An efficient cyclic power generation system based on calcium-based chemical looping gasification for hydrogen production coupled with solid oxide fuel cell and a method for operating the same

Abstract

The present application relates to the technical field of biomass processing and hydrogen production, and particularly relates to a high-efficiency circulating power generation system based on calcium-based chemical looping gasification hydrogen production coupled with a solid oxide fuel cell and a running method thereof. The system at least comprises a gasification reactor, a third flow divider, a first back material valve, a regeneration reactor, a fourth heat exchanger, a CO2-rich flue gas conveying pipe, a flue gas purification system, a waste heat utilization boiler, a carbon capture and storage module and the like which are sequentially connected. The gasification reactor is connected with the third flow divider, and the gasification reactor is also connected with the high-temperature water vapor conveying pipe. The regeneration reactor is connected with the fourth heat exchanger. The present application realizes efficient hydrogen production and carbon capture through calcium-based chemical looping gasification technology, and combines with the solid oxide fuel cell to realize efficient power generation. The system optimizes the heat-mass balance, and improves the hydrogen production efficiency and the overall energy utilization efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biomass treatment and hydrogen production, in particular to a high-efficiency circulating power generation system based on calcium-based chemical looping gasification hydrogen production coupled with solid oxide fuel cells and an operation method thereof. BACKGROUND

[0002] With the rapid development of global economy and the continuous growth of population, energy demand continues to rise, and environmental problems are increasingly prominent. Traditional fossil energy such as coal, oil and natural gas, although in the past few decades, it has provided a large amount of energy supply for society, but the large amount of carbon emissions generated in the combustion process has seriously aggravated the global climate change and environmental pollution problems. Therefore, countries have increased the research and application of clean energy technology, and promoted the transformation of energy structure to low-carbon, clean and efficient direction. Among them, hydrogen as a clean energy carrier, has the advantages of high energy density and zero carbon emission, and is widely regarded as an important part of future energy system.

[0003] Hydrogen production technology is the core of hydrogen energy industry. Traditional hydrogen production methods such as water electrolysis, coal gasification and natural gas reforming, although to some extent, meet the market demand, but there are great limitations in energy efficiency and carbon emissions. In recent years, chemical looping gasification technology as a new hydrogen production method has gradually attracted attention. Calcium-based chemical looping gasification technology uses calcium-based materials as oxygen carriers to achieve efficient fuel gasification without external oxygen supply, and can capture carbon dioxide in the gasification process to reduce greenhouse gas emissions, with significant environmental advantages. However, this technology still faces challenges in system integration, reaction control and energy management in practical application, and needs to be further optimized and improved.

[0004] Solid oxide fuel cell is a kind of high-efficiency electrochemical energy conversion device, which can directly convert the chemical energy of hydrogen and other fuels into electrical energy, with high efficiency and low emission. Under high temperature working conditions, solid oxide fuel cell can utilize high temperature waste heat to improve overall energy utilization efficiency. Combining calcium-based chemical looping gasification hydrogen production with solid oxide fuel cell to build a combined power generation system can not only realize efficient hydrogen production, but also convert hydrogen into electricity, thereby optimizing energy utilization and helping low-carbon transformation. In summary, the combined power generation system of calcium-based chemical looping gasification and solid oxide fuel cell has broad application prospect and strategic significance, and provides important technical support for future clean energy solutions.

[0005] The present application relates to a kind of based on calcium-based chemical chain gasification hydrogen production and solid oxide fuel cell combined power generation cycle power generation system.The system is realized by calcium-based material as oxygen carrier and carbon dioxide adsorbent, efficient, low emission hydrogen production, and hydrogen is directly converted into electric energy by solid oxide fuel cell.It can overcome the defects of traditional power generation system: (1) low energy utilization efficiency, it is difficult to realize multi-stage utilization;(2) serious environmental pollution, high greenhouse gas emissions;While bringing three big advantages: (1) system integration multi-stage energy utilization, high thermal efficiency, waste heat is effectively utilized;(2) through efficient exhaust gas purification and carbon capture, the unity of hydrogen production and environmental protection target is realized;(3) calcium-based adsorbent can be recycled, improve the utilization rate of resources. SUMMARY

[0006] To solve the problems of prior art, the present application provides a kind of based on calcium-based chemical chain gasification hydrogen production coupling solid oxide fuel cell's efficient cycle power generation system and its operating method.The present application mainly realizes efficient, clean hydrogen production and electric energy conversion by integrating calcium-based chemical chain gasification technology and solid oxide fuel cell technology.Calcium-based material is used as oxygen carrier, hydrogen is efficiently generated in gasification reaction, and carbon dioxide is captured, which significantly reduces greenhouse gas emissions.Solid oxide fuel cell directly converts the chemical energy of hydrogen into electric energy and generates a large amount of waste heat, which further improves energy utilization efficiency through waste heat recovery.

