244 results about "Chemical looping combustion" patented technology

A system and method for biomass pyrolysis utilizing chemical looping combustion of a produced char to capture carbon dioxide is disclosed. The system includes a biomass pyrolysis reactor, a char combustor, and oxidation reactor and a separator for separating carbon dioxide from flue gas produced by the char combustion. The pyrolysis reactor pyrolyzes biomass in the presence of reduced metal oxide sorbents producing char and pyrolysis oil vapor. The char is separated and combusted in the char combustor, in the presence of oxidized metal oxide sorbents, into a gaseous stream of carbon dioxide and water vapor. The carbon dioxide and water are separated so that a stream of carbon dioxide may be captured. The oxidation reactor oxidizes, in the presence of air, a portion of reduced metal oxide sorbents into oxidized metal oxide sorbents that are looped back to the char combustor to provide oxygen for combustion. A second portion of the reduced metal oxide sorbents is recycled from the char combustor to the pyrolysis reactor to provide heat to drive the pyrolysis. Pyrolysis oil upgrading catalyst particles may be used in addition to the metal oxide sorbents as heat energy carrier particles to improve the quality of the pyrolysis oil vapors produced in the pyrolysis reactor. Also, the metal oxide sorbents may have metals incorporated therein which serve to upgrade the pyrolysis vapors produced during pyrolysis. Non-limiting examples of such metals include Ni, Mo, Co, Cr, W, Rh, Ir, Re, and Ru.

Process and apparatus are provided for a high energy efficiency chemical combustion process. The process provides two reaction steps, both of which are exothermic. First, a reduced oxygen carrier is contacted with oxygen in a reactor to form an oxidized oxygen carrier, such as metal oxide or metal suboxide, and then the oxidized oxygen carrier is fed to a second reactor and combusted with a fuel. The reaction produces the reduced oxygen carrier and carbon dioxide. The reduced oxygen carrier from the second reactor is recycled back to said first reactor. Carbon monoxide can also be produced during the process depending on stoichiometric amounts of the reactants. Though the process can be performed in various types of reactor systems, one preferred embodiment is the flash furnace with the production of fly ash during combustion. The process is highly efficient and produces a large amount of usable work.

The object of the invention is a combustion method for a solid feed using a chemical loop wherein an oxygen-carrying material circulates, said method comprising at least:

• contacting the solid feed particles in the presence of metallic oxide particles in a first reaction zone (R1) operating in dense fluidized bed mode,
• carrying out combustion of the gaseous effluents from first reaction zone (R1) in the presence of metallic oxide particles in a second reaction zone (R2),
• separating in a separation zone (S3) the unburnt particles and the metallic oxide particles within a mixture coming from second reaction zone (R2),
• re-oxidizing the metallic oxide particles in an oxidation zone (R4) prior to sending them back to first zone (R1).

The invention discloses a CO2 gas coke chemical-looping combustion power generating system and method. The system comprises a coal step gasification subsystem, a fire coal heating subsystem, a chemical-looping combustion subsystem and a power generating subsystem. According to the system and method, coal to be gasified is partially gasified through the carbonization process, coke oven gas and coarse coke are generated, then the coarse coke reacts with CO2 to generate CO, and therefore step gasification of hydrogen and carbon components of the coal is realized, moreover, an expensive air separating unit is omitted, and the system energy consumption is lowered; through chemical-looping combustion of the CO, losses in the combustion process is reduced, and the efficiency of the system is improved; through afterburning of the coke oven gas, energy waste of the coke oven gas is avoided, the temperature of a fuel gas turbine inlet is lowered, and the problem that in a chemical-looping combustion power system, due to circulation material limitation, the primary temperature of a fuel gas turbine inlet is low is solved. Due to the fact that CO2 generated in a chemical-looping combustion reduction reactor is not diluted by N2, CO2 zero-energy-consumption separation can be realized by removing steam through simple condensing.

