Field of invention

The present invention relates to a solid-liquid waste treatment system and in particular, although not exclusively, to a waste treatment apparatus and method configured to separate and/or process human mixed solid-liquid waste from a toilet and optionally liquid wastewater from a sink.

Background

The commercial transportation industry including aircrafts, marine vessels, trains and road vehicles is generally required to have public conveniences/ washroom facilities for passengers. With regard to railway transport, historically waste from trains has been simply deposited on the tracks preferably as the train is in motion. Similarly, marine vessels typically dumped waste overboard directly into the sea or waterways. Due to increasing environmental awareness, the practice of depositing untreated human waste directly on land or in the sea has become undesirable and, in some instances, prohibited. Accordingly, solutions for managing on-board waste have been required. This has led to on-board storage facilities including in particular large liquid-solid waste storage tanks. Typically for trains, these tanks require regular emptying and this is typically undertaken using pumping systems that may be connected to the trains when stationary. However, such storage and pumping extraction processes are disadvantageous for several reasons. Firstly, an appreciable on-board volume is required to accommodate the storage of tanks. These tanks add additional weight which in turn, increases the fuel or energy demands of the train engine/motors. Additionally, particularly for long distance transport, it is common for waste storage tanks to be filled to capacity before the journey end, rendering the public convenience unusable. The infrastructure to support waste tank emptying and processing increases the train servicing time between journeys. Finally, the untreated waste extracted from the train still requires transportation through interconnected sewage pipe work networks, to a designated waste processing facility. This extraction process presents hygiene and personnel safety issues and the further transportation of the large volumes of untreated waste increasing the inefficiency of the overall waste treatment process.

As railways continue to expand and journeys extended to cross international borders, journey times are becoming longer. To attract more passengers to the railways, improved convenience and comfort are required. In particular, there is a requirement for modern rolling stock to make available to passengers, modern and reliable public conveniences including specifically toilet and washroom facilities continuously throughout the journey duration. This can prove challenging for railway transportation operators as on-board water supplies and waste storage tanks become exhausted.

US 6,585,899 describes waste processing systems for use on-board vehicles including trains, buses, aeroplanes and boats. Liquid waste is evaporated and solid waste is converted to ash and either stored in a filter or discharged as carbon into water, air or onto the railway tracks. WO 2010/050792 describes a waste processing system adapted for the incineration of human waste. The heat source for incineration may include gas, microwaves, resistance heating elements, electrical or laser energy. A heat exchanger system is utilised to recover heat from hot air generated as part of the incineration process.

However, there is a need for improved waste processing systems particularly suitable for public transportation vehicles and in particular those operating for use with extended or long journey times.

Summary of the Invention

A faeces processing system is provided adapted to process mixed liquid-solid and both liquid and solid waste from toilets/washrooms and/or sinks that is effective to both minimise the volume of solid waste and to filter and purify waste liquid suitable for recycling and/or further use. The present system is advantageous over existing systems in a variety of respects. In particular, the present system and apparatus may be integrated conveniently into existing transportation vehicles including aircrafts, marine vessels, trains, coaches and other road and haulage vehicles. The present system is also suitable and compatible for static installation, implementation and operation for example at construction sites and all manner of both public and private venues and locations that may have limited or no access to a water-based sewage network.

With regard to transportation vehicles and in particular trains, by way of example, the present system, by reducing the volume of solid waste and filtering and processing waste liquid, significantly reduces the need for freshwater replenishment and eliminates the requirement for any frequent processing and emptying of on-board waste storage tanks. Additionally, the present system significantly improves hygiene standards as ‘raw’ untreated human waste is processed immediately on-board. Vehicles fitted with the present system and/or apparatus will be lighter and adapted for carrying less tanking water and solid waste. This will, in turn, improve fuel and/or energy consumption efficiency as well as providing a more sustainable waste management system that avoids discharging solid and liquid waste directly into the environment. The present system also avoids a requirement for the hazardous and unpleasant task of emptying large storage tanks of untreated human waste for subsequent transport and site-based waste processing.

Fitted with the present system, it is anticipated that a typical train in normal operation would require significantly less waste servicing than trains with existing systems. Moreover, the toilet servicing time will be reduced accordingly as the solid waste is already processed and in a powdered char or ash form. Liquid waste having been filtered and cleansed on-board may be continually recycled and used on-board or deposited from the train safely and optionally for further use as desired. The present waste processing system reduces the requirement for toilet/restroom processing infrastructures at transportation hubs including for example railway stations, depots, airports, ports etc. The scheduling and transport logistics associated with conventional untreated waste processing is reduced significantly to further enhance the overall efficiency of human waste processing.

Importantly, the present system delivers wider socio-economic benefits including a reduction in the use of land-based sewage and water treatment infrastructure systems so as to provide a more sustainable waste management solution. In particular, the present system provides solid waste treatment to create a dry powdered solid that may be safely deposited and treated as "household’ waste. Recycled liquid generated from liquid waste from a toilet and/or a sink may be recycled for toilet flush and/or hand washing. Excess cleaned liquid may be discharged without environmental impact. The present system is also advantageous to recover energy during the processing steps to reduce the energy load and further enhance the environmental benefits.

Within this specification, reference to ‘human waste’ encompasses similar and equivalent terms including faeces, excrement, bodily waste, and solid waste passed from the body of a human.

Within this specification, reference to ‘predominantly solid human matter or waste’ encompasses faeces, excrement, bodily waste and equivalent terms being mainly solid and that may be mixed with a liquid urine as a minor phase. This term encompasses substantially solid, mainly solid and waste that comprises a majority solid phase with a monitory liquid phase by wt%.

Within this specification, reference to ‘predominantly liquid matter or waste’ encompasses liquid urine and equivalent terms being mainly a liquid phase that may include a minor solid phase comprising faeces, excrement. This term encompasses substantially liquid, mainly liquid and waste that comprises a majority liquid phase with a monitory solid phase by wt%, with such waste being from a toilet and/or a sink.

Within this specification, reference to ‘purification’ encompasses the process of sterilising and/or pasturing a liquid to terminate/kill bacteria and pathogens in a liquid. The term encompasses vapourisation and condensation processes and apparatus in which a distillate is collected as purified liquid and separated from a remaining slurry/solid-liquid mix. The term also encompasses other forms of sterilising and/or pasturing a liquid such as chemical treatment, biological treatment and/or irradiating with electromagnetic radiation. Combinations of these methods as described may be used.

According to a first aspect of the present invention there is provided human waste processing apparatus comprising: a solid-liquid separator connectable in fluid communication to a toilet, a predominantly solid matter outlet and a predominantly liquid matter outlet; a solid waste processing arrangement coupled to the solid matter outlet and having a heating unit with a heating chamber to heat and/or thermally decompose solid waste received from the separator and an evacuation unit to create at least a partial vacuum within the heating chamber; a liquid waste processing arrangement coupled to liquid matter outlet and having at least one particulate separation unit to separate solid particulate from the liquid received from the solid-liquid separator; a purification assembly coupled to the liquid waste processing arrangement to sterilise the liquid waste received from the liquid waste processing arrangement; and a syngas processing unit coupled to the heating unit to process syngas generated from solid waste processed by the heating unit.

Optionally, the heating unit comprises a dryer to dry solid waste received from the separator and a pyrolizer to thermally decomposed at least partially dried solid waste. Preferably, wherein the dryer comprises a dryer inlet connectable to the solid matter outlet of the separator to dry wet solid matter received from the solid matter outlet. Preferably, the dryer comprises a dryer outlet connectable to a heating unit inlet, the dryer configured to supply dried solid matter to the heating unit. Optionally, the heating chamber comprises solid matter outlet and a syngas outlet, the syngas processing unit coupled to the syngas outlet.

Optionally, the purification assembly comprises at least one output connectable to a processed liquid conduit network to provide a supply of liquid processed by the purification assembly.

Optionally, the at least one particulate separation unit comprises at least one filter to filter liquid received from the separator.

Preferably, the apparatus comprises a syngas processing unit to process syngas generated from solid matter processed by the heating unit, the syngas processing unit comprises a syngas combustion unit to combust syngas generated by the heating unit. Preferably, the combustion unit is located proximate to the heating unit to be capable of supplying heat energy generated from the combustion unit to the heating unit.

Preferably, the heating unit comprises at least one rotatable screw conveyor extending between a heating unit inlet and the solid matter outlet. Optionally, the screw conveyor comprises a twin-counter rotating screw conveyor. Preferably, the heating unit comprises an external heating element, wherein the heating chamber is an elongate tube and the external heating element is heating tape applied externally around the tube.

Preferably, the apparatus comprises a first toilet waste filter having a microscale filtration membrane. Preferably, the apparatus comprises a second toilet waste filter having a nanoscale filtration membrane. Optionally, the apparatus comprises a plurality of filters, to filter liquid win the system at various stages of processing. The filters may be the same type/ construed on or may differ in type and construction. Optionally, the filters are different based on a membrane size to provide a graduated/ staged filtration function. Preferably, the liquid waste processing assembly further comprises a solids settlement tank connected in fluid communication to the predominantly liquid matter outlet of the separator. Optionally, the liquid waste processing assembly further comprises a sludge tank connected in fluid flow with the solids settlement tank. Preferably, the liquid waste processing assembly further comprises a liquid treatment control tank connected in fluid communication to an outlet of the solids settlement tank. Preferably, the liquid waste processing assembly further comprising a liquid collection buffer tank connected in fluid communication to an outlet of the liquid treatment control tank.

Preferably, the first toilet waste filter and optionally the second toilet waste filter are positioned in fluid communication between the liquid treatment control tank and the liquid collection buffer tank; and/or optionally the second toilet waste filter is positioned in fluid communication between the liquid collection buffer tank and a toilet waste vapourisation tank.

Preferably, the apparatus comprises a sink waste processing unit to process sink liquid waste, the sink waste processing unit comprising any one or a combination of: a sink liquid waste tank; a sink liquid waste filter. Preferably, the toilet waste liquid filter is connected in fluid flow communication with the purification assembly. Preferably, the sink liquid waste filter is connected in fluid flow communication to the purification assembly. Optionally, the purification assembly comprises any one or a combination of at least one liquid distillation unit to at least partially vapourise and condense the liquid waste; a chemical treatment unit to chemically treat and pasteurise the liquid waste; an electromagnetic radiation unit to irradiate and pasteurise the liquid waste; a heating unit to heat the liquid waste at and/or above a pasteurisation temperature to pasteurise the liquid waste; a bio-treatment unit to biologically treat and pasteurise the liquid waste.

Optionally, the liquid distillation unit comprises a toilet waste vapourisation tank connectable in fluid communication to a toilet waste liquid filter and a sink waste vapourisation tank connectable to a sink liquid waste filter. Preferably, the purification assembly comprises a vapourisation unit having a heating unit provided at each of the toilet and sink vapourisation tanks to vaporise liquid within said tanks. Preferably, the purification assembly further comprises a heat exchanger unit having: a heating coil; a liquid circulation tank provided in fluid communication via a conduit manifold to the coil; a circulation pump to drive a fluid circulation through the heating coil and the liquid circulation tank.

Preferably, the purification assembly further comprises a toilet waste reservoir tank coupled in fluid communication to the toilet waste vapourisation tank via the heat exchanger unit to receive and store condensate generated from vapourisation of liquid within the toilet waste vapourisation tank; and the purification assembly further comprises a sink waste reservoir tank coupled in fluid communication to the sink waste vapourisation tank via the heat exchanger unit to receive and store condensate generated from vapourisation of liquid within the sink waste vapourisation tank.

Preferably, an outlet of the toilet waste reservoir tank is coupled in fluid communication to a toilet and/or a sink to provide a return of purified liquid to the toilet and/or the sink; and/or an outlet of the sink waste reservoir tank is coupled in fluid communication to a toilet and/or a sink to provide a return of purified liquid to the toilet and/or the sink.

Optionally, the apparatus comprises an untreated waste storage tank connectable in fluid communication to the separator inlet.

Optionally, the syngas processing unit comprises a syngas combustion unit to combust syngas generated by the heating unit.

Optionally, the combustion unit is located proximate to the heating unit to be capable of supplying heat energy generated from the combustion unit to the heating unit.

Optionally, the syngas processing unit is connectable in fluid communication with the heating unit, the syngas processing unit having: an air-syngas mixer to receive a flow of syngas from the heating unit and having an air intake to produce a syngas-air mixture; optionally a combustion control system to control a flow of the syngas-air mixture; a syngas combustion chamber to combust the syngas-air mixture; a biochar collection tank coupled to a gas outlet of the syngas combustion chamber, the biochar collection tank having an internal biochar collection chamber.