[0007] The technical solutions provided by the present application are as follows:

[0008] An efficient cycle power generation system based on calcium-based chemical chain gasification hydrogen production coupling solid oxide fuel cell, characterized in that it comprises at least a gasification reactor, a third diverter, a first return valve, a regeneration reactor, a fourth heat exchanger, a CO2-rich flue gas conveying pipe, a flue gas purification system, a waste heat utilization boiler and a carbon capture and storage module, which are sequentially connected.

[0009] Based on the above technical solutions:

[0010] Biomass enters the gasification reactor, and after pyrolysis, gasification and reforming in the gasification reactor, the crude synthesis gas forms hydrogen-rich synthesis gas after passing through the third diverter and the purification system;

[0011] The calcium-based adsorbent enters the regeneration reactor for calcination and regeneration, enters the gasification reactor through the fourth diverter and the second return valve, promotes the high-temperature steam reforming reaction of biomass and the catalytic cracking of tar, releases heat, and after capturing CO2, together with the residual coke particles, enters the regeneration reactor through the third diverter and the first return valve for regeneration and releases the CO2 carried by itself.

[0012] The CO2-rich flue gas generated by the regeneration reactor enters the waste heat utilization boiler after passing through the flue gas purification system, and finally enters the carbon capture and storage module.

[0013] In the above technical solution, the following main reactions occur in the gasification reactor between the biomass and the calcium-based sorbent:

[0014] (1) Biomass → H2 + CO + CH4 + tar + carbon

[0015] (2) C + H2O → H2 + CO

[0016] (3) CaO + H2O + tar → CaCO3 + H2

[0017] (4) CaO + CO2 → CaCO3

[0018] The main reactions in the regeneration reactor are:

[0019] (1) CaCO3 → CaO + CO2

[0020] Further, the regeneration reactor is connected to the first material return valve, the oxygen outlet, the calcium-based sorbent conveyor, and the fourth heat exchanger, and the first material return valve is connected to the third diverter, and the oxygen outlet is connected to the first heat exchanger and the air compressor.

[0021] Based on the above technical solution, the calcium-based sorbent enters the regeneration reactor for calcination and regeneration, passes through the fourth heat exchanger and the second material return valve into the gasification reactor, promotes the high-temperature steam reforming reaction of biomass and the catalytic cracking of tar, and releases heat, and the generated calcium carbonate enters the regeneration reactor through the first material return valve to be reconverted into calcium oxide and release high-concentration CO2;

[0022] The rectified oxygen is reheated to room temperature by the first heat exchanger and is drawn out from the oxygen outlet, and part of the drawn-out oxygen is used for the combustion of coke in the regeneration reactor, and the other part enters the air compressor.

[0023] Further, the system further comprises a purification system, a hydrogen-rich synthesis gas conveying pipe, a solid oxide fuel cell anode, a fourth diverter, a combustion chamber, and a high-temperature flue gas conveying pipe connected in sequence, and the solid oxide fuel cell anode is connected to the solid oxide fuel cell cathode and the fourth diverter.

[0024] Based on the above technical solution, the following main reactions occur in the solid oxide fuel cell:

[0025] (1) Anode: H2 + O 2- → H2O + 2e -

[0026] (2) Cathode: 1 / 2O2 + 2e - → O 2-

[0027] (3) Overall electrochemical reaction: 1 / 2O2 + H2 → H2O

[0028] The hydrogen-rich synthesis gas generated by the purification system enters the anode of the solid oxide fuel cell, and hydrogen and oxygen undergo electrochemical reactions on the electrode to generate electricity, and the generated high-temperature steam and other synthesis gas components not involved in the reaction are divided by the fourth heat exchanger.

[0029] Further, the power generation system provided by the present application at least comprises the following steps:

[0030] The biomass enters the gasification reactor, and after pyrolysis, gasification and reforming in the gasification reactor, the hydrogen-rich synthesis gas is formed after passing through the third diverter and the purification system;

[0031] The calcium-based adsorbent enters the regeneration reactor for calcination and regeneration, and enters the gasification reactor through the fourth diverter and the second return valve to promote the high-temperature steam reforming reaction of biomass and the catalytic cracking of tar, and release heat, and after capturing CO2, it enters the regeneration reactor together with the residual coke particles through the third diverter and the first return valve for regeneration and release of the CO2 molecules carried by itself;

[0032] The CO2-rich flue gas generated by the regeneration reactor enters the waste heat utilization boiler after passing through the flue gas purification system, and finally enters the CCS.

[0033] Based on the above technical solutions, the following effects can be achieved:

[0034] Based on the catalytic effect of the calcium-based adsorbent, the high-temperature steam reforming reaction of biomass in the gasification reactor and the catalytic cracking of tar are realized, which provides heat for the reaction and improves the hydrogen-rich content of the synthesis gas;

[0035] Based on the calcination and regeneration process of the regeneration reactor, the calcium-based adsorbent is reused, the efficiency of the gasification reaction is improved, and the CO2 molecules carried by itself are released;

[0036] Based on the treatment effect of the flue gas purification system, the purification and recovery of the CO2-rich flue gas are realized, which provides flue gas meeting environmental standards for waste heat utilization and CCS, and realizes higher energy utilization efficiency and emission reduction targets.

