Wind-light-electricity-heat coupled biomass carbon-alcohol poly-generation method and system

Abstract

The invention relates to a wind-light-electric-heat coupled biomass carbon-alcohol poly-generation method and system, which are suitable for the green energy industry. The system comprises a biomass dry distillation carbon gas co-production device, a pyrolysis gas electrothermal conversion furnace, a waste heat boiler, a boiler feed water preheater, a crude synthesis gas purification system, a synthesis gas compressor unit, a methanol synthesis system, a methanol gas-liquid separator and a green crude methanol storage tank. The wind, light and electric heat can increase the yield of biological green methanol by 80-90%, compared with hydrogen production through water electrolysis, the yield of green methanol converted from carbon monoxide in gasified gas is increased through hydrogenation, and power consumption can be saved by 20% when the yield of green methanol is increased equally; in addition, compared with water electrolysis hydrogen production, the direct wind-solar electric heating requires less than one twentieth of electric heating process investment, equipment maintenance is simple, and the requirement of the highest safety protection level of water electrolysis hydrogen production is avoided. Under the condition of power shortage of green electric power, normal production can still be achieved, and only energy of green methanol capable of increasing yield through electric heating is converted into heating power to be consumed.

Description

Technical Field

[0001] The present invention relates to a wind, photovoltaic, thermal and biomass carbon alcohol cogeneration method and system, which is applicable to the green energy industry. Background Art

[0002] The "dual carbon" economy has developed to its current level. The development of wind and solar power has evolved from grid-connected power generation, to energy storage to regulate wind and solar fluctuations, and then to water electrolysis to produce hydrogen for energy storage; and then turned to green ammonia and green methanol. Green ammonia has many defects, so people have focused the mainstream development direction of green energy on green methanol.

[0003] To produce green methanol, it is not enough to simply generate green hydrogen from wind and solar power. Green carbon sources and green hydrogen synthesis are also needed to produce green methanol. Green carbon dioxide is scarce in places where green electricity is abundant and cheap; the most economical source of green carbon dioxide is biomass, but green electricity is scarce or too expensive in places where biomass is abundant. This raises the question of how to transport cheap green electricity from the north to the south and how to transport abundant green carbon sources from the south to the north. Using ultra-high voltage to transmit electricity not only requires huge investment in infrastructure, but also has a long construction period and high maintenance costs; the transportation of biomass from the south to the north increases the realization cost of the entire industrial chain, and the energy consumption of long-distance transportation will actually greatly reduce the carbon reduction benefits.

[0004] Obviously, the most realistic breakthrough to solve this problem is to deeply study the characteristics of biomass, and fully decompose the solid sunlight - biochar, liquid sunlight - biological green methanol, gaseous sunlight - green steam and green carbon dioxide contained in biomass, so as to maximize the dual benefits of green energy economy and carbon reduction. Summary of the invention

[0005] The technical problem to be solved by the present invention is: in view of the above-mentioned problems, a method and system for the cogeneration of biomass carbon and alcohol by coupling wind, solar, thermal and electricity is provided.