Optionally, the syngas processing unit further comprises: a biochar conduit connecting the biochar collection tank to the heating unit to receive biochar from the heating unit; and an exhaust gas valve connected to the biochar collection tank; wherein the biochar collection tank is configured to filter gas received from the gas outlet of the syngas combustion chamber via the biochar deposited in the biochar collection tank) from the heating unit.

Optionally, the syngas combustion chamber is located proximate to the heating unit and/or the apparatus further comprises a heat recovery and transfer arrangement to transfer heat energy from the syngas combustion chamber to the heating unit and/or the dryer.

Preferably, the apparatus comprises an untreated waste storage tank connectable in fluid communication to the separator inlet.

Optionally, the syngas processing unit comprises: a syngas chamber to receive the syngas; an air inlet port to allow a supply of air into the syngas chamber to mix with syngas; a heat transfer unit to cool and at least partially condense the syngas and/or a mixture of air and the syngas; and optionally a filter to filter the condensate generated by the heat transfer unit and to at least partially remove oil from the condensate. Optionally, the syngas processing unit comprises a liquid chamber to receive a liquid and a syngas chamber to receive syngas generated from the solid matter processed by the heating unit. Optionally, the syngas chamber is positioned at least partially within the liquid chamber. Optionally, the liquid chamber is connected in fluid communication to the purification assembly to receive liquid output from the purification assembly and/or a toilet waste reservoir tank.

Optionally, the syngas processing unit further comprises a filter to filter and at least partially remove oil from the syngas within and/or output at the syngas cooling chamber. Optionally, the apparatus comprises an air source connected in fluid communication to the syngas chamber to input air into the syngas chamber to be mixed with the syngas within the syngas chamber. Preferably, the apparatus comprises an air evacuation unit connectable in fluid communication with the untreated waste storage tank to partially evacuate an internal chamber of the waste storage tank.

Preferably, the solid-liquid separator comprises a rotatable drum having a drum inlet to receive untreated waste, an internal chamber accommodating a mesh screen, the drum also comprising the predominantly solid matter outlet and the predominantly liquid matter outlet. Preferably, the internal chamber of the rotatable drum is provided in fluid communication with the air pump unit suitable to create a partial vacuum within the internal chamber. Preferably, the solid-liquid separator comprises a mechanical actuator to rotate the drum between a first position to open the drum inlet to receive the untreated waste and a second position to close the drum inlet and open the predominantly solid matter outlet.

Preferably, the purification assembly further comprises a flush liquid waste pressure accumulator coupled to the toilet liquid waste vapourisation tank and a sink liquid pressure accumulator coupled to the sink liquid waste vapourisation tank.

Preferably, the apparatus comprises a sink liquid fresh liquid top up tank coupled to the sink liquid waste vapourisation tank to provide a supply of fresh liquid to the sink liquid waste vapourisation tank.

Preferably, the apparatus comprises a vapour deodorising filter coupled in fluid flow communication between the heating unit and a sink liquid waste vapourisation tank to deodorise vapour output from the heating unit prior to transfer to the sink liquid waste vapourisation tank.

According to one aspect of the present invention there is provided a method of processing human waste comprising: separating solid and liquid waste using a solid-liquid separator connectable in fluid communication to a toilet; heating and/or thermally decomposing solid waste received from the separator under at least a partial vacuum within a heating chamber of a heating unit; separating solid particulates from a liquid waste received from the solidliquid separator using at least one particulate separation unit; purifying liquid waste received from the particulate separation unit using a purification assembly; and processing syngas generated from solid waste processed by the heating unit using a syngas processing unit.

Preferably, the method comprises drying the wet solid matter received from the separator using a dryer. Preferably, the dryer is connected in flow communication to a pyrolizer.

Optionally, the purification assembly comprises any one or a combination of: at least one liquid distillation unit to at least partially vapourise and condense the liquid waste; a chemical treatment unit to chemically treat and pasteurise the liquid waste; an electromagnetic radiation unit to irradiate and pasteurise the liquid waste; a heating unit to heat the liquid waste at and/or above a pasteurisation temperature to pasteurise the liquid waste; a bio-treatment unit to biologically treat and pasteurise the liquid waste.

Optionally, the method comprises: receiving the syngas at a syngas chamber; allowing a supply of air into the syngas chamber to mix with the syngas; cooling and at least partially condensing the syngas and/or a mixture of air using a syngas heat transfer unit; and filtering the condensate generated by the heat transfer unit to at least partially remove oil from the condensate.

Preferably, the method comprises processing syngas generated from solid matter processed by the heating unit using a syngas processing unit having a syngas combustion unit to combust syngas generated from the heating unit.

Optionally, the method comprises cooling the syngas at the processing unit using a liquid chamber to receive a liquid and a syngas chamber to receive syngas generated from the solid matter processed by the heating unit. Optionally, the method comprises condensing the syngas and/or a mixture of air using a syngas a heat transfer unit. Optionally, the method comprises filtering a syngas condensate using a filter to remove oil from the syngas condensate. Preferably, the method comprises transporting liquid waste from the separator to a solid settlement tank and collecting sludge from the solid settlement tank at a sludge tank. Preferably, the method comprises transporting liquid waste from the solid liquid settlement tank to a liquid treatment control tank.

Preferably, the method comprises filtering liquid waste using a first toilet waste filter and a second toilet waste filter.

Preferably, the method comprises processing sink liquid waste using a sink waste processing unit having a sink liquid waste tank and a sink liquid waste filter.

Optionally, the method comprises vaporising waste liquid within a toilet waste vapourisation tank and a sink waste vapourisation tank; and condensing vapour generated from the toilet waste vapourisation tank and the sink waste vapourisation tank using a condenser/heat exchanger; and collecting condensate from the condenser/heat exchanger at a sink waste reservoir tank and a toilet waste reservoir tank.

Preferably, the method comprises supplying a flow of purified liquid from the purification assembly to a conduit network connectable to a toilet and/or a sink.

Preferably, the method comprises processing syngas generated by the heating unit using a syngas processing unit comprising: mixing air and syngas at an air-syngas mixer. Optionally the method comprises combusting the syngas-air mixture at a combustion chamber; and collecting biochar generated from the combustion of the syngas at a biochar collection tank.

Optionally, the heating unit is configured to provide the initial drying function and then to provide the higher temperature thermal decomposition of the solid waste via pyrolysis.

Reference to pyrolysis herein encompasses a chemical degradation process that occur at higher temperatures (i.e., above the boiling point of water or other solvents) and differs from combustion as it does not involve the addition/presence of oxygen. The ‘pyrolysis’ process as described herein produces solids (char), condensable liquids (tar) and product gasses referred to herein as syngas. Syngas as described herein typically includes carbon monoxide (CO), carbon dioxide (CO2), hydrogen (H2), methane (CH4), water vapor/steam, sulphur and other compounds.

Optionally the apparatus comprises a dryer unit and a heating unit connected to enable transfer of waste from the dryer to the heating unit. Optionally the apparatus comprises a plurality of drier and/or a plurality of heating units arranged in parallel and/or in series.

Optionally the present apparatus comprises a plurality of solid and liquid storage tanks where reference within this specification to ‘a’ tank encompassing ‘a plurality’ of such tanks arranged in series or in parallel as needed, depending on volumes of solid-liquid waste to be processed.

According to a one aspect of the present invention there is provided human waste processing apparatus comprising: a solid-liquid waste receiver/ separator having an inlet connectable in fluid communication to a toilet, at least one outlet; and a heating unit having a heating unit inlet connectable to the outlet of the separator.

Optionally, the receiver comprises a receiving tank for the mixed solid-liquid waste. Optionally, the apparatus comprises a predominantly solid matter outlet and a predominantly liquid matter outlet. Preferably, the apparatus comprises an evacuation unit to at least partially evacuate the receiver/ separator and/or the receiving tank.

Preferably the apparatus comprises a heating unit coupled to the at least one outlet to heat the mixed solid-liquid waste and provide separation of the solid and liquid waste via at least distillation of the liquid waste. Preferably, the receiver/separator, the receiving tank and the heating unit are maintainable under partial vacuum.

According to a one aspect of the present invention there is provided human waste processing apparatus comprising: a solid-liquid separator having a separator inlet connectable in fluid communication to a toilet, a predominantly solid matter outlet and a predominantly liquid matter outlet; and optionally a heating unit having a heating unit inlet connectable to the solid matter outlet of the separator.

According to a further aspect of the present invention there is provided a method of processing human waste comprising: transferring mixed solid and liquid human waste from a toilet to a solid-liquid separator having a separator inlet connectable in fluid communication to the toilet, a predominantly solid matter outlet and a predominantly liquid matter outlet; separating the mixed solid and liquid waste into predominantly solid matter and predominantly liquid matter via the solid-liquid separator.

Preferably, the method comprises transferring the predominantly solid matter to a heating unit; and decomposing the predominantly solid matter within the heating unit.

Optionally, the method comprises processing syngas generated from the solid matter by the heating unit via a syngas processing unit. Optionally, the step of processing syngas via the syngas processing unit comprises combusting the syngas when mixed with air and/or oxygen.

Optionally, a step of filtering toilet waste liquid via a waste liquid filtration unit comprises: filtering the toilet waste liquid via a first toilet waste filter having a microscale filtration membrane and filtering the toilet waste liquid via a second toilet waste filter having a nanoscale filtration membrane.

Optionally, the method comprises sterilising toilet waste liquid via a wastewater purification unit connectable in fluid flow communication with the toilet waste liquid filter. Optionally, the method comprises transferring the toilet waste liquid to the wastewater purification unit via the sink wastewater filter.

Optionally, the purification unit further comprises: a toilet waste reservoir tank coupled in fluid communication to the toilet waste vapourisation tank via the heat exchanger to receive and store condensate generated from vapourisation of liquid within the toilet waste vapourisation tank; and the purification unit further comprises a sink waste reservoir tank coupled in fluid communication to the sink waste vapourisation tank via the heat exchanger to receive and store condensate generated from vapourisation of liquid within the sink waste vapourisation tank. Optionally, the method comprises: returning a flow of purified water to the toilet and/or the sink via an outlet of the toilet waste reservoir tank coupled in fluid communication to a toilet and/or a sink to provide a return flow of purified water to the toilet and/or the sink; and/or returning a flow of purified water to the toilet and/or the sink via an outlet of the sink waste reservoir tank coupled in fluid communication to a toilet and/or a sink to provide a return flow of purified water to the toilet and/or the sink.

Optionally, the method comprises processing syngas output from the heating unit via a syngas processing unit connected in fluid communication with the heating unit. Optionally, the step of processing the syngas output from the heating unit via the syngas processing unit comprises: mixing a flow of syngas from the heating unit with air and/or oxygen via an air-syngas mixer having an air intake to produce a syngas-air mixture.

Optionally, the method comprises: transferring predominantly liquid waste from the predominantly liquid matter outlet of the separator to a solids settlement tank; allowing a sludge to settle within the solids settlement tank and transferring the sludge to a sludge tank connected in fluid flow with the solids settlement tank; transferring waste liquid from an outlet of the solids settlement tank to a liquid treatment control tank; and transferring waste liquid from an outlet of a liquid treatment control tank to a liquid collection buffer tank. Optionally, the method comprises transferring waste liquid from an outlet of the liquid buffer tank to the toilet waste vapourisation tank.

According to a further aspect of the present invention there is provided a transportation vehicle comprising the apparatus as claimed herein, the transportation vehicle comprising any one of: a train; an aircraft; a marine vessel; a road vehicle such as a coach, lorry or wagon. According to a further aspect of the present invention there is provided a separator for separating mixed solid and liquid human waste comprising: a rotatable drum having a drum inlet to receive mixed solid and liquid human waste, the drum having an internal chamber; a mesh screen mounted within and extending at least partially across the internal chamber; the drum having a predominantly liquid matter outlet and a separate predominantly solid matter outlet.

Optionally, the separator comprises at least one mechanical actuator to rotate the drum about a rotational axis between a first position to open the drum inlet and close the predominantly solid matter outlet and a second position to close the drum inlet and open the predominantly solid matter outlet.

