein energy derived therefrom is contactable via a transport medium with said catalytic substrate, thereby to provide a species active against said one or more predetermined reactants; and contacting said active species with said feed, thereby to actively effect said predetermined transformation.

In an embodiment, said predetermined transformation takes place within a modular apparatus.

In an embodiment, said energy source is spaced from or proximal with said catalytic substrate. In another embodiment, said energy source is directly coupled with said catalytic substrate.

In an embodiment, said transport medium is a waveguide. Preferably, said waveguide is a planar optical waveguide. More preferably, said waveguide acts both as said transport medium and as a substrate for any catalytic material applied to the surface thereof.

In an embodiment, said waveguide comprises a single material. In another

embodiment, said waveguide comprises a plurality of materials. Preferably, said plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of said waveguide.

In an embodiment, said waveguide may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate incident light being shifted out of the plane of said waveguide and contacting with said catalyst.

In an embodiment, said catalytic material is applied to one or more surfaces of said catalytic substrate. In an embodiment, said catalytic material is illuminated substantially perpendicular to the axis thereof. In another embodiment, said catalytic material is illuminated substantially parallel to the axis thereof.

In an embodiment, said association of said catalytic substrate with said waveguide is such that said catalytic substrate is suspended within said waveguide.

In an embodiment, said catalytic substrate is dispersed within said feed. In such a preferred embodiment, the method preferably further comprises the step of retrieving and/or recycling said catalytic substrate from said remediated product.

In an embodiment, there is further provided an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. In another embodiment, there is further provided an outlet port integral with an inlet port, thereby to facilitate said method to operate on a batch basis.

In an embodiment, said feed is a fluid. Preferably, said fluid is a liquid, gas, or a combination thereof. More preferably still, said fluid is a fluid effluent, said method thereby operative to remediate at least a portion of said fluid effluent. More preferably still, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. More preferably yet, said liquid, gas and/or steam comprises said one or more predetermined reactants in solution and/or undissolved state. Most preferably, said liquid is water. In an embodiment, the solution comprises said one or more predetermined reactants in aqueous phase. Preferably, said contaminated or polluted liquid comprises one or more organic contaminants. More preferably still, said one or more organic contaminants comprise organic molecules, pathogens bacteria,

protozoa and/or viruses and/or other organisms. Preferably, said one or more organisms comprise bacteria, protozoa and/or viruses. Preferably, said organic molecules comprise 1,4-dioxane and/or N-mtrosodimethylamine (NDMA).

In an embodiment, said catalytic substrate is a photocatalytic substrate. Preferably, said photocatalytic substrate is TiO ₂ . More preferably, said TiO ₂ is coated to a uniform or non-uniform thickness of up to approximately 20 microns; preferably about 0.1 to 15 microns; most preferably about 0.1 to 5 microns.

In an embodiment, said energy is light. Preferably, said light comprises one or more wavelengths within the range of approximately 200-400 nm. In an embodiment, said active species is an excited species. Preferably, said excited species are free radicals.

In an embodiment, said catalytic material is provided as a coating over one or more surfaces of said waveguide. Preferably, said coating is adhered to said waveguide via solid phase, gas phase and/or liquid phase deposition techniques. More preferably, said deposition techniques comprise annealing, adhesive, etching, extrusion, moulding, dip coating, sputter coating, slot coating, lamination, or a combination thereof .

In an embodiment, said waveguide comprises a secondary surface component. Preferably, said secondary surface component is a laminate adhered to at least a portion of at least one surface of said waveguide. More preferably, said laminate renders advantageous mechanical strength characteristics.

In an embodiment, said coating may be on a substantially smooth or complex surface. Preferably, said waveguide has a complex surface. Preferably, said complex surface is applied upon said waveguide by etching, extrusion moulding, stamping, or a combination thereof.

In an embodiment, said complex surface is formed in the same material and is integral with said waveguide. In another embodiment, said complex surface is formed separately from said waveguide. In another embodiment, said complex surface is formed in a different material to said waveguide. In an embodiment, said complex surface facilitates enhanced fluid dynamics. Preferably, said enhanced fluid dynamics are relatively enhanced flow rate and/or relatively enhanced mixing.

In an embodiment, said complex surface increases the effective surface

area of said catalytic substrate.

In an embodiment, said waveguide comprises one or more stacked sheets.

Preferably, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface. Preferably, said one or more stacked sheets are arranged to provide optimal contact time of said feed with said active species.

In an embodiment, said one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume.

In an embodiment, said one or more stacked sheets are arranged to provide a serpentine flow of said feed between said sheets.

In an embodiment, said relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, said plate-and-frame type configuration comprises a plurality of said sheets stacked substantially horizontally. In an embodiment, said relatively increased surface area is enabled by way of a Swiss-roll type arrangement.

In an embodiment, said relatively increased surface area is enabled by way of a vane type arrangement.

In an embodiment, said waveguide comprises one or more stacked sheets/spaced plates, thereby to define a channel therebetween through which incident energy derived from said energy source is communicable with said one or more predetermined chemical reactants. Preferably, said channel comprises one or more gases. In another embodiment, said channel comprises one or more fluid materials. Preferably, said one or more fluid materials comprise mineral oil/s and/or fluorinated siloxanes.

In an embodiment, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface.

According to a second aspect of the present invention there is provided a method for delivering one or more active species to a reaction vessel, thereby to actively effect one or more predetermined transformations, said method comprising the steps of: providing a catalytic substrate;

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providing a feed to said reaction vessel, said feed comprising one or more predetermined reactants; providing an energy source wherein at least some incident energy derived therefrom is contactable via a transport medium with said catalytic substrate, thereby to provide at least a first species active against said one or more predetermined reactants; contacting said first species with said feed, thereby to actively effect at least one said predetermined transformation; and wherein said transport medium is also directly communicable between said reaction vessel and said energy source, thereby to contact at least some said incident energy with said one or more predetermined reactants and actively alternatively effect at least another said predetermined transformation. In an embodiment, said predetermined transformation takes place within a modular apparatus.

In an embodiment, said energy source is spaced from or proximal with said catalytic substrate. In another embodiment, said energy source is directly coupled with said catalytic substrate.

In an embodiment, said transport medium is a waveguide. Preferably, said waveguide is a planar optical waveguide. More preferably, said waveguide acts both as said transport medium and as a substrate for any catalytic material applied to the surface thereof.

In an embodiment, said waveguide comprises a single material. In another embodiment, said waveguide comprises a plurality of materials. Preferably, said plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of said waveguide.

In an embodiment, said waveguide may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate incident light being shifted out of the plane of said waveguide and contacting with said catalyst.

In an embodiment, said catalytic material is applied to one or more surfaces of said catalytic substrate.

In an embodiment, said catalytic material is illuminated substantially

"

perpendicular to the axis thereof. In another embodiment, said catalytic material is illuminated substantially parallel to the axis thereof.

In an embodiment, said association of said catalytic substrate with said waveguide is such that said catalytic substrate is suspended within said waveguide.

In an embodiment, said catalytic substrate is dispersed within said feed. In such a preferred embodiment, the method preferably further comprises the step of retrieving and/or recycling said catalytic substrate from said remediated product.

In an embodiment, there is further provided an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. In another embodiment, there is further provided an outlet port integral with an inlet port, thereby to facilitate said method to operate on a batch basis.

In an embodiment, said feed is a fluid. Preferably, said fluid is a liquid, gas, or a combination thereof. More preferably still, said fluid is a fluid effluent, said method thereby operative to remediate at least a portion of said fluid effluent. More preferably still, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. More preferably yet, said liquid, gas and/or steam comprises said one or more predetermined reactants in solution and/or undissolved state. Most preferably, said liquid is water. In an embodiment, the solution comprises said one or more predetermined reactants in aqueous phase. Preferably, said contaminated or polluted liquid comprises one or more organic contaminants. More preferably still, said one or more organic contaminants comprise organic molecules, pathogens bacteria, protozoa and/or viruses and/or other organisms. Preferably, said one or more organisms comprise bacteria, protozoa and/or viruses. Preferably, said organic molecules comprise 1,4-dioxane and/or iV-nitrosodimethylamine (NDMA).

