Device and method for extracting gas by low-carbon synergistic utilization of high and low concentrations
阅读说明：本技术 一种低碳协同利用高低浓度抽采瓦斯的装置及方法 (Device and method for extracting gas by low-carbon synergistic utilization of high and low concentrations ) 是由 刘方 宋晨 杨丽 宋正昶 翟成 赵江源 吴鑫 亢炜燎 贾志轩 于 2021-08-12 设计创作，主要内容包括：一种低碳协同利用高低浓度抽采瓦斯的装置及方法,步骤如下：将高浓度瓦斯通入燃料反应器,与燃料反应器中的载氧体反应使载氧体还原；还原后的载氧体送入空气反应器内部,同时通入低浓度瓦斯,与还原后的载氧体反应使载氧体氧化,氧化后的载氧体在低浓度瓦斯的带动下送入气固分离器,气固分离器分离后的气体排空,固体载氧体送入燃烧反应器；燃烧反应器中生成的烟气送入纯氧补燃装置,同时纯氧补燃装置通入混合空分装置制备的纯氧和来自冷凝装置冷凝后的CO-(2)的预混配气系统,使烟气充分燃烧,燃烧气进入冷凝装置进行冷凝,冷凝后的CO-(2)冷凝气送入CO-(2)捕集装置,冷凝水排出。本发明不仅实现了瓦斯的能量利用,同时能够低成本捕集CO-(2)。(A device and a method for extracting gas by low-carbon cooperative utilization of high and low concentrations comprise the following steps: introducing high-concentration gas into the fuel reactor, and reacting the high-concentration gas with an oxygen carrier in the fuel reactor to reduce the oxygen carrier; feeding the reduced oxygen carrier into an air reactor, introducing low-concentration gas, reacting with the reduced oxygen carrier to oxidize the oxygen carrier, feeding the oxidized oxygen carrier into a gas-solid separator under the drive of the low-concentration gas, emptying the gas separated by the gas-solid separator, and feeding the solid oxygen carrier into a combustion reactor; the flue gas generated in the combustion reactor is sent into a pure oxygen afterburning device, and simultaneously, the pure oxygen afterburning device is introduced into pure oxygen prepared by a mixed air separation device and CO condensed by a condensing device 2 The premixing gas distribution system ensures that the flue gas is fully combusted, the combustion gas enters the condensing device for condensation, and the condensed CO 2 Feeding the condensed gas into CO 2 And a trap device for discharging the condensed water. The invention not only realizesThe energy utilization of the gas and the low-cost CO capture 2 。)
1. A low-carbon high-low concentration gas extraction device capable of realizing synergistic utilization is characterized by comprising low-concentration gas and high-concentration gasGas, oxygen carrier, air reactor, fuel reactor, gas-solid separator, pure oxygen after-combustion device, condensing device, CO2The fuel reactor comprises a fuel reactor main body provided with a heating device, an oxygen carrier inlet arranged at the edge of the top end of the fuel reactor main body, a gas outlet arranged at the center of the top end of the fuel reactor main body, an oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body, a high-concentration gas inlet arranged at the bottom end of the fuel reactor main body, a gas distribution plate arranged at the bottom of the fuel reactor main body, and a solid feed inlet arranged on the side wall of the fuel reactor main body and above the gas distribution plate, wherein high-concentration gas enters the fuel reactor through the high-concentration gas inlet, and the oxygen carrier is placed in the fuel reactor main body through the solid feed inlet;
the air reactor comprises an air reactor main body provided with a heating device, a low-concentration gas inlet arranged at the bottom end of the air reactor main body, a gas distribution plate arranged at the bottom of the air reactor main body, an oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body and an air flow outlet arranged at the top of the air reactor main body, wherein the oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body is connected with an oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body through a pipeline, the oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body is higher than the oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body, and low-concentration gas enters the air reactor through the low-concentration gas inlet;
the gas-solid separator comprises a gas-solid separator body, a material inlet arranged at the top of the side wall of the gas-solid separator body, a gas outlet arranged at the top of the gas-solid separator body and a solid outlet arranged at the bottom of the gas-solid separator body, wherein the material inlet arranged at the top of the side wall of the gas-solid separator body is connected with an airflow outlet pipeline arranged at the top of the air reactor main body, and the solid outlet arranged at the bottom of the gas-solid separator body is connected with an oxygen carrier inlet pipeline arranged at the edge of the top of the fuel reactor main body;
the pure oxygen afterburning device comprises a closed combustion chamber, a flue gas inlet arranged at the top end of the combustion chamber, a combustion-supporting gas inlet arranged on the side wall of the combustion chamber close to the top end and a gas outlet arranged at the bottom of the combustion chamber, wherein the flue gas inlet arranged at the top end of the combustion chamber is connected with a gas outlet pipeline arranged at the center of the top end of the fuel reactor main body;
the condensing device comprises a condenser body, a gas inlet to be condensed and a condensed gas outlet, wherein the gas inlet to be condensed is connected with a gas outlet pipeline arranged at the bottom of the combustion chamber, the condensed gas outlet is divided into two paths, and one path is connected with CO2The other path is connected with a premixing gas distribution system CO2The air inlet is connected with a pipeline;
the premixing gas distribution system comprises a closed mixing chamber and CO arranged on the side wall of the mixing chamber2The mixed gas outlet is connected with a combustion-supporting gas inlet pipeline in the pure oxygen afterburning device;
the air separation device is used for separating oxygen from air, and an oxygen outlet of the air separation device is connected with an oxygen inlet pipeline arranged at the bottom end of the mixing chamber.
2. The low-carbon and high-concentration gas extraction device capable of utilizing synergistically according to claim 1, wherein combustible gas CH is arranged on a pipeline connecting the air reactor and the gas-solid separator, a pipeline connecting the combustion chamber and the pure oxygen afterburning device and a pipeline connecting the pure oxygen afterburning device and the condensing device4、H2CO and O2A sensor probe and a temperature thermocouple.
3. The low-carbon and high-concentration gas extraction device capable of realizing synergistic utilization according to claim 1, wherein a particle circulation control device and an isolator are arranged on a pipeline connecting the air reactor and the fuel reactor.
4. The low-carbon and high-concentration gas extraction device capable of realizing synergistic utilization according to claim 1, wherein temperature thermocouples are arranged at the upper, middle and lower parts in the air reactor and the fuel reactor.