[0037] Further, the power generation system power generation method further comprises the following steps: clean air enters the first heat exchanger through the booster, and then is divided into the lower column of the rectification tower and the upper column of the rectification tower, forming nitrogen, dirty nitrogen and high-purity oxygen, part of the oxygen is used for the combustion of coke in the regeneration reactor, and the other part enters the solid oxide fuel cell through the air compressor.

[0038] Based on the above technical scheme, the double-tower device used in the cryogenic air separation device can prepare high-purity oxygen for the chemical chain gasification hydrogen production module and the solid oxide fuel cell as an oxidizing agent reaction.

[0039] Further, the power generation system and the power generation method further include the following steps: the hydrogen-rich synthesis gas passes through the anode of the solid oxide fuel cell, the solid oxide fuel cell converts chemical energy into electrical energy, the unreacted hydrogen and other synthesis gas components enter the combustion chamber for combustion and energy release, and the generated high-temperature flue gas enters the waste heat boiler through the gas turbine;

[0040] The water pump gives water after the waste heat utilization boiler, which is heated to high-temperature steam, drives the steam turbine to generate electricity, and the outlet high-temperature steam enters the gasification reactor as a gasification medium for the gasification reaction of solid waste, and the remaining part enters the low-temperature steam turbine to further drive the steam turbine to generate electricity.

[0041] Based on the above technical scheme, the following effects can be achieved:

[0042] Based on the action of the solid oxide fuel cell, the chemical energy in the hydrogen-rich synthesis gas is efficiently converted into electrical energy, and the unreacted hydrogen and other synthesis gas components enter the combustion chamber for combustion, and the released energy is further converted into electrical energy and high-temperature flue gas through the gas turbine. These high-temperature flue gas is recovered through the waste heat boiler, thereby realizing efficient utilization of comprehensive energy and emission reduction targets;

[0043] Based on the action of the waste heat utilization boiler, the waste heat in the high-temperature flue gas is recovered and converted into high-temperature steam, which drives the steam turbine to generate electricity, and the remaining part is used as a gasification medium in the gasification reactor to promote the gasification reaction of solid waste. At the same time, the remaining steam is further generated through the low-temperature steam turbine, thereby realizing multi-stage utilization and efficient conversion of energy.

[0044] Further, the system further includes a second air inlet, a second heat exchanger, a second booster, a solid fuel oxide cell cathode, and a third heat exchanger connected in sequence, the solid fuel oxide cell cathode is connected to the air compressor, and the third heat exchanger is connected to the combustion chamber.

[0045] Based on the above technical scheme, the air compressor stably supplies oxygen to the solid oxide fuel cell cathode, the normal-temperature air is heated through the second heat exchanger, and after being pressurized by the second booster, part of the oxygen enters the solid fuel oxide cell cathode, and the remaining other components enter the combustion chamber after passing through the third heat exchanger, and react with the combustible gas that does not participate in the reaction in the solid fuel oxide cell.

[0046] Further, the system further includes:

[0047] The first inlet, the first supercharger, the first heat exchanger, the first flow divider and the lower column of the rectifying tower are sequentially connected, the first heat exchanger is connected with the pure nitrogen outlet and the waste nitrogen outlet respectively, and the lower column of the rectifying tower is connected with the oxygen-rich liquid air conveying pipe, the pure liquid nitrogen conveying pipe and the nitrogen-rich liquid air conveying pipe respectively.

[0048] The oxygen-rich liquid air conveying pipe, the pure liquid nitrogen conveying pipe and the nitrogen-rich liquid air conveying pipe are all connected with the liquid air supercooler, and the liquid air supercooler is connected with the throttling device and the first pure nitrogen conveying pipe.

[0049] The expander, the second flow divider, the cooling air conveying pipe, the upper column of the rectifying tower and the first pure nitrogen conveying pipe are sequentially connected, and the cooling air conveying pipe is connected with the first heat exchanger.

[0050] Based on the above technical scheme, the clean air is pressurized by the first supercharger and then enters the first heat exchanger, a part of the clean air enters the lower column of the rectifying tower through the first flow divider, and the oxygen-rich liquid air, the nitrogen-rich liquid air and the pure liquid nitrogen are obtained, the oxygen-rich liquid air, the nitrogen-rich liquid air and the pure liquid nitrogen are cooled by heat exchange in the liquid air supercooler after being mixed with the pure nitrogen gas from the upper column of the rectifying tower, and then are throttled by the throttling device and sent to the upper column of the rectifying tower for rectification, after the rectification of the upper column of the rectifying tower, the pure nitrogen gas, the oxygen and the waste nitrogen are obtained, the oxygen is reheated to room temperature by the first heat exchanger and then is led out from the oxygen outlet, the pure nitrogen is reheated to room temperature by the nitrogen gas supercooler and the first heat exchanger and then is led out from the pure nitrogen outlet, another part of the clean air enters the second flow divider after being continuously cooled by the expander, most of the cooling air enters the upper column of the rectifying tower for rectification, and a small part of the cooling air is mixed with the waste nitrogen from the nitrogen gas supercooler and then enters the first heat exchanger to be reheated to room temperature and is led out from the waste nitrogen outlet.