In an embodiment, said catalytic substrate is a photocatalytic substrate. Preferably, said photocatalytic substrate is TiO ₂ . More preferably, said TiO ₂ is coated to a uniform or non-uniform thickness of up to approximately 20 microns; preferably about 0.1 to 15 microns; most preferably about 0.1 to 5 microns.

In an embodiment, said energy is light. Preferably, said light comprises one or more wavelengths within the range of approximately 200-400 nm.

In an embodiment, said active species is an excited species. Preferably,

said excited species are free radicals.

In an embodiment, said catalytic material is provided as a coating over one or more surfaces of said waveguide. Preferably, said coating is adhered to said waveguide via solid phase, gas phase and/or liquid phase deposition techniques. More preferably, said deposition techniques comprise annealing, adhesive, etching, extrusion, moulding, dip coating, sputter coating, slot coating, lamination, or a combination thereof .

In an embodiment, said waveguide comprises a secondary surface component. Preferably, said secondary surface component is a laminate adhered to at least a portion of at least one surface of said waveguide. More preferably, said laminate renders advantageous mechanical strength characteristics.

In an embodiment, said coating may be on a substantially smooth or complex surface. Preferably, said waveguide has a complex surface. Preferably, said complex surface is applied upon said waveguide by etching, extrusion moulding, stamping, or a combination thereof.

In an embodiment, said complex surface is formed in the same material and is integral with said waveguide. In another embodiment, said complex surface is formed separately from said waveguide. In another embodiment, said complex surface is formed in a different material to said waveguide. In an embodiment, said complex surface facilitates enhanced fluid dynamics. Preferably, said enhanced fluid dynamics are relatively enhanced flow rate and/or relatively enhanced mixing.

In an embodiment, said complex surface increases the effective surface area of said catalytic substrate. In an embodiment, said waveguide comprises one or more stacked sheets.

Preferably, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface. Preferably, said one or more stacked sheets are arranged to provide optimal contact time of said feed with said active species. In an embodiment, said one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume.

In an embodiment, said one or more stacked sheets are arranged to provide a serpentine flow of said feed between said sheets.

In an embodiment, said relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, said plate-and-fϊame type configuration comprises a plurality of said sheets stacked substantially horizontally. In an embodiment, said relatively increased surface area is enabled by way of a Swiss-roll type arrangement.

In an embodiment, said relatively increased surface area is enabled by way of a vane type arrangement.

In an embodiment, said waveguide comprises one or more stacked sheets/spaced plates, thereby to define a channel therebetween through which incident energy derived from said energy source is communicable with said one or more predetermined chemical reactants. Preferably, said channel comprises one or more gases. In another embodiment, said channel comprises one or more fluid materials. Preferably, said one or more fluid materials comprise mineral oil/s and/or fluorinated siloxanes.

In an embodiment, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface.

According to a third aspect of the present invention there is provided a method for delivering one or more active species to a reaction vessel, thereby to actively effect one or more predetermined transformations, said method comprising the steps of: providing a feed to said reaction vessel, said feed comprising one or more predetermined reactants; providing an energy source, thereby to produce incident energy therefrom; providing a transport medium communicable between said reaction vessel and said energy source, thereby to contact said incident energy with said one or more predetermined reactants and actively effect said predetermined transformation to give a remediated product.

In an embodiment, said predetermined transformation takes place within a modular apparatus.

In an embodiment, said transport medium is a waveguide. Preferably, said waveguide is a planar optical waveguide. More preferably, said waveguide acts both as said transport medium and as a substrate for any catalytic material applied to the surface thereof. In an embodiment, said waveguide comprises a single material. In another embodiment, said waveguide comprises a plurality of materials. Preferably, said plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of said waveguide.

In an embodiment, said waveguide may comprise scattering centres, reflective elements, difrractive elements, or a combination thereof, thereby to facilitate incident light being shifted out of the plane of said waveguide and contacting with said catalyst.

In an embodiment, there is further provided an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. In another embodiment, there is further provided an outlet port integral with an inlet port, thereby to facilitate said method to operate on a batch basis.

In an embodiment, said feed is a fluid. Preferably, said fluid is a liquid, gas, or a combination thereof. More preferably still, said fluid is a fluid effluent, said method thereby operative to remediate at least a portion of said fluid effluent. More preferably still, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. More preferably yet, said liquid, gas and/or steam comprises said one or more predetermined reactants in solution and/or undissolved state. Most preferably, said liquid is water.

In an embodiment, the solution comprises said one or more predetermined reactants in aqueous phase. Preferably, said contaminated or polluted liquid comprises one or more organic contaminants. More preferably still, said one or more organic contaminants comprise organic molecules, pathogens bacteria, protozoa and/or viruses and/or other organisms. Preferably, said one or more organisms comprise bacteria, protozoa and/or viruses. Preferably, said organic molecules comprise 1,4-dioxane and/or iV-nitrosodimethylamine (NDMA).

In an embodiment, said energy is light. Preferably, said light comprises one or more wavelengths within the range of approximately 200-400 nm.

In an embodiment, said active species is an excited species. Preferably,

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said excited species are free radicals.

In an embodiment, said waveguide comprises a secondary surface component. Preferably, said secondary surface component is a laminate adhered to at least a portion of at least one surface of said waveguide. More preferably, said laminate renders advantageous mechanical strength characteristics.

In an embodiment, said coating may be on a substantially smooth or complex surface. Preferably, said waveguide has a complex surface. Preferably, said complex surface is applied upon said waveguide by etching, extrusion moulding, stamping, or a combination thereof. In an embodiment, said complex surface is formed in the same material and is integral with said waveguide. In another embodiment, said complex surface is formed separately from said waveguide. In another embodiment, said complex surface is formed in a different material to said waveguide.

In an embodiment, said complex surface facilitates enhanced fluid dynamics. Preferably, said enhanced fluid dynamics are relatively enhanced flow rate and/or relatively enhanced mixing.

In an embodiment, said waveguide comprises one or more stacked sheets.

Preferably, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface. Preferably, said one or more stacked sheets are arranged to provide optimal contact time of said feed with said active species.

In an embodiment, said one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume.

In an embodiment, said one or more stacked sheets are arranged to provide a serpentine flow of said feed between said sheets.

In an embodiment, said relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, said plate-and-frame type configuration comprises a plurality of said sheets stacked substantially horizontally. In an embodiment, said relatively increased surface area is enabled by way of a Swiss-roll type arrangement.

In an embodiment, said relatively increased surface area is enabled by way of a vane type arrangement.

In an embodiment, said waveguide comprises one or more stacked sheets/spaced plates, thereby to define a channel therebetween through which incident energy derived from said energy source is communicable with said one or more predetermined chemical reactants. Preferably, said channel comprises one or more gases. In another embodiment, said channel comprises one or more fluid materials. Preferably, said one or more fluid materials comprise mineral oil/s and/or fluorinated siloxanes.

In an embodiment, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface.

According to a fourth aspect of the present invention there is provided an apparatus for delivering one or more active species to a reaction vessel, thereby to actively effect one or more predetermined transformations, said apparatus comprising: a catalytic substrate; means for providing a feed to said reaction vessel, said feed comprising one or more predetermined reactants; an energy source wherein energy derived therefrom is contactable via a transport medium with said catalytic substrate, thereby to provide a species active against said one or more predetermined reactants; and means for contacting said active species with said feed, thereby to actively effect said predetermined transformation. In an embodiment, said predetermined transformation takes place within a modular apparatus.

In an embodiment, said energy source is spaced from or proximal with said catalytic substrate. In another embodiment, said energy source is directly coupled with said catalytic substrate.

In an embodiment, said transport medium is a waveguide. Preferably, said waveguide is a planar optical waveguide. More preferably, said waveguide acts both as said transport medium and as a substrate for any catalytic material applied to the surface thereof.

In an embodiment, said waveguide comprises a single material. In another

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embodiment, said waveguide comprises a plurality of materials. Preferably, said plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of said waveguide.