5. The low-carbon and high-concentration gas extraction device capable of realizing synergistic utilization according to claim 1, characterized in that the pure oxygen afterburning device comprises four combustion-supporting gas inlets which are uniformly arranged on the same horizontal plane and are positioned on the side wall of the combustion chamber and close to the top end.
6. The low-carbon and high-concentration gas extraction device capable of realizing synergistic utilization of the gas is disclosed by claim 1, wherein the oxygen carrier is an Fe-based, Al-based, Cu-based, Mn-based, Ni-based, Co-based or Ce-based oxide oxygen carrier.
7. The low-carbon and high-concentration gas extraction device capable of realizing synergistic utilization of gas according to claim 1, wherein the oxygen carrier is Fe2O3/Al2O3The particle size of the composite material oxygen carrier is 106-355 mu m.
8. The low-carbon and high-concentration gas extraction device capable of realizing synergistic utilization is disclosed by claim 1, and is characterized in that the preparation method of the oxygen carrier is as follows: mixing micron-sized Fe2O3With nanoscale Al2O3The mass ratio of the particles is 1:1, putting the mixture into a beaker filled with equivalent deionized water, uniformly stirring the mixture at a rotating speed of 200-300 r/min, putting the sample into a drying oven, and keeping the temperature of 100-110 ℃ until the water is completely evaporated; placing the dried sample in a muffle furnace, and setting the calcining procedure of the muffle furnace as follows: raising the temperature from room temperature to 650-950 ℃ at a temperature raising rate of less than or equal to 5 ℃/min, then raising the temperature from 650-950 ℃ to 1000-1400 ℃ at a temperature raising rate of less than or equal to 2 ℃/min, preserving the temperature at 1000-1400 ℃ for 120-360 min, then lowering the temperature from 1000-1400 ℃ to 650-950 ℃ at a temperature lowering rate of less than or equal to 2 ℃/min, and finally lowering the temperature from 650-950 ℃ to room temperature at a temperature lowering rate of less than or equal to 5 ℃/min; and (3) crushing and sieving the calcined sample by using a small crusher, and selecting particles with the particle size of 106-355 mu m as an oxygen carrier OC required by the reaction.
9. The method of claim 1The method for extracting the gas by the device through low-carbon cooperative utilization of high and low concentrations is characterized by comprising the following steps: introducing high-concentration gas into the fuel reactor, and reacting the high-concentration gas with an oxygen carrier in the fuel reactor to reduce the oxygen carrier; the reduced oxygen carrier is fed into the air reactor, low-concentration gas is introduced into the bottom of the air reactor, the low-concentration gas reacts with the reduced oxygen carrier to oxidize the oxygen carrier, and the low-concentration gas is catalytically oxidized into CO2The oxidized oxygen carrier is driven by low-concentration gas flow to be sent into a gas-solid separator, gas separated by the gas-solid separator is emptied, and the solid oxygen carrier is sent into a combustion reactor; the flue gas generated in the combustion reactor is sent into a pure oxygen afterburning device, and simultaneously, the pure oxygen afterburning device is introduced into pure oxygen prepared by a mixed air separation device and CO condensed by a condensing device2The mixed gas of the pre-mixing gas distribution system ensures that the flue gas is fully combusted, the combustion gas enters a condensing device for condensation, and the condensed CO2Feeding the condensed gas into CO2And a trap device for discharging the condensed water.
10. The method for extracting gas with low carbon and high and low concentration by synergistic utilization according to claim 9, characterized in that CH in the high-concentration gas4The concentration exceeds 90 percent, and CH in the low-concentration extracted gas is4The concentration is lower than 1.5%, the amount of the oxygen carrier is larger than that of methane, and when the amount of the methane entering the reactor is 1mol, the amount of the oxygen carrier is at least 12 mol.
Technical Field
The invention relates to the technical field of coal mine production, in particular to a device and a method for extracting gas by low-carbon synergistic utilization of high and low concentrations.
Background
Coal bed gas, commonly known as "gas", is a hydrocarbon gas produced with coal and contains CH as the main component4. In the coal mine production process, due to different extraction modes and discharge positions, CH in the coal bed gas4The content of the (A) is greatly different, such as CH in gas of a ground drilling extraction goaf and a pressure relief coal seam4The concentration of CH in ventilation gas (ventilation gas) is usually 30-95%4The concentration is even less than 1%. Wherein CH4The part with the concentration higher than 30 percent can be effectively utilized by the conventional combustion technology, such as gas power generation, a gas boiler, alumina roasting, coal slime drying and the like. On the other hand, the explosion limit of methane is 5% -16% under normal pressure, and CH is caused by lack of mature and effective low-concentration gas recycling technology4The part with a concentration below 6% will usually be diluted to below 1% and directly discharged to the atmosphere, resulting in a waste of a lot of clean energy and environmental damage. The existing low-concentration gas utilization technology mainly comprises the following steps: the post-combustion technology of high concentration gas is mixed. However, the efficiency of the combustor can be seriously influenced by using the technology because the concentration of methane in the low-concentration gas frequently fluctuates; ② the concentration increasing technology of low-concentration gas, and the concentration of methane is increased by methods of membrane separation, pressure swing adsorption and the like. The method has high engineering cost, is still in a laboratory research stage, and cannot be generally popularized; ③ thermal oxidation and catalytic oxidation technologyBy maintaining a higher temperature level in the oxidation bed, methane is promoted to be oxidized in the oxidation bed to generate CO2And H2And O. The technology establishes an industrial operation demonstration device, has good development prospect, but needs to add catalyst into a reactor additionally to reduce the temperature required by the reaction. In addition, the catalyst has the problems of high cost and easy activation.
The raw coal yield is 39 hundred million tons in 2020 years in China, the gas extraction utilization rate is 44.8 percent, and the air discharge amount reaches 7.28 hundred million m3At a gas density of 0.718kg/m3Calculated, equivalent to 52.3 ten thousand tons of CH4，CH4The Global Warming Potential (GWP) is CO2If the part is CH 21 times4Complete catalytic oxidation, equivalent to CO reduction21046 ten thousand tons of discharge; most of the existing utilization technologies for high-concentration extracted gas are mature, and CH can be efficiently utilized4Gas extracted at a concentration of 30% or more, for example, gas for power generation, as a chemical raw material, an industrial fuel, etc., but CH4Is still converted into CO after being utilized2Discharging into the atmosphere, additionally adding CO2The purification and trapping device can also greatly increase the construction cost.