[0006] The technical solution adopted by the present invention is: a wind, photovoltaic, thermal and biomass carbon alcohol cogeneration method, characterized by comprising: The biomass raw materials are fed into a biomass carbonization charcoal gas cogeneration device to generate biochar and pyrolysis gas; The pyrolysis gas and water vapor are connected to the pyrolysis gas mixing burner, and sent to the pyrolysis gas electric heat reformer through the pyrolysis gas mixing burner, so that the tar gas and methane in the pyrolysis gas undergo endothermic reforming reaction with the water vapor and are converted into hydrogen and carbon monoxide to form a crude synthesis gas; The crude synthesis gas is sequentially input into the waste heat boiler, the boiler feed water preheater and the crude synthesis gas purification system to cool and purify the crude synthesis gas to form low-temperature purified synthesis gas; The purified synthesis gas is pressurized to form a synthesis raw gas, which is then fed into a methanol synthesis system, where part of the synthesis gas is converted into methanol, which is then condensed to form a gas-liquid mixture containing liquid methanol; The gas-liquid mixture containing liquid methanol is sent to a methanol gas-liquid separator to separate the liquid methanol; The liquid methanol is fed into the green crude methanol storage tank; The biomass carbonization charcoal gas cogeneration device comprises a gas burner and an electric heating module, wherein the gas source of the gas burner comprises one or more of the pyrolysis gas outputted from the biomass carbonization charcoal gas cogeneration device, the crude synthesis gas outputted from the pyrolysis gas electric heat converter, the low calorific value heavy component combustible gas outputted from the crude synthesis gas purification system, the purified synthesis gas and the purge gas outputted from the methanol gas-liquid separator; The power supply sources of the electric heating module and the pyrolysis gas electric thermal converter are both connected to the green power grid, and the green power grid is connected to the green power generation module, which includes one or more of a wind power generation module, a photovoltaic power generation module, a methanol internal combustion engine generator set and a steam turbine generator set.

[0007] The flue gas generated by the combustion of the gas burner for heating is cooled and condensed to remove moisture, and then compressed by a carbon dioxide compressor to condense and liquefy green carbon dioxide, and the liquid green carbon dioxide is separated and stored; The flue gas generated by the gas burner for heating is partially mixed with high-purity oxygen and then sent back to the gas burner.

[0008] The soft water is sequentially fed into the boiler feed water preheater and the waste heat boiler to generate water vapor with a certain pressure; Steam with a certain pressure is sent into the steam turbine generator set to drive the steam turbine generator set to generate electricity. The back pressure steam output by the steam turbine generator set after generating electricity is partially sent into the pyrolysis gas electric thermal converter; the remaining steam can be transported for external use. The unreacted synthesis gas separated by the methanol gas-liquid separator is pressurized and returned to the methanol synthesis system. The green crude methanol storage tank provides methanol fuel for the methanol internal combustion engine generator set.

[0009] By controlling the temperature and the amount of water vapor in the pyrolysis gas electric thermal reformer, the excess carbon monoxide and water vapor are adjusted to be converted into hydrogen and carbon dioxide, so that the hydrogen-to-carbon ratio in the crude synthesis gas is close to 2:1.

[0010] A wind, solar, thermal and electricity-coupled biomass carbon-alcohol polygeneration system, characterized by comprising: Biomass carbonization charcoal gas cogeneration device, used to process biomass raw materials into biochar and pyrolysis gas; A pyrolysis gas electric heat converter, whose pyrolysis gas mixing burner is connected to the biomass carbonization charcoal gas cogeneration device via a first pipeline, and is used to make tar gas and methane in the pyrolysis gas undergo endothermic reforming reaction with water vapor to convert them into hydrogen and carbon monoxide to form crude synthesis gas; A waste heat boiler is connected to the pyrolysis gas electric heat converter via a second pipeline, and is used to absorb high-temperature waste heat of the crude synthesis gas to reduce the temperature of the crude synthesis gas; a boiler feed water preheater, connected to the waste heat boiler via a third pipeline, for further reducing the temperature of the raw synthesis gas; A crude synthesis gas purification system is connected to the boiler feed water preheater via a fourth pipeline, and is used to desulfurize and decarbonize the crude synthesis gas, and adjust the hydrogen-carbon ratio to form purified synthesis gas; A synthesis gas compressor unit is connected to the raw synthesis gas purification system via a fifth pipeline, and is used to compress and purify the synthesis gas to form a synthesis raw gas that meets the requirements of the methanol synthesis process; a methanol synthesis system, connected to the synthesis gas compressor unit via a sixth pipeline, for generating methanol based on the synthesis feed gas to form a gas-liquid mixture containing liquid methanol; a methanol gas-liquid separator, connected to the methanol synthesis system via a seventh pipeline, and used for separating liquid methanol from a gas-liquid mixture containing liquid methanol; A green crude methanol storage tank, connected to the methanol gas-liquid separator via an eighth pipeline, for storing liquid green crude methanol; The biomass carbonization carbonization gas cogeneration device comprises a gas burner and an electric heating module, wherein the gas source of the gas burner comprises one or more of the pyrolysis gas output from the biomass carbonization carbonization gas cogeneration device, the crude synthesis gas output from the pyrolysis gas electric heat converter, the low calorific value recombinant combustible gas output from the crude synthesis gas purification system, the purified synthesis gas and the purge gas output from the methanol gas-liquid separator; The power supply sources of the electric heating module and the pyrolysis gas electric thermal converter are both connected to the green power grid, and the green power grid is connected to the green power generation module, which includes one or more of a wind power generation module, a photovoltaic power generation module, a methanol internal combustion engine generator set and a steam turbine generator set.

