Technical Field [0001] This disclosure relates generally to a process and system for plant essence extraction from a source of plant material. In particular, the disclosure relates to a process and system for producing plant essence that are energy efficient and provide a significantly reduced carbon foot print. [0002] In the last 15 years there has been a major consumer shift away from synthetically (chemically) derived ingredients for food, personal care, and home care products to "natural" and healthier product choices that are based on plant essences. This mentality is centred on a belief that these products are healthier, more environmentally friendly, and more socially responsible than the synthetic alternatives.

[0003] A plant essence is a concentrated hydrophobic liquid containing volatile aromatic and other compounds from a plant. Plant essences are also known as volatile oils, ethereal oils, aetherolea, or the oil of the plant from which they were extracted, such as for example lavender oil, eucalyptus oil or tea tree oil. A plant essence typically contains the characteristic fragrance of the plant from which it is derived.

[0004] Few consumers realise that the extraction of plant essences can be extremely energy intensive. In fact, over 50% of the energy requirement for the propagation, harvesting, and processing of these ingredients is in the actual processing of the harvested plant to yield the plant essence. The energy required to achieve this processing is often derived from the burning of fossil fuels and other carbon-rich sources, often with little control of the exhaust gases. Furthermore, as these processes occur according to a growing and harvesting seasonality, the processing stage requires intense energy consumption over a contracted time interval resulting in the under-utilisation of infrastructure and resources across the remainder of the calendar year. [0005] Various plant essences are used in perfumes, cosmetics, soaps, personal care, home care and other products, including medicinal/therapeutic, for their functional characteristics (e.g. antibacterial, antifungal, antiviral, and/or anti-inflammatory), for flavouring food and drink, and for adding scents to incense and other products. Currently there are four primary types of plant essence extraction processes.

[0006] Hydrodistillation is a technique for extraction of essential oils. It is used for its simplicity but requires high energy consumption for heating and cooling. Many organic compounds present in plant essences tend to decompose at high sustained temperatures. Separation by hydrodistillation is where water or steam is introduced into the distillation apparatus. The water vapour carries small amounts of the vaporized compounds to a condenser, where the condensed liquid phase separates, allowing for easy collection. Usually the immediate product is a two-phase system of aqueous and organic distillates, allowing for separation of the components by decantation, partitioning or other suitable methods.

[0007] Mechanical Pressure Expression is a technique whereby physical force is exerted by mechanical presses to express a liquid component from plant biomass. An example of this is the pressing of olives to derive olive oil. This system can be batch specific or an in-line continuous pressing system.

[0008] Gas Pressure Expression is a relatively new process, primarily using carbon dioxide (C0 ₂ ) in an enclosed vessel to generate high physical pressure to push the essence from the biomass. This technique has the advantage of achieving extraction under any temperature condition, preserving any volatile elements which can be lost in a heat -based hydrodistillation process.

[0009] Steeping Extraction is a process of extracting plant biomass elements using water in its liquid phase as a solvent. This may be done at various temperatures.

[0010] This present disclosure seeks to a process and/or a system that utilises a combination of renewable energy sources, the storage of this energy, and optionally an integrated re-cycling of thermal energy, to achieve a reduced carbon footprint across the production process of extracting plant essences. Summary

[0011] In a first aspect, embodiments are disclosed of a process for the extraction of plant essence from a source of plant matter, the process including the following steps: a) harvesting a crop of a plant to provide a source of plant matter, and,

b) processing the source of plant matter to produce the plant essence and biomass, wherein at least part of the energy used in processing step b) is derived from hydrogen gas.

[0012] In one form the hydrogen gas is generated from the electrolysis of water. In one form the electricity used in the electrolysis of water is derived from renewable energy.

[0013] In one form at least part of the hydrogen gas is derived from a hydrogen gas storage apparatus. In another form the hydrogen gas storage apparatus is selected from a hydrogen compression storage and dispensing (CSD) apparatus.