In an embodiment, said waveguide may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate incident light being shϋted out of the plane of said waveguide and contacting with said catalyst.

In an embodiment, said catalytic material is applied to one or more surfaces of said catalytic substrate. In an embodiment, said catalytic material is illuminated substantially perpendicular to the axis thereof. In another embodiment, said catalytic material is illuminated substantially parallel to the axis thereof.

In an embodiment, said association of said catalytic substrate with said waveguide is such that said catalytic substrate is suspended within said waveguide.

In an embodiment, said catalytic substrate is dispersed within said feed. In such a preferred embodiment, the apparatus preferably further comprises means for retrieving and/or recycling said catalytic substrate from said remediated product. In an embodiment, there is further provided an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. In another embodiment, there is further provided an outlet port integral with an inlet port, thereby to facilitate said method to operate on a batch basis.

In an embodiment, said feed is a fluid. Preferably, said fluid is a liquid, gas, or a combination thereof. More preferably still, said fluid is a fluid effluent, said method thereby operative to remediate at least a portion of said fluid effluent.

More preferably still, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. More preferably yet, said liquid, gas and/or steam comprises said one or more predetermined reactants in solution and/or undissolved state. Most preferably, said liquid is water.

In an embodiment, the solution comprises said one or more predetermined reactants in aqueous phase. Preferably, said contaminated or polluted liquid comprises one or more organic contaminants. More preferably still, said one or

more organic contaminants comprise organic molecules, pathogens bacteria, protozoa and/or viruses and/or other organisms. Preferably, said one or more organisms comprise bacteria, protozoa and/or viruses. Preferably, said organic molecules comprise 1,4-dioxane and/or N-nitrosodimethylamine (NDMA). In an embodiment, said catalytic substrate is a photocatalytic substrate.

Preferably, said photocatalytic substrate is TiO ₂ . More preferably, said TiO ₂ is coated to a uniform or non-uniform thickness of up to approximately 20 microns; preferably about 0.1 to 15 microns; most preferably about 0.1 to 5 microns.

In an embodiment, said energy is light. Preferably, said light comprises one or more wavelengths within the range of approximately 200-400 nm.

In an embodiment, said active species is an excited species. Preferably, said excited species are free radicals.

In an embodiment, said catalytic material is provided as a coating over one or more surfaces of said waveguide. Preferably, said coating is adhered to said waveguide via solid phase, gas phase and/or liquid phase deposition techniques. More preferably, said deposition techniques comprise annealing, adhesive, etching, extrusion, moulding, dip coating, sputter coating, slot coating, lamination, or a combination thereof .

In an embodiment, said waveguide comprises a secondary surface component. Preferably, said secondary surface component is a laminate adhered to at least a portion of at least one surface of said waveguide. More preferably, said laminate renders advantageous mechanical strength characteristics.

In an embodiment, said coating may be on a substantially smooth or complex surface. Preferably, said waveguide has a complex surface. Preferably, said complex surface is applied upon said waveguide by etching, extrusion moulding, stamping, or a combination thereof.

In an embodiment, said complex surface is formed in the same material and is integral with said waveguide. In another embodiment, said complex surface is formed separately from said waveguide. In another embodiment, said complex surface is formed in a different material to said waveguide.

In an embodiment, said complex surface facilitates enhanced fluid dynamics. Preferably, said enhanced fluid dynamics are relatively enhanced flow rate and/or relatively enhanced mixing.

In an embodiment, said complex surface increases the effective surface area of said catalytic substrate.

In an embodiment, said waveguide comprises one or more stacked sheets.

Preferably, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface. Preferably, said one or more stacked sheets are arranged to provide optimal contact time of said feed with said active species.

In an embodiment, said one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume. In an embodiment, said one or more stacked sheets are arranged to provide a serpentine flow of said feed between said sheets.

In an embodiment, said relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, said plate-and-frame type configuration comprises a plurality of said sheets stacked substantially horizontally.

In an embodiment, said relatively increased surface area is enabled by way of a Swiss-roll type arrangement.

In an embodiment, said relatively increased surface area is enabled by way of a vane type arrangement. In an embodiment, said waveguide comprises one or more stacked sheets/spaced plates, thereby to define a channel therebetween through which incident energy derived from said energy source is communicable with said one or more predetermined chemical reactants. Preferably, said channel comprises one or more gases. In another embodiment, said channel comprises one or more fluid materials. Preferably, said one or more fluid materials comprise mineral oil/s and/or fluoridated siloxanes.

In an embodiment, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface.

According to a fifth aspect of the present invention there is provided an apparatus for delivering one or more active species to a reaction vessel, thereby to actively effect one or more predetermined transformations, said apparatus comprising:

a catalytic substrate; means for providing a feed to said reaction vessel, said feed comprising one or more predetermined reactants; means for providing an energy source wherein at least some incident energy derived therefrom is contactable via a transport medium with said catalytic substrate, thereby to provide at least a first species active against said one or more predetermined reactants; means for contacting said first species with said feed, thereby to actively effect at least one said predetermined transformation; and wherein said transport medium is also directly communicable between said reaction vessel and said energy source, thereby to contact at least some said incident energy with said one or more predetermined reactants and actively alternatively effect at least another said predetermined transformation. In an embodiment, said predetermined transformation takes place within a modular apparatus.

In an embodiment, said energy source is spaced from or proximal with said catalytic substrate. In another embodiment, said energy source is directly coupled with said catalytic substrate.

In an embodiment, said transport medium is a waveguide. Preferably, said waveguide is a planar optical waveguide. More preferably, said waveguide acts both as said transport medium and as a substrate for any catalytic material applied to the surface thereof.

In an embodiment, said waveguide comprises a single material. In another embodiment, said waveguide comprises a plurality of materials. Preferably, said plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of said waveguide. In an embodiment, said waveguide may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate incident light being shifted out of the plane of said waveguide and contacting with said catalyst.

In an embodiment, said catalytic material is applied to one or more surfaces of said catalytic substrate.

In an embodiment, said catalytic material is illuminated substantially perpendicular to the axis thereof. In another embodiment, said catalytic material is illuminated substantially parallel to the axis thereof.

In an embodiment, said association of said catalytic substrate with said waveguide is such that said catalytic substrate is suspended within said waveguide.

In an embodiment, said catalytic substrate is dispersed within said feed. In such a preferred embodiment, the apparatus preferably further comprises means for retrieving and/or recycling said catalytic substrate from said remediated product.

In an embodiment, there is further provided an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. In another embodiment, there is further provided an outlet port integral with an inlet port, thereby to facilitate said method to operate on a batch basis.

In an embodiment, said feed is a fluid. Preferably, said fluid is a liquid, gas, or a combination thereof. More preferably still, said fluid is a fluid effluent, said method thereby operative to remediate at least a portion of said fluid effluent. More preferably still, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. More preferably yet, said liquid, gas and/or steam comprises said one or more predetermined reactants in solution and/or undissolved state. Most preferably, said liquid is water.

In an embodiment, the solution comprises said one or more predetermined reactants in aqueous phase. Preferably, said contaminated or polluted liquid comprises one or more organic contaminants. More preferably still, said one or more organic contaminants comprise organic molecules, pathogens bacteria, protozoa and/or viruses and/or other organisms. Preferably, said one or more organisms comprise bacteria, protozoa and/or viruses. Preferably, said organic molecules comprise 1,4-dioxane and/or N-nitrosodimethylamine (νDMA).

In an embodiment, said catalytic substrate is a photo catalytic substrate. Preferably, said photo catalytic substrate is TiO ₂ . More preferably, said TiO ₂ is coated to a uniform or non-uniform thickness of up to approximately 20 microns;

preferably about 0.1 to 15 microns; most preferably about 0.1 to 5 microns.

In an embodiment, said energy is light. Preferably, said light comprises one or more wavelengths within the range of approximately 200-400 nm.

In an embodiment, said active species is an excited species. Preferably, said excited species are free radicals.

In an embodiment, said catalytic material is provided as a coating over one or more surfaces of said waveguide. Preferably, said coating is adhered to said waveguide via solid phase, gas phase and/or liquid phase deposition techniques. More preferably, said deposition techniques comprise annealing, adhesive, etching, extrusion, moulding, dip coating, sputter coating, slot coating, lamination, or a combination thereof .