[0011] Also includes: A flue gas dehydration condenser is connected to the biomass carbonization charcoal gas cogeneration device via a ninth pipeline and is used to condense and dehydrate the flue gas generated by the combustion of the gas burner; a carbon dioxide condenser connected to the flue gas dehydration condenser via a tenth pipeline equipped with a carbon dioxide compressor, for condensing carbon dioxide in the liquefied flue gas to obtain liquefied green carbon dioxide; A liquefied green carbon dioxide storage tank, connected to the carbon dioxide condenser, for storing liquefied green carbon dioxide; A dry alkaline adsorption column, connected to the carbon dioxide condenser, for removing acidic gases from non-condensable gases; The eleventh pipeline connects the ninth pipeline and the gas burner. The eleventh pipeline is connected to an oxygen generator via the first oxygen supply pipeline, and is used to provide high-concentration oxygen to the gas burner to prepare oxygen-rich flue gas.

[0012] Also includes: A soft water storage tank is connected to the boiler soft water preheater and the waste heat boiler in sequence through pipelines; The steam turbine generator set has an input port connected to the waste heat boiler via a first steam pipeline, and an output port connected to a tee via a second steam pipeline, one of which is connected to the pyrolysis gas mixing burner of the pyrolysis gas electric thermal converter via a third steam pipeline, and the other output is used to supply surplus steam to the outside.

[0013] The third steam pipeline is equipped with a steam regulating valve, and the electric control end circuit of the steam regulating valve is connected to the temperature sensor of the pyrolysis gas electric thermal converter to form a closed-loop control so that the temperature in the pyrolysis gas electric thermal converter reaches the control requirement.

[0014] The gas outlet of the methanol gas-liquid separator is connected to the synthesis gas circulation booster pump through the twelfth pipeline, and then connected to the methanol synthesis system inlet through the thirteenth pipeline.

[0015] The crude green methanol storage tank is connected to the methanol internal combustion engine generator set via the fifteenth pipeline.

[0016] The pyrolysis gas mixing burner of the pyrolysis gas electric heat conversion furnace is connected to the oxygen generator through a second oxygen supply pipeline equipped with an oxygen regulating valve II; an ignition mechanism is provided corresponding to the pyrolysis gas mixing burner.

[0017] The electric control end circuit of the oxygen regulating valve II is connected to a crude synthesis gas outlet temperature sensor for using the crude synthesis gas temperature output by the pyrolysis gas electric heat converter.

[0018] A methanol internal combustion engine generator set is set up, and a closed-loop control is formed by the green grid voltage monitoring sensor and the methanol supply pipeline regulating valve of the methanol internal combustion engine generator set to automatically adjust the power generation to ensure stable power supply from the green grid; especially when the whole set of equipment stops running and the wind and photovoltaic power generation modules cannot supply power, the methanol internal combustion engine generator set generates electricity to provide lighting, maintenance and other services for the production plant, ensuring that the equipment can meet the safety of off-grid working electricity requirements on site.