[0051] Further, the upper column of the rectifying tower is connected with the throttling device, the upper column of the rectifying tower is also connected with the nitrogen gas supercooler, the upper column of the rectifying tower is connected with the first heat exchanger through the oxygen conveying pipe, the lower column of the rectifying tower is connected with the first flow divider, and the nitrogen gas supercooler is connected with the first heat exchanger through the waste nitrogen conveying pipe and the second pure nitrogen conveying pipe.

[0052] Based on the above technical scheme, the deep cooling air separation device adopts double-tower rectification of the upper column of the rectifying tower and the lower column of the rectifying tower, and simultaneously obtains the waste nitrogen and the pure nitrogen while preparing the high-purity oxygen for the regenerative reactor of the high-purity oxygen supply system and the solid oxide fuel cell reaction.

[0053] Further, the water pump, the waste heat utilization boiler, the high-pressure steam turbine, the low-pressure steam turbine and the high-temperature water vapor outlet are sequentially connected, and the high-pressure steam turbine is connected with the high-temperature water vapor conveying pipe.

[0054] Based on the above technical solution, after being pressurized by a water pump, it enters the waste heat utilization boiler and is heated to high-temperature steam, which drives the steam turbine to generate electricity. Part of the high-temperature steam at the outlet of the high-pressure steam turbine enters the gasification reactor as a gasification medium for the gasification reaction of biomass, and the remaining part enters the low-temperature steam turbine to further drive the steam turbine to generate electricity. The low-temperature water vapor finally generated can be used for industrial, domestic water or other purposes.

[0055] Furthermore, the high-temperature flue gas conveying pipe is connected to the waste heat utilization boiler through the gas turbine, the flue gas purification system is connected to the waste heat utilization boiler, and the waste heat utilization boiler is connected to the CCS.

[0056] Based on the above technical solution, the high-temperature flue gas generated in the combustion chamber enters the gas turbine after being preheated by the air, and then the exhaust gas is introduced into the waste heat utilization boiler, forming a highly efficient energy utilization system. The high-concentration CO2 flue gas generated by the regeneration reactor passes through the flue gas purification system, enters the waste heat utilization boiler, and finally enters the CCS, thereby improving energy utilization efficiency and reducing greenhouse gas emissions.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] The present invention can overcome the defects of traditional power generation systems: (1) low energy utilization efficiency and difficulty in achieving multi-level utilization; (2) serious environmental pollution and high greenhouse gas emissions.

[0059] The present invention has the following advantages: (1) The system integrates multi-stage energy utilization, has high thermal efficiency, and effectively utilizes waste heat; (2) Through efficient waste gas purification and carbon capture, the unity of hydrogen-rich production and environmental protection goals is achieved; (3) The calcium-based adsorbent can be recycled, thereby improving resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 This is a system diagram of the high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells provided by the present invention. DETAILED DESCRIPTION

[0061] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0062] Example 1

[0063] like Figure 1As shown, the efficient circulating power generation system based on calcium-based chemical looping gasification hydrogen production coupled with solid oxide fuel cell includes a gasification reactor, a third diverter, a first return valve, a regeneration reactor, a fourth heat exchanger, a CO2-rich flue gas delivery pipe, a flue gas purification system, a waste heat utilization boiler, and a carbon capture and storage module, which are sequentially connected. The gasification reactor is connected to the third diverter, and the gasification reactor is also connected to the high-temperature steam delivery pipe. The regeneration reactor is connected to the fourth heat exchanger.

[0064] The municipal solid waste is sent to the gasification reactor at a flow rate of 5000 kg / h, and the operating temperature of the gasification reactor is set to 650℃. At the same time, the temperature of the regeneration reactor is adjusted to 900℃. Then, calcium oxide powder is added to the gasification reactor, and the initial flow rate is set to 1500 kg / h. Water vapor is also added, and the flow rate is set to 1200 kg / h. Under these conditions, the gas composition at the outlet of the gasification reactor is monitored, and it is found that the H2 concentration can reach 92.6%, and the H2 yield is 429 kg / h. In addition, in the regeneration reactor, as the flow rates of calcium oxide and water vapor increase, the CO2 concentration at the outlet of the regeneration reactor can reach 95.15%, and the yield is 4574 kg / h, which optimizes the carbon dioxide capture and conversion capacity of the system. However, it should be noted that when the temperature of the regeneration reactor is too high, it may cause the deactivation of the calcium-based sorbent, thereby reducing its capture capacity, so the temperature of the regeneration reactor should be controlled within the range of 875-1100℃ in actual operation. By reasonably configuring the flow rates of calcium oxide and water vapor, and the temperatures of the gasification reactor and the regeneration reactor, the production of hydrogen in the gasification reactor and carbon dioxide in the regeneration reactor is significantly improved, thereby realizing efficient utilization of resources and environmental protection effect.