According to a further aspect of the present invention there is provided a method of separating mixed solid and liquid human waste comprising: transporting mixed solid and liquid human waste from a toilet to a solid-liquid separator; receiving the mixed solid and liquid human waste at an inlet of a rotatable drum; transferring the mixed solid and liquid human waste from the inlet to a mesh screen mounted within an internal chamber of the drum; separating and collecting at the mesh screen predominantly solid matter whilst allowing predominantly liquid matter to flow through the mesh screen and towards a predominantly liquid outlet; rotating the drum about a rotational axis to transfer the predominantly solid matter to a predominantly solid matter outlet.

According to a further aspect of the present invention there is provided a transportation vehicle comprising the separator as claimed herein, the transportation vehicle comprising any one of: a train; an aircraft; a marine vessel; a road vehicle such as a coach, lorry or wagon.

According to a further aspect of the present invention there is provided apparatus to process predominantly solid human waste comprising: a dryer having a dryer inlet to receive predominantly solid human waste and a dryer outlet to output dried human waste; a pyrolysis unit having a heating chamber and a heater, the heating chamber having a chamber inlet connected to the dryer outlet, a chamber solid matter outlet and a chamber gas outlet.

Preferably, the apparatus further comprises a syngas collection unit connected to the first chamber gas outlet to collect syngas generated by the pyrolysis unit.

Optionally, the apparatus comprises a syngas combustion unit to combust the syngas collected by the syngas collection unit and having an air or oxygen inlet port, the syngas combustion unit positioned proximate to the second heating chamber and configured to direct heat energy resultant from the combustion of the syngas to the second heating chamber.

Optionally, the apparatus comprises a second stage pyrolysis unit having a second heating chamber and a second heater, the second heating chamber having a second chamber inlet connected to the first heating chamber outlet.

According to an further aspect of the present invention there is provided a method of processing predominantly solid human waste comprising: drying predominantly solid human waste in a dryer to create dried solid waste; transferring the dried solid waste to a dryer or pyrolysis unit having a chamber and a heater; drying and/or thermally decomposing the dried solid waste within the dryer or pyrolysis unit to create partially dried and/or thermally decomposed solid waste; optionally collecting syngas generated by the step of drying or decomposing the dried solid waste at a syngas collection or processing unit.

Optionally the method comprises thermally decomposing the solid waste within a pyrolysis unit optionally using heat energy generated from a combustion of the syngas collected by the syngas collection unit to create fully decomposed waste char.

According to a further aspect of the present invention there is provided a transportation vehicle comprising the apparatus as claimed herein, the transportation vehicle comprising any one of: a train; an aircraft; a marine vessel; a road vehicle such as a coach, lorry or wagon.

According to a further aspect of the present invention there is provided human waste processing apparatus comprising: a solid waste processing arrangement connectable to the a toilet optionally via a solid-liquid waste separator and having a heating unit to at least partially dry solid waste received a toilet; a syngas processing unit to process syngas generated from the solid matter processed by the heating unit, the syngas processing unit comprising: a syngas chamber to receive the syngas; an air inlet port to allow a supply of air into the syngas chamber to mix with syngas; a heat transfer unit to cool and at least partially condense the syngas and/or a mixture of air the syngas; and a filter to filter the condensate generated by the heat transfer unit and to at least partially remove oil from the condensate.

According to a further aspect of the present invention there is provided human waste processing apparatus comprising: a solid-liquid separator connectable in fluid communication to a toilet; a solid waste processing arrangement coupled to an outlet of the separator and having a heating unit with a heating chamber to heat and/or thermally decompose at least the solid waste received from the separator.

Optionally, the apparatus comprises a gas supply reservoir to supply an inert gas to the heating unit. The inert gas used during the pyrolysis processes as descried herein creates an oxygen free environment within the pyrolysis chamber. The inert gas may comprise steam, carbon dioxide, hydrogen etc.

Optionally, the apparatus comprises an evacuation unit to create at least a partial vacuum within the heating chamber and/or the solid-liquid separator. Reference to ‘separator’ as used here encompasses other terms such as a ‘solid-liquid waste transfer unit’ or ‘solidliquid waste transfer valve’. Such a unit/valve is configured to transfer mixed solid and liquid waste to a heating unit. Optionally, the apparatus comprises a liquid waste processing arrangement coupled to a liquid matter outlet and having at least one particulate separation unit to separate solid particulate from liquid waste received from the separator.

Optionally, the apparatus comprises a purification assembly coupled to the liquid waste processing arrangement to sterilise the liquid waste received from the liquid waste processing arrangement.

Optionally, the apparatus comprises a syngas processing unit coupled to the heating unit to process syngas generated from solid waste processed by the heating unit.

According to a further aspect of the present invention there is provided human waste processing apparatus comprising: a solid-liquid separator having at least one outlet (optionally a predominantly solid matter outlet and a predominantly liquid matter outlet); a solid waste processing arrangement coupled directly or indirectly to the outlet (optionally the solid matter outlet) and having a heating unit; a liquid waste processing arrangement coupled to the outlet (optionally the liquid matter outlet); a purification assembly coupled to the liquid waste processing arrangement; and a syngas processing unit coupled to the heating unit.

According to a further aspect of the present invention there is provided human waste processing apparatus comprising: a syngas processing unit coupled to a heating unit to heat and/or thermally decompose solid waste received from a waste input, the syngas processing unit configured to process syngas generated from solid waste processed by the heating unit and comprising: a syngas chamber to receive the syngas; an air inlet port to allow a supply of air into the syngas chamber to mix with syngas; a heat transfer unit to cool and at least partially condense the syngas and/or a mixture of air and the syngas; and optionally a filter to filter the condensate generated by the heat transfer unit and to at least partially remove oil from the condensate.

According to a further aspect of the present invention there is provided human waste processing apparatus comprising: a syngas processing unit connectable to a heating unit to heat and/or thermally decompose solid waste received from a waste input such as a toilet or other human waste input device or arrangement, the syngas processing unit configured to process syngas generated from means to heat and/or thermally decompose solid waste, optionally via a pyrolysis process, the syngas processing unit comprising: a syngas chamber to receive the syngas.

Preferably, the apparatus comprises an air inlet port to allow a supply of air into the syngas chamber to mix with syngas. Optionally, the apparatus comprises an arrangement to cool and at least partially condense the syngas and/or a mixture of air and the syngas.

Preferably, the apparatus comprises a filter to filter the condensate generated by the heat transfer unit and to at least partially remove oil from the condensate.

Optionally, the apparatus comprises a solid-liquid separator/transfer valve connectable in fluid communication to a toilet, and having at least one outlet and optionally a predominantly solid matter outlet and a predominantly liquid matter outlet.

Optionally, the apparatus comprises a solid waste processing arrangement coupled to the solid matter outlet and having a heating unit with a heating chamber to heat and/or thermally decompose solid waste received from the separator and an evacuation unit to create at least a partial vacuum within the heating chamber.

Optionally, the apparatus comprises a liquid waste processing arrangement coupled to liquid matter outlet and having at least one particulate separation unit to separate solid particulate from the liquid received from the solid-liquid separator. Optionally, the apparatus comprises a purification assembly coupled to the liquid waste processing arrangement to sterilise the liquid waste received from the liquid waste processing arrangement.

According to a further aspect of the present invention there is provided human waste processing apparatus comprising: a solid-liquid separator/transfer unit/valve to separate and/or transfer waste matter, the separator/transfer unit/valve connectable in fluid communication to a human waste input device (such as a toilet); a purification assembly coupled to the separator/transfer unit/valve to sterilise waste (optionally predominantly liquid waste) received from the separator/transfer unit/valve; and optionally a syngas processing unit coupled to the separator/transfer unit/valve to process syngas generated from solid waste processed by the separator/transfer unit/valve.

Optionally, the solid-liquid separator is a heating unit to provide solid and liquid phase separation via liquid distillation. Optionally the solid-liquid separator is a mechanical separator to provide solid and liquid phase separation via at least one filter, mesh, screen and/or valve. Optionally, the purification assembly comprises at least one output connectable to a processed liquid conduit network to provide a supply of liquid processed by the purification assembly.

Optionally, the purification assembly comprises any one or a combination of at least one liquid distillation unit to at least partially vapourise and condense the liquid waste; a chemical treatment unit to chemically treat and pasteurise the liquid waste; an electromagnetic radiation unit to irradiate and pasteurise the liquid waste; a heating unit to heat the liquid waste at and/or above a pasteurisation temperature to pasteurise the liquid waste; a bio-treatment unit to biologically treat and pasteurise the liquid waste.

Optionally, the liquid distillation unit comprises a toilet waste vapourisation tank connectable in fluid communication to a toilet waste liquid filter and a sink waste vapourisation tank connectable to a sink liquid waste filter. Optionally, the purification assembly comprises a vapourisation unit having a heating unit provided at each of the toilet and sink vapourisation tanks to vaporise liquid within said tanks.

Optionally, the purification assembly further comprises a heat exchanger unit having: a heating coil; a liquid circulation tank provided in fluid communication via a conduit manifold to the coil; a circulation unit to drive a fluid circulation through the heating coil and the liquid circulation tank.

Optionally, the purification assembly further comprises: a toilet waste reservoir tank coupled in fluid communication to the toilet waste vapourisation tank via the heat exchanger unit to receive and store condensate generated from vapourisation of liquid within the toilet waste vapourisation tank; and the purification assembly further comprises a sink waste reservoir tank coupled in fluid communication to the sink waste vapourisation tank via the heat exchanger unit to receive and store condensate generated from vapourisation of liquid within the sink waste vapourisation tank. Optionally, an outlet of the toilet waste reservoir tank is coupled in fluid communication to a toilet and/or a sink to provide a return of purified liquid to the toilet and/or the sink; and/or an outlet of the sink waste reservoir tank is coupled in fluid communication to a toilet and/or a sink to provide a return of purified liquid to the toilet and/or the sink.

According to a further aspect of the present invention there is provided apparatus to process predominantly solid human waste comprising: a separation unit having an internal chamber with an inlet to receive mixed solid and liquid human waste, a solid waste outlet to output predominantly solid waste from the chamber, a liquid waste outlet to output liquid phase waste and/or gas phase waste from the chamber, a heater to heat the internal chamber and the mixed solid and liquid waste to provide at least distillation of the liquid waste and separation from the predominantly solid waste.

According to a further aspect of the present invention there is provided a human waste processing apparatus comprising: a solid-liquid separator unit connectable in fluid communication to a toilet to receive mixed solid and liquid waste, the separator unit having a heater and a heating chamber to heat the mixed solid and liquid waste and provide at least distillation of the liquid waste, a predominantly solid matter outlet and a liquid matter and/or gas matter outlet; and a syngas processing unit coupled to the separator unit to process syngas generated from heating at least the solid waste within the heating chamber.

According to the further aspect, solid-liquid matter separation is achieved via liquid distillation using a heating unit. In particular, liquid and gas phase matter is separated from the solid phase matter by heating the mixed liquid and solid waste within a heating unit/chamber, as described herein. The liquid distillate may then be collected at a liquid collection reservoir together with the product gases. The concept is configured for heating of mixed solid-liquid waste by pyrolysis and/or torr efaction and specifically by avoiding combustion (involving the presence of oxygen).

The present concept may be implemented with a solid-liquid separator and/or heating unit having a respective internal chamber(s) that may be maintained at a partial vacuum or an inert gas may be introduced and maintained within the internal chamber(s). The apparatus comprises a suitable evacuation unit (that may be implements as a pump or venturi valve connected to a receiving tank (that feeds the separator or heating unit) and/or the separator and/or the heating unit. The apparatus is configured such that the internal chamber of the heating unit is substantially devoid of oxygen to specifically avoid combustion within the internal chamber during heating. Solid matter separated from the liquid and gas phase matter may then be removed from the heating unit using the apparatus as described for example using a screw conveyor to transport the solid matter from within the internal chamber. The liquid and pyrolysis product gases (syngas) may then be transported onward through the system. Optionally, the liquid distillate may be filtered via one or more chemical or biological filters to remove particulates and/or pathogens, toxins, microbes, bacteria etc. Additionally, the liquid distillate may be filtered through suitable filters, such as charcoal or activated carbon filters to remove odour and/or colouration of the liquid prior to returning/ delivering the liquid distillate for reuse to a sink or toilet. The product syngas from the liquid distillation (separated from the solid matter) may then be processed according to the syngas processing unit as described. In particular, the syngas may be processed by mixing with air and then the air syngas mix condensed (condensation of the product syngas constituents with liquid/water vapour). The condensed water-syngas constituent liquid mixture may then be filtered, as described, to remove particulates and/or pathogens, toxins, microbes, bacteria etc.