For low concentration gas, CH4The ventilation air methane with the concentration lower than 1 percent still lacks of mature and effective utilization technology, and although the ventilation air methane countercurrent oxidation technology and the blending combustion power generation technology establish exemplary projects at present, the ventilation air methane countercurrent oxidation technology and the blending combustion power generation technology are still not widely applied due to the problems of immature technology, high cost and the like.
Chinese patent CN112178460A discloses a high-low concentration gas mixing system and a gas mixing process control method thereof, which comprises a high concentration gas pump station, a low concentration gas pump station, a gas mixing device and a control system, wherein the high concentration gas is mixed with the low concentration gas or air, so that the gas supply concentration is automatically adjusted and is suitable for the high-low concentration unit;
chinese patent CN211316202U discloses a coal mine gas combustion device with extremely low concentration, which comprises a combustion chamber, an air inlet, an air outlet, a cooling mechanism, a purification mechanism, a detection communicating pipe, an elastic air bag and the like, and achieves the purpose of purifying the burned gas before the gas is discharged to the outside.
The above patent realizes the combustion utilization of high and low concentration gas, but does not relate to the discharge of CO after the gas is combusted2The cost is relatively high, and the low-concentration gas is not fully utilized.
Disclosure of Invention
The technical problem to be solved is as follows: aiming at the problems in the prior art, the invention provides a device and a method for extracting gas by low-carbon synergistic utilization of high and low concentrations, which can enable CH (CH) to be utilized4The gas with the concentration of less than 1.5 percent is sufficiently catalyzed and oxidized to realize CH4To CO2And can achieve CO2Low cost capture.
The technical scheme is as follows: a low-carbon high-low concentration gas extraction device cooperatively utilizing high and low concentrations comprises low-concentration gas, high-concentration gas, an oxygen carrier, an air reactor, a fuel reactor, a gas-solid separator, a pure oxygen afterburning device, a condensing device, CO2The fuel reactor comprises a fuel reactor main body provided with a heating device, an oxygen carrier inlet arranged at the edge of the top end of the fuel reactor main body, a gas outlet arranged at the center of the top end of the fuel reactor main body, an oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body, a high-concentration gas inlet arranged at the bottom end of the fuel reactor main body, a gas distribution plate arranged at the bottom of the fuel reactor main body, and a solid feed inlet arranged on the side wall of the fuel reactor main body and above the gas distribution plate, wherein high-concentration gas enters the fuel reactor through the high-concentration gas inlet, the oxygen carrier is placed in the fuel reactor main body through the solid feed inlet, and the bottom of the fuel reactor main body is provided with the gas distribution plate;
the air reactor comprises an air reactor main body provided with a heating device, a low-concentration gas inlet arranged at the bottom end of the air reactor main body, a gas distribution plate arranged at the bottom of the air reactor main body, an oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body and an air flow outlet arranged at the top of the air reactor main body, wherein the oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body is connected with an oxygen carrier outlet pipeline (sealed) arranged at the bottom of the side wall of the fuel reactor main body, the oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body is higher than the oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body, low-concentration gas enters the air reactor through the low-concentration gas inlet, and the bottom of the air reactor main body is provided with the gas distribution plate;
the gas-solid separator comprises a gas-solid separator body, a material inlet arranged at the top of the side wall of the gas-solid separator body, a gas outlet arranged at the top of the gas-solid separator body and a solid outlet arranged at the bottom of the gas-solid separator body, wherein the material inlet arranged at the top of the side wall of the gas-solid separator body is connected with an airflow outlet pipeline arranged at the top of the air reactor main body, and the solid outlet arranged at the bottom of the gas-solid separator body is connected with an oxygen carrier inlet pipeline arranged at the edge of the top of the fuel reactor main body;
the pure oxygen afterburning device comprises a closed combustion chamber, a flue gas inlet arranged at the top end of the combustion chamber, a combustion-supporting gas inlet arranged on the side wall of the combustion chamber close to the top end and a gas outlet arranged at the bottom of the combustion chamber, wherein the flue gas inlet arranged at the top end of the combustion chamber is connected with a gas outlet pipeline arranged at the center of the top end of the fuel reactor main body;
the condensing device comprises a condenser body, a gas inlet to be condensed and a condensed gas outlet, wherein the gas inlet to be condensed is connected with a gas outlet pipeline arranged at the bottom of the combustion chamber, the condensed gas outlet is divided into two paths, and one path is connected with CO2The other path is connected with a premixing gas distribution system CO2The air inlet is connected with a pipeline;
the premixing gas distribution system comprises a closed mixing chamber and CO arranged on the side wall of the mixing chamber2The gas inlet, locate the oxygen import of mixing chamber bottom and locate the gas mixture export at mixing chamber top, the gas mixture export is connected with combustion-supporting gas inlet pipeline in the pure oxygen afterburning device, and the setting of gas distribution system in advance is in order to guarantee the safety of pure oxygen afterburning device, and the high-purity CO of extraction part through the condensation2With O produced by an air separation plant2Introducing the premixed mixture into a pure oxygen afterburning device (carbon dioxide): the volume ratio of pure oxygen is 80: about 20, namely the concentration of pure oxygen introduced into the pure oxygen afterburning device is equal to or slightly lower than that in air);
the air separation device (which separates oxygen from air by using a low-temperature freezing principle and is a common commercial product) is used for separating oxygen from air, and an oxygen outlet of the air separation device is connected with an oxygen inlet pipeline arranged at the bottom end of the mixing chamber.
Preferably, the pipeline for connecting the air reactor and the gas-solid separator, the pipeline for connecting the combustion chamber and the pure oxygen afterburning device and the pipeline for connecting the pure oxygen afterburning device and the condensing device are provided with combustible gas CH4、H2CO and O2The device comprises a sensor probe and a temperature thermocouple, wherein the sensor probe and the temperature thermocouple are connected with a PLC control system, and the state and the temperature of gas in a pipeline are monitored and controlled through the PLC control system.
Preferably, a particle circulation control device and an isolator are arranged on a pipeline connected with the air reactor and the fuel reactor, and the particle circulation control device and the isolator are used for supplying fluidized air to one side of the air reactor in an auxiliary mode to prevent gas and particles from flowing back from the air reactor to the fuel reactor.
