CO2 capture and dry reforming conversion integrated reaction system for coupling biogas and boiler flue gas

Abstract

The utility model discloses a CO2 capture and dry reforming conversion integrated reaction system for coupling biogas and boiler flue gas, which mainly comprises a gas mixer, a first heat exchanger, a rotary capture reaction furnace, a rotary dry reforming reaction furnace, a biogas storage tank and a coal-fired boiler flue gas pipeline, the gas mixer is used for preliminarily mixing flue gas and biogas to provide stable and continuous reaction gas; the first heat exchanger realizes simultaneous proceeding of trapping and conversion reactions between double reactors of the rotary trapping reaction furnace and the rotary dry reforming reaction furnace, and realizes gas heat exchange; meanwhile, calcium carbonate generated by the rotary trapping reaction furnace and calcium oxide generated by the rotary dry reforming reaction furnace can be mutually utilized; and low-energy-consumption reaction is realized between the two reactors through a heat pump system. According to the invention, CO2-containing coal-fired boiler flue gas is reacted with biogas, the reaction waste heat is fully utilized, and the energy consumption of the calcium cycle carbon dioxide capture and conversion integrated system is reduced.

Description

Technical Field

[0001] This utility model belongs to the technical field of integrated carbon dioxide capture and conversion, and more specifically, relates to an integrated reaction system for CO2 capture and dry reforming conversion that couples biogas and boiler flue gas. Background Technology

[0002] Since the Industrial Revolution, the massive emissions of greenhouse gases such as CO2 and CH4 have exacerbated the ecological problems caused by the greenhouse effect. Against this backdrop, reducing and controlling greenhouse gas emissions is of paramount importance.

[0003] In my country's energy structure, coal consumption still accounts for more than 50%, and the total carbon dioxide emissions from the thermal power generation industry are enormous. Therefore, carbon dioxide capture of exhaust gases from coal-fired power plants remains a key focus. At the same time, the fermentation of domestic and industrial waste produces a large amount of methane mixtures. The method of purifying and burning these mixtures for power generation is inefficient. Therefore, the efficient utilization of methane in biogas is also a key focus.

[0004] Calcium oxide carbon capture and methane dry reforming are important technological pathways for achieving efficient carbon treatment and methane utilization, respectively. Their main reactions include:

[0005] CaO + CO2 → CaCO3 ΔH 0 = -178.32 kJ / mol (collection)

[0006] CO2 + CH4 → 2CO + 2H2 ΔH 0 = +247 kJ / mol (dry reforming)

[0007] Among these, the Ca-based carbon capture reaction has a wide reaction temperature range and already has practical applications; however, the large amount of heat released during the reaction cannot be fully utilized. The dry reforming reaction, on the other hand, has a higher initial reaction temperature and requires the absorption of a large amount of heat, resulting in high energy consumption. Therefore, to improve the efficiency and reduce energy consumption of this pathway, an integrated technology pathway of carbon capture and dry reforming conversion under the calcium cycle is proposed, with the main reactions as follows:

[0008] CaCO3 + CH4 → CaO + 2CO + 2H2 ΔH 0 = +425.32 kJ / mol (calcium cycle dry reforming)

[0009] Currently, there is relatively little research on the process flow of the aforementioned technical route. Chinese utility model patent CN116062688A discloses a solar-driven biogas dry reforming hydrogen production system, proposing a methane dry reforming system powered by solar energy. It uses pressure swing separation to separate CO2 from biogas and generated gas, thereby adjusting the CH4 / CO2 mixing ratio to prevent carbon buildup, and utilizes solar energy for heating, providing a new approach to system construction. However, its system energy consumption remains relatively high. Utility Model Content

[0010] In view of the above-mentioned defects or improvement needs of the existing technology, this utility model provides an integrated reaction system for CO2 capture and dry reforming conversion that couples biogas and boiler flue gas. Its purpose is to combine CO2 capture and CO2 dry reforming conversion, thereby solving the technical problems of high energy consumption and low energy utilization rate of carbon dioxide capture and dry reforming conversion system.