Additionally, the liquid phase distillate (generated from the pyrolysis heating at the heating unit) may be filtered through suitable filters, such as charcoal or activated carbon filters so as to remove odour and/or coloration of the liquid prior to returning/ delivering the liquid distillate for reuse to a sink or toilet. According to the further aspect, the apparatus utilising a heating unit to provide solidliquid phase separation, via distillation, may comprise one or a plurality of suitable airtight waste transfer valve(s) that may be actuated to close at the input and/or output side of the heating unit so as to maintain a partial vacuum within the internal chamber. Optionally, the airtight waste transfer valve may comprise the solid-liquid separator as described herein in which a solid-liquid mixture is delivered into the solid-liquid separator via an input tank and then predominantly solid and predominantly liquid waste may then be output at one or a plurality of output(s). According to the further aspect, the liquid output of the mechanical solid-liquid separator may comprise a shut off valve at the liquid outlet to prevent onward flow of liquid through this outlet and direct all of the solid and liquid waste exclusively through the solid waste outlet. Accordingly, in this aspect, and in this mode of operation, with the liquid waste outlet of the solid-liquid separator closed, it is only the predominantly solid outlet that provides input into the heating unit for distillation and in particular solid-liquid phase separation.

According to a further aspect the heating unit may comprise or be connectable with a source (canister, reservoir, tank) of an inert gas to provide a substantially oxygen free environment within the heating chamber. The inert gas may comprise carbon dioxide, carbon monoxide, argon, nitrogen, etc.

The apparatus may comprise one or a plurality of heating units connected in parallel or in series to provide the phase separation and in particular liquid distillation. The heating unit may comprise suitable valves and temperature sensors to provide fractional distillation of the mixed solid-liquid waste to collect separately the different constituents of the solidliquid waste as they distil at their respective vapourisation/boiling temperatures. The apparatus may comprise a plurality of distillate collection reservoirs/tanks and/or valves to collect separately the different constituents.

Brief description of drawings

A specific implementation of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which: Figure 1 illustrates schematically a train having a wastewater treatment/processing system configured to process both sink and toilet water including both liquid and solid phase matter;

Figure 2 is a schematic flow diagram of the various steps of a sink and toilet wastewater processing system according to a first specific implementation;

Figure 3 is a perspective view of a solid-liquid separator to receive and process wastewater according to a specific implementation;

Figure 4 is a magnified perspective view of a rotatable drum part of the separator of figure 3 with various components removed for illustrative purposes;

Figure 5 is a cross sectional perspective view of the separator of figure 3 through A-A with various components removed for illustrative purposes;

Figure 6A is a cross sectional perspective view of parts of the wastewater treatment system from a first side comprising the separator of figure 3 and a Dryer and pyrolizer, in-series according to a specific implementation;

Figure 6B is a cross sectional perspective view of parts of the wastewater treatment system from a second side comprising the separator of figure 3 and a Dryer and pyrolizer, in-series according to a specific implementation;

Figure 7 illustrates schematically a wastewater treatment system and flow diagram of some initial stages of a liquid and solid waste separation and processing arrangement according to the first specific implementation;

Figure 8 illustrates schematically a wastewater treatment system and flow diagram of some further stages of the liquid and solid waste separation, filtration and processing subsequent to the waste processing of the flow diagram of figure 7 according to the first specific implementation;

Figure 9 illustrates schematically a wastewater treatment system and flow diagram of some further stages of the liquid and solid waste separation, filtration and processing subsequent to the waste processing of the flow diagram of figure 8 according to the first specific implementation;

Figure 10 illustrates schematically a wastewater treatment system and flow diagram of some purification and final stages of the liquid waste processing subsequent to the waste processing of the flow diagram of figure 9 according to the first specific implementation;

Figure 11 illustrates schematically a waste treatment system and flow diagram of some initial stages of a solid waste separation, heating and processing arrangement according to the first specific implementation;

Figure 12 illustrates schematically a waste treatment system and flow diagram of some final stages of a solid waste heating, pyrolysis and processing arrangement subsequent to the waste processing of the flow diagram of figure 11 according to the first specific implementation;

Figure 13 is a schematic flow diagram of the various steps of a sink and toilet wastewater processing system according to a second specific implementation;

Figure 14 illustrates schematically a wastewater treatment system and flow diagram of some initial stages of a liquid and solid waste separation and processing arrangement according to the second specific implementation;

Figure 15 illustrates schematically a wastewater treatment system and flow diagram of some initial stages of a liquid and solid waste separation and processing arrangement according to the second specific implementation and subsequent to the waste processing of the flow diagram of figure 14; Figure 16a illustrates schematically a wastewater treatment system and flow diagram of some purification and initial stages of the liquid waste processing system subsequent to the waste processing of the flow diagram of figure 15 according to the second specific implementation;

Figure 16b illustrates schematically a wastewater treatment system and flow diagram of some final purification stages of the liquid waste processing system subsequent to the waste processing of the flow diagram of figure 16b according to the second specific implementation;

Figure 17a illustrates schematically a waste treatment system and flow diagram of some initial stages of a solid waste heating and processing arrangement according to the second specific implementation and subsequent to the waste processing and solid-liquid separation stages of the flow diagram of figure 14;

Figure 17b illustrates schematically a waste treatment system and flow diagram of some final stages of a solid waste heating, pyrolysis and processing arrangement and subsequent to the waste processing of the flow diagram of figure 17a according to the second specific implementation;

Figure 18 illustrates schematically a waste treatment system and flow diagram of some final stages of a waste processing arrangement as part of a discharge processing of the waste according to the second specific implementation;

Figure 19 illustrates schematically of a waste treatment system and flow diagram of some initial stages of collection and delivery of mixed solid-liquid waste for delivery to a heating still to separate solid and liquid phases via distillation according to a further specific embodiment. Detailed description of preferred embodiment of the invention

A human waste treatment system is provided configured to process a variety of different types of waste including in particular human waste (including faeces and urine) and toilet and sink wastewater. The present system, apparatus and method is configured to treat solid waste to provide a form that is harmless, odourless and having a weight/mass that is substantially reduced. Moreover, the present system is adapted for wastewater processing to allow reuse of liquid waste for toilet flush and/or hand washing as appropriate. Outputs from the present system comprise three forms: drinking quality water, inert odourless powdery char and clean exhaust gas.

The present system is adapted for installation, housing or mounting at both static sites, semi-mobile sites and vehicles including for example trains, aircrafts, ships, boats and other vessels, wagons, lorries, couches or other land vehicles. The present system is particularly advantageous for static or mobile instillation and operation where there is no or limited access to a sewage network or human waste processing systems. In particular, the present apparatus and system is particularly adapted for installation internally or externally at a vehicle adjacent a conventional toilet unit. In particular, the present system and apparatus may be installed at an undercarriage region of a train or internally within a water closet (WC) compartment being additional to or attachable to a modular WC unit typically incorporated in a passenger train.

The present apparatus and system provide a self-contained wastewater treatment and water recycling modular arrangement suitable for use at a vehicle such as a train. Energy required for wastewater treatment may be taken from the vehicle. The present system does not require frequent freshwater refilling or frequent solids discharge, that uses special equipment and requires access to main sewerage treatment infrastructure. Toilet and sink waste are treated separately without mixing. Toilet waste is separated into liquid (urine and flush water) and biomass (faeces and paper) before being treated. Sink waste is treated as grey water. Liquid is treated to produce pure distilled water for hand washing and toilet flushing with excess discharged to the rail track. Biomass is treated to produce biochar a carbon rich odourless harmless granular substance that can be used as a fertilizer or fuel and syngas. Syngas, evolved when biomass is reduced by pyrolysis to biochar can be used to recycle energy for liquid treatment or discharged to atmosphere as harmless exhaust gas.

Referring to figure 1, a train 10 for driven transport along a track 13 comprises an internal water closet (WC) unit (not shown) having a conventional toilet 11. The present waste processing system and apparatus 12 is mounted externally of the passenger compartment region and is optionally attached to an undercarriage of the train 10 immediately adjacent the outflow of the WC including outflow from toilet 11 and a suitable sink.

The present system is adaptable to provide different modes of operation as required. For example, in a first mode, sink wastewater may be mixed with toilet wastewater such that the combined liquid waste is processed singularly. Optionally, sink wastewater may be treated separately to toilet wastewater. According to further optional implementations, the sink wastewater may be treated so as to be recycled as toilet flush water and/or returned to the sink as hand washing water. Referring to figure 2, a sink 14 is coupled to a tanking tank 16. According to a first option, sink wastewater is treated separately via process 29 relative to a further option in which the sink wastewater is combined via process 30 with toilet wastewater. In any implementation, sink wastewater may be deposited on the train tracks 13 prior to processing. According to the sink water separate process 29, the wastewater passes 18 through a sink waste filter. The output liquid is then sterilised 22 with the output liquid sink water 26 being recyclable to the sink 14. According to processing option 30, the sink wastewater is processed 19 through a first filter. The output liquid is then fed 23 to and processed by a second filter. The output liquid may be output as flush water 27 or transferred into the toilet waste processing line for purification 22. Flush water 27 may then be returned to toilet 11 and/or deposited on the track 13.

Toilet waste typically referred to as "black waste" is discharged from an on-train toilet system by flushing. The black water is fed to a separator for separation of solid and liquid matter 15. Optionally, liquid waste is then fed 28 to a dirty liquid settlement tank. The dirty liquid or sludge is fed 19 from the settlement tank to the first filter. Part of this dirty liquid or sludge is also fed to the solid processing line to be combined with the solid phase toilet waste separated at stage 15. In particular, the generally solid waste is fed 17 from processing stages 15, 28 into a dryer. The dried solid matter is then fed 21 to a pyrolizer. Syngas 21a output from the pyrolizer is fed 20 to a syngas destruction/combustion unit. Heat resultant from the syngas destruction operation is returned 21b to the pyrolizer to provide an energy efficient solid matter processing system. Syngas destruction unit is fed with a constant supply of air 20a. A vacuum unit and processing utility 20b drive safe gas emissions 24 to be vented from the system. Pyrolizer outputs processed solids 25 as char. Heat energy generated from the pyrolizer is fed 21c to the purification unit and process 22 configured to receive 23 the liquid from the second filter. Purification unit and process 22 is also configured to receive sink wastewater via sink waste filter. Additionally, solids output from the dryer (17) may be processed through a vapour filter between units and processors 17, 21 to be combined 19 with the liquid flow between first and second filters.

Referring to figures 3 to 5, a solid-liquid separator 31 comprises a primary waste receiving tank 32 in the form of an elongate trough having respective first and second lengthwise ends 33, 34. Separator 31 is configured as an airtight transfer valve to transfer solid and liquid waste (under partial vacuum) to the heating unit (dryer 152, pyrolizer 164) so as to avoid oxygen being present within a heating chamber of the heating unit. Trough comprises a suitable containment lid (not shown) having an inlet port 194 (illustrated in figure 6B). A rotatable drum 35 is mounted in a suspended position immediately below trough second end 34. Drum 35 is mounted to trough via a bracket and an axel extending centrally through drum 35 to allow rotation about axis 40. Actuation of the rotation of drum 35 is provided by linear actuators 36 having extendable and retractable rams 39. The distal end of rams 39 is mechanically attached respectively to each lateral side face of an annular (disc-shaped) side walls of drum 35 via eyelet mounts 38. A slot 43 within the trough base towards second end 34 provides fluid flow communication into the interior of drum 35 such that liquid and solid matter can flow from trough via slot 43 into an upper chamber 41 of drum 35. In particular, an internal region of drum 35 is divided into first upper chamber 41 and a second lower chamber 42 via a mesh plate 44 extending fully across the drum internal region. Both chambers 41 and 42 may be maintained under partial vacuum (via the evacuation unit 60) to exclude oxygen within the separator 31 and importantly avoid oxygen being fed to the heating unit (152, 164). A slide plate 45 is mounted immediately below and at an inclined angle relative to mesh plate 44. Inclined plate 45 is attached a lowermost end to a tube 37a extending centrally through drum 35 along axis 40. Tube 37a comprises receiving apertures 37c to allow liquid to flow over inclined plate 45 and into tube 37a towards an outlet 37b (provided at one end of tube 37a). Outlet 37b is adapted to allow an outflow of waste liquid from the separator 31. Drum 35 also comprises a waste solid matter outlet 46 provided at a lower region of drum 35 in an opposite half relative to slot 43. Accordingly, mixed "black’ waste may be deposited within tank 32 that delivers the solid-liquid mixed matter via an inclined base surface into drum 35 via slot 43 under gravity, with the separator 31 controlled in an "open ’ position. Biomass (faeces, paper and bound liquid) is retained within drum 35 and in particular within chamber 41 on mesh plate 44 whilst waste liquid is routed through the mesh 44, onto plate 45 and into outflow tubing 37a and liquid outlet 37b. This waste liquid is then fed to a liquid treatment control tank via a solids settlement tank, described in more detail referring to figures 7 and 8. Collected solid biomass is retained at the straining screen 44 within chamber 41 as the liquid is drained via outlet 37b. Drum 35 is then rotated/oscillated a pre-set number of times by linear actuators 36 to pivot plate 44 to alignment with solid mass outlet 46 to allow the solid biomass to slide downwardly and out of the separator 31.