[0014] In one form the renewable energy is selected from one or more of the following: wind energy, solar energy, hydro energy, tidal energy and/or geothermal energy. In one form the renewable energy is solar energy. [0015] In one form step b) includes one or more of the following processes to process the source of plant matter to provide the plant essence and the biomass: hydrodistiUation, mechanical pressure expression, gas pressure expression and/or steeping extraction. In one form step b) includes a hydrodistiUation process to process the source of plant matter to provide the plant essence and the biomass and a distillate.

[0016] In one form at least part of the heat used by a boiler for generating steam used in the hydrodistillation process is provided by the combustion of hydrogen gas.

[0017] In one form the heat used by the boiler for generating steam may also be provided by one or more of the following sources: solar hot water, geothermal energy, waste heat and/or solar hot water storage.

[0018] In one form the aqueous distillate produced by the hydrodistillation process is treated to provide water and a concentrated hydrosol. In one form the water is used in the electrolysis of water as herein described.

[0019] In one form the hydrogen gas is introduced to a hydrogen fuel cell to produce electricity which is used to power machinery and/or vehicles to facilitate processing step a) and/or processing step b). [0020] In one form the hydrogen gas is used to power machinery and/or vehicles to facilitate processing step a) and/or processing step b).

[0021] In one form the renewable energy provides a source of electricity that is used to power machinery and/or vehicles to facilitate processing step a) and/or processing step b).

[0022] In one form processing steps a) and b) are undertaken proximate to where the crop of the plant is grown and harvested. In one form processing steps a) and b) are undertaken within 30 km to where the crop of the plant is grown and harvested. In a further form, step b) is undertaken within 48 hours, and preferably within 24 hours after step a). In a further form the hydrogen storage apparatus is proximate to where processing steps a) and b) are undertaken.

[0023] In one form the plant is tea tree and the plant essence is tea tree oil.

[0024] In another aspect, embodiments are disclosed of the use of hydrogen gas in the processing of a source of plant matter to produce plant essence and biomass wherein the hydrogen gas is produced from a source of renewable energy. In one form the hydrogen gas is produced from the electrolysis of water wherein the energy used in the electrolysis of water is derived from the source of renewable energy.

[0025] In one form the electricity used in the electrolysis of water is derived from renewable energy. In one form the renewable energy is selected from one or more of the following: wind energy, solar energy, hydro energy, tidal energy and/or geothermal energy. In one form the renewable energy is solar energy.

[0026] System for the extraction of plant essence from a source of plant matter, the system including:

• processing plant for processing the source of plant matter to produce the plant essence and biomass,

• hydrogen gas storage apparatus for storing a supply of hydrogen gas, wherein at least part of the energy used by the processing plant is derived from the hydrogen gas provided by the hydrogen gas storage apparatus,

• an electrolyser for producing hydrogen gas from a supply of water, the electrolyser configured to deliver hydrogen gas to the hydrogen gas storage apparatus, and,

• a source of electricity to operate the electrolyser, the source of electricity being derived from a renewable energy source.

[0027] In one form the processing plant is a hydrodistillation plant.

[0028] In one form at least part of the heat used by a boiler for generating steam used in the hydrodistillation plant is provided by the combustion of hydrogen gas provided by the hydrogen gas storage apparatus. [0029] In one form the renewable energy source is selected from one or more of the following: wind energy, solar energy, hydro energy, tidal energy and/or geothermal energy.

[0030] In one form the renewable energy source is solar energy that is then converted to electricity using photovoltaic solar cells for use by the electrolyser.

[0031] Other aspects, features, and advantages will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which are a part of this disclosure and which illustrate, by way of example, principles of inventions disclosed.

Description of the Figures

[0032] The accompanying drawings facilitate an understanding of the various embodiments.

[0033] Figure 1 is a schematic diagram illustrating an embodiment of the process and/or system disclosed herein; and,

[0034] Figure 2 is a schematic diagram illustrating a further embodiment of the process and/or system disclosed herein.