The invention relates to the technical fields of the solar thermal power generation and energy, in particular to a solar energy and methanol fuel chemical-looping combustion power generation system and method used for controlling CO2 emission. The intermediate-low temperature solar thermochemical process and the chemical-looping combustion power cycle are coupled organically to form the system ofthe invention. The system comprises a solar heat collecting-reduction reactor, a solar heat collecting-decomposition reactor, an oxidation reactor, an afterburning combustion chamber, a gas turbine, a steam turbine, an exhaust-heat boiler, a heat exchanger and the like. By using the device of the invention, the graded use of energy resources with different qualities can be realized; the zero-energy separation of CO2 can be realized through simple condensation; the combustion method can reduce the fuel grade to FeO grade, thus reducing the fuel loss in the combustion process and increasing theefficiency of the system; the solar thermochemical reaction is adopted to improve the grade of intermediate-low temperature solar energy; and afterburning is adopted so as to solve the problem that the gas turbine inlet has low initial temperature caused by the limit of the cycle material in the chemical-looping combustion power system.

The invention relates to a device and to an improved method for chemical looping combustion of at least one liquid hydrocarbon feed, comprising: mixing the liquid feed with an atomization gas so as to feed it into a metal oxide transport zone (2), upstream from combustion zone (3), through atomization means (6) allowing to form finely dispersed liquid droplets in the atomization gas; spraying the liquid feed in form of droplets into contact with at least part of the metal oxides in transport zone (2), the operating conditions in transport zone (2) being so selected that the superficial gas velocity after spraying the liquid feed is higher than the transport velocity of the metal oxide particles; sending all of the effluents from transport zone (2) to a combustion zone (3) allowing reduction of the metal oxides, said combustion zone (3) comprising at least one dense-phase fluidized bed. The invention can be advantageously applied to CO₂ capture and energy production.

The invention provides a fuel coal chemical looping combustion CO2 separation method in coupling with pure oxygen gasification. In a fuel reactor, a gasification agent (B) composed of water vapor and a small amount of oxygen enters from the bottom of a bed of a bubbling fluidized bed gasification furnace (1), the bed material (C) is coarse-grained inert material and performs fluidization movement under the action of the gasification agent and forms a dense phase zone; fine powdered coal (A) is added into the bubbling fluidized bed gasification furnace (1) from the dense phase zone and performs gasification reaction with the gasification agent (B), so as to form coal gas and unburned carbon (D); oxygen carrier particle (E) enters from the bottom of a lifting pipe (2) and reacts with the combustible components such as CO, H2 and CH4 in the coal gas, so as to generate CO2 and H2O. The flue gas composed of CO2, water vapor, uncompleted burned combustible gas and tiny amount of carbon-containing fine fly ash enters into a reburning chamber (13), wherein the combustible gas and the carbon in the fine fly ash perform combustion reaction with oxygen (J) from an oxygen inlet (14) of the reburning chamber, so as to generate CO2 and H2O.

The invention relates to the technical fields of energy sources and environment and discloses chemical power poly-generation energy system and method for recycling CO2. In the system, coal gas obtained by gasifying a carbon-rich raw material, and a hydrogen-rich raw material, namely, coke oven gas, are mixed and subjected to a reforming reaction and a chemical synthesis reaction to obtain a reaction product, the reaction product is processed in a flash evaporation process and a rectification process for separation to obtain CO2 gas and a final product, one part of the CO2 gas separated from a rectifying tower is delivered to take part in the gasification process of the carbon-rich raw material, and the other part of the CO2 is delivered to take part in the reforming reaction. By means of the system and the method provided by the invention, the CO2 separated in the rectifying process is used as feed gas to be directly recycled by the system so that a water gas shift reaction, chemical-looping combustion and other methods with higher energy-consumption performance for improving the chemical concentration of the CO2 are avoided, the problems of reduced energy system efficiency caused by the separation of CO2 and difficulties in transporting and storing large amount of CO2 are solved, and thus, a dual-effect production mode for energy-saving and environmental-protection utilization of resources is realized.