In an embodiment, said waveguide comprises a secondary surface component. Preferably, said secondary surface component is a laminate adhered to at least a portion of at least one surface of said waveguide. More preferably, said laminate renders advantageous mechanical strength characteristics.

In an embodiment, said coating may be on a substantially smooth or complex surface. Preferably, said waveguide has a complex surface. Preferably, said complex surface is applied upon said waveguide by etching, extrusion moulding, stamping, or a combination thereof. In an embodiment, said complex surface is formed in the same material and is integral with said waveguide. In another embodiment, said complex surface is formed separately from said waveguide. In another embodiment, said complex surface is formed in a different material to said waveguide.

In an embodiment, said complex surface facilitates enhanced fluid dynamics. Preferably, said enhanced fluid dynamics are relatively enhanced flow rate and/or relatively enhanced mixing.

In an embodiment, said complex surface increases the effective surface area of said catalytic substrate.

In an embodiment, said waveguide comprises one or more stacked sheets. Preferably, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface. Preferably, said one or more stacked sheets are arranged to provide optimal contact time of said feed with said active species.

In an embodiment, said one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume.

In an embodiment, said one or more stacked sheets are arranged to provide a serpentine flow of said feed between said sheets. In an embodiment, said relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, said plate-and-frame type configuration comprises a plurality of said sheets stacked substantially horizontally.

In an embodiment, said relatively increased surface area is enabled by way of a Swiss-roll type arrangement.

In an embodiment, said relatively increased surface area is enabled by way of a vane type arrangement.

In an embodiment, said waveguide comprises one or more stacked sheets/spaced plates, thereby to define a channel therebetween through which incident energy derived from said energy source is communicable with said one or more predetermined chemical reactants. Preferably, said channel comprises one or more gases. In another embodiment, said channel comprises one or more fluid materials. Preferably, said one or more fluid materials comprise mineral oil/s and/or fluorinated siloxanes. In an embodiment, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface.

According to a sixth aspect of the present invention there is provided an apparatus for delivering one or more active species to a reaction vessel, thereby to actively effect one or more predetermined transformations, said apparatus comprising: means for providing a feed to said reaction vessel, said feed comprising one or more predetermined reactants; means for providing an energy source, thereby to produce incident energy therefrom; means for providing a transport medium communicable between said reaction vessel and said energy source, thereby to contact said incident energy with said one or more predetermined

reactants and actively effect said predetermined transformation to give a remediated product.

In an embodiment, said predetermined transformation takes place within a modular apparatus. In an embodiment, said transport medium is a waveguide. Preferably, said waveguide is a planar optical waveguide. More preferably, said waveguide acts both as said transport medium and as a substrate for any catalytic material applied to the surface thereof.

In an embodiment, said waveguide comprises a single material. In another embodiment, said waveguide comprises a plurality of materials. Preferably, said plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of said waveguide.

In an embodiment, said waveguide may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate incident light being shifted out of the plane of said waveguide and contacting with said catalyst.

In an embodiment, there is further provided an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. In another embodiment, there is further provided an outlet port integral with an inlet port, thereby to facilitate said method to operate on a batch basis.

In an embodiment, said feed is a fluid. Preferably, said fluid is a liquid, gas, or a combination thereof. More preferably still, said fluid is a fluid effluent, said method thereby operative to remediate at least a portion of said fluid effluent. More preferably still, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. More preferably yet, said liquid, gas and/or steam comprises said one or more predetermined reactants in solution and/or undissolved state. Most preferably, said liquid is water.

In an embodiment, the solution comprises said one or more predetermined reactants in aqueous phase. Preferably, said contaminated or polluted liquid comprises one or more organic contaminants. More preferably still, said one or more organic contaminants comprise organic molecules, pathogens bacteria, protozoa and/or viruses and/or other organisms. Preferably, said one or more organisms comprise bacteria, protozoa and/or viruses. Preferably, said organic

_

molecules comprise 1,4-dioxane and/or iV-iiitrosodimethylamine (NDMA).

In an embodiment, said energy is light. Preferably, said light comprises one or more wavelengths within the range of approximately 200-400 nm.

In an embodiment, said active species is an excited species. Preferably, said excited species are free radicals.

In an embodiment, said waveguide comprises a secondary surface component. Preferably, said secondary surface component is a laminate adhered to at least a portion of at least one surface of said waveguide. More preferably, said laminate renders advantageous mechanical strength characteristics. In an embodiment, said coating may be on a substantially smooth or complex surface. Preferably, said waveguide has a complex surface. Preferably, said complex surface is applied upon said waveguide by etching, extrusion moulding, stamping, or a combination thereof.

In an embodiment, said complex surface is formed in the same material and is integral with said waveguide. In another embodiment, said complex surface is formed separately from said waveguide. In another embodiment, said complex surface is formed in a different material to said waveguide.

In an embodiment, said complex surface facilitates enhanced fluid dynamics. Preferably, said enhanced fluid dynamics are relatively enhanced flow rate and/or relatively enhanced mixing.

In an embodiment, said waveguide comprises one or more stacked sheets.

Preferably, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface. Preferably, said one or more stacked sheets are arranged to provide optimal contact time of said feed with said active species.

In an embodiment, said one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume.

In an embodiment, said one or more stacked sheets are arranged to provide a serpentine flow of said feed between said sheets. In an embodiment, said relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, said plate-and-frame type configuration comprises a plurality of said sheets stacked substantially horizontally.

In an embodiment, said relatively increased surface area is enabled by way of a Swiss-roll type arrangement.

In an embodiment, said relatively increased surface area is enabled by way of a vane type arrangement. In an embodiment, said waveguide comprises one or more stacked sheets/spaced plates, thereby to define a channel therebetween through which incident energy derived from said energy source is communicable with said one or more predetermined chemical reactants. Preferably, said channel comprises one or more gases. In another embodiment, said channel comprises one or more fluid materials. Preferably, said one or more fluid materials comprise mineral oil/s and/or fluorinated siloxanes.

In an embodiment, said one or more stacked sheets are spaced by one or more discrete spacer units and/or said complex surface.

According to a seventh aspect of the present invention there is provided a waveguide comprising: two spaced plates defining a cavity therebetween, wherein said cavity is substantially populated with one or more fluid media, and wherein said cavity is associable with an energy source, such that the propagation of incident energy derived therefrom within said cavity is manipulable.

According to an eighth aspect of the present invention there is provided a waveguide comprising: two spaced substantially parallel plates unbounded along at least one edge and defining a cavity therebetween, wherein said at least one unbounded edge is associable with an energy source, and wherein said cavity is substantially filled with one or more fluid media such that the propagation of incident energy derived from said energy source within said waveguide is manipulable.

According to a ninth aspect of the present invention there is provided the product of a predetermined transformation, when said transformation is effected

by delivering one or more active species to a reaction vessel by a method according to any one of the first, second or third aspects of the present invention.

In general terms, the present invention provides means suitable for the treatment of organics-containing Reverse Osmosis effluent, such that the organics are removed with relatively high efficiency. The inventive process is scalable to a treatment plant that is desirably of relatively low capex.

A first mode of the inventive process is to use photocatalytic processes to create free radicals in effluent fluid (preferably water). It is known that UV light, when interacting with certain materials (such as TiO ₂ ) causes a photoreaction that initiates the decomposition of water into free radicals such as hydroxyl radicals (OH). These radicals are the active agent that reacts with the organic molecules in the effluent to initiate their decomposition into harmless products (most advantageously water and carbon dioxide). Whilst other inventors have sought to use such radical-based photocatalysts in the treatment of water, it has proved difficult to develop a system where the light required to initiate the sought photochemistry is efficiently brought to the catalytic material such as TiO ₂ . To this end, the principal limitations include: Firstly, since water, itself absorbs UV light, it is preferential that the light itself comes into contact the photocatalyst without first travelling through water. This will ensure efficient use of the UV light energy. The literature surveyed above appears to teach away from such an arrangement in proposing the use of TiO ₂ sols suspended in water, or even a TiO ₂ carrier system. However, each of these arrangements suffer from the problem of requiring light to pass through water in order to reach the TiO ₂ , and the attendant inefficiencies associated therewith.

