CN116435541A - A negative carbon emission power generation system and method based on efficient utilization of biomass - Google Patents

Abstract

The invention discloses a negative carbon emission power generation system and method based on high-efficiency utilization of biomass. The system includes a biomass gasification device, a solid oxide fuel cell and a solid oxide electrolytic cell; the anode electrolysis product of the solid oxide electrolytic cell It is divided into three parts, which are respectively used as biomass gasification raw material, oxidant and oxygen storage; after the anode product of the solid oxide fuel cell and the oxidant are burned to do work, one part is provided to the biomass gasification device as raw material, and the other part is provided to the solid The oxide electrolytic cell is used as the raw material for electrolysis; the present invention adopts the coordinated control of the BG-SOFC power generation system and the SOEC co-electrolysis system. In addition to realizing high-efficiency power generation, the system can also control CO ₂ and H ₂ O in the flue gas as well as the The energy is fully recovered, thereby realizing the negative carbon emission of the entire system.

Description

A negative carbon emission power generation system and method based on efficient utilization of biomass

technical field

The invention relates to the technical field of biomass power generation, in particular to a negative carbon emission power generation system and method based on efficient utilization of biomass.

Background technique

Global warming and energy crisis have brought great challenges to human survival and development. The emission of a large amount of greenhouse gases, especially carbon dioxide, has sharply aggravated the greenhouse effect. Reducing carbon emissions during power generation, improving energy conversion efficiency, and efficient use of renewable energy are considered to be effective means to solve this problem. Compared with renewable energy such as solar energy and wind energy, biomass energy has the advantage of continuous power generation. Compared with traditional biomass efficient utilization methods such as combustion, fermentation, and pyrolysis, gasification has the advantages of low pollutant emissions, large volume of syngas, and high conversion efficiency, and has attracted extensive attention from researchers all over the world. In the biomass gas utilization scenario, compared with other prime movers, solid oxide fuel cells exhibit high power generation efficiency and low pollution. In addition, the solid oxide electrolysis cell also has the characteristics of strong fuel adaptability and high electrolysis efficiency, which provides the possibility to achieve high-efficiency carbon capture.

The inventors found that in the existing solid oxide fuel cell/solid oxide electrolytic cell/biomass gasification technology integration scheme, the power generation efficiency of the system needs to be improved due to the high energy consumption of the solid oxide electrolytic cell. The concentration of carbon dioxide in flue gas is low, and the energy consumption required for capture is high, but most of the existing technologies do not capture carbon dioxide.

Contents of the invention

Aiming at the problems existing in the prior art, the present invention provides a negative carbon emission power generation system and method based on efficient utilization of biomass to solve the problems of low power generation efficiency and high energy consumption of carbon dioxide capture in existing biomass power generation systems.

Technical scheme of the present invention is as follows:

In the first aspect of the present invention, a negative carbon emission power generation system based on efficient utilization of biomass, including a biomass gasification device, a solid oxide fuel cell and a solid oxide electrolytic cell;

Wherein, the biomass gasification device provides the anode raw material for the solid oxide fuel cell, and the cathode electrolysis product of the solid oxide electrolytic cell is used as a supplement for the anode raw material of the solid oxide fuel cell;

The anode electrolysis product of the solid oxide electrolytic cell is divided into three parts, which are respectively used as biomass gasification raw material, oxidant and oxygen storage; after the anode product of the solid oxide fuel cell and the oxidant are burned to do work, a part is provided for biomass gasification The device is used as raw material, and the other part is provided to the solid oxide electrolytic cell as electrolytic raw material.

In some embodiments of the present invention, the raw material inlet of the biomass gasification device is connected to the first splitter, the second splitter and the biomass source respectively, and the syngas outlet of the biomass gasification device is connected to the second air heater, synthesis compressor and first mixer.

In some embodiments of the present invention, the water source is connected to the first mixer sequentially through the water pump, the water heater, and the second mixer, and the outlet of the first mixer is connected to the anode raw material inlet of the solid oxide fuel cell.