Referring to figures 6 A and 6B, the present waste treatment apparatus is advantageously constructed as a self-contained module for attachment and/or installation at a site or vehicle. The present apparatus 12 may be regarded as modular and comprises a frame or housing (not shown) with sufficient structural integrity to contain all working parts of the apparatus and system. In particular, the system further comprises a plurality of waste treatment and storage tanks including a solid settlement tank 73; a sludge tank 74; a liquid treatment control tank 78; a buffer tank 107; a vapourisation tank (sink) 196; a vapourisation tank (flush) 195; a syngas/air venturi mixer and gas/air combustion chamber 175 (figure 12) ; a cooling water recirculation tank 122 having an internal cooling water recirculation pump 121; a sink wastewater tank 98; a flush water tank 130; and a sink water tank 140. Tanks 196, 195, 122, 130 and 140 are coupled in fluid communication with a condenser (heat exchanger 110). The apparatus further comprises a stage 1 micro filter 82 and a stage 2 nano filter 104 to provide respective filtration of the wastewater as part of the water treatment process. The liquid processing system further comprises a circulation pump 85 coupled in fluid communication with the respective filters 82, 104 as part of the liquid processing network.

Referring to figure 6B, the apparatus further comprises a dryer 152 formed as an elongate chamber having an external heating tape applied externally and extending longitudinally between respective first and second lengthwise ends 50, 51 of dryer 152. A screw transport actuator (not shown) is mounted internally within dryer 152 and powered by a servo-motor and controller 165, that by rotation about a longitudinal axis is configured to transport solid matter from first end 50 to second end 51. Dryer 152 may be implemented at temperatures in the region 50-150°C to dry the waste solid matter transported between ends 50, 51. Suitable insulation material is provided externally around the external heating tape to ensure the outer surface of dryer 152 does not exceed a pre-set temperature of for example 80°C. A flow coupling 47 provides a conduit link between separator solid matter outlet 46 and dryer first end 50 such that solid matter may be deposited directly into dryer 152 from separator drum 35.

The apparatus further comprises a pyrolizer 164 also in the form of an elongate tube having respective first and second lengthwise ends 53, 54. Pyrolizer 164 similarly comprises external heating tape extending around the main tubular body that is covered externally via an insulation material. Pyrolizer 164 comprises according to the preferred implementation, twin counter rotating screw actuators (not shown) extending between ends 53, 54 to transport partially dried waste solid matter between ends 53, 54. The screw actuators (not shown) are powered by a servo-motor and controller 165. Pyrolizer first end 53 is coupled to dryer second end 51 via a coupling 52 (that incorporates an air-tight transfer valve 157, figure 11 and 12). Similarly, a conduit coupling 55 is provided at pyrolizer second end 54 to provide on-flow of the processed solid matter. Pyrolizer 164 further comprises a temperature transmitter 169 (figure 12) and a pressure transmitter 168 (figure 12) towards the cooler inlet axial end and a temperature transmitter 151 (figure 11) positioned at the hotter discharge end.

Apparatus 12 further comprises an excess liquid discharge manifold 192 and a biochar collecting chamber 193 to receive the processed solid matter from pyrolizer 164 in the form of mass-reduced char as a product of the waste solid treatment process. The apparatus of figures 6 A and 6B is controllable via one or a plurality of control modules comprising or interfacing with suitable electronics and software. In particular, a control unit 198 includes a combustion control system to control pyrolizer 164 and/or dryer 152. The control unit is further configured to control electronically the various electromechanical, electropneumatic and electrohydraulic components of the present apparatus including in particular operation and control of valves, pumps, heating units, condensers, heat exchangers, pipe network flow conduits including through-flow valves, exhaust valves directional flow control valves etc as will be appreciated. Such control electronics, software and communication comprise components and software architectures to provide both local and remote control and monitoring of the present waste treatment system.

The architecture and operational function of the present wastewater treatment system is described referring to the processing flow diagrams of figures 7 to 12 and with specific reference to an example installation and utilisation on a train carriage forming part of a toilet and sink water closet (WC) module. The present system is configured to collect toilet and sink waste for storage in dedicated tanks. In particular, sink waste and toilet waste are collected in respective first and second tanks for onward processing with the toilet and sink waste treated separately without mixing. The present system is adapted to separate toilet waste into liquid (urine and flush water) and biomass (faeces and paper) before treatment. Sink waste is treated as ‘grey water ’ the present apparatus is configured for the treatment of liquid waste to produce substantially pure distilled water for hand washing and toilet flushing with any excess discharged from the system or for example onto the rail tracks. Biomass is treated to produce biochar being a carbon rich, odourless and harmless granular substance for use as a fertilizer, fuel or syngas. Syngas evolved as part of the process of biomass reduction via a pyrolizer can be used to recycle energy for liquid treatment or discharged to atmosphere as a harmless exhaust gas.

Referring to figure 7, sink 14 having a tap 56 creates sink waste (grey water) 58. A toilet 11 provided with a flush mechanism 57 is connected to an inlet shut-off valve 59 configured to isolate waste receiving tank 32 from the toilet discharge. A float type level switch 61 is connected to tank 32 to provide a fault signal to PLC to control the system when the wastewater receiving tank 32 is full. A venturi (vacuum) valve 60 is connected to a pressure regulator 66 that is in turn coupled to the waste receiving tank 32.

Accordingly, valve 60 is configured to create a partial vacuum at (and/or positive pressure may be applied to) receiving tank 32 to create a partial vacuum (and/or apply a positive pressure to) at tank 32 and separator 31. The waste receiving tank 32 is further provided with a pressure transmitter 48. Separator 31, as described, comprises a waste liquid outlet flow 62 and a waste solid outlet flow 63. The solid biomass waste is then transferred and processed via the solid mass processing apparatus and method 64 being described referring to figures 11 and 12. The liquid processing of flow 62 is described referring to figures 8 to 10. As illustrated in figure 7, the vacuum blow-off valve (evacuation unit) configured to generate the positive or negative pressure at the receiving tank 32 is connected to a biochar collecting chamber 193 which is in turn vented to atmosphere 65.

Referring to figure 8, a solid settlement tank 73 is fed directly by the liquid flow 62 from separator 31. Tank 73 is provided with a sludge tank 74 at a lower region thereof. An overflow conduit 68 couples tank 73 to a liquid treatment control tank 78 having a breather valve 76. A settle liquid transfer valve 75 provides a further coupling between tanks 73 and 78. A level transmitter 77 is connected to liquid treatment control tank 78. Tank 78 and in particular, an outlet of tank 78 is connected to a circulation pump 85 for the onward flow of liquid to a primary filter 82 via intermediate orifice plate 84 and a suitable spring- loaded non-return valve 83. The stage 1 filter 82 is configured for the micro separation of filtered settled liquid and adapted to remove suspended solids via a micro membrane and is provided with a pressure transmitter/ sensor 81. A first output of the filter 82 is directed as a return to the solid settlement tank 73 via an actuated radial diaphragm valve 69 with a separate parallel line between filter 82 and tank 73 routed via a lockable diaphragm control valve 70. Filter 82 is further provided with a pressure transmitter to monitor cross flow pressure. The lower region of solid settlement tank 73 and the sludge tank 74 are coupled in fluid communication via an actuated radial diaphragm valve 80 acting as a sludge isolation valve. A pre-set vacuum regulated breather 72 is also provided at sludge tank 74 to allow air flow into the tank 74. Sludge tank 74 is further provided with an outlet coupled to solid waste processing components 64 and in particular dryer 152. A flow transmitter/ sensor 91 monitors the onflow of liquid processed by filter 82.

In the flow direction between circulation pump 85 and orifice plate 84, a pressure transmitter 86 is provided. A further flow line is diverted from the main outlet flow of liquid treatment control tank 78 to the settlement tank 73, at a position between circulation pump 85 and orifice plate 84 via a fixed set point pressure relief safety valve 71.

Referring to figure 9, the waste liquid filtered by the stage 1 filter 82 is directed to flow into a buffer tank 107 via an actuated radial diaphragm isolation valve 92 and spring- loaded non-return valve 94. Tank 107 is further provided with a level transmitter 106 and a pressure transmitter 105. As indicated, tank 107 is coupled in fluid communication to tank 78 via fixed set pressure relief safety valve 95. Tank 107 further comprises a proportional pressure reducing/relieving air pressure pump 93. An outflow of buffer tank 107 is provided to a stage 2 filter 104. Filter 104 comprises a nanomembrane filter to provide a second stage filtration of waste liquid output from tank 107. Filter 104 is coupled to a pressure transmitter 103. A recirculation line extends from filter 104 to tank 107 via a lockable diaphragm flow control valve 102 and a spring-loaded non-return valve 90. Liquid filtered by filter 104 is directed for onward flow via a flow transmitter 108 configured to transmit permeate flow rate to a suitable control PLC.

Still referring to figure 9, sink waste is directed to a sink waste tank 98 via an intermediate non-return valve 88. As with the buffer tank 107, sink wastewater tank 98 is provided with a level transmitter 96 and a pressure transmitter 97. A proportional pressure reducing/relieving air pressure pump 87 is also coupled to tank 98 that is further coupled independently to a fix point pressure relief safety valve 89. An output flow from tank 98 is transferred to a sink wastewater filter reverse flow valve to route waste sink water through a sink filter in reverse flow direction. The valve 99 is accordingly coupled to sink wastewater filter 100 with the corresponding sink wastewater filter reverse flow valve 101 provided at an opposite end.

Referring to figure 10, sink wastewater output from tank 98 and filtered via filter 100 is fed to a vapourisation tank 196. Similarly, a liquid flow from second stage filter 104 (from toilet waste) is fed to a separate vapourisation tank 195 via a flow transmitter 108. Each respective tank 195, 196 is provided with an internal coil and heat source component/chamber 197. Each respective tank 195, 196 is provided with an outlet flow of excess filtered liquid (from either the sink or toilet) to a respective liquid discharge valve 119, 120 coupled respectively to each tank 196, 195. Each of the tanks 196, 195 further comprises a level transmitter 113, 114, a pressure transmitter 112, 115 and a temperature transmitter 111, 117. Valves 119, 120 are provided in communication with a liquid discharge manifold 192. Discharge manifold 192 is configured with an outlet 128 to drain liquid to a rail track, the ground or collection system. Tanks 196, 195 are connected to a condenser/heat exchanger 110 provided with a flow transmitter 109. Condenser 110 is configured to cool steam from the vapourisation tanks 196, 195 to produce distilled water. Accordingly, condenser 110 is coupled in fluid flow with a cooling water recirculation tank 122 that is in turn provided with a cooling water recirculation pump 121, a level transmitter 116 and a temperature transmitter 118. Tank 122 is further coupled to the discharge manifold 192. An inlet of tank 122 is also provided in fluid communication to any one or a combination of the excess liquid/liquid safety valves 123.