Secondly, it has proven difficult to efficiently place the TiO ₂ in such a photochemical system. Known techniques include placing the TiO ₂ in a suspension, with the appreciably negative impact that the suspension itself limits the path-length of UV light through the solution due to light scattering. Further, such a TiO ₂ suspension is difficult to manage and maintain in a flow-through system. The alternative, as proposed according to the present invention, is to

affix the TiO ₂ on a surface somewhere within the system such that it is accessible to the UV light, and whereby the UV light does not have to travel through water in order to arrive at the TiO ₂ .

Thirdly, a further problem is that the radicals produced by photooxidation have a high propensity to recombine to form non-radical species, which are non- reactive. Hence, there is an optimum volume of water around the photooxidation site that ensures chemical oxidation of the effluent organic species is most efficiently effected. To this end, it will be apparent to those skilled in the art that the oxidative processes applicable to the present invention include electron hole, electron, hydroxyl radical and super oxide free radical processes.

In certain preferred embodiments, it may be preferable to add further oxygen to the system so as to prevent electron recombination. Accordingly, it is necessary for oxygen to be at least present in the photocatalytic reaction. This requirement may encompass the "normal" levels of oxygen in the water, but may also require that an additional available oxygen source is used; this latter option may have added cost implications.

Fourthly, yet a further problem arises in considering precisely how to get the UV light into a water-based system. For example, if the water passes through an optically clear pipe, the water can be irradiated with UV light. However, because light is absorbed by water and also because radicals can recombine, there is an optimum (and, incidentally, relatively short path-length) for the UV light applicable to this invention. Any macro-scale pipe is far from the optimum in terms of the ratio of irradiated surface area to water flow volume.

From the above discussion, it is clear that the three key features in any such system of remediating organics-containing effluent are: water, light and photocatalytic material. The present invention seeks to combine these in a manner which provides for a relatively simple and efficient remediation of such secondary effluent to both potable and non-potable standards.

Such a system is designed to relatively maximise the efficiency at which the light is utilised, by way of maximising the surface area of the photo catalyst, and the ability to tailor the volume and flow rate of water, such that the maximum efficiency of reaction is achieved. When each of these elements is optimised, the cost of removing the small organic molecules in the effluent is relatively reduced.

The basic components of the present invention include: An optical transporter comprising an optical fiber or an optical sheet. These can be made of any optically clear materials, most usefully comprising an optically clear path in the UV (where UV light is preferred). Typically, such optical transporters are made of inorganic glasses or polymeric materials. At the very least, the core of the optical transporter requires a higher refractive index material, optionally surrounded by a cladding of lower refractive index material. Such optical transporters are well known in the telecommunications, data-communications and aesthetic lighting industries. Potentially useful additional elements include light scattering functionality in the optical transporter in order to distribute the UV light substantially orthogonal to the incident light path. Such scattering ability may be achieved via the inclusion of small particles or physical defects, and will be elaborated upon, below. In a preferred embodiment, the optical transporter is a waveguide that propagates light from the light source to the photocatalytic sheet. The light source can be any light source capable of producing a beam of the desired wavelength, although preferred embodiments of the present invention may employ one or more light emitting diodes (LEDs). The waveguide advantageously uses common fibre optics techniques to ensure that essentially all the light is propagated to the sheet, (i.e. using a lower refractive index surface layer). The waveguide may allow the light source to be remote from the photocatalytic sheets that are in the reactor.

The present invention includes a photocatalytic material, most preferably placed upon the surface of the optical transporter. For example, TiO ₂ can be coated onto one or more exterior surfaces of a polymeric optical sheet. Such a coating may be imparted upon the optical transporter by a variety of means, including solvent-based coating techniques, similar to processes currently used to place protective coatings on optical fibers. Alternatively, such a coating can be achieved during production of the optical fibers by bringing a cooling optical fiber into contact with TiO ₂ powder. Many other means of achieving a functional coating of a photocatalytic material onto an optical transporter may be envisaged.

A further means by which the TiO ₂ coating may be imparted onto the optical transporter involves high-temperature annealing of the TiO ₂ so as to bind

the TiO ₂ particles to each other. For a glass coating, this process is generally carried out at around 400 ⁰ C, although in the case of a plastics-based optical transporter having a lower melting point, a relatively lower annealing temperature is required. The coating of the optical transporter may be further facilitated through use of a porous silica as a binding agent for coating the TiO ₂ Such a process may comprise mixing pre-formed TiO ₂ nanoparticles, said nanoparticles themselves comprising and approximate anatase-to-rutile ratio of 95:5, with a mix of siloxane molecules that when cured form a nanoporous silica. The resultant nanoporous silica is expectably an effective binder for the TiO ₂ and has sufficient porosity to expose much of the TiO ₂ to water.

Further applications of this technology could apply a variety of so-called "sol-gel" siloxane systems, such as those developed at the University of Queensland, Australia, by Paul Meredith. Further coating techniques may involve embedding agglomerates of TiO ₂ onto the surface of the plastic or glass optical transporter, and then grinding back the surface to expose the agglomerates.

In a preferred embodiment, photocatalytic sheets comprising a non- photo catalytic, optical substrate, and having a surface layer of photocatalytic material (e.g. TiO ₂ ), comes into contact with the aqueous gas or fluid that is to be remediated or processed. This surface layer is coated/immobilised on to one or more external surfaces of the substrate. The substrate is made of a material such as an inorganic glass, or plastic, that is substantially optically clear, thereby allowing light of a wavelength of about 200 nm to about 400 nm to pass through its entirety. Using fibre optics and/or commercial light propagation techniques (e.g. scattering, notching, particles, layers of different refractive indices, layers such as optical cladding, etc.) allows the light to reach substantially all the exterior photocatalytic surface material.

In another preferred embodiment, 'potting' of one or more of the optical transporters into a cartridge allows separation of the optical path from the water transport path. Typical examples include a fiber filter cartridge directly analogous to hollow fiber membrane cartridges, with the exception that such fibers are solid optical fibers. Yet another important example is a rolled-sheet filter cartridge,

which is akin to a Reverse Osmosis membrane cartridge, except that an optical sheet replaces the membrane. The potting is achieved as in most membrane and filter cartridges, by the use of a polymeric system to seal the ends of the cartridge around the fibers or sheets. The present invention further comprises a UV light source at one or more ends of the optical transport layer that allows the distribution of light from the light source lamp down the optical transporter, thereby to scatter substantially orthogonally from the TiO ₂ coating and produce the sought radicals in water.

In a preferred embodiment, the UV light source is in the form of UV light from a light-emitting device, such as a diode, UV lamp, or groups/banks thereof. The light energy source is able to produce light within the wavelength spectrum of around 200-400 ran, most preferably, a tight beam of 350 nm, thereby to utilise a relatively optimum amount of the light energy. The optimum wavelength is below 380 nm, which corresponds to the maximum effective wavelength for undoped TiO ₂ photocatalysis. The light source may be part of the photocatalytic sheet, or remote therefrom, in which case it is adjoined thereto by a waveguide.

The present invention may also comprise a reactor vessel preferably having an inlet and an outlet, to allow an aqueous gas or liquid feed to enter the vessel, and then once treated, exit the vessel. Alternatively, the inlet is integral with the outlet, thereby to facilitate a batch treatment process if desirous. The inside of the vessel allows for an advantageous configuration of photocatalytic sheets/fibres to be attached, allowing the raw feed optimum contact time with the photocatalytic surface of the sheets/fibres.

The vessel also has a port that allows the waveguide, or energy source for the light (e.g. UV lamp) to enter the vessel and affix to the sheets. This may be in a plate-and-frame arrangement shown in the accompanying drawings, a "Swiss roll" arrangement as used in the Reverse Osmosis module, or a plurality of vanes.