[0019] The beneficial effects of the present invention are as follows: the wind, solar and thermal power of the present invention can increase the production of bio-green methanol by 80-90%. Compared with the electrolysis of water to produce hydrogen, the use of hydrogenation to increase the production of green methanol by converting carbon monoxide in the gasification gas can save 20% of electricity consumption for the same increase in green methanol production. In addition, the direct wind, solar and thermal power requires less than one twentieth of the electric heating process required for electrolysis of water to produce hydrogen, and the equipment maintenance is simple, avoiding the requirements for the highest safety protection level of electrolysis of water to produce hydrogen. In the case of a shortage of green electricity, normal production can still be carried out, but the energy of green methanol that can be increased by electric heating is converted into heat consumption.

[0020] In addition, this process achieves the co-production of biochar and alcohol, so that the total output of green methanol production costs, due to the multiple green energy outputs of biochar, bioelectricity, back pressure steam, and green carbon dioxide, the economic benefits obtained will greatly offset the overall cost of biomass methanol, making the total cost of biomass green methanol lower than fossil methanol.

[0021] Because the biomass charcoal industry is a mature and profitable industry, the volatile matter in the biomass during the charcoal making process needs to be removed as impurities. In conditional application scenarios, the pyrolysis gas can be used as gas to burn boilers to provide thermal services to the outside world and obtain additional revenue. In production scenarios where there are no conditions, the pyrolysis gas generated during the carbonization process is directly burned, and the exhaust gas heat is discharged into the atmosphere.

[0022] This process is to recycle the waste pyrolysis gas produced by biochar production to produce electricity, heat, green methanol and green carbon dioxide; plus biochar will produce carbon sinks of about 1:3. The original biochar industry did not consider carbon sink benefits in its profitability. Now, with the addition of carbon sink benefits, it has been calculated that as long as the price of biomass raw materials is not higher than 500 yuan / ton, the cost of green methanol produced by this process is equivalent to the cost of 3000kWh of green electricity per ton. Under the conditions of the highest on-grid electricity price of Southern Photovoltaic, which is 0.45 yuan / kWh, the cost of woody biomass raw materials is 500 yuan / ton and the price of wind and solar power is 0.45 yuan / kWh, the cost of green methanol produced by this process is 1350 yuan / ton, which is lower than coal chemical methanol (excluding carbon tax surcharges) and equivalent to natural gas methanol.

[0023] When green electricity is not available, according to this process, self-generated electricity can balance the electricity consumption of green methanol produced by the co-production of biomass charcoal and alcohol. As long as the cost of woody biomass raw materials is not higher than 500 yuan / ton and the cost of herbaceous biomass raw materials is not higher than 200 yuan / ton, the biochar and carbon sink income obtained can offset the entire production cost, making the output of bio-green methanol all belong to the net profit of this process. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of an embodiment.

[0025] 1. Biomass carbonization carbon gas cogeneration device; 2. Oxygen generator; 3. Oxygen regulating valve I; 4. Gas burner; 5. Oxygen regulating valve II; 5-1. Crude synthesis gas outlet temperature sensor; 6. Pyrolysis gas electric thermal converter; 7. Waste heat boiler; 8. Boiler feed water regulating valve; 8-1. Medium pressure steam superheat temperature sensor; 9. Boiler feed water preheater; 10. Crude synthesis gas purification system; 11. Purge gas regulating valve; 12. Synthesis gas circulation booster pump; 13. Methanol gas-liquid separator; 14. Green crude methanol tank; 15. Methanol internal combustion engine generator set; 15-1. Green grid voltage sensor; 15-2. Methanol regulating valve of methanol internal combustion generator set; 16. Methanol synthesis system; 17. Synthesis gas compressor unit; 18. Synthesis gas regulating valve; 19. Back pressure steam regulating valve; 20. Steam turbine generator set; 21. Steam regulating valve; 21-1. Electric heat conversion furnace temperature sensor; 22. Pyrolysis gas mixing burner; 22-1. Spark plug; 23-1. Pyrolysis gas regulating valve; 23. Pyrolysis gas high temperature resistant exhaust fan; 24. External combustion chamber flame temperature sensor; 24-1. Pyrolysis gas burnback regulating valve; 24-2. Synthesis gas burnback regulating valve; 25. Flue gas high temperature resistant exhaust fan; 26. Flue gas dehydration condenser; 27. Carbon dioxide compressor; 28. Carbon dioxide condenser; 29. ​​Dry alkaline adsorption column; 30. Liquid green carbon dioxide storage tank; 31. Cooling tower; 32. Circulating water pump; 33. Circulating flue gas regulating valve; 34. Cooling charcoal discharger. DETAILED DESCRIPTION