A fluid flow outlet from condenser 110 is provide in fluid communication with a flush water collection tank 130 and a separator sink water tank 140 via respective reverse flow non-return valves 149. Each tank 130, 140 receiving the distilled water from condenser 110 is further provided with respective level transmitters 125, 148, pressure transmitters 145, 147 and temperature transmitters 144, 146. Each tank 130, 140 is further provided with a fixed set point pressure relief safety valve 124, 143 and a respective and independent air pressure pump 141, 142. An outlet of each tank 130, 140 is provided in coupled fluid communication to the cooling water recirculation tank 122 via a cooling water make-up valve 129 and a non-return valve 126. In addition, the flow outlets of the each of the flush and sink tanks 130, 140 are routed back to toilet 11 via flush mechanism 57. Each tank 130, 140 is further coupled via flow communication tap work to tap 56 of sink 14 to provide further recirculation of the treated waste liquid. Ref erring to figures 11 and 12, the solid waste processing components and system is described in which wet solid sludge is output as a flow 63 from separator 31 with the separate mainly liquid waste flow 62 being processed via the components and system described referring to figures 7 to 10. The wet solid sludge flows from separator 31 via solid outlet 46 to dryer 152 as described referring to figure 6B. Dryer 152 is coupled to the sludge collection tank 74 via radial diaphragm sludge valve 150 that provides a connection between the sludge tank and the dried 152 and pyrolizer 164. Dryer 152 as described is provided with external helical heating tape 153 between its respective lengthwise ends. Dryer 152 is provided with a temperature transmitter 155 and a pressure transmitter 156 towards the cooler inlet axial end and a temperature transmitter 151 positioned at the hotter discharge end. The outlet flow from Dryer 152 is connected to the pyrolizer 164 via the air-tight transfer valve 157. Dryer 152 and pyrolizer 164 are electrically coupled and controllable via heating controller 158, 159 together with a source of electrical energy 160 that in turn provides the controlled actuation and heating of heating tape 153, 170. Dryer 152 is further coupled to waste discharge manifold 192 via conduits 163 and intermediate air venturi valve 161 and vent valve 154. Valve 161 is configured to extract vapour from the dryer. Referring to figure 10, the vapour is then delivered via a non -return valve to vaporisation tank (flush) 195. An output flow from pyrolizer 164 is directed to the biochar collecting chamber 193 via an intermediate air-tight transfer valve 177 (within coupling 55) to provide the efficient transfer of biochar from the pyrolizer 164 to the biochar collecting chamber 193. Pyrolizer 164 is configured to output a flow of syngas 178, via a gas outflow port. The syngas flow is routed through an air mixing venturi valve 167 to receive air from a suitable source 166. The mixed air and syngas fluid is transferred via a conduit to a zero force non-return valve 182 and a syngas/air venturi mixer mechanism 181. Mixer mechanism 181 transfers the combined gas flow via a pressure transmitter 180 and syngas flow control (non-retum) valve 183 to a combustion control system 176 to ignite and burn the syngas/air mixture to generate heat. Combustion control system 176 is coupled to a downstream gas/air combustion chamber 175 to heat and vapourised sink/flush feed water within liquid vapourisation tanks 195, 196 each having internal emersion heating coils 172, 173 powered by a suitable electrical energy supply 174. An output flow from the gas/air combustion chamber is provided via a suitable conduit network to biochar collecting chamber 193. Chamber 193 is provided with a temperature transmitter 184 and pressure transmitter 185. Char from chamber 193 may be extracted to a biochar extraction point 186. Tank 193 is further provided with a pressure transmitter 187 and an exhaust gas outlet having a corresponding pressure transmitter 190 and an exhaust gas venturi valve 190. The harmless exhaust gas may then be vented to atmosphere 191. As indicated, syngas and the air mixture from syngas/air venturi mixture mechanism 181 may be routed via a non-return valve 183 through conduit 179 to vent to atmosphere 191.

A summary of the liquid wastewater treatment system and corresponding biomass solid treatment system will now be described.

Principle of Operation

With a train in service the present system, in its ‘ready state’ receives wastewater generated by toilet 11 and sink 14 usage. Sink waste is collected and stored in tank 98. Toilet waste is collected in tank 32 that routes liquid waste (urine + flush water) to tank 73 and retains biomass (faeces + paper). When the volume of liquid collected (toilet or sink) reaches a pre-set amount the present system changes to its ‘run state’ and starts wastewater treatment (WWT). Both toilet and sink remain in service when the present system is operating. Toilet waste treatment is split into two systems, liquids and biomass. Each of these systems operate independently and sequentially with a process starting on completion of a previous one. Biomass treatment is initiated by the liquid treatment system. Treatment can only proceed when both systems are ‘ready’.

Waste Liquid Treatment System

Toilet waste liquid is treated by a two stage Membrane Filtration System (MFS). Sink waste is treated by a single stage Filtration System (SFS). Filtered Liquid is routed to Distillation System (LDS) that processes toilet and sink filtered waste Liquids separately. Distilled pure water is routed to two tanks - a flush water storage tank and a sink water storage tank. The flush and sink water tanks are equipped with air pressurisation systems to return water on demand for toilet flushing and hand washing. The LDS operates on demand when either stored flush or sink water volumes fall to a pre-set amount. Heat energy required by the LDS is provided from two sources - an electric thermostatically controlled immersion heater that is always available and syngas combustion that is periodically available. Biomass treatment is initiated after a pre-set number of Liquid treatment cycles.

Biomass Treatment System

Biomass is pre-treated by gravity and pressurised dewatering through separator 31. It is heat treated in dryer 152 with a reduced pressure atmosphere. It is then transferred into the dryer 152 by oscillating separator 31 under elevated pressure. The temperature in dryer 152 is increased. At drying temperature, bound liquid is evolved to vapour and evacuated to atmosphere reducing its weight. Biomass is moved through the dryer 152 using the motorised feed screw exiting into an Air-tight Transfer Valve (157). The ATV transfers the dried Biomass into pyrolizer 164 that operates with a reduced pressure atmosphere and is heated to pyrolizer treatment temperature. Pyrolizer treatment reduces the weight of the Biomass by releasing volatile compounds as syngas transforming it into Biochar. Syngas produced is combusted to recycle energy to the LDS or exhausted to atmosphere with air as a harmless gas mixture. Biomass is moved through pyrolizer 164 using the motorised twin feed screws exiting into an Air-tight Transfer Valve (177). The ATV transfers the biochar into the Biochar Collecting Chamber (BCC) 193. Exhaust gas from Syngas combustions is filtered through the collected biochar stored in the BCC before being vented to atmosphere as harmless emissions.

The present system and apparatus are configured for different implementations and operations dependent upon orientation. For example, in a horizontal orientation/configuration the apparatus is positioned beneath the vehicle floor and exposed to atmospheric elements for venting and cooling purposes. Additionally, the present apparatus is capable of vertical orientation/configuration for installation on-board a vehicle above the vehicle floor.

The present apparatus comprises multiple different treatment processes controlled and operated according to a predefined sequence of treatment cycles including separation; filtration, distillation, drying, pyrolysis, energy recovery; storage; distribution and discharge. Separation

Wastewater discharged from the toilet, each time it is flushed, enters the system via tank 32. From here it is routed by gravity into the separator 31 which is in the open position. Biomass (faeces, paper and bound Liquid) is retained in the Wastewater Collecting Tank (WCT) 32 whilst liquid is routed through the separator mesh straining screen as it flows (containing suspended solids less than 1mm in size) into the Liquid Treatment Control Tank (LTCT) 78 through the Solids Settlement Tank (SST) 73. Liquid is retained in the SST to allow denser solids to settle out before liquid overflows into the LTCT. Sludge Collecting Tank (SCT) 74 is located below the SST and connected to it by a Sludge Isolating Valve (SIV) 80. The SST is connected to the LTCT by an overflow pipe and a Liquid Transfer Valve (LTV) 75. When a train is ‘Out of Service’ an automated routine is initiated to transfer sludge to the Dryer and settled Liquid to the LTCT. Wastewater Treatment (WWT) is initiated when the Liquid in the LTCT exceeds a pre-set level. When WWT is initiated the toilet flush is disabled and the WCT inlet valve 59 is closed. The pressure in the WCT is raised above atmospheric by the application of (compressed) air (VBV) 207. The Separator mesh straining screen is oscillated a pre-set number of times by linear actuators to transfer biomass to the dryer inlet. Knife blades (not shown) are mounted and used within the Separator to cut up large objects that have been collected in the WCT. On completion of biomass transfer the WCT is vented to atmosphere (depressurised VBV), its inlet valve 59 is opened, separator 31 is opened and the toilet flush is enabled. Sink Wastewater (SWW) does not enter the WCT. Sink wastewater enters the present system via the dedicated Sink Wastewater Tank (SWWT) 98. Sink Wastewater treatment is initiated when the Liquid in the SWWT exceeds a pre-set level.

Filtration

Following separation, toilet wastewater liquid (containing suspended solids) is treated by a single pump (FCP) two stage (Fl + F2) crossflow Membrane Filtration System (MFS). The MFS pumps (FCP) Liquid from the LTCT through the first stage Micro filter 82 and returns it as retentate to the LTCT. Filtration permeate is routed via Buffer Tank (FBT) 107 through the second stage Nano filter 104. Second stage filtration retentate (first stage permeate) is routed in the reverse flow direction from (FBT) Tank 107 using air pressurisation back to the LTCT through the first stage Micro filter 82 to dislodge retained biomass residue. This prevents progressive degradation of the Micro filter’s performance. Nano filter residue cannot be satisfactorily removed by reverse flow techniques and must be removed for cleaning during planned maintenance. Permeate from second stage Nano filter 104 is routed to Distillation Vapourisation Tank (DVT) 195 where it is stored ready for distillation. Sink wastewater is not treated by the MFS. Sink wastewater is routed to a Sink Wastewater storage Tank (SWWT) 98. When the Liquid in the SWWT exceeds a preset level it is routed to a dedicated DVT 196 through a single stage (SWWF) Filtration System (SFS) where it is stored ready for distillation.

Distillation

The MFS outputs Liquid (no suspended solids) to the Liquids Distillation System (LDS). Whilst a train is in service the present system is in its ‘ready state’ and maintains its LDS at a pre-set temperature. The LDS consists of a segregated Dual Vapourisation Tank (DVT) 195/196, a pumped (CRP) Cooling Water Recirculation Tank (CRT) 122 and two distilled water storage tanks - Flush water storage (FDWT) 130 and Sink water storage (SDWT) 140. The Liquids in tanks 195 and 196 are not allowed to mix but are simultaneously heated by combusted syngas (CCS & SCC) (energy recovery). To provide independence of operation and operation without syngas combustion, each tank is heated by a thermostatically controlled electric immersion heater (Flush - FIH & Sink - SIH). When heating the VDT using recovered energy from syngas combustion (CCS & SCC) thermostatic controls (FIH & SIH) disable energy input from immersion heaters (FIH & SIH) when vaporizing whilst Liquid temperature exceeds a pre-set value. Liquids are distilled by heat vapourisation in the VDT. Vapour produced is routed to the FDWT and SDWT through a common vapour/Liquid heat exchanger (Condenser) 110. Cooling water is pumped (CRP) from the CRT 122 through the cooling side of heat exchanger 110, condensing the vapour in the hot side producing pure distilled water. Pure water is separately routed to tank 130 for Flush water storage (FDWT) and tank 140 for Sink water storage (SDWT). A distillation treatment cycle is initiated when the water volume in either the FSWT or the SDWT falls below a pre-set level. Drying

Following separation, toilet wastewater biomass (containing faeces, paper and bound Liquid) is treated by a heat energy drying system (dryer 152). Whilst a train is in Service, the system is enabled and maintains its drying system at a pre-set temperature. On initiation of WWT the dryer 152 is closed to atmosphere (SEV) and air is evacuated (VEV) to generate a negative internal pressure. When the dryer internal pressure is less than a preset value biomass, accumulated in the separator 31 is deposited by gravity assisted by positive pressure in the Separator (VBV), oscillation of the separator 31 and negative pressure in the dryer 152 into the Dryer inlet port. The inlet to dryer 152 is positioned below its outlet. The Dryer temperature is raised to a pre-set value by the Dryer Heating Controller (DHC) and the dryer is started. The Dryer Vapour Vent valve (DVV) 154 is opened and the Vapour Extraction Venturi valve (VEV) is started to exhaust vapour evolved from drying to the atmosphere. When dryer 152 has reached its pre-set temperature the Dryer Motor Controller (DMC) is started to feed biomass at a pre-set rate for a pre-set time through dryer 152 to reduce the mass of bound liquid in the biomass and charge the outlet Air-tight Transfer Valve (ATV1). After a pre-set time the biomass feed is stopped (DMC). After a further pre-set time the dryer temperature is reset to a pre-set valve by the (DHC), vapour evacuation is stopped (VEV) and the dryer vent valve is closed (DVV).