[0011] To achieve the above objectives, this utility model provides an integrated CO2 capture and dry reforming reaction system coupling biogas and boiler flue gas, comprising a gas mixer, a first heat exchanger, a rotary capture reactor, a rotary dry reforming reactor, a biogas storage tank, and a coal-fired boiler flue gas pipeline; the coal-fired boiler flue gas pipeline and the biogas storage tank are both connected to the inlet of the gas mixer, the outlet of the gas mixer is connected to the inlet of the tube layer of the first heat exchanger through a first pipeline, the outlet of the tube layer of the first heat exchanger is connected to the inlet of the rotary capture reactor, the outlet of the rotary capture reactor is connected to the inlet of the rotary dry reforming reactor through a second pipeline, the outlet of the rotary dry reforming reactor is connected to the inlet of the shell layer of the first heat exchanger, and the outlet of the shell layer of the first heat exchanger is connected to a third pipeline to discharge gaseous reaction products.

[0012] Preferably, the rotary collecting reactor contains granular particles of a mixture of calcium oxide and catalyst; the rotary dry reforming reactor contains granular particles of a mixture of calcium carbonate and catalyst.

[0013] Preferably, the catalyst is independently selected from one or more of nickel, cobalt, ruthenium, platinum, palladium, and rhodium.

[0014] Preferably, the gas mixer includes a biogas inlet, a flue gas inlet, a mixer cavity, a metal corrugated pipe, a base, and a gas distributor; the flue gas pipeline of the coal-fired boiler is connected to the flue gas inlet, and the biogas storage tank is connected to the biogas inlet; the metal corrugated pipe is located on the inner wall of the mixer cavity.

[0015] Preferably, the gas distributor is a tubular structure with one end open and the other end closed, and is located inside the mixer cavity; the open end of the gas distributor is nested inside the biogas inlet, and slots are provided on the pipe wall of the gas distributor near the closed end.

[0016] Preferably, the mixer cavity is cylindrical, and the centerline of the flue gas inlet is tangent to the cross-sectional circle of the mixer cavity.

[0017] Preferably, the discharge port of the rotary collecting reactor is connected to a first particle screener, and the discharge port of the rotary dry reforming reactor is connected to a second particle screener; the first particle screener is connected to a fourth pipe and a fifth pipe, the fourth pipe and the fifth pipe are respectively connected to the inlet of the calcium carbonate silo and the powder granulation and regeneration device, and the powder granulation and regeneration device is connected to the inlet of the calcium carbonate silo; the second particle screener is connected to a sixth pipe and a seventh pipe, the sixth pipe and the seventh pipe are respectively connected to the inlet of the calcium oxide silo and the powder granulation and regeneration device, and the powder granulation and regeneration device is connected to the calcium oxide silo.

[0018] Preferably, the outlets of the calcium oxide chamber and the calcium carbonate chamber are both connected to the inlet of the particle suction device, and the outlets of the particle suction device are respectively connected to the feed inlet of the rotary collection reactor and the feed inlet of the rotary dry reforming reactor.

[0019] Preferably, the system further includes a second heat exchanger, the tube side of which is connected to the sixth pipe, and the shell side of which is connected to the second pipe; the second pipe is also connected to a gas analyzer.

[0020] Preferably, the rotary trapping reactor and the rotary dry reforming reactor are connected by a heat pump.

[0021] In summary, compared with the prior art, the above-described technical solution conceived by this utility model can achieve the following beneficial effects:

[0022] 1. This utility model is equipped with a rotary capture reactor and a rotary dry reforming reactor. The two reactors operate simultaneously, with the CaO phase particle carbon capture reaction and the CaCO3 phase particle dry reforming reaction proceeding synchronously. After each reaction, the particles are switched between the two reactors through a particle circulation system. This system can effectively reduce heat loss caused by the temperature switching between the capture and dry reforming reactions in a single reactor, ensuring the continuity and stability of the system's operation. Furthermore, the heat released from the capture reaction can be fully utilized through a heat pump heat exchanger.