Preferably, temperature thermocouples are arranged at the upper part, the middle part and the lower part in the air reactor and the fuel reactor.
Preferably, the gas-solid separator is a cyclone separator, the material inlet is connected with the airflow outlet of the air reactor by adopting a flange seal pipeline, after gas-solid separation, the gas is discharged to the atmosphere through the gas outlet, and the solid particles are discharged to the fuel reactor through the solid outlet.
Preferably, the pure oxygen afterburning device comprises four combustion-supporting gas inlets which are uniformly arranged on the same horizontal plane and are positioned on the side wall of the combustion chamber and close to the top end, and an ignition device is arranged in the combustion chamber.
Preferably, the oxygen carrier is an Fe, Al, Cu, Mn, Ni, Co or Ce based oxide oxygen carrier.
Preferably, the oxygen carrier is Fe2O3/Al2O3An oxygen carrier of composite material with a particle size of 106-355 μm。
Preferably, the preparation method of the oxygen carrier comprises the following steps: mixing micron-sized Fe2O3With nanoscale Al2O3Mixing the particles according to the mass ratio of 1:1, putting the mixture into a beaker filled with equivalent deionized water, uniformly stirring the mixture at the rotating speed of 200-300 r/min, putting the sample into a drying oven, and keeping the temperature of 100-110 ℃ until the water is completely evaporated; placing the dried sample in a muffle furnace, and setting the calcining procedure of the muffle furnace as follows: raising the temperature from room temperature to 650-950 ℃ at a temperature raising rate of less than or equal to 5 ℃/min, then raising the temperature from 650-950 ℃ to 1000-1400 ℃ at a temperature raising rate of less than or equal to 2 ℃/min, preserving the temperature at 1000-1400 ℃ for 120-300 min, then lowering the temperature from 1000-1400 ℃ to 650-950 ℃ at a temperature lowering rate of less than or equal to 2 ℃/min, and finally lowering the temperature from 650-950 ℃ to room temperature at a temperature lowering rate of less than or equal to 5 ℃/min; and (3) crushing and sieving the calcined sample by using a small crusher, and selecting particles with the particle size of 106-355 mu m as an oxygen carrier OC required by the reaction.
The method for extracting the gas by low-carbon cooperative utilization of high and low concentrations based on the device comprises the following steps: introducing high-concentration gas into the fuel reactor, and reacting the high-concentration gas with an oxygen carrier in the fuel reactor to reduce the oxygen carrier; the reduced oxygen carrier is fed into the air reactor, low-concentration gas is introduced into the bottom of the air reactor, the low-concentration gas reacts with the reduced oxygen carrier to oxidize the oxygen carrier, and the low-concentration gas is catalytically oxidized into CO2The oxidized oxygen carrier is sent into a gas-solid separator under the drive of low-concentration gas, the gas separated by the gas-solid separator is emptied, and the solid oxygen carrier is sent into a combustion reactor; the flue gas generated in the combustion reactor is sent into a pure oxygen afterburning device, and simultaneously, the pure oxygen afterburning device is introduced into pure oxygen prepared by a mixed air separation device and CO condensed by a condensing device2The mixed gas in the pre-mixing gas distribution system ensures that the flue gas is fully combusted, the combustion gas enters a condensing device for condensation, and the condensed CO2Feeding the condensed gas into CO2And a trap device for discharging the condensed water.
Preferably, CH is contained in the high-concentration gas4The concentration exceeds 90 percent, and CH in the low-concentration extracted gas is4At a concentration of less than1.5 percent, the amount of the oxygen carrier is more than that of methane, and when the amount of the methane entering the reactor is 1mol, the amount of the oxygen carrier is at least 12 mol.
Has the advantages that: the method not only realizes the energy utilization of the gas, but also can trap CO at low cost2. The invention utilizes the characteristics of clean, efficient and flameless Combustion of Chemical-Looping Combustion (CLC) technology and is based on CH4The catalytic oxidation mechanism can completely catalyze and burn the ventilation air methane. The invention can realize CO2Internal separation, the whole system not only realizes the energy utilization of gas, but also can capture CO at low cost2。
In an air reactor, CH4The gas with the concentration of less than 1.5 percent is sufficiently catalyzed and oxidized to realize CH4To CO2The complete conversion of the methane is realized, the air emission of the low-concentration gas extracted from the coal mine is reduced by less than 1.5%, the greenhouse effect is reduced, and meanwhile, the overall thermal efficiency of the chemical-looping combustion device can be effectively improved by the heat released in the methane catalytic oxidation process, so that the recycling of clean energy is realized; in the fuel reactor, CH4The gas with the concentration higher than 90 percent is fully combusted, and CO in the flue gas at the outlet of the fuel reactor2The concentration can reach more than 80-90 percent, and CO is realized2Low cost capture.
Compared with a thermal oxidation and catalytic oxidation device, the method adopts the oxygen carrier as a multifunctional carrier, fully utilizes the strong catalytic oxidation capacity and the heat transfer and storage characteristics of the oxygen carrier, and plays a role in catalyzing methane oxidation and cracking while transferring lattice oxygen between the air reactor and the reduction reactor, without additionally adding a catalyst; since the oxidation reaction process of the oxygen carrier is very fast and can be completed within a few seconds, the conventional chemical looping combustion technology (including chemical looping reforming and chemical looping decoupling combustion) usually focuses on the reaction process in the fuel reactor, and the use of low-concentration gas as reducing gas in the fuel reactor can affect CO2Efficiency of the capture system. The method uses low-concentration gas as oxidizing gas, and on one hand, the low-concentration gas is completely converted into CO2To realizeThe harmless treatment of harmful gas is realized, and on the other hand, the normal oxidation of the oxygen carrier is realized. In addition, because the oxygen carrier is always in a fluidized state, sintering, agglomeration or deactivation phenomena are less prone to occur compared with a fixed bed catalyst.
In addition, the air reactor in the CLC, like the oxidation bed in the catalytic oxidation unit, can provide the high temperature environment required for catalytic oxidation of methane; the oxygen carrier component which plays a role of transferring lattice oxygen is similar to that of the methane oxidation catalyst, and the purpose of catalyzing methane oxidation and combustion can be achieved.