In some embodiments of the present invention, the inlet of the second mixer is also connected with the cathode product outlet of the solid oxide electrolytic cell.

In some embodiments of the present invention, the air is connected to the cathode raw material inlet of the solid oxide fuel cell through the air compressor, the first air heater, the second air heater, and the third air heater.

In some embodiments of the present invention, the cathode product outlet of the solid oxide fuel cell is sequentially connected to an air turbine, a first air heater, and a water heater.

In some embodiments of the present invention, the anode product outlet of the solid oxide fuel cell is sequentially connected to the combustion chamber, the gas turbine, and the first splitter, one outlet of the first splitter is connected to the biomass gasification device, and the other One outlet is connected with the raw material inlet of the solid oxide electrolytic cell through the third air heater.

In some embodiments of the present invention, the anode electrolysis product outlet of the solid oxide electrolytic cell is connected to the second flow divider, and the second flow divider is provided with three outlets, which are respectively connected to the biomass gasification device and the combustion chamber , Oxygen storage device.

In some embodiments of the present invention, the solid oxide electrolysis cell is powered by a solid oxide fuel cell.

In the second aspect of the present invention, a method for generating electricity with negative carbon emissions based on efficient use of biomass is provided, including: while the solid oxide fuel cell generates electricity to provide electricity, part of the high-temperature flue gas generated by itself is gasified by biomass The other part of the flue gas is used as high-temperature raw material for the solid oxide electrolytic cell; at the same time, the solid oxide electrolytic cell supplies the electrolysis product to the solid oxide fuel cell, and the cathode electrolysis product is used as a supplement for the electrochemical reaction of the solid oxide fuel cell Raw materials, anode electrolysis products are used as raw materials for solid oxide fuel cell oxygen-rich combustion and biomass gasification.

One or more technical solutions of the present invention have the following beneficial effects:

The system provided by the invention highly integrates a biomass gasification-solid oxide fuel cell (BG-SOFC) power generation system and a solid oxide electrolytic cell (SOEC) co-electrolysis system based on the principle of energy cascade utilization. While the BG-SOFC power generation system provides electricity, part of the high-temperature flue gas (CO ₂ +H ₂ O) generated by itself is recovered through the gasification device, and the other part of the flue gas is used as high-temperature raw material for the SOEC co-electrolysis system; at the same time, the SOEC co-electrolysis system The electrolysis system supplies the electrolysis products (mainly including CO+H ₂ +O ₂ ) to the BG-SOFC power generation system, in which CO+H ₂ is used as the supplementary raw material for the electrochemical reaction of SOFC, and O ₂ is used as the oxygen-enriched combustion and biomass of the BG-SOFC power generation system Gasified raw materials. Through the coordinated control of the BG-SOFC power generation system and the SOEC co-electrolysis system, the system can not only achieve high-efficiency power generation, but also fully recover CO ₂ +H ₂ O and the energy contained in the flue gas, thereby realizing the energy efficiency of the entire system. Negative carbon emissions. The system and the improved model based on it can play an important role in the field of biomass power generation.

The system of the present invention can convert the cathode product and anode product of the solid oxide fuel cell into mechanical work through the provided air turbine and gas turbine, and realize the solid oxide fuel cell through the provided multiple air heaters and water heaters. The thermal energy of the cathode product and the anode product is recycled; the electric energy of the solid oxide electrolytic cell comes from the solid oxide fuel cell, and there is no need to provide additional electric energy; the system can realize the full recovery and utilization of various energies in the system, ensuring high Efficient power generation while achieving negative carbon emissions for the entire system.

Description of drawings

Figure 1 is a schematic diagram of a negative carbon emission power generation system based on efficient utilization of biomass.