[0023] 2. This utility model adds storage tanks for CaO phase and CaCO3 phase particles. On the one hand, it plays a buffering role in the particle circulation and transportation. By adjusting the power of the suction and discharge equipment, the mass flow rate of the particles can be further adjusted to adapt to changes in working conditions. On the other hand, the rotary collection reactor converts calcium oxide into calcium carbonate, and the rotary dry reforming reactor converts calcium carbonate into calcium oxide. The products of the two reactions are reactants of the other reaction, realizing particle recycling and regeneration, which facilitates the reuse of re-granulated CaO phase and CaCO3 phase particles.

[0024] 3. This utility model incorporates a first heat exchanger, a second heat exchanger, and a heat pump to achieve heat recovery and reuse. Specifically, the first heat exchanger uses the high-temperature syngas generated by the reaction to preheat the unreacted mixed reaction gas, thus utilizing the waste heat of the syngas; the second heat exchanger uses the high-temperature CaO phase particles output from the rotary dry reforming reactor to heat the collected mixed gas, thus utilizing the waste heat of the high-temperature materials; the heat pump collects the low-temperature heat released by the capture reaction, processes it, and converts it into high-temperature heat to power the rotary dry reforming reactor, fully utilizing the heat released by the capture reaction.

[0025] 4. The advantage of the gas mixer of this utility model having its centerline of the flue gas inlet tangent to the cross-sectional circle of the mixer cavity is that tangential entry makes it easier for the flue gas to form a vortex in the mixer cavity, entraining the biogas entering from the biogas inlet, and increasing the mixing time of the two gases in the cavity, making the gas mixing more thorough; the advantage of setting a gas distributor is that it buffers the axially entering biogas, and the biogas escapes from the slot holes on the gas distributor, which is easier to be entrained and mixed by the flue gas compared to the axial intake method, causing less damage to the vortex, extending the mixing time, and further improving the thoroughness of the mixing; the metal bellows is set to guide the vortex, making the mixing more thorough.

[0026] 5. This utility model sets up a mixed gas flow valve and a synthesis gas flow valve, and uses the mixed gas flow valve and the synthesis gas flow valve to control the flow rate of the mixed gas in the pipeline and the synthesis gas in the cavity, so that the two gases can fully exchange heat in the first heat exchanger, reduce the waste heat loss of the synthesis gas, preheat the mixed gas in advance, and reduce energy consumption. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the integrated reaction system for CO2 capture and dry reforming conversion based on coupled biogas and boiler flue gas of this utility model.

[0028] Figure 2 This is a schematic diagram of the structure of the gas mixer of this utility model.

[0029] Figure 3 This is a schematic diagram of the rotary carbon capture reactor of this utility model.