[0065] Example 2

[0066] Based on Example 1, as shown in Figure 1 The regeneration reactor is connected to the first return valve, the oxygen outlet, the calcium-based sorbent conveyor, and the fourth heat exchanger. The first return valve is connected to the third diverter, and the oxygen outlet is connected to the first heat exchanger and the air compressor.

[0067] The calcium-based sorbent is based on calcium-based waste calcium carbide slag, and the flow rate is set to 4000 kg / h, and the water vapor flow rate is 6000 kg / h to ensure effective heat transfer and material flow in the reactor. During system operation, CO2 is highly captured by the regeneration reactor, and the carbon loading rate of calcium oxide is calibrated to 0.35 g / g during each cycle. At the same time, the calcium-based sorbent flow rate from the regeneration reactor to the gasification reactor is controlled. By achieving efficient use of calcium-based sorbent and effective treatment of tail gas, the overall efficiency and economy of chemical looping gasification hydrogen production are significantly improved.

[0068] In the gasification reactor, the concentrations of hydrogen, carbon monoxide and methane in the synthesis gas are continuously monitored as the calcium-based sorbent flow changes, to evaluate the hydrogen production effect at different cycle times, ensure that the hydrogen concentration reaches 70%, and the concentrations of carbon monoxide and methane are maintained within the corresponding effective range. In addition, a fourth heat exchanger is provided to exclude the influence of calcium oxide, ash and other materials on the heat balance, thereby maximizing the thermal efficiency.

[0069] The gasification reactor adopts a bubbling fluidized bed coupled with a riser, ensuring that the carbon conversion rate is maintained above 0.8. In the regeneration reactor, the oxygen inlet flow is precisely controlled at 1200 kg / h, and 0.19 of synthesis gas is injected in proportion, so that the system can operate self-heating without additional heat source, while optimizing the concentration of hydrogen in the synthesis gas to 90%. To improve the operating efficiency of the system, the inlet flow of calcium-based sorbent and water vapor is adjusted to 10000 kg / h, and the Ca / C ratio and S / B ratio of the system are increased, so that the hydrogen production rate is significantly increased to 306.57 kg / h, while the CO2 concentration at the outlet of the regeneration reactor reaches 99.33%, and the yield is as high as 2603.67 kg / h. This method effectively realizes a high-efficiency and economical hydrogen production process, while ensuring the stable operation of the system and environmental friendliness. This reflects the innovation and application potential of the present application in the field of calcium-based sorbent chemical looping gasification hydrogen production.

[0070] Example 3

[0071] Based on the above embodiments, as shown in Figure 1 The system further comprises:

[0072] The purification system, the hydrogen-rich synthesis gas delivery pipe, the solid oxide fuel cell anode, the fourth flow divider, the combustion chamber and the high-temperature flue gas delivery pipe are sequentially connected, and the solid oxide fuel cell anode is connected to the solid oxide fuel cell cathode and the fourth flow divider;

[0073] The second inlet, the second heat exchanger, the second booster, the solid fuel oxide cell cathode and the third heat exchanger are sequentially connected, the solid fuel oxide cell cathode is connected to the air compressor, and the third heat exchanger is connected to the combustion chamber.

[0074] The hydrogen-rich synthesis gas enters the anode of the solid oxide fuel cell and is mixed with the split-off water vapor generated by the anode of the solid oxide fuel cell, so as to further increase the hydrogen concentration in the synthesis gas to 70% and the yield, and then the hydrogen-rich synthesis gas is subjected to an oxidation reaction with the oxygen from the cathode of the solid oxide fuel cell. The oxygen flow is accurately controlled to be 1200 kg / h. The high-temperature water vapor generated by the anode of the solid oxide fuel cell and other synthesis gas components (such as CO, CH4, etc.) that do not participate in the reaction enter the combustion chamber after passing through the fourth splitter. The air at normal temperature from the second air inlet enters the cathode of the solid oxide fuel cell after passing through the second heat exchanger and the second booster, part of the oxygen enters the anode of the solid oxide fuel cell, and the remaining other components enter the combustion chamber after passing through the third heat exchanger and are subjected to a combustion reaction with the combustible gas that does not participate in the reaction in the anode of the solid oxide fuel cell. The high-temperature flue gas generated in the combustion chamber enters the gas turbine after being preheated with air, forming a cogeneration power generation mode. By increasing the operating temperature to 800-900°C and the operating pressure to 3 bar, the power generation capacity of the SOFC reaches 9.3 MW, and the efficiency reaches 57%, reaching the best state.

