Abstract: The present invention provides a method and system (1) for producing oxygen. Oxygen-carrier particles are transferred between a reduction process (10) and an oxidation process (15) connected to form a chemical looping process. The reduction process produces oxygen-depleted carrier particles and an exhaust gas mixture. Oxygen is separated from the exhaust gas mixture, preferably by a condenser (5). The oxygen-depleted carrier particles are returned to the oxidation process for regenerating the oxygen-depleted carrier particles with oxygen. The reduction process is performed during a first time period and the oxidation process is performed in a second time period.

Abstract: The present invention provides a method (1) and system for the removal of tar from a synthesis gas (10) using a chemical loop (23). A first reactor (20, 55) is fed with mineral particles and the synthesis gas. The mineral particles catalyse the tar in the synthesis gas to produce a mixture comprising hydrogen and a mineral carbonate. A second reactor (15, 70) is fed with oxygen and the mineral carbonate. The oxygen reacts with the mineral carbonate to produce a flue gas (25) comprising carbon dioxide and mineral particles, which are then separated and the mineral particles are recycled to the first reactor.

Abstract: A method and apparatus for removing methane from ventilation air in a mining situation is provided by a carbonation reactor CAR which reacts a ventilation air methane stream VAR with a carbon dioxide scavenger to form a mineral carbonate which is passed to a calcination reactor CAL in which a regeneration reaction decomposes the mineral carbonate back to a mineral or mineral oxide. Additional heat may be added to the CAL by steam, solar energy or by burning drainage gas, natural gas, or coal. Steam or supercritical fluid given off by the CAR can be utilized for heating, cooling, or energy generation. The carbon dioxide scavenger can be any metal, metal oxide, mineral or mineral waste having a carbonation tendency, used in the process referred to as “Mineral Carbonate Looping Reactor” (MCLR), or can be stone dust from the mining site used in the process referred to as “Stone Dust Looping Reactor” (SDLR).

Abstract: An integrated chemical looping air separation unit (5) in a large-scale oxy-fuel power generating plant takes a portion of recycled flue gas (6) via a recycling conduit (7) through a heat exchanger (8) to a reduction reactor (9). The reduction reactor (9) exchanges oxidized metal oxide with an oxidation reactor (11) via transfer means (10) which return reduced metal oxide from the reduction reactor (9) to the oxidation reactor (11). This enables the reduction reactor (9) to feed a mixture of oxygen and recycled flue gas into the boiler (13) of the power generating plant in a more energy efficient manner than conventional oxy-fuel power plants using air separation units.

Abstract: Methane is removed from ventilation air by cycling metal or metal oxide particles in a chemical looping process in one or more reactors where the metal particles are alternately reduced and oxidized, and passing ventilation air through one or more of reactors to convert the air plus methane into reduced air, water and carbon dioxide. In one variation, a hydrogen generator and a regenerator are used to alternatively reduce and oxidize the particles such that ventilation air methane introduced into a combustor provided with hydrogen from the hydrogen generator can be processed in the regenerator to produce air, water and carbon dioxide. Other variations involve using three reactors in the chemical looping process, or an array of parallel inclined plates forming lamellas between upper and lower reactors to keep lighter particles in the upper oxidizer reactor and heavier particles in the lower reducer reactor.

Abstract: In a coal fired power plant (17) incorporating a feed-water heater (10), energy is provided to the feed-water heater by pumping geothermal hot water through supply and return pipes (15, 16) from a geothermal reservoir (14) located beneath an adjacent coal seam (19). The coal seam acts as an insulating layer, increasing the temperature of the geothermal reservoir (14). Solar heat collectors (21) and (25) can also be provided to boost the temperature of the geothermal hot water and/or the feed water.

Abstract: Methane is removed from ventilation air by cycling metal or metal oxide particles in a chemical looping process in one or more reactors where the metal particles are alternately reduced and oxidised, and passing ventilation air through one or more of said reactors to convert the air plus methane into reduced air plus water plus carbon dioxide. In one variation, ventilation air methane (VAM) is removed from ventilation air in coal mines using a chemical looping process to move metal or metal oxide particles between reactors such as a hydrogen generator (5) and a regenerator (7) to alternatively reduce and oxidise the particles such that VAM introduced into a combustor (6) provided with hydrogen from the hydrogen generator (5) can be processed in the regenerator (7) to produce air plus water plus carbon dioxide.

Abstract: An integrated chemical looping air separation unit (5) in a large-scale oxy- fuel power generating plant takes a portion of recycled flue gas (6) via a recycling conduit (7) through a heat exchanger (8) to a reduction reactor (9). The reduction reactor (9) exchanges oxidised metal oxide with an oxidation reactor (11) via transfer means (10) which return reduced metal oxide from the reduction reactor (9) to the oxidation reactor (11). This enables the reduction reactor (9) to feed a mixture of oxygen and recycled flue gas into the boiler (13) of the power generating plant in a more energy efficient manner than conventional oxy-fuel power plants using air separation units.

Abstract: In a coal fired power plant (17) incorporating a feed-water heater (10), energy is provided to the feed-water heater by pumping geothermal hot water through supply and return pipes (15, 16) from a geothermal reservoir (14) located beneath an adjacent coal seam (19). The coal seam acts as an insulating layer, increasing the temperature of the geothermal reservoir (14). Solar heat collectors (21) and (25) can also be provided to boost the temperature of the geothermal hot water and/or the feed water.

Abstract: A method of generating power from a heat source, said method including: compressing (10) a working fluid to increase its temperature; exchanging (11) heat between said working fluid and said heat source to superheat said working fluid; expanding (12) said superheated working fluid to drive a turbine, thereby reducing its temperature; condensing (13) said working fluid to further reduce its temperature: and returning said working fluid to said compressing step (10), the method further including the step (14) of regenerating the heat of said working fluid wherein working fluid passing between said compressing step (10) and said heat exchanging step (11) exchanges heat with working fluid passing between said expanding step (12) and said condensing step (13); wherein said steps are performed in a thermodynamic cycle (S1-S1?-S2-S3-S3?-S4) within a supercritical region (SC) above the saturation dome (A) of said working fluid, and wherein said heat regenerating step (14) is performed under isenthalpic conditions to

Abstract: A method of generating power from a heat source, said method including: compressing (10) a working fluid to increase its temperature; exchanging (11) heat between said working fluid and said heat source to superheat said working fluid; expanding (12) said superheated working fluid to drive a turbine, thereby reducing its temperature; condensing (13) said working fluid to further reduce its temperature: and returning said working fluid to said compressing step (10), the method further including the step (14) of regenerating the heat of said working fluid wherein working fluid passing between said compressing step (10) and said heat exchanging step (11) exchanges heat with working fluid passing between said expanding step (12) and said condensing step (13); wherein said steps are performed in a thermodynamic cycle (S1-S1?-S2-S3-S3?-S4) within a supercritical region (SC) above the saturation dome (A) of said working fluid, and wherein said heat regenerating step (14) is performed under isenthalpic conditions to

Abstract: An integrated chemical looping air separation unit (5) in a large-scale oxy-fuel power generating plant takes a portion of recycled flue gas (6) via a recycling conduit (7) through a heat exchanger (8) to a reduction reactor (9). The reduction reactor (9) exchanges oxidized metal oxide with an oxidation reactor (11) via transfer means (10) which return reduced metal oxide from the reduction reactor (9) to the oxidation reactor (11). This enables the reduction reactor (9) to feed a mixture of oxygen and recycled flue gas into the boiler (13) of the power generating plant in a more energy efficient manner than conventional oxy-fuel power plants using air separation units.