The invention discloses a device for separating carbon dioxide through chemical-looping combustion in a coal pressurizing high-density recirculating fluidized bed. Gasification reaction is carried out on coal particles and a gasification agent in a pressurizing high-density recirculating fluidized bed fuel reactor 1; and a gasification product and an oxygen carrier returning back to the fuel reactor 1 performs redox reaction to generate CO2 and H2O. The device comprises the pressurizing high-density recirculating fluidized bed fuel reactor (1), a primary cyclone separator (2), a primary dipleg (3), a fresh oxygen carrier particle feeder (4), a cross flow moving bed air reactor (5), a grid plate (6), an inactivation oxygen carrier discharging device (7), a primary material returner (8), a primary exhaust pipe (9), a secondary cyclone separator (10), a secondary exhaust pipe (11), a secondary dipleg (12) and a secondary material returner (13). By using the device in the invention, the reaction matching problem caused by the quantity grade difference existing in combustion and the oxygen carrier reaction rate is solved, thus the combustion efficiency of the coal, the separated CO2 concentration and the final gathering rate of the CO2 are greatly improved.

The invention discloses an indirect intermediate-temperature chemical energy storage device for solar heat on the basis of chemical-looping combustion. The indirect intermediate-temperature chemical energy storage device comprises parabolic trough condensers, line-focus reinforced heat collecting tubes, a shell and tube heat collecting reactor, a heat collecting fluid regulating valve, a heat collecting fluid standby storage tank, a gas-solid oxidation reactor, a gas distributing board, a gas-solid heat exchange device, a gas-solid separating device and a pressure pump. The line-focus reinforced heat collecting tubes and the shell and tube heat collecting reactor are connected with the pressure pump, the shell and tube heat collecting reactor and a return valve are connected with the gas-solid oxidation reactor, and the gas-solid oxidation reactor, the gas-solid separating device and the gas-solid heat exchange device are connected with the shell and tube heat collecting reactor. When solar energy is unavailable or the irradiation intensity of the solar energy is insufficient, the line-focus reinforced heat collecting tubes, the heat collecting fluid regulating valve, the heat collecting fluid standby storage tank and the shell and tube heat collecting reactor are connected with the pressure pump. The collected solar heat is stored in a metallic solid fuel form by the indirect intermediate-temperature chemical energy storage device, and the indirect intermediate-temperature chemical energy storage device has the advantages of high energy storage density, simple structure, flexibility in regulation and control and the like.

The invention relates to an oxygen carrier for methane chemical looping combustion and a preparation method for the oxygen carrier. The oxygen carrier comprises Fe2O3, Al2O3, CeO2 and KNO3, wherein the mass ratio of the KNO3 to the (CeO2 + Fe2O3 + Al2O3) is (1-10)%: (99-90)%; the mass ratio of the CeO2 to the (Fe2O3 + Al2O3) is (1-20) %: (99-80)%; and the mass ratio of the Fe2O3 to the Al2O3 is (10-60) %: (90-40)%. The method comprises the following steps of: preparing a nitrate solution, adding aqueous ammonia serving as a precipitant for co-precipitation, performing suction filtration, washing, roasting, soaking in a potassium nitrate solution, drying, roasting, and thus obtaining the oxygen carrier for methane chemical looping combustion. The oxygen carrier has high CH4 conversion rate and quick conversion rate in full conversion reaction of methane, the reaction is full, the CO2 concentration of the product is high, and the method for preparing the oxygen carrier is simple and facilitates industrialization.