[0075] In the implementation process, in order to avoid the generation of a large amount of nitrogen in the exhaust gas of the combustion chamber, pure oxygen is selected as the oxidant of the cathode of the solid oxide fuel cell, so that the main components of the exhaust gas generated thereby are CO2 and water vapor, which is beneficial to the subsequent capture and storage of CO2. In this case, reasonable control of the mixing ratio of oxygen in the anode inlet gas of the solid oxide fuel cell to the flue gas to 40% can effectively improve the power generation efficiency of the solid oxide fuel cell and reduce the risk of local overheating.

[0076] With the increase of the oxygen content, the power generation capacity and the power generation efficiency of the anode of the solid oxide fuel cell continue to increase, while the proportion of water vapor in the flue gas of the combustion chamber is maintained at 51.63%, and the proportion of CO2 is 40.54%. The CO2 concentration in the treated flue gas can reach 83.81%, which effectively improves the performance of the solid oxide fuel cell, reduces the CO2 emission, and improves the overall thermal efficiency and environmental friendliness of the system.

[0077] Example 4

[0078] On the basis of the above-mentioned embodiments, as shown in Figure 1 the system further comprises:

[0079] The first air inlet, the first booster, the first heat exchanger, the first splitter and the lower tower of the rectifying tower are sequentially connected, the first heat exchanger is connected with the waste nitrogen outlet and the pure nitrogen outlet respectively, and the lower tower of the rectifying tower is connected with the oxygen-rich liquid air conveying pipe, the pure liquid nitrogen conveying pipe and the nitrogen-rich liquid air conveying pipe respectively;

[0080] The oxygen-rich liquid air conveying pipe, the pure liquid nitrogen conveying pipe and the nitrogen-rich liquid air conveying pipe are all communicated with a liquid air subcooler, the liquid air subcooler is communicated with a throttler and a first pure nitrogen conveying pipe;

[0081] The expander, the second flow divider, the cooling air conveying pipe, the upper rectification tower and the first pure nitrogen conveying pipe are sequentially communicated, and the cooling air conveying pipe is communicated with the first heat exchanger;

[0082] The upper rectification tower is communicated with the throttler, and the upper rectification tower is further communicated with a nitrogen gas subcooler, the upper rectification tower is communicated with the first heat exchanger through an oxygen conveying pipe, the lower rectification tower is communicated with the first flow divider, and the nitrogen gas subcooler is communicated with the first heat exchanger through a dirty nitrogen conveying pipe and a second pure nitrogen conveying pipe.

[0083] The first inlet air flow is 2500 kg / h, which is composed of nitrogen and oxygen. The clean air is first pressurized to 3 bar and then enters the first heat exchanger for heat exchange, and then is cooled to 282 K and then is divided by the first flow divider, a part of which enters the lower rectification tower for separation to obtain oxygen-rich liquid air, nitrogen-rich liquid air and pure liquid nitrogen. The oxygen-rich liquid is cooled and exchanged in the liquid air subcooler, and then is conveyed to the upper part of the rectification tower to participate in the separation and purification of oxygen, and the nitrogen-rich liquid air and the pure liquid nitrogen are cooled and exchanged with the pure nitrogen gas from the upper rectification tower in the liquid air subcooler, and then are throttled by the throttler and sent to the upper rectification tower for rectification, wherein the liquid nitrogen is sent to the top of the upper rectification tower as the reflux liquid of the upper rectification tower, and the other part of the clean air enters the expander for further cooling (96 K, 1.41 bar) and then enters the second flow divider, 95% of the cooled air enters the upper rectification tower for rectification to obtain pure nitrogen, oxygen and dirty nitrogen, wherein the oxygen is heated to normal temperature after the first heat exchanger and is then led out, the pure nitrogen is heated to normal temperature after the nitrogen gas subcooler and the first heat exchanger and is then led out, and the dirty nitrogen from the upper rectification tower is mixed with 5% of the cooled air after the second flow divider, and then enters the first heat exchanger to be heated to normal temperature and is then led out.

[0084] The deep cooling air separation device adopts a double-tower rectification configuration, wherein the lower rectification tower is not provided with a tower bottom reboiler, and the upper rectification tower is not provided with a tower top condenser, so as to simplify the design and calculation. Through heat exchange, the absolute values of the heat loads of the upper rectification tower and the lower rectification tower are close, so that the effect of heat recovery and utilization is achieved, and only 0.012 MW is required to realize the heat balance between the two towers, which shows the advantage of low energy consumption of the air separation system. Further calculation shows that when the inlet air flow is 25000 kg / h, the purity of the outlet oxygen of the system reaches 99.52%, the yield is 5541.091 kg / h, and the total energy consumption is 4.177 MW.