[0026] The present embodiment is a wind, solar, thermal and solar-coupled biomass charcoal-alcohol multi-generation system, including a biomass dry distillation charcoal-gas cogeneration device, a pyrolysis gas electric thermal converter, a waste heat boiler, a boiler feed water preheater, a crude synthesis gas purification system, a methanol synthesis system, a methanol gas-liquid separator, a green crude methanol storage tank, a methanol internal combustion engine generator set and a steam turbine generator set, etc.

[0027] In this example, the biomass carbonization charcoal gas cogeneration device has a gas burner and an electric heating module, wherein the gas burner is arranged in the external combustion chamber, and can utilize the low calorific value mixed combustible gas generated by the back-end process to burn and provide heat; the electric heating module circuit is connected to the green power grid, and the green power grid supplies power to the electric heating module, and the electric heating module converts electrical energy into thermal energy for heating.

[0028] In this embodiment, the biomass carbonization charcoal gas cogeneration device can generate biochar and pyrolysis gas from the biomass raw materials fed therein under the heat supply of the gas burner and the electric heating module.

[0029] In this embodiment, the pyrolysis gas outlet of the biomass carbonization charcoal gas cogeneration device is connected to the pyrolysis gas mixing burner on the pyrolysis gas electric thermal converter through the first pipeline. The pyrolysis gas electric thermal converter is powered by the green power grid, which can make the tar gas and methane in the pyrolysis gas undergo endothermic reforming reaction with water vapor to convert them into hydrogen and carbon monoxide to form crude synthesis gas.

[0030] In this example, a pyrolysis gas high-temperature resistant exhaust fan and a pyrolysis gas regulating valve are installed on the first pipeline. The electronic control end circuit of the pyrolysis gas regulating valve is connected to the electrothermal conversion furnace temperature sensor. The electrothermal conversion furnace temperature sensor is used to collect the temperature in the furnace of the pyrolysis gas electrothermal conversion furnace. The pyrolysis gas regulating valve adjusts its own valve opening based on the temperature in the furnace of the electrothermal conversion furnace.

[0031] In this embodiment, the pyrolysis gas high-temperature resistant exhaust fan and the pyrolysis gas regulating valve on the first pipeline are connected to the air inlet of the gas burner on the biomass dry distillation charcoal gas co-production device via a pyrolysis gas back-burning pipeline. A pyrolysis gas back-burning amount regulating valve is installed on the pyrolysis gas back-burning pipeline. The electrical control end circuit of the pyrolysis gas back-burning amount regulating valve is connected to the external combustion chamber flame temperature sensor. The external combustion chamber flame temperature sensor is used to collect the flame temperature of the gas burner. The pyrolysis gas back-burning amount regulating valve adjusts its own opening based on the flame temperature of the gas burner.

[0032] In this example, the crude synthesis gas outlet of the pyrolysis gas electric thermal converter is connected to the inlet of the first channel in the waste heat boiler via the second pipeline, the outlet of the first channel in the waste heat boiler is connected to the inlet of the first channel in the boiler feed water preheater via the third pipeline, and the outlet of the first channel in the boiler feed water preheater is connected to the inlet of the crude synthesis gas purification system via the fourth pipeline.