[0030] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1. Gas mixer; 101. Biogas inlet; 102. Flow monitor; 103. Flue gas inlet; 104. Mixer cavity; 105. Metal bellows; 106. Gas outlet; 107. Base; 108. Gas distributor; 2. First heat exchanger; 3. Rotary collection reactor; 301. Inlet; 302. Outlet; 303. Transmission mechanism; 304. Cylinder; 305. Inlet; 306. Outlet; 4. Gas analyzer; 5. Rotary dry reforming reactor; 6. Biogas storage tank; 7. Fuel... 8. Coal-fired boiler flue gas duct; 9. Biogas flow valve; 10. Eighth duct; 11. Calcium oxide silo; 12. Calcium carbonate silo; 13. Mixed gas flow valve; 14. Syngas flow valve; 15. Second heat exchanger; 16. Heat pump; 17. First duct; 18. Inlet of the tube layer; 19. Outlet of the tube layer; 20. Second duct; 21. Inlet of the shell layer; 22. Outlet of the shell layer; 23. Third duct; 24. First powder sieve; 25. Second powder sieve; 26. Fourth duct; 27. Fifth duct; 28. Powder granulation and regeneration device; 29. ​​Sixth duct; 30. Seventh duct; 31. Particle suction device. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model. Furthermore, the technical features involved in the various embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0032] This utility model provides an integrated CO2 capture and dry reforming reaction system coupling biogas and boiler flue gas, including a gas mixer 1, a first heat exchanger 2, a rotary capture reactor 3, a rotary dry reforming reactor 5, a biogas storage tank 6, and a coal-fired boiler flue gas pipeline 7. The coal-fired boiler flue gas pipeline 7 and the biogas storage tank 6 are both connected to the inlet of the gas mixer 1. The outlet 106 of the gas mixer 1 is connected to the inlet 17 of the tube layer of the first heat exchanger 2 through a first pipeline 16. The outlet 18 of the tube layer of the first heat exchanger 2 is connected to the inlet of the rotary capture reactor 3. The outlet of the rotary capture reactor 3 is connected to the inlet of the rotary dry reforming reactor 5 through a second pipeline 19. The outlet of the rotary dry reforming reactor 5 is connected to the inlet 20 of the shell layer of the first heat exchanger 2. The outlet 21 of the shell layer of the first heat exchanger 2 is connected to a third pipeline 22 to discharge gaseous reaction products.

[0033] In some embodiments, the rotary trapping reactor 3 contains granular particles of a mixture of calcium oxide and a catalyst; the rotary dry reforming reactor 5 contains granular particles of a mixture of calcium carbonate and a catalyst; preferably, the catalyst is selected from one or more of nickel, cobalt, ruthenium, platinum, palladium, and rhodium;

[0034] In some embodiments, the gas mixer 1 comprises a biogas inlet 101, a flue gas inlet 103, a mixer cavity 104, a metal corrugated pipe 105, a base 107, and a gas distributor 108. The flue gas pipeline 7 of the coal-fired boiler is connected to the flue gas inlet 103, and the biogas storage tank 6 is connected to the biogas inlet 101. The metal corrugated pipe 105 is located on the inner wall of the mixer cavity 104 and is used to guide the vortex of the initially mixed gas in the mixer cavity 104, thereby increasing the mixing time of the flue gas and biogas. The gas distributor 108 is a tubular structure with one end open and the other end closed, and is located inside the mixer cavity 104. The open end of the gas distributor 108 is nested inside the biogas inlet 101, and slots 109 are provided on the pipe wall of the gas distributor 108 near the closed end.

[0035] In some embodiments, the mixer cavity 104 is cylindrical, and the centerline of the flue gas inlet 103 is tangent to the cross-sectional circle of the mixer cavity 104.

[0036] In some embodiments, to avoid obstruction of flow within the gas mixer 1, the flue gas inlet pipe is deviated towards the outlet direction, with an angle between 5-15° and the perpendicular direction of the mixer cavity 104.

[0037] In some embodiments, the discharge port of the rotary collection reactor 3 is connected to a first particle screen 23, and the discharge port of the rotary dry reforming reactor 5 is connected to a second particle screen 24; the first particle screen 23 is connected to a fourth pipe 25 and a fifth pipe 26, the fourth pipe 25 and the fifth pipe 26 are respectively connected to the inlet of the calcium carbonate silo 11 and the powder granulation and regeneration device 27, and the powder granulation and regeneration device 27 is connected to the inlet of the calcium carbonate silo 11; the second particle screen 24 The sixth pipe 28 and the seventh pipe 29 are connected. The sixth pipe 28 and the seventh pipe 29 are respectively connected to the inlet of the calcium oxide silo 10 and the powder granulation and regeneration device 27. The powder granulation and regeneration device 27 is connected to the calcium oxide silo 10. The outlet of the calcium oxide silo 10 and the outlet of the calcium carbonate silo 11 are both connected to the inlet of the particle suction device 30. The outlet of the particle suction device 30 is respectively connected to the feed inlet of the rotary collection reactor 3 and the feed inlet of the rotary dry reforming reactor 5.