[0085] Example 5

[0086] Based on the above embodiments, Figure 1 As shown, the system further includes: a water pump, a waste heat utilization boiler, a high-pressure steam turbine, a low-pressure steam turbine and a high-temperature steam outlet are sequentially connected, and the high-pressure steam turbine is connected to the high-temperature steam delivery pipe;

[0087] The high-temperature flue gas conveying pipe is connected to the waste heat utilization boiler through the gas turbine, the flue gas purification system is connected to the waste heat utilization boiler, and the waste heat utilization boiler is connected to the CCS.

[0088] The pump requires 174.34kW of shaft power. The boiler feedwater is pressurized by the pump and then flows into the waste heat recovery boiler. From there, it enters the high-pressure steam turbine. A portion of the high-temperature steam from the high-pressure steam turbine enters the gasification reactor in the calcium-based adsorbent chemical looping gasification hydrogen production unit, while the remainder enters the low-pressure steam turbine. The high-temperature steam from the low-pressure steam turbine can be used for industrial and domestic purposes. The high-temperature flue gas enters the gas turbine, and the exhaust temperature of the gas turbine is higher than 538°C. The pressure of the high-pressure steam turbine is set to 6MPa. The temperature of the high-pressure steam turbine is 20-40°C lower than the exhaust temperature of the gas turbine, and is selected to be 540°C. The pressure of the low-pressure steam turbine is 0.72MPa, and the temperature of the low-pressure steam turbine is 270°C. Then the high-temperature flue gas and the CO2-rich flue gas generated by the regeneration reactor enter the waste heat utilization boiler. The temperature difference between the high-pressure and low-pressure feed water nodes of the waste heat utilization boiler is set to 12°C, the approach point temperature difference is set to 15°C, and the feed water temperature is 20°C. The waste heat in the high-temperature flue gas is recovered and converted into high-temperature steam. The high-temperature steam drives the steam turbine to generate electricity. The remaining part is used as a gasification medium in the gasification reactor to promote the gasification reaction of solid waste. At the same time, the remaining steam is further used to generate electricity through the low-temperature steam turbine, thereby realizing multi-stage utilization and efficient conversion of energy, and finally enters the CCS module, improving energy utilization efficiency and reducing greenhouse gas emissions.

[0089] The steam system generates 6.326 MW of power. The high-temperature steam entering the gasification reactor has a flow rate of 44,500 kg / h and a temperature of 430.27°C. The high-temperature steam exiting the low-pressure steam turbine has a flow rate of 45,500 kg / h and a temperature of 80°C. The high-pressure steam turbine inlet temperature is 540°C, generating 2.255 MW of power. The low-pressure steam turbine inlet temperature is 270°C, generating 4.245 MW of power.

[0090] Example 6

[0091] The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification for hydrogen production coupled with solid oxide fuel cells in the above-mentioned embodiments is used to perform high-efficiency cycle power generation based on calcium-based chemical chaining gasification for hydrogen production coupled with solid oxide fuel cells:

[0092] The biomass enters a gasification reactor, and after pyrolysis, gasification and reforming in the gasification reactor, a hydrogen-rich synthesis gas is formed after passing through a third flow divider and a purification system;

[0093] The calcium-based sorbent enters a regeneration reactor for calcination and regeneration, and after passing through a fourth heat exchanger and a second return valve, enters the gasification reactor to promote the high-temperature steam reforming reaction of the biomass and the catalytic cracking of tar, and release heat, and after capturing CO2, together with residual coke particles, passes through the third flow divider and the first return valve into the regeneration reactor for regeneration and release of the CO2 molecules carried by itself;

[0094] The CO2-rich flue gas generated in the regeneration reactor passes through a flue gas purification system, enters a waste heat utilization boiler, and finally enters CCS;

[0095] Clean air enters a first heat exchanger through a booster, and then is divided into a lower column of a rectifying column and an upper column of the rectifying column, forming nitrogen, dirty nitrogen and high-purity oxygen, part of which is used for combustion of coke in the regeneration reactor, and the other part enters the cathode of a solid oxide fuel cell through an air compressor;

[0096] The hydrogen-rich synthesis gas passes through the anode of the solid oxide fuel cell, and the solid oxide fuel cell converts chemical energy into electrical energy, and the unreacted hydrogen and other synthesis gas components enter a combustion chamber for combustion and energy release, and the generated high-temperature flue gas enters a waste heat boiler through a gas turbine;

[0097] Water pumped by a water pump is heated to high-temperature steam after passing through the waste heat utilization boiler, and drives a steam turbine to generate electricity, and the outlet high-temperature steam enters the gasification reactor as a gasification medium for the gasification reaction of solid waste, and the remaining part enters a low-temperature steam turbine to further drive the steam turbine to generate electricity.