Among them, 1. Biomass; 2. The first part of high-temperature flue gas; 3. Syngas; 4. Low-temperature synthesis gas; 5. High-temperature and high-pressure synthesis gas; 6. Anode raw materials; 7. Anode products; 8. Combustion products; 9. The gas after the second work; 10. The second part of high-temperature flue gas; 11. The raw material for electrolysis; 12. The cathode electrolysis product; 13. The anode electrolysis product; 14. The first part of oxygen; 15. The second part of oxygen; 16. The third part Oxygen; 17. Air; 18. Compressed air; 19. Primary heating air; 20. Secondary heating air; 21. Cathode raw material; 22. Cathode product; 23. Gas after the first work; 24. Primary cooling gas; 25. Secondary cooling gas; 26. Water source; 27. Pressurized water; 28. Water vapor; 29. Mixed gas;

AB is the combustion chamber; AC is the air compressor; AH1 is the first air heater; AH2 is the second air heater; AH3 is the third air heater; WP is the water pump; WH is the water heater; M1 is the first mixing M2 is the second mixer; SC is the syngas compressor; SOFC is the solid oxide fuel cell; T1 is the air turbine; T2 is the gas turbine; SP1 is the first splitter; SP2 is the second splitter; Material gasification device; SOEC is solid oxide electrolytic cell; OSU is oxygen storage device; Inv is inverter.

Detailed ways

Example 1

In a typical implementation of the present invention, as shown in Figure 1, a negative carbon emission power generation system based on efficient utilization of biomass is proposed, including biomass gasification device GAS, solid oxide fuel cell SOFC and solid oxide electrolysis Pond SOEC, wherein, the biomass gasification device GAS provides anode raw material for solid oxide fuel cell SOFC, and the cathode electrolysis product of the solid oxide electrolytic cell SOEC is used as a supplement for the solid oxide fuel cell SOFC anode raw material; The anode electrolysis product of the solid oxide fuel cell SOEC is divided into three parts, which are respectively used as biomass gasification raw materials, oxidant and oxygen storage; after the anode product of the solid oxide fuel cell SOFC and the oxidant are burned to do work, a part is provided for biomass gasification The device is used as raw material, and the other part is provided to the solid oxide electrolytic cell as electrolytic raw material.

Specifically, the biomass gasification device GAS is a process of converting solid biomass into gaseous fuel by using thermochemical reactions. The substance 1 is connected, and the outlet of the synthesis gas 3 of the biomass gasification device GAS is connected to the second air heater AH2, the synthesis compressor SC and the first mixer M1 in sequence.

Solid Oxide Fuel Cell (SOFC) is a high-temperature fuel cell that uses hydrocarbons as its fuel for power generation, and converts the chemical energy of the fuel into electrical energy to achieve power generation. The water source 26 is connected to the first mixer M1 sequentially through the water pump WP, the water heater WH, and the second mixer M2, and the outlet of the first mixer M1 is connected to the anode raw material inlet of the solid oxide fuel cell SOFC; The inlet of the second mixer M2 is also connected with the cathode product outlet of the solid oxide electrolytic cell SOEC. The air 17 is connected to the cathode raw material inlet of the solid oxide fuel cell SOFC through the air compressor AC, the first air heater AH1, the second air heater AH2, and the third air heater AH3. The cathode product outlet of the solid oxide fuel cell SOFC is sequentially connected to the air turbine T1, the first air heater AH1, and the water heater WH. The anode product outlet of the solid oxide fuel cell SOFC is sequentially connected to the combustion chamber AB, the gas turbine T2, and the first splitter SP1, one outlet of the first splitter SP1 is connected to the biomass gasification device GAS, and the other outlet passes through The third air heater AH3 is connected with the raw material inlet of the solid oxide electrolytic cell SOEC.

The solid oxide electrolytic cell SOEC is a solid oxide fuel cell that operates in reverse. It performs an electrolytic reaction at an applied voltage and high temperature to convert electrical energy and thermal energy into chemical energy. The anode electrolysis product outlet of the solid oxide electrolytic cell SOEC is It is connected with the second splitter SP2, and the second splitter SP2 is provided with three outlets, respectively connected to the biomass gasification device GAS, the combustion chamber AB, and the oxygen storage device OSU.