Pyrolysis

Dried biomass is treated by a heat energy pyrolysis system (pyrolizer 164). Whilst a train is in service, the system is in its ‘ready state’ and maintains its pyrolyzing system at a pre-set temperature. On initiation of WWT pyrolizer 164 is closed to atmospheric pressure and air is evacuated (BVX) to the atmosphere to generate a negative pressure. When the pyrolizer’ s internal pressure is less than a pre-set value its temperature is raised to a pre-set value by the Pyrolizer Heating Controller (PHC) and the pyrolizer is started, (energy recovery). When the pyrolizer 164 has reached its pre-set temperature profile biomass is transferred into it by ATV1. The Pyrolizer Motor Controller (PMC) is started to feed biomass at a pre-set feed rate for a pre-set time through pyrolizer 164 to reduce the biomass to biochar and charge the outlet Air-tight Transfer Valve (ATV2) 177. After a preset time the biomass feed controller is stopped. After a further pre-set time the pyrolizer temperature profile is reset to a pre-set value (PHC), biochar is transferred to the Biochar Collecting Chamber (BCC) 193 by ATV2 and air evacuation (BVX) is stopped.

Energy Recovery

Syngas evolved from pyrolysis is mixed with compressed air 207 and combusted using a Combustion Control System (CCS) in a Syngas Combustion Chamber (BCC) positioned below the distillation vapourisation tank (DVT) 195/196. Syngas is evacuated from the pyrolizer 164 through a Syngas Manifold Pipe (BMP) 167 using the Syngas/air Mixing Venturi valve (BVX) 181 and routed to the combustion control system (CCS) by flow control valves (BFC) 183. Exhaust gas from the combustion chamber (BCC) is routed to the Biochar collecting chamber (BCC) 193 under mixing pressure (ABP). Biochar in the collecting chamber is supported above a void on an air/gas permeable flat membrane filter. The atmosphere in the void is evacuated to the atmosphere generating a negative pressure to draw gas through the collected biochar and filter membrane to exhaust to atmosphere using the Exhaust gas Evacuation Venturi valve (XEV) 190. Syngas can be exhausted without combustion by the flow controls valves (BFC) 183 venting to the atmosphere at exit from the air/Syngas mixing valve (BVX) 181.

Storage

Toilet waste liquid is stored, transferred and treated using the following tanks in sequence: waste collecting tank 32 collects all toilet wastewater, routes liquid to the separator 31 and stores biomass; Solids Settlement Tank 73 receives all liquid output from the separator 31; sludge tank 74 collects settled solids (as sludge) from the tank 73; liquid treatment control tank 78 initiates wastewater treatment; filter buffer tank 107 receives permeate from the stage 1 filter and feeds it to the stage 2 filter; dual vapourisation tank 195 receives permeate from the second stage filter and feeds the flush water to the flush water storage tank 130; flush distilled water tank 130 stores flush water and feeds the toilet flush system; cooling water recirculation tank 122 feeds the heat exchanger (condenser) with cooling water; sink wastewater storage 98 stores sink wastewater and feeds the single stage sink filter; dual vapourisation tank 196 receives filtered water from the sink wastewater tank and feeds the sink water storage tank 140; and sink distilled water tank 140 stores sink water and feeds the sink taps. Distribution

Toilet wastewater enters the WCT under gravity flow or a pressurised flow from a compact vacuum toilet system. Toilet wastewater liquid flows through the separator 31 under gravity and then under pressure when the LTCT volume reaches a pre-set amount. Separated liquid flows under gravity to the SST and then overflows into the LTCT.

Liquid in the LTCT is pumped using the air operated diaphragm pump (FCP) 85 through filter 82 as crossflow retentate back to the LTCT and as permeate outflow into the filters 82, 104 and the Buffer Tank (FBT) 107. Filtered liquid from filter 82 is forced to flow by an increased pressure (T2AP) in the FBT through filter 104 as crossflow retentate back through the filter permeate outlet in reverse direction as inflow then back to the LTCT and as permeate flow into the flush water Dual Vapourisation tank (DVT) 195. Vaporised liquid in tank 195 transfers to the Flush water storage tank (FDWT) 130 under vapour pressure through heat exchanger (CWL) 110 where it condenses to produce pure distilled water. Cooling water is pumped (CRP) from the cooling water recirculation tank (CRT) 122 through the heat exchanger (CWL) and returned to the CWL. Flush water is supplied to the toilet system on demand by an increased pressure in the FDWT. Sink wastewater flows under gravity from the sink outlet into the Sink Wastewater tank (SWWT) 98. Liquid in the SWWT is forced to flow through a single stage Sink filter (SWWF) 100 by an increased pressure (SWAP) in the SWWT into Sink water Dual Vapourisation tank (DVT) 196. Vaporised Liquid in tank 196 transfers to the Sink water storage tank (SDWT) 140 under vapour pressure through a heat exchanger where it condenses to produce pure distilled water. Sink water is supplied to the sink on demand by an increased pressure in the SDWT.

Discharge

In operation all Liquid discharged is clean and harmless and is routed to the common discharge manifold 192 for discharge on or near the centre of the vehicle.

When being maintained stored dirty liquids can be safely extracted from tanks 32, 73 and 78 using convention CET servicing equipment. Filtered clean harmless liquid/water can be extracted using tank drain valves. Biochar can be extracted using a mobile vacuum extraction unit. A further specific implementation of the wastewater treatment system (as described referring to figures 7 to 12) is detailed below referring to figures 13 to 18. The architecture and operational function of the system of the second embodiment are generally the same as the first embodiment and accordingly the components and function at the various stages of waste collection, solid-liquid separation, liquid/slurry filtration and processing, solid processing, purification, liquid reuse/recycling and solid biomass generation and collection/discharge are the same and common to the first embodiment. However, the second embodiment differs in certain respects as detailed below.

Referring to figure 13 the construction and function of the present system according to embodiment two is very similar to that of embodiment one described referring to figure 2. However, according to the further embodiment, liquid processed by the system and output as flush water 27 is first transferred to the purification unit 22 in contrast to this flush water being supplied directly by the second filter at stage 23. Additionally, tanking tank 16 is coupled to feed the purification vapourisation/condensation assembly (tank 196, figure 10) at stage 22 with the result of the purification being the output of processed and cleaned sink water 26. Additionally, tanking tank 16 may be fed from a freshwater top-up source 206. Output from the discharge manifold is then vacuum output as safe liquid/gas emissions 204. In particular, the discharge manifold 192 is supplied with a source of air 201, syngas 21 A generated from the pyrolizer and any excess pre-treated liquid waste 202. The discharge stage 200 is conducted under vacuum 203 whereby the diluted syngas is vacuum transferred to excess water for cooling 203. The diluted syngas and excess water is then discharge as safe liquid/gas emissions 204 onto the track 13. According to the second embodiment of figure 13, the sink wastewater may be discharge directly 205 onto track 13 as an optional stage relative to the processing 29 initially by passage of the waste water 18 to the sink waste filter.

Referring to figures 13 and 18, the waste treatment system according to the further embodiment is suitable for installation at a stationary location or within a mobile unit, vehicle or carriage such as a train carriage. Referring to figures 14, the solid-liquid separation utility forming part of the larger waste treatment system of figure 13 according to the further embodiment comprises those components as described referring to figure 2 including wastewater receiving tank 32 to receive and store wastewater discharged from toilet; level switch 61 to transmit a fault signal to a programable logic circuit (PLC) to hold the system when the wastewater receiving tank is full. The system further comprises pressure transmitter 48 to transmit (plus/minus) pressure to the PLC; a tank inlet shut off valve 59 to isolate wastewater receiving tank from toilet discharge; a blow-down valve 66 coupled to a (compressed) air source 207 to generate pressure in the tank 32; separator 31 to separate wastewater into liquid & wet (biomass) solids; a washdown valve 208 to washdown the wastewater receiving tank 32; an air supply filter regulator to control and monitor main air supply; and a (compressed) air source 207 to deliver (compressed) air to the separator 31.

An example operating sequence of the separator 31 may be described as: start position (open) ready to receive waste. The sequence continues with toilet used - flushed wates enters separator 31; the separator 31 does not rotate to allow time for liquid to drain to tank 32; the separator 31 does not rotate until five flushes have been logged; after fifth flush timer initiated for period required to drain the separator outflow tube 37a into liquid to tank 73; if the toilet is not flushed before the timer expires then the separator 31 rotates (oscillates) to discharge solids to dryer 152; if the toilet is flushed (6th flush) then the timer is initiated and so on until it expires without interruption and the separator 31 transfers waste to the dryer 152.

Referring to figure 15, the further embodiment comprises a solid-liquid filtration utility forming a part of the overall waste treatment system of figures 13. The filtration utility comprises solids settlement tank 73 to settle solids from separated liquid and overflow to the Liquid Treatment Control Tank (LTCT); circulation tank 78 to store settled liquids and feed the circulation pump 85; level transmitter 77 to transmit the LTCL level to the PLC and initiate wastewater treatment; sludge transfer valve 150 to transfer sludge from tank 73 to the dryer inlet; pump 85 configured to provide fluid circulation and to circulate settled liquid through first and stage filters 82; a flow transmitter 213 to transmit/pump Pl (85) flow to the PLC to control the air pressure at pump 85; a safety valve 71 to prevent over pressurisation of filter 104; a sediment filter 211 to remove sediment prior to passage to the micro filter 104; a reverse flow prevention valve 250 to prevent reverse flow of filter backwash liquid; stage 1 filter 82 (micro) to filter settled liquid to remove suspended solids; pressure transmitter 81 to transmit filter 82 back pressure to the PLC (to monitor filter 82 crossflow press); filter back pressure valve 70 to balance permeate/retentate flows during stage 1 filtration; pressure/vacuum relief valve 76 to allow air in/out of tanks 73 and 78; sediment pre-filter backwash valves 212 to backwash sediment pre-filter 211 with filtered liquid from tank 107; settled liquid transfer valve 75 to transfer liquid from the Solids Settlement Tank (SST) (tank 73) to the LTCT (tank 78); flow transmitter 91 to transmit filter 82 permeate flow rate to the PLC (to control the pumps); tank inlet valve 69 to isolate tank 107 to route filter retentate of filter 104 through filter 82 and back to tank 73; second pump 93 to circulate first-stage filtered liquid through second stage filter 104 (nano); buffer tank 107 being fed by filters 82 and 104; a pump shut-off valve 214; pressure/vacuum relief valve 95 to allow air in/out of tank 107; level transmitter 106 to transmit the FBT level to the PLC (control filtration cycle); stage 2 filter 104 configured to filter liquid and to remove bacteria and viruses; pressure transmitter 103 to transmit back pressure of filter 104 to the PLC (filter 104 crossflow pressure); back pressure valve 102 to balance permeate/retentate flow at stage 2 filtration (filter 104); reverse flow prevention valve 90 to prevent reverse flow of filter backwash liquid; back pressure bypass valve 215 to enable backwash liquid to bypass the back-pressure valve 70 of filter 82; flow transmitter 108 to transmit permeate flow rate of filter 104 to the PLC; flow transmitter 210 to transmit delivery flow rate of pump 93 to the PLC; and a reverse flow conduit 216 from filter 100 (figure 16a) to an inlet of tank 73.