[0098] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells, characterized in that: It at least includes a gasification reactor, a third diverter, a first return valve, a regeneration reactor, a fourth heat exchanger, a CO2-rich flue gas conveying pipe, a flue gas purification system, a waste heat utilization boiler, and a carbon capture and storage module, which are connected in sequence. The gasification reactor is connected to the third diverter, and the gasification reactor is also connected to the high-temperature steam conveying pipe, and the regeneration reactor is connected to the fourth heat exchanger. The system for generating electricity comprises at least the following steps: The biomass enters the gasification reactor, where it undergoes pyrolysis, gasification, and reforming, and then passes through the third splitter and purification system to form hydrogen-rich synthesis gas; The calcium-based adsorbent enters the regeneration reactor for calcination regeneration, passes through the fourth heat exchanger and the second return valve into the gasification reactor, promotes the high-temperature steam reforming reaction of biomass and the catalytic cracking of tar, and releases heat. After capturing CO2, it enters the regeneration reactor together with the residual coke particles through the third diverter and the first return valve for regeneration, and releases the CO2 molecules it carries. The CO2-rich flue gas generated by the regeneration reactor passes through the flue gas purification system, enters the waste heat utilization boiler, and finally enters the CCS; The clean air passes through the supercharger and enters the first heat exchanger. It is then split and flows into the lower and upper towers of the distillation tower to generate nitrogen, polluted nitrogen, and high-purity oxygen. Part of the oxygen is used to burn the coke in the regeneration reactor, and the rest enters the cathode of the solid oxide fuel cell through the air compressor. The hydrogen-rich syngas passes through the anode of the solid oxide fuel cell, which converts chemical energy into electrical energy. The unreacted hydrogen and other syngas components enter the combustion chamber for combustion and release energy. The generated high-temperature flue gas enters the waste heat boiler through the gas turbine; After the water pump feed water passes through the waste heat utilization boiler, it is heated to high-temperature steam, which drives the steam turbine to generate electricity. Part of the high-temperature steam at the outlet enters the gasification reactor as a gasification medium for the gasification reaction of solid waste, and the remaining part enters the low-temperature steam turbine to further drive the steam turbine to generate electricity.

2. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells according to claim 1 is characterized by: The regeneration reactor is connected to the first return valve, the oxygen outlet, the calcium-based adsorbent conveyor and the fourth heat exchanger. The first return valve is connected to the third diverter. The oxygen outlet is connected to the first heat exchanger and the air compressor.

3. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells according to claim 1 is characterized by: The system also includes a purification system, a hydrogen-rich synthesis gas conveying pipe, a solid oxide fuel cell anode, a fourth diverter, a combustion chamber and a high-temperature flue gas conveying pipe connected in sequence, and the solid oxide fuel cell anode is connected to the solid oxide fuel cell cathode and the fourth diverter.

4. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells according to claim 1 is characterized by: The system further includes a second air inlet, a second heat exchanger, a second supercharger, the solid fuel oxide cell cathode and a third heat exchanger which are connected in sequence. The solid fuel oxide cell cathode is connected to the air compressor, and the third heat exchanger is connected to the combustion chamber.

5. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells according to claim 1 is characterized in that: The system further comprises: The first air inlet, the first supercharger, the first heat exchanger, the first splitter and the lower tower of the distillation tower are connected in sequence, the first heat exchanger is connected to the dirty nitrogen outlet and the pure nitrogen outlet respectively, and the lower tower of the distillation tower is connected to the oxygen-enriched liquid air delivery pipe, the pure liquid nitrogen delivery pipe and the nitrogen-enriched liquid air delivery pipe respectively; The oxygen-enriched liquid air delivery pipe, the pure liquid nitrogen delivery pipe, and the nitrogen-enriched liquid air delivery pipe are all connected to a liquid-to-air subcooler, and the liquid-to-air subcooler is connected to a throttle and a first pure nitrogen delivery pipe; The expander, the second splitter, the cooling air delivery pipe, the upper tower of the distillation tower and the first pure nitrogen delivery pipe are connected in sequence, and the cooling air delivery pipe is connected to the first heat exchanger.

6. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification and hydrogen production coupled with solid oxide fuel cells according to claim 1 is characterized by: The upper tower of the distillation tower is connected to the throttle, and the upper tower of the distillation tower is also connected to the nitrogen subcooler. The upper tower of the distillation tower is connected to the first heat exchanger through an oxygen delivery pipe, and the lower tower of the distillation tower is connected to the first splitter. The nitrogen subcooler is connected to the first heat exchanger through a dirty nitrogen delivery pipe and a second pure nitrogen delivery pipe respectively.

7. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification hydrogen production coupled with solid oxide fuel cells according to claim 1 is characterized by: The water pump, the waste heat utilization boiler, the high-pressure steam turbine, the low-pressure steam turbine and the high-temperature steam outlet are connected in sequence, and the high-pressure steam turbine is connected to the high-temperature steam delivery pipe.

8. The high-efficiency cycle power generation system based on calcium-based chemical chaining gasification and hydrogen production coupled with a solid oxide fuel cell according to any one of claims 1 to 7, characterized in that: The high-temperature flue gas conveying pipe is connected to the waste heat utilization boiler through the gas turbine, the flue gas purification system is connected to the waste heat utilization boiler, and the waste heat utilization boiler is connected to the CCS.

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