In a particularly preferred embodiment of the present invention, the solid plate optical transporter is replaced with a modified substrate, preferably comprising a substantially hollowed core portion. Such a modification is envisaged so as to potentially ameliorate the issue of light absorption in either the fused quartz, or acrylic plates disclosed above and described below. Light absorption in fused quartz or acrylic plates is demonstrable within the UV-C to

UV-A range, wherein there is a maximum of 90% transmission). Accordingly, one foreseeable solution is to use a gas or liquid as the medium for transmitting light to the TiO ₂ coating, thus creating a hollow substrate, or fluid substrate, rather than the current solid sheet. In one form of the present embodiment, the configuration consists in two optically-clear plates with a TiO ₂ coating on each plate, in accordance with the above disclosure. The space between the plates is filled with air, or an optically- clear material having around 100% transmission.

More preferably still, the end/s of the hollowed section would be fitted or equipped with a mirrored surface to reflect any incident light that had not been used on its first pass through the substrate.

The plates may be substantially parallel or non-parallel with respect to one another.

In this embodiment, the plates are separated by spacers, and sealed such that the air or fluid between the plates remains in the void. If the hollowed section were filled with a gas, or with a particular type of liquid, the resultant medium would have a relatively low Refractive Index compared with an optically clear sheet, and would thus cause insufficient reflection of the light along the hollow substrate, i. e. relatively more light may be absorbed into the sheets near the light source, as opposed to remote from it. To circumvent this potential problem, a reflective coating may be needed on the inside of the sheet to help create sufficient reflection and thus relatively uniform illumination along the length of the sheet; this can be modelled very accurately. This preferred configuration may apply to both "plate-and-frame" and "Swiss roll" configurations of the optical sheets.

In another preferred form of the present invention, there is no photo catalytic coating applied to the surface of the optical transporter. Accordingly, the inventive process is active to remediate at least a portion of the contaminant molecules via photolysis. Alternatively, the present invention provides for some coated surfaces, and some uncoated surfaces of the optical transporter. Accordingly, the present invention is operative via both photo catalysis and photolysis.

Brief Description of the Drawings

A preferred embodiment of the present invention will now be described by way of example and only with reference to the accompanying drawings and examples in which: Figure 1 is a side elevation of an optical fiber cartridge according to one embodiment of the present invention;

Figure 2 is a cross section taken on the line II -II of Figure 1, showing longitudinally-extending optical fibers potted within the cartridge;

Figure 3 is relatively magnified view of a single optical fiber as depicted in Figures 1 and 2, showing a preferred embodiment in which the three principal components of the fiber are a relatively high refractive index core, TiO ₂ surface coating, and a relatively low refractive index cladding;

Figure 4 is a side schematic view of a cartridge/module and filter housing adaptable to accommodate certain preferred embodiments of the present invention;

Figure 5 is an elevation of a single flat sheet, showing a relatively high refractive index optical core, optional relatively low refractive index cladding and surface coating of catalytic material;

Figure 6 is a side schematic representation of a "plate-and-frame" embodiment according to the present invention, employing a plurality of stacked optical sheets, and showing a tortuous or serpentine path along which the feed flows;

Figure 7 is a side view of a wound spiral Reverse Osmosis cartridge, again adaptable to certain preferred embodiments of the present invention; and Figure 8 is a side representation of a ""hollowed" waveguide according to a preferred embodiment of the present invention. In this instance, the waveguide comprises two spaced parallel plates defining a cavity therebetween. The cavity may be filled with an appropriate medium or media so as to facilitate propagation of the incident energy down the waveguide and into the reaction vessel.

Preferred Embodiment of the Invention

A preferred form of the apparatus according to one aspect of the present invention comprises a catalytic substrate, which is preferably a photocatalytic

substrate, most preferably being TiO ₂ , in the form of anatase, rutile, titania or a combination thereof.

The apparatus also includes means for providing a feed comprising one or more predetermined reactants. The feed is a fluid, most preferably being a liquid, gas, or a combination thereof. More preferably, the fluid is a fluid effluent, with the method thereby operative to remediate at least a portion of the fluid effluent. In a particularly preferred embodiment, said fluid effluent is a contaminated or polluted liquid, gas and/or steam. The liquid, gas and/or steam comprises one or more predetermined reactants in solution and/or undissolved state. Most preferably, the liquid is water.

The means for providing a feed includes provision of an outlet port remote from an inlet port, thereby to facilitate flow of said feed therebetween. Alternatively, the inventive apparatus includes provision of an outlet port integral with an inlet port, thereby to facilitate the method to operate on a batch basis. The apparatus also comprises an energy source spaced from the catalytic substrate, or the energy source may be proximal with the catalytic substrate. More preferably, the energy source is directly coupled with the catalytic substrate. The energy is light, most preferably comprising one or more wavelengths within the range of approximately 200-400 nm. The apparatus also comprises a transport medium through which energy derived from said energy source is contactable with said catalytic substrate, thereby to provide a species active against said one or more predetermined reactants. In a preferred embodiment, the transport medium is a waveguide. More preferably, the waveguide is a planar optical waveguide. The waveguide may act both as the transport medium and as a substrate for catalytic material applied to the surface thereof. Preferably, the waveguide comprises a single material. Alternatively, the waveguide comprises a plurality of materials. Preferably, the plurality of materials are of differing refractive indices, thereby to relatively enhance the waveguiding efficiency of the waveguide. The waveguide may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate incident light being shifted out of the plane of the waveguide and contacting with the photocatalyst. The active species is an excited species, most preferably, the

excited species are free radicals.

The apparatus also comprises means for contacting said active species with said feed, thereby to actively effect said predetermined chemical transformation. As such, the catalytic material is applied to one or more surfaces of the catalytic substrate. Preferably, the catalytic material is illuminated substantially perpendicular to the axis thereof. Alternatively, the catalytic material may be illuminated substantially parallel to the axis thereof.

The catalytic material is provided as a coating over one or more surfaces of the waveguide. Foreseeably, the coating is adhered to the waveguide via solid phase, gas phase and/or liquid phase deposition techniques. Such deposition techniques comprise annealing, adhesive, etching, extrusion, moulding, dip coating, sputter coating, slot coating, lamination, or a combination thereof .

The coating may be on a substantially smooth or complex surface. Most preferably, the waveguide has a complex surface. The complex surface is applied upon the waveguide by etching, extrusion moulding, stamping, or a combination thereof.

In one embodiment, the complex surface is formed in the same material and is integral with the waveguide. Alternatively, the complex surface is formed separately from the waveguide. Preferably, the complex surface is formed in a different material to the waveguide. The complex surface facilitates enhanced fluid dynamics, such as relatively enhanced flow rate and/or relatively enhanced mixing. The complex surface also increases the effective surface area of the catalytic substrate.

The solution comprises said one or more predetermined reactants in aqueous phase. The contaminated or polluted liquid comprises one or more organic contaminants. More preferably, the one or more organic contaminants comprise organic molecules and organisms. More preferably still, the organic molecules comprise 1,4-dioxane and/or iV-nitrosodimethylamine (NDMA).

Alternatively, the one or more organisms comprise bacteria, protozoa and/or viruses.

The waveguide ideally comprises one or more stacked sheets. The arrangement of one or more stacked sheets are spaced by one or more discrete spacer units and/or the complex surface. The one or more stacked sheets are

arranged to provide optimal contact time of the feed with the active species. Ideally, the one or more stacked sheets are arranged to provide a relatively increased surface area per unit volume. The arrangement of one or more stacked sheets are arranged to provide a serpentine flow of the feed between the sheets. In a preferred embodiment, the relatively increased surface area is enabled by way of a plate-and-frame type configuration. Preferably, the plate-and-frame type configuration comprises a plurality of sheets stacked substantially horizontally. In another preferred embodiment, the relatively increased surface area is enabled by way of a Swiss-roll type arrangement. In a further preferred embodiment, the relatively increased surface area is enabled by way of a vane type arrangement.