Chemical looping combustion refers to the combustion process of fuel realized by cyclically alternating reactions between an air reactor and a fuel reactor through an Oxygen Carrier (OC). Wherein the OC is oxidized in an air reactor and then enters a fuel reactor to transfer lattice oxygen to the fuel, avoiding direct contact of air with the fuel. In a fuel reactor (also called a reduction reactor), the metal oxide and the fuel undergo a reduction reaction, and the fuel is oxidized to mainly produce CO2And H2O (g), the metal oxide is reduced to elemental metal (or a lower valence metal oxide), and the reaction is shown in equation (1):
（2n+m）MexOy+CnH2m→（2n+m）MexOy-1+nCO2+mH2O （1）
the elemental metal (or lower valence metal oxide) from the fuel reactor enters an air reactor (also called oxidation reactor) to be regenerated by air oxidation, and releases a large amount of heat, and the reaction is shown as equation (2):
（2n+m）MexOy-1+（n+0.5m）O2→（2n+m）MexOy （2）
equations (1), (2) add up, i.e., exactly the same as the conventional combustion equation with direct fuel and air contact:
CnH2m+（n+0.5m）O2→nCO2+mH2O （3）
OC circulates in a fuel reactor and an air reactor to realize the conversion of lattice oxygenThereby avoiding direct contact between the fuel and air. In addition, since the reaction operating temperatures in both the air reactor and the fuel reactor are relatively low, there is substantially NO thermal type NO in the air reactorxWith fast NOxGenerating; meanwhile, in the fuel reactor, the fuel is not mixed with O2Contact, NO fuel type NOxAnd (4) generating.
More importantly, the gas mixture product obtained after the reaction of the fuel reactor is condensed and separated, so that high-purity CO can be obtained at low cost2。
The gas energy utilization device not only realizes the energy utilization of gas, but also can collect CO at low cost2The low-carbon synergistic utilization of the high-concentration and low-concentration gas extraction has essential differences.
Drawings
FIG. 1 is a schematic structural diagram of a low-carbon and high-low-concentration gas extraction device for synergistic utilization according to the invention;
FIG. 2 is a schematic flow diagram of gas, solid and liquid of the low-carbon and high-concentration gas extraction device for collaborative utilization, wherein a dotted line represents a gas flow direction, and a solid line represents a solid and liquid flow direction;
FIG. 3 is a schematic diagram of the comprehensive utilization method of high-low concentration extracted gas of a coal mine;
FIG. 4 is a graph of gas conversion for 80s of air reactor operation;
in the drawings, each numerical designation represents the following: 1. low-concentration gas; 2. high-concentration gas; 3. an air reactor; 4. a fuel reactor; 5. a gas-solid separator; 6. a pure oxygen afterburning device; 7. a condensing unit; CO 82A trapping device; 9. a pre-mixing gas distribution system; 10. an air separation plant.
Detailed Description
The invention is further described below with reference to the accompanying drawings and specific embodiments.
Example 1
A low-carbon and high-low concentration gas extraction device cooperatively utilizes high and low concentrations, referring to figures 1 and 2, and comprises low-concentration gas 1, high-concentration gas 2, an oxygen carrier, an air reactor 3, a fuel reactor 4, a gas-solid separator 5 and pure gasOxygen after-combustion device 6, condensing device 7, CO2The fuel reactor 4 comprises a fuel reactor main body provided with a heating device, an oxygen carrier inlet arranged at the edge of the top end of the fuel reactor main body, a gas outlet arranged at the center of the top end of the fuel reactor main body, an oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body, a high-concentration gas inlet arranged at the bottom end of the fuel reactor main body, a gas distribution plate arranged at the bottom of the fuel reactor main body, and a solid feed inlet arranged on the side wall of the fuel reactor main body and above the gas distribution plate, wherein high-concentration gas 2 enters the fuel reactor 4 through the high-concentration gas inlet, the oxygen carrier is placed in the fuel reactor main body through the solid feed inlet, and the bottom of the fuel reactor main body is provided with the gas distribution plate; the air reactor 3 comprises an air reactor main body provided with a heating device, a low-concentration gas inlet arranged at the bottom end of the air reactor main body, a gas distribution plate arranged at the bottom of the air reactor main body, an oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body and an air flow outlet arranged at the top of the air reactor main body, wherein the oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body is connected with an oxygen carrier outlet pipeline (sealed) arranged at the bottom of the side wall of the fuel reactor main body, the oxygen carrier outlet arranged at the bottom of the side wall of the fuel reactor main body is higher than the oxygen carrier inlet arranged at the bottom of the side wall of the air reactor main body, low-concentration gas 1 enters the air reactor 3 through the low-concentration gas inlet, and the bottom of the air reactor main body is provided with the gas distribution plate; the gas-solid separator 5 comprises a gas-solid separator body, a material inlet arranged at the top of the side wall of the gas-solid separator body, a gas outlet arranged at the top of the gas-solid separator body and a solid outlet arranged at the bottom of the gas-solid separator body, wherein the material inlet arranged at the top of the side wall of the gas-solid separator body is connected with an airflow outlet pipeline arranged at the top of the air reactor body, and the solid outlet arranged at the bottom of the gas-solid separator body is connected with an oxygen carrier inlet pipeline arranged at the edge of the top of the fuel reactor body; the pure oxygen afterburning device 6 comprises a closed combustion chamber, a flue gas inlet arranged at the top end of the combustion chamber, a combustion-supporting gas inlet arranged on the side wall of the combustion chamber close to the top end and a combustion-supporting gas inlet arranged on the side wall of the combustion chamber close to the top endA gas outlet at the bottom of the combustion chamber, wherein a flue gas inlet arranged at the top end of the combustion chamber is connected with a gas outlet pipeline arranged at the center of the top end of the fuel reactor main body; the condensing device 7 comprises a condenser body, a gas inlet to be condensed and a condensed gas outlet, wherein the gas inlet to be condensed is connected with a gas outlet pipeline arranged at the bottom of the combustion chamber, the condensed gas outlet is divided into two paths, and one path is connected with CO2The trapping device 8 is connected with the other path of the gas distribution system CO2The air inlet is connected with a pipeline; the premixing gas distribution system 9 comprises a closed mixing chamber and CO arranged on the side wall of the mixing chamber2The gas inlet, locate the oxygen import of mixing chamber bottom and locate the gas mixture export at mixing chamber top, the gas mixture export is connected with combustion-supporting gas inlet pipeline in the pure oxygen afterburning device 6, and the setting of gas distribution system 9 in advance is in order to guarantee the safety of pure oxygen afterburning device 6, and the high-purity CO of extraction part through the condensation2With O produced by the air separation plant 102Introducing the premixed pure oxygen into a pure oxygen afterburning device 6 (the volume ratio of carbon dioxide to pure oxygen is about 80: 20, namely the concentration of the pure oxygen introduced into the pure oxygen afterburning device is equal to or slightly lower than that in air); the air separation unit 10 (which separates oxygen from air by using the cryogenic refrigeration principle, and is a common commercially available product) is used for separating oxygen from air, and an oxygen outlet of the air separation unit 10 is connected with an oxygen inlet pipeline arranged at the bottom end of the mixing chamber.