[0038] In some embodiments, the first powder sieve 23 and the second powder sieve 24 contain inclined filter screens. Uncrushed CaCO3 particles and spherical CaO particles pass through the filter screens and enter the calcium carbonate silo 11 and the calcium oxide silo 10 from the outlets of the first powder sieve 23 and the second powder sieve 24, respectively. Crushed powder leaks from the filter screens into the powder outlets of the first powder sieve 23 and the second powder sieve 24. After collection, it is re-granulated by the powder granulation and regeneration device 27 and transported to the calcium carbonate silo 11 and the calcium oxide silo 10, respectively. It is then re-intake into the feed inlets of the rotary dry reforming reactor 5 and the rotary collection reactor 3, respectively, to achieve material circulation.

[0039] In some embodiments, a second heat exchanger 14 is also included, wherein the tube side of the second heat exchanger 14 is connected to the sixth pipe 28, and the shell side of the second heat exchanger 14 is connected to the second pipe 19; the CaO solid particles discharged from the dry reforming reactor 5 have a large amount of waste heat, and the gas discharged from the rotary trapping reactor 3 exchanges heat with the CaO solid particles in a countercurrent manner between the second heat exchanger 14, thereby preheating the gas discharged from the rotary trapping reactor 3 and reducing the waste heat loss of the particles.

[0040] In some embodiments, the second pipe 19 is also connected to a gas analyzer 4, which monitors the CO2 content in the gas exiting the rotary capture reactor 3 and transmits the information to the particle suction device 30 in real time. The particle suction device 30 adjusts its power to increase or decrease according to the CO2 content information, so as to realize the continuous capture and regeneration cycle of the system to adapt to the peak fluctuation of boiler operation.

[0041] In some embodiments, the rotary capture reactor 3 and the rotary dry reforming reactor 5 are connected by a heat pump 15 so that the CO2 capture reaction in the rotary capture reactor releases a large amount of heat, which is used for the heat required for the dry reforming reaction in the rotary dry reforming reactor. The heat pump 15 can be used to convert and utilize the stored heat.

[0042] In some embodiments, the biogas storage tank 6 and the gas mixer 1 are connected by an eighth pipe 9, and a biogas flow valve 8 is connected to the eighth pipe 9.

[0043] In some embodiments, a flow monitor 102 is installed on the pipe of the flue gas inlet 103 to monitor the flue gas flow of the coal-fired boiler and automatically adjust the biogas flow valve 8 to control the biogas inlet flow and achieve a mixing ratio of CH4 and CO2 of 0.8 to 1.2.

[0044] In some embodiments, a mixed gas flow valve 12 is provided on the first pipeline 16. When the flue gas flow fluctuates, the flow detector 102 can control the opening of the mixed gas flow valve 12 to achieve stable operation of the reaction system. A syngas flow valve 13 is provided on the third pipeline 22. By coupling the syngas flow valve 13 with the mixed gas flow valve 12, the residence time of the mixed gas and syngas in the first heat exchanger can be adjusted, thereby adjusting the amount of heat exchange between the mixed gas and syngas to reduce waste heat loss and achieve preheating of the mixed gas.

[0045] In some embodiments, the rotary trapping reactor 3 and the rotary dry reforming reactor 5 have the same structure, specifically:

[0046] It includes an air inlet 301, a discharge outlet 302, a transmission mechanism 303, a cylinder 304, a feed inlet 305, and an air outlet 306; the air inlet 301 and the discharge outlet 302 are located at one end of the cylinder 304, and the feed inlet 305 and the air outlet 306 are located at the other end of the cylinder 304; the transmission mechanism 303 is disposed in the middle of the cylinder 304 and is used to rotate the cylinder 304; a stirring plate is also disposed inside the cylinder 304.

[0047] In some embodiments, both the rotary trapping reactor 3 and the rotary dry reforming reactor 5 are placed at an incline towards the discharge port. The particles are poured in from the feed port 305. During the stirring process, the reaction mixture particles slowly move towards the discharge port 302. During the stirring process, the particles after the trapping reaction or dry reforming conversion are poured out from the discharge port 302.