According to a preferred embodiment, the predetermined chemical transformation takes place within a modular apparatus, as exemplified in Figure 6. The present invention provides a chemical reactor (filter) vessel that enables dissolved small organic compounds, e.g. iV-nitrosodimethyleamine (NDMA) or 1,4-dioxane, in an aqueous gas or aqueous liquid feed to be destroyed or broken down by an advanced oxidation process (AOP), undertaken in a photocatalytic reaction. The reactor vessel enables UV light to be transmitted from a light source, to a configuration of sheets, each said sheet having a photocatalytic surface that enables the photocatalytic portion thereof to undergo photo catalysis, which in turn produces an AOP to destroy organics present in the gaseous or fluid feed, as it passes over the surface of the sheets.

In the following description, a preferred embodiment of a Hollow Fiber Optical Transporter according to the present invention is exemplified in Figures 1 to 3. In this example, the optical transport medium is a plurality of optical fibers 1, which are 'potted' into a cartridge 2, the cartridge being analogous to a kidney dialysis or microfiltration cartridge.

The optical fibers 1 extend longitudinally down the cartridge 2, and are affixed at the respective ends 3 and 4 by a potting compound 5. The potting compound 5 serves both to fix the optical fibers 1, and also to seal the ends of the cartridge 2 such that water cannot pass through the ends thereof. The cartridge 2 optionally includes a screen 6 to support the outermost optical fibers and maintain the mechanical rigidity of the cartridge 2 for transport and installation.

Referring specifically to Figure 2, in which an end-view of the cartridge 2 is depicted, in which the exposed ends of the optical fibers 1 can be seen. It is through these ends that the UV light is propagated down the fibers.

Referring specifically to Figure 3, in which a close-up of an optical fiber 1 in the cartridge 2 is shown, the optical fiber is typical inasmuch as that there is a core 7 of relatively high refractive index and an optical cladding 8 of relatively lower refractive index. Accordingly, the optical fiber will guide light. Optionally, the fiber 1 may have a protective coating. In this preferred embodiment, the optical fiber has a coating of TiO ₂ on its outermost surface 9, the TiO ₂ coating being in contact with the water or other fiowable material bearing the chemical reactant(s).

Optionally, the optical fiber 1 may be manufactured from polymeric materials such as polycarbonate or acrylics. Fluorinated polymers can be used if enhanced oxidation resistance of the polymer is required. Polymeric optical fibers have the advantage that they are readily available, relatively low cost, available in any specified diameter, and are insensitive to water exposure.

An enhancement in the optical fiber 1 according to the present invention is the use of scattering to ensure that relatively more of the light that enters the ends of the optical fibers is usefully, and evenly scattered into the cladding 8 of the fiber, and thus efficiently converted into radicals after interaction with TiO ₂ at the outer surface 9 of the optical fiber 1. The outer surface 9 of the optical fiber is, it should be remembered, in contact with the water, or effluent feed. Such scattering can be achieved by the addition of scattering particles into the core and/or cladding of the optical fiber, or by the inclusion of physical notches in the cladding of the optical fiber. Such techniques are well known- in the application of optical fibers for aesthetic "side-lighting" purposes, and can be tailored such that light is scattered relatively evenly along the length of the optical fiber, despite one end of the optical fiber being closer to the light source.

Referring now to Figure 4, in which a schematic of the filter cartridge 2 and housing 10 is provided, two UV lamps 11 and 12 illuminate the respective ends 3 and 4 of the optical fibers 1 at each end of the cartridge 2. The UV light passes along the optical fibers, and is scattered onto the surface of the optical fibers, where it reacts with the surface coating of TiO ₂ and the water to create

radicals. The water flows in to and out of the cartridge via the ports 13 and 14, as illustrated, and follows a tortuous path between these ports. Accordingly, there is a relatively increased contact of water with the surface of the optical fibers. Along this path, the organic molecules in the feed water react with radicals produced at the surface of the optical fibers to produce relatively harmless decomposition products. The optical fiber diameter and density, together with the water flow rate is optimised so as to relatively minimise the overall cost of treating the water. The end-pots, as shown, seal the water from the UV lamps. The housing and other engineering used for such a cartridge is advantageously adapted from microfiltration, ultrafiltration or Reverse Osmosis membrane cartridges.

Referring specifically to Figure 5, a preferred format for the optical transporter 1 is a Flat Sheet Optical Transporter 15, as shown. The optical transporter sheet may be comprised of plastic, inorganic glasses or other suitable materials. The optical transporter sheet can be constructed of one or more optical layers.

Optionally, the optical transporter sheet comprises a photocatalyst layer, e.g. TiO ₂ , upon its outer surface 16. The photocatalyst layer 17 is applied by any suitable means (e.g. liquid coating, powder coating, lamination, etc.). The essential theory behind the use of the flat sheet is that the incident UV light is sent through the ends 18 of the flat sheet 15, and emitted through the surface of the sheet, whereupon the UV light interacts with water and the photocatalyst to create the radicals by which the organics are decomposed.

A flat sheet optical transporter can be integrated within the inventive remediation system in many ways. Two prime examples are provided in Figures 6 and 7.

Specifically, the arrangement depicted in Figure 6 could be termed the "plate-and-frame" configuration. In this arrangement, successive flat sheets of optical transporter material 15 are layered on top of each other, spanned by supporting spacer material 19.

Between the sheets, spacers may be used to separate the sheets, allowing the fluid/gas feed to pass between, and to ensure that fluid/gas flow is evenly distributed across the surface, optimally crating a mixing action.

In a particularly preferred embodiment, the photocatalytic surface is formed by etching, extruding, moulding, or any other known or applicable means. The photocatalytic surface may comprise a complex surface to allow an increase in surface area, whilst at once helping the fluid dynamics (i.e. flow, mixing) of the system. The complex surface may even function as the spacer, in which case the photocatalytic sheets are self-stacking. In employing the method provided by the present invention, the photocatalytic surface is self-cleansing.

The entire stack is then edge-glued in such a fashion as to seal the edges, thereby to stop water from leaking out at the edges. However, this operation is performed in such a manner as to still allow UV light to be illuminated into the optical transporters. The perceived water flow is depicted in Figure 6, wherein it should be appreciated that the water flows right through the module 20 from inlet 21 to outlet 22 in a controllable fashion.

The second such example, as depicted in Figure 7, is the "spiral wound"- type configuration often used for Reverse Osmosis membranes. In a hollow pipe cartridge housing 23 is a flat sheet 24 (not shown) having a space both above and below it. Prior to placement in the cartridge 23, the stack is wound into a spiral, and the spiral is then edge-glued in such a fashion as to allow light to be illuminated into an optical transporter. This configuration is directly analogous to the "plate-and-frame"-type configuration disclosed above. However, it has been found that the spiral configuration is relatively cheaper to fabricate.

In terms of the comparative advantages of flat sheet and hollow fiber configurations, the most important consideration is cost per quantity of water treated. Overall cost comprises initial capital expenditure plus operating and maintenance costs. Also important is the time and expenditure required to develop new water treatment technologies, which directly takes account of the degree to which earlier non-patented engineering technologies may be incorporated, both from photonics and membrane water treatment processes.

Optical fibers are now readily available at relatively low cost, whereas a flexible flat optical sheet is a boutique specialty product used for aesthetic lighting. However, almost any optically clear extruded polymer sheet could be used. Since this application does not require high definition optics, a simple three-sheet polymer laminate could be used. One such example is that of

relatively low cost everyday plastic films, such as PET or acrylics, laminated together with heat, and with optional glues. In certain circumstances, the optics may be forgiving enough such that a single polymer film layer is sufficient.

Compared with the optical fibers, flat sheet technology is relatively easy to handle, easier to make into a module, and even relatively easy coat with TiO ₂ . Also, flat sheet offers the advantage of a defined liquid flow path, whereas in using fibers, the flow path is never optimal. Essentially, using fibers, a preferred path is created by the water flow pushing the fibers aside, and optimal contact time is seldom achievable. With flat sheet technologies, the development costs required in order to optimise the system can be met in a plate-and-frame laboratory experiment. Accordingly, one can use an inflexible sheet to prove the theory. Essentially, this embodies one or more sheets of Perspex coated with TiO ₂ in a plate-and-frame set-up, with UV lights shining at the edges. TMs leads to relatively low cost product development; the simple set-up described above gives rise to the optimal engineering parameters for the eventual product.