The method for extracting the gas by low-carbon cooperative utilization of high and low concentrations based on the device comprises the following steps: introducing high-concentration (extracted) gas 2 into a fuel reactor 4, and reacting the high-concentration (extracted) gas with an oxygen carrier in the fuel reactor 4 to reduce the oxygen carrier; the reduced oxygen carrier is sent into an air reactor 3, meanwhile, low-concentration gas 1 is introduced into the bottom of the air reactor 3, the low-concentration gas 1 reacts with the reduced oxygen carrier to oxidize the oxygen carrier, the oxidized oxygen carrier is sent into a gas-solid separator 5 under the drive of the low-concentration gas 1, the gas separated by the gas-solid separator 5 is emptied, and the solid oxygen carrier is sent into a combustion reactor 4; the flue gas generated in the combustion reactor 4 is sent into a pure oxygen afterburning device 6, and simultaneously the pure oxygen afterburning device 6 is introduced into pure oxygen prepared by a mixing air separation device 10 and CO condensed by a condensing device 72The premixing gas distribution systemThe system 9 makes the flue gas fully combusted, the combustion gas enters the condensing device 7 for condensation, and the condensed CO2Feeding the condensed gas into CO2The trap device 8 discharges the condensed water.
Example 2
The difference from the example 1 is that the pipeline connecting the air reactor 3 and the gas-solid separator 5, the pipeline connecting the combustion chamber and the pure oxygen after-combustion device 6 and the pipeline connecting the pure oxygen after-combustion device 6 and the condensing device 7 are all provided with combustible gas CH4、H2CO and O2The device comprises a sensor probe and a temperature thermocouple, wherein the sensor probe and the temperature thermocouple are connected with a PLC control system, and the state and the temperature of gas in a pipeline are monitored and controlled through the PLC control system.
And a particle circulation control device and an isolator are arranged on a pipeline connecting the air reactor 3 and the fuel reactor 4, and the particle circulation control device and the isolator are used for supplying fluidized air to one side of the air reactor 3 in an auxiliary manner to prevent gas and particles from flowing back from the air reactor to enter the fuel reactor 4.
Temperature thermocouples are arranged at the upper, middle and lower parts in the air reactor 3 and the fuel reactor 4.
The gas-solid separator 5 is a cyclone separator, the material inlet is connected with the airflow outlet of the air reactor by adopting a flange seal pipeline, after gas-solid separation, the gas is discharged to the atmosphere through the gas outlet, and the solid particles are discharged to the fuel reactor 4 through the solid outlet.
The pure oxygen afterburning device 6 comprises four combustion-supporting gas inlets which are uniformly arranged on the same horizontal plane and are positioned on the side wall of the combustion chamber and close to the top end, and an ignition device is arranged inside the combustion chamber.
The oxygen carrier is an Fe, Al, Cu, Mn, Ni, Co or Ce-based oxide oxygen carrier. In this embodiment, the oxygen carrier is Fe2O3/Al2O3The particle size of the composite material oxygen carrier is 180-270 mu m.
The preparation method of the oxygen carrier comprises the following steps: mixing micron-sized Fe2O3With nanoscale Al2O3The particles are mixed according to the mass ratio of 1:1 and then put into a beaker filled with equivalent deionized waterAfter being uniformly stirred at the rotating speed of 250r/min, the sample is placed in a drying box, and the temperature is kept at 105 ℃ until the water is completely evaporated; placing the dried sample in a muffle furnace, and setting the calcining procedure of the muffle furnace as follows: heating from room temperature to 950 ℃ at a heating rate of 5 ℃/min, then heating from 950 ℃ to 1400 ℃ at a heating rate of 2 ℃/min, preserving heat at 1400 ℃ for 300min, then cooling from 1400 ℃ to 950 ℃ at a cooling rate of 2 ℃/min, and finally cooling from 950 ℃ to room temperature at a cooling rate of 3 ℃/min; and (3) crushing and sieving the calcined sample by using a small crusher, and selecting particles with the particle size of 180-270 mu m as an oxygen carrier OC required by the reaction.
CH in the high-concentration gas 24The concentration exceeds 90 percent, and CH in the low-concentration extracted gas is4The concentration is lower than 1.5%, the amount of the oxygen carrier is larger than that of methane, and when the amount of the methane entering the reactor is 1mol, the amount of the oxygen carrier is 12 mol.
In this embodiment, the air reactor 3 is a fluidized bed reactor, specifically a cylindrical vertical riser, and has a structure from bottom to top: the bottom is a fluidization gas inlet (low-concentration gas inlet or other fluidization gas inlets), the gas distribution plate, an inclined pipeline is arranged at the position of the right side wall close to the bottom and is in flange sealing connection with the fuel reactor 4, a free airspace (particles can freely flow in the area), an airflow outlet at the top is in flange sealing connection with a material inlet of the gas-solid separator after passing through a 90-degree elbow, and the connected pipeline is provided with combustible gas (CH)4、H2、CO）、O2And the sensor probe and the temperature thermocouple are used for monitoring the components and the temperature of the gas in the pipeline.