[0033] In this embodiment, the waste heat boiler can absorb the high-temperature waste heat of the crude synthesis gas and reduce the temperature of the crude synthesis gas; the boiler feed water preheater can further reduce the temperature of the crude synthesis gas; the crude synthesis gas purification system can desulfurize, decarbonize, and adjust the hydrogen-carbon ratio of the crude synthesis gas to form purified synthesis gas.

[0034] In this embodiment, the inlet of the second channel in the boiler feed water preheater is connected to the soft water storage tank via a pipeline, the outlet of the second channel in the boiler feed water preheater is connected to the inlet of the second channel in the waste heat boiler via a pipeline equipped with a boiler feed water regulating valve, the outlet of the second channel in the waste heat boiler is connected to the inlet of the steam turbine generator set via a first steam pipeline, and the outlet of the steam turbine generator set is connected to a three-way valve via a second steam pipeline, one of which is connected to the pyrolysis gas mixing burner of the pyrolysis gas electric thermal converter via a third steam pipeline, and the other is output through a back-pressure steam regulating valve to supply surplus steam to the outside. If the application scenario does not require steam, a condensing steam turbine generator set can be selected to improve the power generation rate.

[0035] In this example, the electrical control end of the boiler feed water regulating valve is connected to a medium-pressure steam superheat temperature sensor, which is used to collect the temperature of the water vapor in the first steam pipeline. The boiler feed water regulating valve adjusts its opening based on the water vapor temperature.

[0036] In this embodiment, a steam regulating valve is installed on the third steam pipeline. The electrical control end of the steam regulating valve is connected to a crude synthesis gas outlet temperature sensor. The crude synthesis gas outlet temperature sensor is used to collect the temperature of the crude synthesis gas in the second pipeline. The steam regulating valve adjusts its opening based on the temperature of the crude synthesis gas.

[0037] In this example, the purified synthesis gas outlet of the raw synthesis gas purification system is connected to the synthesis gas compressor unit via the fifth pipeline equipped with a synthesis gas regulating valve on the fifth pipeline. The synthesis gas compressor unit is used to compress and purify the synthesis gas to form a synthesis raw gas that meets the requirements of the methanol synthesis process.

[0038] In this embodiment, the methanol synthesis system is connected to the synthesis gas compressor unit via the sixth pipeline, and is used to generate methanol based on the synthesis feed gas output by the synthesis gas compressor unit.

[0039] In the present embodiment, the purified synthesis gas outlet of the crude synthesis gas purification system is connected to the air inlet of the gas burner on the biomass dry distillation charcoal gas co-production device through a synthesis gas burn-back pipeline. A synthesis gas burn-back amount regulating valve is installed on the synthesis gas burn-back pipeline. The electrical control end circuit of the synthesis gas burn-back amount regulating valve is connected to the external combustion chamber flame temperature sensor. The synthesis gas burn-back amount regulating valve adjusts its own opening based on the flame temperature of the gas burner.

[0040] In this example, the cleaned gas outlet of the crude synthesis gas purification system is connected to the air inlet of the gas burner on the biomass dry distillation charcoal gas cogeneration device through the sixteenth pipeline. The carbon dioxide mixed gas purified by the crude synthesis gas purification system contains some combustible gas, which is transported back to the charcoal gas cogeneration device for carbonization combustion and heat supply.

[0041] In this embodiment, the methanol synthesis system can catalytically synthesize methanol based on the purified hydrogen and carbon monoxide in the synthesis gas, and the product gas is cooled to condense methanol to form a gas-liquid mixture containing methanol. The outlet of the methanol synthesis system is connected to the inlet of the methanol gas-liquid separator through the seventh pipeline, and the methanol gas-liquid separator can separate liquid methanol from the gas-liquid mixture containing methanol through gas-liquid separation, and input it into the green crude methanol tank through the eighth pipeline.