In water treatment using microfiltration, hollow fibers are generally preferred over a flat sheet. This is because the feed water is generally very dirty, thus leading to fouling, in addition to backwashing requirements. However, in the present invention the feed is envisaged to be relatively clean, and accordingly, fouling is much less of an issue.

Further, the present invention utilises cross-flow systems with no pressure across the 'filter'. In Reverse Osmosis membrane treatment, a flat sheet is preferred over hollow fiber systems. Those active in the relevant industry have in the past employed hollow fiber Reverse Osmosis. However, the overwhelming trend has been toward the flat sheet. This is because it is inherently cheaper, and there is no special requirement for a hollow fiber, namely solids-loaded feed water.

Accordingly, the most preferred embodiment .of the present invention is directed toward using a flat optical sheet. This could be in rolled-sheet format or plate-and-frame set-up. The principal advantages of such a system include optimising the energy efficiency in removing organic species by generating peroxide, in situ, ensuring relatively more of the light is converted to radicals, and

ensuring that the radicals are most efficiently used to react with the small organic molecules, as opposed to recombining with each other.

A further advantage resides in the use of existing filter and membrane cartridge technologies. This results in lower development and unit costs. It also allows a single or low count of UV lamp to illuminate an effectively large volume of water. Further, it allows the development of small area footprint treatment plant, which is a major factor in terms of cost and adoption of new treatment technologies.

Yet a further advantage of the present invention resides in it using existing cartridge designs, the ancillary engineering (pipes, pumps, valves, control systems, management software and hardware) will also be familiar and have relatively low cost. This engineering has a direct effect upon the volume-cost curve. Familiar engineering also lowers the barrier to adoption of this new technology within the marketplace. Referring now specifically to Figure 8, a preferred form of the present invention consists in an apparatus for delivering one or more active species 25 to a reaction vessel, thereby to effect a predetermined chemical transformation. The apparatus comprises means for providing a feed to said reaction vessel, the feed comprising one or more predetermined chemical reactants; an energy source 26, thereby to produce incident energy therefrom; a transport medium 27 communicable between the reaction vessel and the energy source, thereby to deliver the incident energy 25 proximal with the one or more predetermined chemical reactants; and means for contacting the active species with said one or more predetermined chemical reactants, thereby to actively effect said predetermined chemical transformation to give a remediated product.

It will be appreciated that the transport medium is a waveguide 27. The waveguide need not comprise a solid sheet as described in relation to Figures 1 to 7. Specifically, in this instance, the waveguide 27 comprises two spaced sheets denning a cavity 28 therebetween. The cavity is filled with any fluid medium 29, or mixture of fluid media that facilitate the propagation of the incident energy therethrough. As such, the fluid media 29 must have an appropriate refractive index, or other physical properties such that the incident energy 25 is not absorbed, deactivated or deflected elsewhere.

The channel 28 may comprise one or more gases, and/or one or more fluid materials. Foreseeable media 29 through which the incident energy can propagate include air, mineral oil/s, water or fluorinated siloxanes.

The incident energy 25 comprises the active species. Specifically, in this embodiment, the incident 25 energy is ultra violet light of between approximately 254 and 390 nm wavelength.

Optionally, the energy source 26 is associated with a catalytic substrate

30, thereby to actively convert the incident energy 25 to said one or more active species. In this case, the catalytic substrate 30 is again titanium dioxide. In an embodiment, the TiO ₂ is present as a secondary laminate coating at least part of one or more surfaces of the waveguide 27. Preferably, the titanium dioxide is of a uniform or non-uniform thickness of up to 20 microns; preferably, about 0.1 to 15 microns; most preferably, about 0.1 to 5 microns. Alternatively, if not comprising a catalytic substrate, the secondary laminate renders advantageous mechanical strength characteristics by way of reinforcing the rigidity of the waveguide 27.

The association of the catalytic substrate 30 with the waveguide 27 is alternatively such that the catalytic substrate 30 is suspended within the waveguide 27. Alternatively, the catalytic substrate 30 is dispersed within the feed of contaminated fluid undergoing remediation. However, in this latter case, any such method would necessarily comprise the further step of retrieving and/or recycling the catalytic substrate 30 from the remediated product.

In an embodiment, the waveguide 27 is constructed of a plurality of materials of different refractive indices, thereby to relatively optimise the waveguiding efficiency of the waveguide, relative to the predetermined chemical reaction being undertaken.

The waveguide 27 may comprise scattering centres, reflective elements, diffractive elements, or a combination thereof, thereby to facilitate the incident energy being shifted out of the plane of the waveguide, thereby to contact with the one or more predetermined chemical reactants.

The apparatus further includes provision of an outlet port remote 31 from an inlet port 32 providing the feed of contaminated material, thereby to facilitate flow of the feed therebetween. Alternatively, the apparatus comprises an

outlet port 31 integral with the inlet port 32, thereby to facilitate said method to operate on a batch basis.

The contaminated or polluted liquid foreseeably comprises one or more organic contaminants, such as organic molecules, pathogens bacteria, protozoa and/or viruses and/or other organisms. Of these, arguably the most significant organic contaminants are organic molecules comprise 1,4-dioxane and/or JV- nitrosodimethylamine (NDMA).

The waveguide may also comprise a mirrored or reflective surface 33 therewithin. This has the effect such that any incident energy 25 that is not deflected into the reaction vessel on a first pass is reflected back into the waveguide whereby it may be scattered on a subsequent pass. Accordingly, the present invention is relatively energy-efficient.

In summary, a system according to the present invention should have significant cost advantages. For a specific required removal rate of small organic molecules in Reverse Osmosis effluent, lower capex should be achieved, together with relatively reduced operating and maintenance costs.

In general terms, the present invention is advantageous in that it creates an efficient means to bring a reaction system together with activating light in a low cost cartridge, with the ability to adjust the relative surface areas and volumes with relative ease, in order to maximise the efficiency of the process.

One foreseeable application of the inventive system is for water treatment to remove dissolved organics. However, it would be readily apparent to one skilled in the relevant art that the system may have efficacy for any fluid reaction system where photocatalysis is required. Moreover, the means in which the photocatalyst is employed is optional; it can be placed on the surface of the optical transporter, as described, or even in suspension. The effluent phase can be a liquid or a gas. The light source can be any wavelength of light that is suitable to induce photocatalysis.

As used throughout the specification and claims, the term "waveguide" should be taken to mean a structure that is applied to transport incident energy from the energy source to the one or more predetermined chemical reactants.

Thusly, in the context of the present invention, the transport medium comprising, for example, one or more plastic sheets is taken to be the waveguide. In other

preferred embodiments of the invention, the waveguide is defined by the channel between two or more stacked plates (including he plates themselves). It will be appreciated that other interchangeable terms of the art may include "light box", "optical transporter", or "transport medium". Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

Similarly it should be appreciated that in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, FIG., or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this invention. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

Furthermore, some of the embodiments are described herein as a method or combination of elements of a method that can be implemented by a processor of a computer system or by other means of carrying out the function. Thus, a

processor with the necessary instructions for carrying out such a method or element of a method forms a means for carrying out the method or element of a method. Furthermore, an element described herein of an apparatus embodiment is an example of a means for carrying out the function performed by the element for the purpose of carrying out the invention.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

As used herein, unless otherwise specified the use of the ordinal adjectives "first", "second", "third", etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

In the claims below and the description herein, any one of the terms comprising, comprised of or which comprises is an open term that means including at least the elements/features that follow, but not excluding others. Thus, the term comprising, when used in the claims, should not be interpreted as being limitative to the means or elements or steps listed thereafter. For example, the scope of the expression a device comprising A and B should not be limited to devices consisting only of elements A and B. Any one of the terms including or which includes or that includes as used herein is also an open term that also means including at least the elements/features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising.

Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognise that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. For example, any formulas given above are merely representative of procedures that may be used. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks. Steps may be added or deleted to methods described

within the scope of the present invention.

Unless the context clearly requires otherwise, throughout the description and the claims, the words 'comprise', 'comprising', and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

Although the invention has been described with reference to specific examples it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.