[0048] Example 1

[0049] This embodiment provides an integrated reaction system for CO2 capture and dry reforming conversion of coupled biogas and boiler flue gas, such as... Figure 1As shown, the system includes a gas mixer 1, a first heat exchanger 2, a rotary trap reactor 3, a rotary dry reforming reactor 5, a biogas storage tank 6, and a coal-fired boiler flue gas pipeline 7. The coal-fired boiler flue gas pipeline 7 and the biogas storage tank 6 are both connected to the inlet of the gas mixer 1. The outlet 106 of the gas mixer 1 is connected to the inlet 17 of the tube layer of the first heat exchanger 2 via a first pipeline 16. The outlet 18 of the tube layer of the first heat exchanger 2 is connected to the inlet of the rotary trap reactor 3. The outlet of the rotary trap reactor 3 is connected to the inlet of the rotary dry reforming reactor 5 via a second pipeline 19. The outlet of the rotary dry reforming reactor 5 is connected to the inlet 20 of the shell layer of the first heat exchanger 2. The outlet 21 of the shell layer of the first heat exchanger 2 is connected to a third pipeline 22 to discharge gaseous reaction products. The rotary collection reactor 3 contains granular particles of a mixture of calcium oxide and nickel; the rotary dry reforming reactor 5 contains granular particles of a mixture of calcium carbonate and nickel.

[0050] The gas mixer 1 includes a biogas inlet 101, a flow monitor 102, a flue gas inlet 103, a mixer cavity 104, a metal corrugated pipe 105, a base 107, and a gas distributor 108. The flue gas pipeline 7 of the coal-fired boiler is connected to the flue gas inlet 103, and the biogas storage tank 6 is connected to the biogas inlet 101. The metal corrugated pipe 105 is located on the inner wall of the mixer cavity 104. The gas distributor 108 is a tubular structure with one end open and the other end closed, and is located inside the mixer cavity 104. The open end of the gas distributor 108 is nested inside the biogas inlet 101, and a slot 109 is provided on the pipe wall of the gas distributor 108 near the closed end. The mixer cavity 104 is cylindrical, and the centerline of the flue gas inlet 103 is tangent to the cross-sectional circle of the mixer cavity 104.

[0051] The discharge port of the rotary collection reactor 3 is connected to the first particle screen 23, and the discharge port of the rotary dry reforming reactor 5 is connected to the second particle screen 24. The first particle screen 23 is connected to the fourth pipe 25 and the fifth pipe 26. The fourth pipe 25 and the fifth pipe 26 are respectively connected to the inlet of the calcium carbonate silo 11 and the powder granulation and regeneration device 27. The powder granulation and regeneration device 27 is connected to the inlet of the calcium carbonate silo 11. The second particle screen 24 is connected to the sixth pipe 28 and the seventh pipe 29. The sixth pipe 28 and the seventh pipe 29 are respectively connected to the inlet of the calcium oxide silo 10 and the powder granulation and regeneration device 27. The powder granulation and regeneration device 27 is connected to the calcium oxide silo 10.

[0052] The outlets of the calcium oxide chamber 10 and the calcium carbonate chamber 11 are both connected to the inlet of the particle suction device 30. The outlets of the particle suction device 30 are respectively connected to the feed inlet of the rotary trapping reactor 3 and the feed inlet of the rotary dry reforming reactor 5. A second heat exchanger 14 is also included. The tube side of the second heat exchanger 14 is connected to the sixth pipe 28, and the shell side of the second heat exchanger 14 is connected to the second pipe 19. The second pipe 19 is also connected to a gas analyzer 4. The rotary trapping reactor 3 and the rotary dry reforming reactor 5 are connected by a heat pump 15.