Detailed Description

[0035] What has been identified with the development of the process and/or system described herein is that a single source of renewable energy is not sufficient to satisfy the concentrated energy demand of a plant essence extraction process during the processing time periods each year in a manner that is able to sufficiently replace the use of energy derived from fossil fuels. [0036] The plants used as the primary source for a plant essence are typically grown on a farm requiring little energy input during the planting, growth and even harvesting phase of their crop life cycle. The energy required to drive the machinery and farm utilities often utilised during these phases, may be supplied by a renewable energy resource with little supplement from other energy sources such as those derived from fossil fuels. However, the process of extracting the plant essence from the harvested plant material is very energy intensive. As a result, if a source of renewable energy such as solar or wind energy is desired to provide the energy demands of the extraction process, a large capital outlay would be required to provide sufficient renewable energy required during this peak period. Furthermore, solar and wind energy also have the disadvantage that they do not produce significant energy when the sun is not shining or the wind conditions are not ideal.

[0037] According to certain embodiments, solar energy including both thermal and photovoltaic may be utilised to create potential energy reserves which may be employed during the seasonal energy intensive plant essence extraction process.

[0038] In certain embodiments, the thermal energy may be stored in insulated water tanks whereas the electricity produced from solar photovoltaic sources may be used to drive an electrolyser to produce hydrogen gas and oxygen. Once produced, the hydrogen gas may be safely stored under (relatively) low pressure conditions for subsequent use in the seasonal energy intensive plant essence extraction process.

[0039] In certain embodiments latent and waste heat may also be captured, or extracted from the system at one point and applied elsewhere in the system to optimise energy consumption.

[0040] Referring to Figure 1 there is shown a schematic representation of an embodiment of the present disclosure in the form of an Energy Management Schematic. The figure outlines the systemic nature of this system, whereby elements of the system may be used to generate and consume thermal and electrical energy. There are three energy systems which are illustrated, a thermal heat system (1), a hydrogen system (2) and an electrical power system (3). Each of these energy systems contributes to energy production which is utilised throughout the various phases of the plant essence production including the planting, growth and harvesting phase as well as the energy intensive plant essence extraction phase. [0041] To provide sufficient energy to cope with the demand of the energy intensive plant essence extraction process, it is proposed to supplement otherwise sourced renewable energy with a hydrogen production and storage system that itself may be driven using renewable energy. For example and in reference to Figure 1, solar energy (4) may be used to generate electricity using solar photovoltaic cells (5), and this electricity (6) may be used to produce hydrogen resulting from the electrolysis of water in an electrolyser (7). The electrolyser (7) may be operated at anytime throughout the year when solar energy (4) provides sufficient electricity (6) via the photovoltaic cells (5) and the hydrogen gas produced by the electrolyser (7) may be stored in a hydrogen storage and dispensing apparatus (8) (such as for example a hydrogen compression, storage and dispensing unit, or CSD) until such time that the hydrogen gas is needed for the energy intensive plant essence extraction process (9), (13).

[0042] In certain embodiments the renewable energy used to produce the electricity to drive the electrolysis reaction to produce hydrogen may be derived from any suitable renewable energy resource including wind energy, solar energy, hydro energy, tidal energy and/or geothermal energy. In typical locations where plants are farmed and harvested for the production of plant essence, it would be likely that solar or wind energy would be the most suitable and available forms of renewable energy for driving the electrolysis of water. [0043] In certain embodiments, the hydrogen that is produced from the electrolysis of water (7) may be stored in the hydrogen storage and dispensing unit (8) and then subsequently used to assist in the extraction of the plant essence (9) (13). The process of extraction may include one of the following processes: hydrodistillation, mechanical pressure expression, gas pressure expression and/or steeping extraction. The hydrogen gas may be used to provide a source of heat if applicable to selected process of extraction, or alternatively it may be used by a hydrogen fuel cell (10) to produce electricity (11) which may then be utilised in the distillation process (9). For example and as shown in Figure 1, when hydrodistiUation (13) is used to extract the plant essence, the hydrogen gas (12) may alternatively be used as the fuel and combusted to heat a boiler to produce hot water and/or steam for use in the hydrodistiUation process (13).