Referring to figures 16a and 16b, a purification utility/assembly forming part of the overall waste treatment system of figures 13 is described according to the further embodiment. The purification utility is configured to process separate input flows of waste liquid from a first source such as a toilet and second source such as a sink. The purification utility according to the further embodiment comprises flush water heating tank 195 to store permeate from filter 104 for purification; flush water immersion heater 228 to heat the permeate to a sterilisation temperature of around 80°C; temperature transmitter 117 to control the flush water pasteurisation temperature (at tank 195); level switch 114 to monitor the flush water level at tank 195 and output to the PLC; flush water cooling tank 130 to store pasteurised permeate from filter 104 for cooling; a flush and sink water feed pump 229 to supply flush and sink water; level transmitter 125 to transmit a cooled flush water level to the PLC (tank 195); a flush water off-load pressure relief valve 231 to offload flush water when sink water demanded or flush is stopped; a non-return valve 232 between accumulator 233 and pressure relief valve 231; a flush water accumulator 233 to supply a pressure boost; an active carbon filter (GAC) 234 to deodorise and clarify flush water; a flush water drain valve 230 to release accumulator charge and allow filter change; an active carbon filter (GAC) 219 to deodorise vapour extracted from the dryer 152; a receiving tank (tank 32) non-return valve 220; a sink water freshwater top-up tank 221 fed by a detachable external supply source 222; a vapour vacuum pump 251 to extract vapour from the dryer/evacuate the dryer atmosphere fed by a (compressed) air source 207; sink water heating tank 196 to store filtered sink wastewater for purification; sink water immersion heater 227 to heat sink wastewater at a pasteurisation temperature of around 80°C; a temperature transmitter 111 to control the sink water pasteurisation temperature (tank 196); level switch 113 to monitor the water level in tank 196 and output to the PLC; sink water cooling tank 140 to store filtered sink wastewater for cooling; a level transmitter 148 to transmit a water level of the cooled flush water (at tank 140) to the PLC; a sink water off-load pressure relief valve 236 to off-load sink water when flush water is demanded and taps are closed; a non-return valve 237 to prevent reverse flow of the sink water supply pressure; a sink water pressure accumulator 238 to supply a pressure boost to sink waste water; active carbon filter 239 to deodorise and clarify sink water; a sink water drain valve 235 to release accumulator charge and to allow filter change; sink wastewater tank 98 to store sink wastewater for filtration; a non-return valve 88 to prevent sink wastewater reverse flow; level transmitter 96 to initiate transfer of sink wastewater to the purification utility; pressure transmitter 97 to prevent over pressurisation of sink wastewater tank 98; a non-return valve 217 to prevent backwash flow from entering sink wastewater tank 98; sediment filter 100 to remove sediment; a backwash pressure relief valve 218 to allow sink filter backwash flow to tank 73; filtered flow reverse non-return valve 240 to prevent filtered sink wastewater bypassing tank 196; a sink wastewater shutoff valve 241 to allow filtered sink wastewater flow to purification tank 196 and prevent backwash flow to tank 196; a tank (196) filtered sink waste water non-return valve 223; a tank (196) vapour non-return valve 224; a tank (196) top-up non-return valve 225; a tank (195) filtered toilet waste water non-return valve 226 to prevent heated flush water reverse flow to nano filter 104; optionally a non-return valve (not shown) coupling vacuum pump 251 to tank 98 to prevent sink wastewater flow into a dryer vapour discharge pipe; pressure transmitter 145 to transmit flush water supply pressure to the PLC; temperature transmitter 144 to transmit flush water supply temperature to the PLC (common sensor); a pressure transmitter 147 to transmit sink water supply pressure to the PLC; and a temperature transmitter 146 to transmit sink water supply temperature to PLC (common sensor).

Referring to figures 17a and 17b, the configuration and function of the dryer and pyrolizer to receive and process predominantly solid waste according to the second embodiment are common with the first embodiment save for following changes. Referring to figure 17a, at the output end of dryer 152, a dryer vapour pressure transmitter 242 is provided proximate to the temperature transmitter 151 (also attached at the hotter discharge end). As described elsewhere, 207 refers to the supply of (compressed) air for example to the air-tight transfer valve 157 via a solenoid control valve to move solids from the dryer to the pyrolizer. Referring to figure 17b, a corresponding air-tight transfer valve 177 is actuated via the electronically controlled solenoid and (compressed) air source 207 to move biochar from the pyrolizer to the char collecting chamber.

Referring to figure 17b, syngas outflow 178 from pyrolizer 164 is transferred to the syngas mixer mechanism 181 (figure 18). The mixer mechanism 181 acts as a gas-air cooler which is collocated with the excess liquid discharge manifold 192, and in particular is located within the discharge manifold 192 that provides the function as a gas-liquid cooler. Accordingly, overflow toilet and sink waste (water) are transferred to the discharge manifold 192 (after purification) that contains the chamber (air-syngas mixer) 181 that receives the syngas output from pyrolizer 164. As described manifold 192 is configured to receive overflow discharged liquid from the purification utility and in particular overflow where capacity within tank 140 and/or 130 are at a maximum. The syngas output from the pyrolizer is then cooled within chamber 181 firstly by contact with the ‘cooler’ air from source 207 (also introduced into chamber 181) and secondly via contact with the ‘cooler’ liquid within manifold 192. The causes the moisture and the condensable components of the syngas to condense and hence the syngas to be solvated by the condensed liquid/water. The syngas condensate may then be discharged to the track 13 as excess liquid via one or more discharge oil removal filters 248 (a chemical and/or biological filter) that function to remove bacteria, pathogens, toxins etc and/or odour (originally present within the human waste) from the syngas condensate. Non-return valves 182, 243 and 183 provide the nonreturn flow syngas and air into the gas-air cooler and at manifold 192. Discharge manifold (incorporating the syngas cooler 181) provided at the discharge end of the system is also provided with a discharge manifold temperature sensor 244; a discharge manifold pressure sensor 245; an air/syngas mixing temperature sensor 246; an air/ syngas mixing pressure sensor 247. As illustrated in figure 18, manifold 192 is provided with a conduit for the outflow of gas and liquid from the gas-air cooler 181 to a liquid discharge manifold 192 via an exhaust gas venturi valve 190 provided in-series with a syngas flow control valve 183 at the inlet end of venturi valve 190 in addition to a second non-return valve 183 provided at the outflow end of venturi valve 190. Control valve 183 is configured to prevent overheating of the venturi valve 190.

As described and referring to figures 17a and 17b, the solid treatment utility of the present waste treatment system of figure 13 according to the further embodiment comprises the dryer 152 to reduce bound water in solids sludge; heating controller 158 to regulate current to electrical heating tape at dryer 152; motor and controller 165 to regulate and control the wet solids/sludge dryer feed rate; temperature transmitter 155 to transmit dryer inlet temperature to the PLC (to control the dryer ready temp); temperature transmitter 151 to transmit dryer outlet temperature to the PLC (to control the dryer run temp); pressure transmitter 242 to transmit dryer pressure to the PLC; pyrolizer 164 to reduce the weight of solid waste; heating controller 159 to regulate current to electrical heating tape at the pyrolizer 164; motor and controller 165 to regulate and control the solids feed rate to pyrolizer 164; temperature transmitter 169 to transmit a pyrolizer inlet temperature to the PLC (to control a pyrolizer ready temp); temperature transmitter 151 to transmit pyrolizer outlet temperature to PLC (control pyrolizer run temp prof); pressure transmitter 168 to transmit pyrolizer pressure to the PLC; air-tight transfer valve 157 to move solids from dryer to pyrolizer (with no airflow); air-tight transfer valve 177 to move biochar from pyrolizer to the char collecting chamber 193 to collect/discharge char and filter combustion exhaust gases from pyrolizer 164; temperature transmitter 184 to transmit BCC temperature to the PLC; and pressure transmitter 185 to transmit BCC pressure to PLC (common sensor).

The operational function of the liquid and biomass solid waste treatment system of the second embodiment corresponds to the that of the first embodiment with the following variations due to the constructional changes as described.

On completion of biomass transfer to the dryer, the separator is left in the opened position and liquid flows by gravity to tank 73 such that sink wastewater enters the present treatment system via the dedicated sink wastewater tank 98 (referring to figure 16a). As part of the filtration of sediment by the micro membrane and nano membrane filters 82, 104, unfiltered retentate (crossflow) flows back to tank 73; the filtered output, permeate is routed to a buffer tank 107; and the pumps pump liquid from tank 107 through membrane filters 82, 104 in which nano filtration retentate (crossflow - Micro filter permeate) routed from tank 107 through the micro filter 82 permeate flow channel in the reverse flow direction to reduce membrane fouling. This backwashing helps to prevents progressive degradation of the micro filter performance. The Nano membrane filter is mounted at the system to be configured for removal for cleaning during planned maintenance.

To reduce energy draw during dryer and pyrolizer heating, as soon as service is started (e.g., a train enters its "In Service" state) heat is applied to the dryer and pyrolizer to increase and maintain their respective operating temperatures. When the train enters an "Out of Service" state heat energy is terminated to both the Dryer and Pyrolizer.

During solid-liquid separation processing, after a pre-set number of toilet flushes (e.g., four) separator 31 is oscillated to move biomass into the dryer inlet to help prevent fouling of the separator mesh. This action does not start the drying treatment but may require the dryer feed screw to make periodical forward and reverse rotations to prevent pre drying clogging of the dryer inlet. Drying treatment is initiated when the level in tank 78 exceeds a pre-set level. After separation, the Dryer Motor Controller (DMC) is started to feed biomass at a pre-set rate for a pre-set number of revolutions through the dryer 152. This reduces the mass of bound liquid in the biomass (driven off as vapour) and charges the outlet air-tight transfer valve 157 with dried biomass. After a pre-set number of rotations, the dryer biomass feed screw is stopped.

To optimise pyrolysis whilst a train is "In Service" the present system is in its ready state and maintains its pyrolyzing utility at operating temperature. After a pre-set number of drying cycles, the pyrolizer vacuum pump is started to create a negative pressure inside the pyrolizer. During the transfer of dried biomass to the pyrolizer inlet it may be necessary/desirable to rotate the dryer feed screw to ensure maximum biomass transfer. After biomass transfer, the Pyrolizer Motor Controller (PMC) is started to feed dried biomass at a pre-set feed rate for a pre-set number of revolutions through the pyrolizer. This reduces the dried biomass to biochar (volatile compounds are driven off as syngas) and charges the outlet air-tight transfer valve 177 with biochar. During the transfer of biochar to the char box 186 it may be necessary/desirable to rotate the pyrolizer feed screw to ensure maximum biochar transfer.

As part of the discharge processing of excess clean water and syngas, syngas gas is mixed with air and purified and/or excess liquid in discharge manifold 192 before being discharged. Also, syngas, evolved when biomass is reduced by the pyrolysis to biochar, is discharged to atmosphere via the air and liquid-gas cooling discharge assembly (181, 192) and the coalescing oil removal filter 248. In particular, the discharge manifold 192 is configured to ‘clean’ the syngas by dilution/mixing it with compressed air (source 207) and the purified liquid (from the upstream purification units). The processing of the syngas by the manifold 192 is effective to condense bio-oil (generated from the syngas) within the manifold 192. This bio-oil is then removed/absorbed by filter2 48 as a final stage prior to discharge as detailed in figure 18.

A further embodiment of the present concept involves solid-liquid matter phase separation via distillation. The third embodiment obviates a requirement to mechanical separate the liquid phase from the solid phase and instead achieves this via liquid distillation in which the liquid distillate (and product gases) are removed from the solid matter via heating within a heating chamber of a heating unit using the components and function of the apparatus of the second embodiment described referring to figures 13 to 18. Referring to figure 19, a shut off valve 260 is provided at the outlet port of the predominantly liquid outlet of solid-liquid separator 31. Valve 260 is effective to close the liquid outlet of separator 31, with the separator configured as an airtight waste transfer valve configured to transfer solid and liquid waste from waste receiving tank 32 to the heating unit (dryer 152) and/or pyrolizer 164 as detailed referring to figures 17a and 17b in respect of the second embodiment. The features and function of embodiments one and/or two are incorporated within embodiment three in addition to the components, (features and function of figures 2 to 7 and 7 to 18, respectively).

In particular, and according to the third embodiment, the mixed solid and liquid waste received at the heating unit (dryer 152 and/or pyrolizer 164) may then be heated within the respective internal chambers of a heating unit (unit 152 and/or unit 164). Liquid-phase waste would then be collected as a distillate in addition to gas-phase products of the heating/pyrolysis process. The output liquid-phase waste may then be processed by the liquid waste processing arrangement and/or purification assembly, as described herein, referring to the first and/or second embodiments of figures 2 to 18 so as to filter and purify the liquid condensate to remove any bacteria, pathogens, toxins etc. The liquid collected from the heating unit (152 and/or 164) is then processed and ready for return delivery to a tap 56/sink 14 and/or flush mechanism 57 (referring to figures 7, 14 and 19).

The syngas generated from the heating unit (152, 164), according to the third embodiment is then delivered to the syngas processing unit described referring to figure 18. In particular, and as described in the second embodiment, the syngas product is mixed with air within chamber 181. The syngas components are condensed with the water vapour (from steam contained within the syngas) and air from source 207 input into chamber 181. This condensation is achieved, as indicated, by mixing with the "cooler" air 207 and by contact with the "cooler ’ liquid within manifold 192 that encapsulates chamber 181. The syngas condensate may then be processed by those components as described referring to figure 18 prior to filtration by filter 248 to remove syngas oils (i.e. bacteria, pathogens, toxins and other biological contaminants) prior to discharge to the track 13.

As described, the first and second embodiments referring to figures 7 and 14 may also comprise a shut off valve 260 at the predominantly liquid output port of separator 31 such that the first and second embodiments may also operate to provide solid and liquid phase waste separation via distillation/heating within one or both of the heating units (152 and/or 164). The third embodiment and any modified first and second embodiment, may then optionally comprise the subsequent liquid waste processing arrangement (components and function) as well as the purification assembly (components and function).