In this embodiment, the power of the solid oxide electrolytic cell SOEC is provided by a solid oxide fuel cell SOFC, and the solid oxide fuel cell SOFC is also connected to the inverter Inv to realize the application of electric energy.

The working principle of the negative carbon emission power generation system based on efficient utilization of biomass provided in this example is as follows:

Biomass 1 and the first part of high-temperature flue gas 2 containing H ₂ O and CO ₂ from the first splitter SP1 and the third part of oxygen 16 from the second splitter SP2 undergo gasification reaction in the biomass gasification device GAS, Synthesis gas 3 is generated; then the synthesis gas 3 passes through the second air heater AH2 to heat the primary heated air 19 from the first air heater AH1, the temperature of the synthesis gas decreases, and becomes a low-temperature synthesis gas 4, which is then compressed by the synthesis gas The machine SC compresses and sends to the first mixer M1; at the same time, the external water source 26 is pressurized by the water pump WP to become pressurized water 27, and is heated by the water heater WH to become water vapor 28, which is sent to the second mixer M2. In the second mixer M2, it is mixed with the cathodic electrolysis product 12 (mainly containing CO and H ₂ ) from the solid oxide electrolysis cell SOEC; then the mixed gas 29 is mixed with the high-temperature and high-pressure synthesis gas 5 in the first mixer M1, As SOFC anode raw material 6.

The air 17 in the atmosphere is compressed by the air compressor AC, heated by the first air heater AH1, the second air heater AH2, and the third air heater AH3 in sequence, and then sent to the solid oxide fuel cell SOFC as the cathode raw material 21 Cathode; then, the cathode raw material 21 and the anode raw material 6 undergo an electrochemical reaction in the solid oxide fuel cell SOFC to generate electric energy, and then the direct current is converted into alternating current by the inverter Inv.

After the cathode product 22 pushes the air turbine T1 to do work, that is, the gas 23 after the first work, passes through the first air heater AH1 and the water heater WH to release heat to the outside, and finally is discharged to the atmosphere; the anode product 7 and the gas from the second shunt The first part of oxygen 14 of SP2 is stoichiometrically burned in the combustion chamber AB (CO ₂ and H ₂ O are enriched); the combustion product 8 is sent to the first split after the gas turbine T2 does work, that is, the gas 9 after the second work The device SP1 is divided into two parts, wherein the first part of high-temperature flue gas 2 is directly sent to the biogasification device as a gasification agent (without providing additional heat), and the second part of high-temperature flue gas 10 is released by the third air heater AH3 The heat is sent to the solid oxide electrolytic cell SOEC as the electrolysis raw material 11 (without providing additional heat).

The power of the solid oxide electrolysis cell SOEC is provided by the solid oxide fuel cell SOFC, and the electrolysis raw material 11 comes from the third air heater AH3; the anode electrolysis product 13 (O ₂ ) is divided into three parts, and the first part of oxygen 14 is used as solid oxide fuel The oxidant for the combustion of the SOFC anode product of the battery, the second part of oxygen 15 is stored in the oxygen storage device OSU, the third part of oxygen 16 is used as part of the gasification agent of the biomass gasification device GAS; the cathode electrolysis product 12 is sent to The second mixer M2 is used as the anode supplementary raw material of the solid oxide fuel cell SOFC.

Example 2

In a typical implementation of the present invention, a method for generating electricity with negative carbon emissions based on efficient use of biomass is proposed, including: while the solid oxide fuel cell generates electricity to provide electricity, part of the high-temperature flue gas generated by itself passes through the biomass The gasification device recovers, and the other part of the flue gas is used as the high-temperature raw material of the solid oxide electrolytic cell; at the same time, the solid oxide electrolytic cell supplies the electrolysis product to the solid oxide fuel cell, and the cathode electrolysis product is used as the electrochemical fuel cell of the solid oxide fuel cell. The reaction supplements the raw material, and the anode electrolysis product is used as the raw material for the oxygen-rich combustion and biomass gasification of the solid oxide fuel cell.