The invention discloses a method for producing and heating a gas agent which contains carbon fuel and a device thereof, pertaining to the gasification field of fuels containing carbon. Parts of syngas generated by a gasifier is combusted through chemical-looping combustion and the heat generated therefrom is recovered in a heat exchanger network, and under the condition that external H2O and/or CO2 is added, the H2O and CO2 mixed gas at enough high temperature and as large as possible flow is obtained and used as the gas agent; when the gas agent is lack of heat and has too low fractional conversion, O2 is transferred to the gas agent from gas containing the O2 through a peroxy-separator. The gas agent obtained by the method is sent to a ground gasifier or an underground gasifier to react with the fuels containing the carbon, and the syngas containing no N2 is obtained. By adjusting the composition of the gas agent, the composition of the syngas can be adjusted flexibly according to downstream requirements; the discharge of CO2 is low during the whole gasification process; the method relies little on environment and after a gasification system starts and works normally, the syngas can be obtained through the gasification of the fuels containing the carbon so as to provide energy for continuous production, and obtained intermediate material flow is favorable for doping the O2 into the gasifier.

The invention belongs to the technical field of chemical-looping combustion, and particularly relates to a magnetic oxygen carrier based solid fuel chemical-looping combustion system and technology. The system is based on the characteristic that during the oxidation-reduction reaction of an iron-based oxygen carrier, Fe2O3 in high valence state is nonmagnetic and Fe3O4 in low valence state is magnetic; and electromagnetic control devices are adopted to separate an oxygen carrier with Fe3O4 in low valence state from a fuel reactor and send the oxygen carrier to an air reactor, meanwhile separate an oxygen carrier with Fe2O3 in high valence state from the air reactor and sent the oxygen carrier to the fuel reactor, so that the chemical-looping combustion of coal, biological substances and other solid fuels is realized. Through adopting an electromagnetic separation device, the system not only realizes the efficient separation of the oxygen carrier and solid particles such as unburned solid fuels and burnout ash residues during the direct chemical-looping combustion of solid fuel, but also realizes the effective separation of Fe2O3 in high valence state and Fe3O4 in low valence state, so that the oxygen carrier is efficiently and fully utilized.

The invention belongs to the technical field of chemical looping hydrogen, and discloses supported nickel tungsten bimetallic composite oxide and a preparation method and an application thereof. A molecular formula is NiyW1O3+y/Al2O3, y is 0.3-1; the preparation method comprises the following steps: completely mixing nickel nitrate hexahydrate, tungsten hexachloride and aluminum nitrate nonahydrate in ethanol according to proportion and then dissolving the materials; then dropping a NaOH aqueous solution and mixing with a mixture, after standing, performing centrifugal filtration on a flocculent precipitate and washing the material; and drying and roasting the material to obtain the product. The supported nickel tungsten bimetallic composite oxide can be used for tribed self-heating gasification with light alkane, and reforming and direct production of hydrogen and carbon dioxide. The advantages of chemical looping combustion, catalytic reforming and high purity hydrogen production by pyrolysis water, and self-heating reforming of a gas-solid counter current operation-type tribed reactor are combined, the coprecipitation preparation method having the advantages of simple operation and low cost is used, so that fuel can be directly converted to carbon dioxide and high purity hydrogen, and near-zero energy consumption in-situ separation of the product is realized.

The invention provides a chemical looping combustion device and method based on a tower bubbling fluidized bed fuel reactor. The device is a circulating loop composed of an air reactor, an air cyclone separator, a return feeder, the tower fuel reactor, a fuel cyclone separator and an isolator. The method includes the steps that fuel in the tower fuel reactor sequentially upward passes through small chambers divided by multiple independent air distribution partition boards in the height direction to be subjected to deep oxidation reaction with oxidation state oxygen carriers, the mixture is converted into CO2 and H2O to be discharged, reduction state oxygen carriers enter the air reactor through the fuel cyclone separator and the isolator for oxygen carrier regenerative reaction to generate oxidation state oxygen carriers, and the oxidation state oxygen carriers are separated through the air cyclone separator and then enter the fuel reactor through the return feeder; solid fuel is subjected to gasification reaction in the small chamber on the lower portion of the fuel reactor and then is subjected to oxidation reaction. By means of the device and method, the air-solid flow state in the fuel reactor can be effectively improved, and chemical looping combustion efficiency is improved.