[0044] In addition to assisting with the energy intensive demands of the extraction process, the hydrogen gas produced and stored as part of the hydrogen storage and dispensing apparatus may be used to directly drive farming equipment (14) used in the planting, growth and harvesting phases of the plant production used in the plant essence extraction process (9) (13). Furthermore, the hydrogen may be used as the input to a hydrogen fuel cell (10) that may generate electricity (11) to supplement the electric power system (3) as shown in Figure 1.

[0045] In certain embodiments, solar power (4) may also be used by the thermal heat system (1) identified in Figure 1 where solar energy (4) from the sun may be used to heat water 21) which may then be stored (16) and used in the plant essence extraction process (13). For example, the heated water (15) using solar energy (4) may be stored (16) and then subsequently used to supplement the heating required to produce hot water or steam (17) as part of a hydrodistiUation process (13).

[0046] In certain embodiments, an aqueous distillate (18) is produced when processing plants to produce a plant essence using a hydrodistiUation process (13) which may be treated (22) to provide water for use in an electrolysis reaction in the electrolyser (7) to produce hydrogen gas and a concentrated distillate (or hydrosol) (19). In addition to the by-product hydrosol, plant biomass (20) is another by-product which is derived from the plant essence extraction process.

[0047] The process and system herein described are essentially non-mechanical, which may yield an extended usable lifespan without significant ongoing maintenance costs. [0048] In certain embodiments a system is disclosed for use on farming installations with in-situ plant essence extraction processes which may utilise thermal energy sources (e.g. solar thermal, thermal release, hydrogen burn) to generate/remove heat with the highest thermal efficiencies, while electrical energy (e.g. solar PV) is used for electrical system requirements.

[0049] Referring to Figure 2, there is shown a total farming process chart for use with a farming installation for the production of a plant that is subsequently the feed stock for an in-situ plant essence extraction process. As is demonstrated in the Figure, excess energy generated from the renewable energy sources (40) is converted into hydrogen gas and stored (41) for use in the energy intensive plant essence extraction process (42). Excess energy that is not taken up in the plant essence extraction process 42) may be employed for electrical energy to process waste by-products (43) (e.g. biomass fermentation processes yielding bioethanol, hydrosol concentration, etc.) and loading of hydrogen fuel cells to run tractors, forklifts, and other equipment on the property (44).

[0050] There are several advantages that are provided by various embodiments of the process and system described herein including: that the process and system are able to achieve a 'true' zero carbon capability as opposed to "Carbon Neutral" position. This is because the proposed system and apparatus provide the ability to store excess energy throughout the year in the form of stored hydrogen gas which may be used during the energy intensive plant extraction processes. Another advantage is that thermally efficient use of waste heat recovery and dissipation to feed the plant essence extraction process which also assists in reducing the entire energy demand of the process and system.

[0051] The process and system as herein described when applied to the extraction of plant essences for use in consumer products, yields a true "environmentally friendly" energy supply system to be used by manufacturers across the globe wanting to reduce their carbon footprint. In addition, the process and system enables intensive short-term, high- energy consuming production facilities to go "off the grid" with an environmentally sustainable solution, eliminating the need for fossil fuel or carbon burning of any fashion. [0052] In the foregoing description of preferred embodiments, specific terminology has been resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar technical purpose.

[0053] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as, an acknowledgement or admission or any form of suggestion that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

[0054] In this specification, the word "comprising" is to be understood in its "open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is the sense of "consisting only of. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear.

[0055] In addition, the foregoing describes only some embodiments of the invention(s), and alterations, modifications, additions and/or changes can be made thereto without departing from the scope and spirit of the disclosed embodiments, the embodiments being illustrative and not restrictive.

[0056] Furthermore, invention(s) have been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention(s). Also, the various embodiments described above may be implemented in conjunction with other embodiments, e.g., aspects of one embodiment may be combined with aspects of another embodiment to realize yet other embodiments. Further, each independent feature or component of any given assembly may constitute an additional embodiment.