[0053] The working principle of this utility model's integrated CO2 capture and dry reforming reaction system coupling biogas and boiler flue gas is as follows: Flue gas from a coal-fired boiler containing carbon dioxide and methane from a biogas storage tank are both transported to a gas mixer to mix and form a mixed reaction gas. This mixed reaction gas is then transported through a first pipeline to the inlet of the tube layer of a first heat exchanger. After heat exchange, it is output from the outlet of the tube layer of the first heat exchanger and then introduced into a rotary capture reactor, where the carbon dioxide in the mixed gas is captured and converted into calcium carbonate, specifically: CaO + CO2 → CaCO3. The reaction from the rotary capture reactor... The discharged mixed gas is introduced into a rotary dry reforming reactor through a second pipe to carry out a dry reforming reaction, in which methane and uncaptured carbon dioxide in the mixed gas are converted into gaseous reaction products of carbon monoxide and hydrogen. The specific reaction is: CaCO3 + CH4 → CaO + 2CO + 2H2. A gas analyzer is connected to the second pipe to analyze the carbon dioxide content in the gas discharged from the rotary trapping reactor. The gaseous reaction products are fed into the shell of the first heat exchanger and discharged through the outlet of the shell of the first heat exchanger via a third pipe. The solid components after the reaction in the rotary trap reactor are fed into the first particle separator. The sieved powder is fed into the powder granulation and regeneration device through the fifth pipe for regranulation, and then fed into the calcium carbonate chamber. The sieved mixture particles are fed directly into the calcium carbonate chamber through the fourth pipe. The calcium carbonate and catalyst mixture particles in the calcium carbonate chamber are then pumped into the rotary dry reforming reactor for continued recycling through a particle suction device. The solid components after the reaction in the rotary dry reforming reactor are fed into the second particle separator. The sieved powder is fed into the powder granulation and regeneration device through the seventh pipe for regranulation, and then fed into the calcium oxide chamber. The sieved mixture particles are fed directly into the calcium oxide chamber through the sixth pipe. The calcium carbonate and catalyst mixture particles in the calcium oxide chamber are then pumped into the rotary trap reactor for continued recycling through a particle suction device. The solid components discharged from the sixth pipe after the reaction are exchanged with the gas components discharged from the outlet of the rotary trap reactor through a second heat exchanger to increase the temperature of the gas components discharged from the outlet of the rotary trap reactor; the rotary trap reactor and the rotary dry reforming reactor are connected through a heat pump.

[0054] Based on this system, a test bench was constructed, including a rotary trapping reactor, a rotary dry reforming reactor, a CaO phase particle storage tank, and a CaCO3 phase particle storage tank. The rotary reactor chamber has a diameter of 50 mm and a length of 1000 mm. The instruments are connected via material transport pipes. The feed rates of the CaO and CaCO3 phase particles are M. granBoth flow rates are 1 kg / min; the two reactors are connected by a gas supply pipe. At the start of the reaction, a mixture of simulated flue gas and biogas (CH4 volume fraction 12%, CO2 volume concentration 15%, and the remaining component is N2) is introduced, with a total flow rate of 1 L / min, i.e., the initial volumetric flow rate V of CH4. 0,CH4 =0.12L / min, V 0，CO2 =0.15 L / min; the temperature of the trapping reaction chamber is 500℃, and the temperature of the dry reforming reaction chamber is 720℃. During the reaction, a CO2 volumetric flow meter is installed in both the trapping reactor and the dry reforming reaction to measure the CO2 volumetric flow rate V in the mixed gas after trapping. int,CO2 A flow meter and an infrared analyzer were connected to the gas outlet of the dry reforming reactor to measure the residual CH4 and CO2 volumetric flow rates in the syngas, which were V and V, respectively. 1,CH4 With V 1,CO2 CO2 capture capacity (m) CO2 CH4 conversion rate α CH4 CO2 conversion rate α CO2 It can be calculated using the following formula:

[0055]

[0056] In this reaction system, the CO2 capture rate reaches 12.55 mmol / g, and the CH4 and CaCO3 conversion rates can reach up to approximately 65% ​​and 71%, respectively, at 720℃.