The fuel reactor 4 is a fluidized bed reactor, specifically a cylindrical vertical down tube, and the structure from bottom to top is as follows: the bottom is a fluidizing gas inlet (a high-concentration gas inlet or other fluidizing gas inlets) and is provided with a layer of gas distribution plate, the bottom (above the gas distribution plate) is a solid discharge port (the discharge port is connected with the air reactor 3 by adopting a flange seal through an inclined pipeline, the height of two ports of the inclined pipeline is that the height of the fuel reactor 4 is higher than that of the air reactor 3, the pipeline is provided with a particle circulation control device and an isolator, and simultaneously, fluidizing air is fed to one side of the air reactor 3 in an auxiliary manner to prevent gas and particles from flowing back from the air reactor 3 to enter the fuel reactor 4), The axial symmetry position of the solid discharge port is provided with a solid feed port (the oxygen carrier is placed in the fuel reactor main body through the solid feed port), a free airspace, a flue gas outlet in the middle of the top end and an oxygen carrier inlet (oxygen carrier particles separated from the gas-solid separator enter the device from the top) arranged at the top of the side wall of the reactor.
The gas-solid separator 5 is a cyclone separator, the material inlet is hermetically connected with the gas outlet of the air reactor by adopting a flange, after gas-solid separation, the gas is discharged to the atmosphere through the gas outlet, and the solid particles are discharged to the fuel reactor 4 through the solid outlet.
The air separation plant 10 and the gas distribution system 9 in advance constitute afterburning device air supply system, and air separation plant 10 utilizes the cryogenic principle to separate the air separation plant of oxygen in the air, and afterburning device air supply system's setting is in order to guarantee the safety of pure oxygen afterburning device 6, specifically does: extracting partially condensed high purity CO2With O produced by the air separation plant 102And introducing the premixed mixture into a pure oxygen afterburning device 6 (the volume ratio of carbon dioxide to pure oxygen is 80: 20).
The pure oxygen afterburning device 6 is provided with combustible gas (CH) at the gas inlet and the gas outlet4、H2、CO）、O2The gas inlet is positioned at the top of the device, the gas outlet is positioned at the bottom of the device, in order to enable the oxygen and the gas to be mixed more uniformly, the oxygen inlet is divided into four paths, the oxygen inlets are symmetrically distributed at the position, close to the top, of the side wall of the device, the whole device is made of high-temperature-resistant steel, the top is provided with an explosion-proof valve, and the shell is wrapped by a polycrystalline mullite ceramic fiber blanket for heat preservation.
The condensing unit 7 comprises a straight glass device (air straight condensing pipe) for promoting flue gas condensation and a matched temperature-controllable circulating water cooling pump, and consists of an inner glass pipe and an outer glass pipe, wherein the cooling water flows reversely from bottom to top through an outer pipe of the glass pipes, and interfaces are arranged at two ends of the inner pipe to connect a gas circuit, so that the hotter flue gas flows through from top to bottom.
CO2The capture device 8 is mature CO based on chemical absorption2A trapping device. The above devices are all commercially available from ordinary sources unless otherwise specified.
Based on the method for extracting the gas by low-carbon synergistic utilization of high and low concentrations by the device, the fuel reactor 4 and the air reactor 3 are fluidized bed reactors. The specific operation is as follows:
(1) before the device is started, the oxygen carrier is placed on the gas distribution plate through a solid feed inlet in the fuel reactor 4, the device is started to heat up, and the temperature of the air reactor 3 and the temperature of the fuel reactor 4 are set to be stable at 950 ℃. And (2) introducing nitrogen as fluidizing gas into inlets of the two reactors at the same time when the temperature is increased, controlling the flow rate of the fluidizing gas in the fuel reactor 4 to be 0.106-0.175 m/s (the reduction of the oxygen carrier generally requires the gas-solid contact time of several minutes, so the lower flow rate is selected), and controlling the flow rate of the fluidizing gas in the air reactor 3 to be about 0.35 m/s (the oxidation reaction of the oxygen carrier only requires the time of several seconds, so the higher flow rate is selected). In order to achieve higher gas conversion efficiency, the fuel equivalence ratio is controlled to be about 2 (namely the actually introduced fuel quantity is lower than the theoretically required fuel quantity, so that the oxygen carrier is in an excessive state, and the gas can be more fully converted).
(2) After the temperature of the two reactors is stable, high-concentration coal mine is used for extracting gas (CH)4Content (wt.)>90%) as reducing gas, treated by a gas filter and a water removal device, and introduced into the reactor as high-concentration gas 2 through a gas inlet of the fuel reactor 4, wherein the reaction in the fuel reactor 4 is as follows:
·12Fe2O3+CH4→8Fe3O4+CO2+2H2O
·4Fe3O4+ CH4→12FeO+ CO2+H2O
(3) low concentration gas/ventilation gas (CH) in coal mine extracted gas4Content (wt.)<1.5%) as oxidizing gas, passing through a gas filter and a water removal deviceAfter that, as the low concentration gas 1, it enters the reactor through the gas inlet of the air reactor 3, and the reactions occurring in the air reactor 3 are:
methane cracking: CH (CH)4 →C+ 2H2
Complete catalytic combustion of methane: CH (CH)4+2O2→CO2+2H2O
Partial catalytic combustion of methane: CH (CH)4+0.5O2→CO+2H2
Complete oxidation of methane: CH (CH)4+12Fe2O3→8Fe3O4+CO2+2H2O
Partial oxidation of methane: CH (CH)4+3Fe2O3→2Fe3O4+CO+2H2
Carbon deposit combustion: c + O2→CO2
Reductive gas oxidation: h2+ O2→H2O CO+ O2→CO2
(4) The material flowing process: in the process of fluidizing OC (oxygen carrier), OC in a reduction state continuously enters the air reactor 3 through a solid discharge port of the fuel reactor 4, after the OC in the air reactor 3 is rapidly oxidized, airflow carrying OC in an oxidation state enters the gas-solid separator 5 from an outlet of the air reactor 3, gas (gas after combustion of low-concentration gas 1) is directly discharged into the atmosphere after gas-solid separation, and OC falls into the fuel reactor 4 from an outlet at the bottom of the gas-solid separator 5 (so far, one reduction-oxidation cycle is completed);
(5) gas flowing process: the high-concentration gas 2 introduced into the fuel reactor 4 reacts with the oxidation state OC, flows out through a flue gas outlet at the top of the fuel reactor 4, enters the pure oxygen after-combustion device 6, signals are transmitted to a premixing gas distribution system 9 of the pure oxygen after-combustion device 6 by an automatic control system through detecting the methane content in the flue gas entering the device, and the premixing gas distribution system 9 transmits pure oxygen capable of completely combusting the methane in the flue gas to the pure oxygen after-combustion device 6 according to the methane content in the signals (the air equivalence ratio is set to be slightly less than 1, namely the actually introduced oxygen amount is slightly larger than the theoretical oxygen amountThe amount of oxygen required for full combustion); when the outlet of the pure oxygen afterburning device 6 detects that methane still exists, a feedback signal is sent to an air separation device 10 (an oxygen generator) through the action of an automatic control system, and the air supply flow is corrected; the combusted gas enters a condensing device 7, water vapor is condensed and discharged, and CO is generated at the moment2The concentration can reach more than 80-90%, and part of the condensed gas enters CO2The other part of the trapping device 8 is drawn back by the premixing gas distribution system 9 and is re-introduced into the pure oxygen afterburning device 6 as gas distribution.