The embodiments described above have described the technical solutions of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. All done within the principle scope of the present invention Any modification, supplement or substitution in a similar manner shall be included within the protection scope of the present invention.

Claims (10)

1. A negative carbon emission power generation system based on efficient utilization of biomass, characterized in that it includes a biomass gasification device, a solid oxide fuel cell and a solid oxide electrolytic cell; Wherein, the biomass gasification device provides the anode raw material for the solid oxide fuel cell, and the cathode electrolysis product of the solid oxide electrolytic cell is used as a supplement for the anode raw material of the solid oxide fuel cell; The anode electrolysis product of the solid oxide electrolytic cell is divided into three parts, which are respectively used as biomass gasification raw material, oxidant and oxygen storage; after the anode product of the solid oxide fuel cell and the oxidant are burned to do work, a part is provided for biomass gasification The device is used as raw material, and the other part is provided to the solid oxide electrolytic cell as electrolytic raw material. 2. The negative carbon emission power generation system based on efficient utilization of biomass as claimed in claim 1, wherein the raw material inlet of the biomass gasification device is connected to the first splitter, the second splitter and the biomass source respectively , the synthesis gas outlet of the biomass gasification device is sequentially connected to the second air heater, the synthesis compressor and the first mixer. 3. The negative carbon emission power generation system based on high-efficiency utilization of biomass as claimed in claim 2, wherein the water source is connected to the first mixer through a water pump, a water heater, and a second mixer in sequence, and the first mixer The outlet of the solid oxide fuel cell is connected with the anode raw material inlet. 4. The negative carbon emission power generation system based on efficient utilization of biomass as claimed in claim 2, wherein the inlet of the second mixer is also connected to the outlet of the cathode product of the solid oxide electrolytic cell. 5. The negative carbon emission power generation system based on efficient utilization of biomass as claimed in claim 1, wherein the air passes through the air compressor, the first air heater, the second air heater, the third air heater and solid oxidation The cathode raw material inlet of the biofuel cell is connected. 6. The negative carbon emission power generation system based on efficient utilization of biomass according to claim 1, wherein the cathode product outlet of the solid oxide fuel cell is sequentially connected to an air turbine, a first air heater, and a water heater. 7. The negative carbon emission power generation system based on efficient utilization of biomass as claimed in claim 1, wherein the anode product outlet of the solid oxide fuel cell is sequentially connected to the combustion chamber, the gas turbine, and the first flow splitter, and the second One outlet of a splitter is connected with the biomass gasification device, and the other outlet is connected with the raw material inlet of the solid oxide electrolytic cell through the third air heater. 8. The negative carbon emission power generation system based on high-efficiency utilization of biomass as claimed in claim 1, wherein the anode electrolysis product outlet of the solid oxide electrolytic cell is connected to a second shunt, and on the second shunt Three outlets are provided to connect the biomass gasification device, the combustion chamber and the oxygen storage device respectively. 9. The negative carbon emission power generation system based on efficient utilization of biomass as claimed in claim 1, wherein the power of the solid oxide electrolytic cell is provided by a solid oxide fuel cell. 10. A method for generating electricity with negative carbon emissions based on high-efficiency use of biomass, which is realized by using the power generation system described in any one of claims 1-9, characterized in that it includes: while the solid oxide fuel cell generates electricity and provides electricity, Part of the high-temperature flue gas generated by itself is recovered through the biomass gasification device, and the other part of the flue gas is used as high-temperature raw material for the solid oxide electrolytic cell; at the same time, the solid oxide electrolytic cell supplies the electrolysis product to the solid oxide fuel cell, in which the cathode The electrolysis product is used as a supplementary raw material for the electrochemical reaction of the solid oxide fuel cell, and the anode electrolysis product is used as the raw material for the oxygen-enriched combustion and biomass gasification of the solid oxide fuel cell.

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