[0057] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An integrated reaction system for CO2 capture and dry reforming of biogas and boiler flue gas, characterized in that, The system includes a gas mixer (1), a first heat exchanger (2), a rotary trapping reactor (3), a rotary dry reforming reactor (5), a biogas storage tank (6), and a coal-fired boiler flue gas pipeline (7). The coal-fired boiler flue gas pipeline (7) and the biogas storage tank (6) are both connected to the inlet of the gas mixer (1). The outlet (106) of the gas mixer (1) is connected to the inlet (17) of the tube layer of the first heat exchanger (2) via a first pipeline (16). The outlet (18) of the tube layer of the device (2) is connected to the inlet of the rotary trap reactor (3). The outlet of the rotary trap reactor (3) is connected to the inlet of the rotary dry reforming reactor (5) through the second pipe (19). The outlet of the rotary dry reforming reactor (5) is connected to the inlet (20) of the shell layer of the first heat exchanger (2). The outlet (21) of the shell layer of the first heat exchanger (2) is connected to the third pipe (22) to discharge the gaseous reaction products.

2. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 1, characterized in that, The rotary trapping reactor (3) contains granular particles of a mixture of calcium oxide and catalyst; the rotary dry reforming reactor (5) contains granular particles of a mixture of calcium carbonate and catalyst.

3. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 2, characterized in that, The catalysts are each independently selected from one or more of nickel, cobalt, ruthenium, platinum, palladium, and rhodium.

4. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 1, characterized in that, The gas mixer (1) includes a biogas inlet (101), a flue gas inlet (103), a mixer cavity (104), a metal corrugated pipe (105), a base (107), and a gas distributor (108); the flue gas pipeline (7) of the coal-fired boiler is connected to the flue gas inlet (103), and the biogas storage tank (6) is connected to the biogas inlet (101); the metal corrugated pipe (105) is located on the inner wall of the mixer cavity (104).

5. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 4, characterized in that, The gas distributor (108) is a tubular structure with one end open and the other end closed, and is located inside the mixer cavity (104); the open end of the gas distributor (108) is nested inside the biogas inlet (101), and slots (109) are provided on the pipe wall of the gas distributor (108) near the closed end.

6. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 4, characterized in that, The mixer cavity (104) is cylindrical, and the center line of the flue gas inlet (103) is tangent to the cross-sectional circle of the mixer cavity (104).

7. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 2, characterized in that, The discharge port of the rotary collection reactor (3) is connected to the first particle screener (23), and the discharge port of the rotary dry reforming reactor (5) is connected to the second particle screener (24). The first particle screener (23) is connected to the fourth pipe (25) and the fifth pipe (26). The fourth pipe (25) and the fifth pipe (26) are respectively connected to the inlet of the calcium carbonate silo (11) and the powder granulation regeneration device (27). The powder granulation regeneration device (27) is connected to the inlet of the calcium carbonate silo (11). The second particle screener (24) is connected to the sixth pipe (28) and the seventh pipe (29). The sixth pipe (28) and the seventh pipe (29) are respectively connected to the inlet of the calcium oxide silo (10) and the powder granulation regeneration device (27). The powder granulation regeneration device (27) is connected to the calcium oxide silo (10).

8. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 7, characterized in that, The outlets of the calcium oxide chamber (10) and the calcium carbonate chamber (11) are both connected to the inlet of the particle suction device (30), and the outlets of the particle suction device (30) are respectively connected to the feed inlet of the rotary collection reactor (3) and the feed inlet of the rotary dry reforming reactor (5).

9. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 7, characterized in that, It also includes a second heat exchanger (14), the tube side of which is connected to the sixth pipe (28), and the shell side of which is connected to the second pipe (19); the second pipe (19) is also connected to a gas analyzer (4).

10. The integrated reaction system for CO2 capture and dry reforming of coupled biogas and boiler flue gas as described in claim 1, characterized in that, The rotary trap reactor (3) and the rotary dry reforming reactor (5) are connected by a heat pump (15).

Images