The device and the method for extracting gas by low-carbon synergistic utilization of high and low concentrations have the following specific principles, and refer to fig. 3:
(1) device based on chemical looping combustion technology for extracting high-concentration gas (CH) in gas by using coal mine4Content (wt.)>90%) as reducing gas, treated by a gas filter and a water removal device and then directly introduced into the fuel reactor 4, and the reaction is
12Fe2O3+CH4→8Fe3O4+CO2+2H2O
4Fe3O4+ CH4→12FeO+ CO2+H2O
The reduced OC enters an air reactor 3, in order to fully combust high-concentration gas, the flue gas after combustion in a fuel reactor 4 is introduced into a pure oxygen afterburning device 6, and a certain proportion of pure oxygen is provided for the pure oxygen afterburning device 6 by an air separation device 10, so that the gas is fully combusted; the gas burned by the pure oxygen afterburning device 6 enters a condensing device 7, water vapor is condensed and discharged, and CO is discharged at the moment2The concentration can reach more than 80-90%; the condensed gas enters CO2A trap device 8.
(2) Low concentration gas/ventilation gas (CH) in coal mine extracted gas4Content (wt.)<1.5%) as oxidizing gas, treated with a gas filter and a water removal device and then directly introduced into the air reactor 3, in which process possible reactions occur
Methane cracking: CH (CH)4 →C+ 2H2
Complete catalytic combustion of methane: CH (CH)4+2O2→CO2+2H2O
Partial catalytic combustion of methane: CH (CH)4+1/2O2→CO+2H2
Carbon deposit combustion: c + O2→CO2
Reductive gas oxidation: h2+ O2→H2O CO+ O2→CO2
The oxidized OC enters a gas-solid separator 5 along with the airflow, the OC enters a fuel reactor 4 after gas-solid separation, and the flue gas is directly discharged to the atmosphere.
Example 3
The difference from example 2 is that the preparation method of the oxygen carrier is as follows: mixing micron-sized Fe2O3With nanoscale Al2O3Mixing the particles according to the mass ratio of 1:1, putting the mixture into a beaker filled with equivalent deionized water, uniformly stirring the mixture at the rotating speed of 200r/min, putting the sample into a drying oven, and keeping the temperature of 100 ℃ until the water is completely evaporated; placing the dried sample in a muffle furnace, and setting the calcining procedure of the muffle furnace as follows: heating from room temperature to 650 ℃ at a heating rate of less than or equal to 5 ℃/min, then heating from 650 ℃ to 1000 ℃ at a heating rate of less than or equal to 2 ℃/min, preserving heat at 1000 ℃ for 120min, then cooling from 1000 ℃ to 650 ℃ at a cooling rate of less than or equal to 2 ℃/min, and finally cooling from 650 ℃ to room temperature at a cooling rate of less than or equal to 5 ℃/min; and (3) crushing and sieving the calcined sample by using a small crusher, and selecting particles with the particle size of 106-355 mu m as an oxygen carrier OC required by the reaction.
Example 4
The difference from example 2 is that the preparation method of the oxygen carrier is as follows: mixing micron-sized Fe2O3With nanoscale Al2O3Mixing the particles according to the mass ratio of 1:1, putting the mixture into a beaker filled with equivalent deionized water, uniformly stirring the mixture at the rotating speed of 300r/min, putting the sample into a drying oven, and keeping the temperature of 110 ℃ until the water is completely evaporated; placing the dried sample in a muffle furnace, and setting the calcining procedure of the muffle furnace as follows: heating from room temperature to 950 ℃ at a heating rate of 5 ℃/min or less, and then heating at a heating rate of 2 ℃/min or lessRaising the temperature from 950 ℃ to 1400 ℃, preserving the heat at 1400 ℃ for 300min, then reducing the temperature from 1400 ℃ to 950 ℃ according to the cooling rate of less than or equal to 2 ℃/min, and finally reducing the temperature from 950 ℃ to room temperature at the cooling rate of less than or equal to 5 ℃/min; and (3) crushing and sieving the calcined sample by using a small crusher, and selecting particles with the particle size of 106-355 mu m as an oxygen carrier OC required by the reaction.
Example 5
By adopting the device and the method in the embodiment 2, experimental tests are carried out on a small-scale serial fluidized bed device in a laboratory, the data of high-concentration and low-concentration gas extraction is from a certain coal mine in inner Mongolia, and for the convenience of the tests, the components (%) simulating the high-concentration and low-concentration gas are set as shown in the following table:
using high purity O2High purity N2High purity CO2High purity CH4The gas cylinder is used as a gas source, the flow of each gas is controlled by a mass flow meter, and each path of gas is connected through a pipeline and finally respectively introduced into the two reactors. The flow of the ventilation air methane gas is simulated to be 0.80m3H, simulating the flow of high-concentration gas to be 0.50m3The temperature of the air reactor 3 and the fuel reactor 4 was set to 950 ℃.
The experimental result shows that the air reactor 3 simulates ventilation air methane gas to realize complete conversion within 60s after the test is started (a gas conversion rate calculation method is that (the concentration of methane at the inlet of the reactor-the concentration of methane at the outlet of the reactor)/the concentration of methane at the inlet of the reactor is multiplied by 100 percent, as shown in figure 4), and meanwhile, the oxygen carrier normally completes oxidation regeneration; the conversion rate of the high-concentration gas in the fuel reactor 4 is about 53.7 percent, and the flow rate of the mixed gas conveyed by the gas supply system of the afterburning device is 0.24m3And h, the detection result of the outlet of the pure oxygen after-combustion device 6 shows that the gas is completely oxidized and combusted.