[0042] In this example, the gas outlet Ⅰ of the methanol gas-liquid separator is connected to the synthesis gas circulation booster pump via the twelfth pipeline, and then connected to the sixth pipeline via the thirteenth pipeline and then connected to the methanol synthesis system; the gas outlet Ⅱ of the methanol gas-liquid separator is connected to the air inlet of the gas burner on the biomass dry distillation charcoal gas co-production device via the fourteenth pipeline, and a purge gas regulating valve is installed on the fourteenth pipeline.

[0043] In this embodiment, the liquid outlet of the methanol gas-liquid separator is connected to the inlet of the green crude methanol storage tank via the eighth pipeline, and the outlet of the green crude methanol storage tank is connected to the methanol internal combustion engine generator set via the fifteenth pipeline to provide methanol for the methanol internal combustion engine generator set. The methanol regulating valve of the methanol internal combustion generator set is installed on the fifteenth pipeline, and the electric control end circuit of the methanol regulating valve of the methanol internal combustion generator set is connected to the green grid voltage sensor that can collect the green grid voltage, and the opening of the methanol regulating valve of the methanol internal combustion generator set is controlled based on the green grid voltage.

[0044] In the present embodiment, the flue gas outlets of the inner and outer combustion chambers of the biomass carbonization carbon gas cogeneration device are connected to the flue gas dehydration condenser via the ninth pipeline, and then connected to the carbon dioxide condenser via the tenth pipeline, wherein the ninth pipeline is equipped with a flue gas high-temperature resistant exhaust fan; the flue gas dehydration condenser can condense and dehydrate the flue gas generated by the combustion of the gas burner; the tenth pipeline is equipped with a carbon dioxide compressor; the carbon dioxide condenser can condense the carbon dioxide in the liquefied flue gas to obtain liquefied green carbon dioxide.

[0045] In this example, a dry alkaline adsorption column is connected to the carbon dioxide condenser, and the non-condensable gas is used to remove acidic gas, which can achieve near-zero emissions and chimney-free production for the entire production.

[0046] In this embodiment, the liquefied green carbon dioxide storage tank is connected to the carbon dioxide condenser for storing liquefied green carbon dioxide.

[0047] In this example, the flue gas dehydration condenser and the carbon dioxide condenser are equipped with a cold water circulation system, which has a cooling tower and a circulating water pump, etc. The condensed water obtained by the flue gas dehydration condenser is supplemented into the cold water circulation system.

[0048] In this embodiment, the eleventh pipeline is connected to the ninth pipeline between the carbon dioxide compressor and the flue gas dehydration condenser, the eleventh pipeline is connected to the air inlet of the gas burner on the biomass carbonization charcoal gas cogeneration device, and a circulating flue gas regulating valve is installed on the eleventh pipeline.

[0049] In this example, after the eleventh flue gas regulating valve, before entering the gas burner, it is connected to the oxygen generator through the first oxygen supply pipeline, and the oxygen from the oxygen generator is connected to make oxygen-enriched flue gas and then enter the burner to assist combustion; the first oxygen supply pipeline is equipped with an oxygen regulating valve I, and the oxygen regulating valve I is linked with the circulating flue gas regulating valve to control the oxygen content of the oxygen-enriched flue gas returning to the gas burner.

[0050] In this embodiment, the oxygen generator is connected to the pyrolysis gas mixing burner of the pyrolysis gas electric heat converter via a second oxygen supply pipeline equipped with an oxygen regulating valve II, and an ignition mechanism (spark plug) is provided corresponding to the pyrolysis gas mixing burner.

[0051] In this example, the electrical control end circuit of the oxygen regulating valve II is connected to a crude synthesis gas outlet temperature sensor for measuring the temperature of the crude synthesis gas output by the pyrolysis gas electric thermal converter.

[0052] In this embodiment, the green power grid is connected to the green power generation module, and the green power generation module includes a wind power generation module, a photovoltaic power generation module, a methanol internal combustion engine generator set and a steam turbine generator set.

[0053] In this embodiment, an electric heating module is preferably used in combination with a combustible gas mixed with the clean gas and the purge gas of the raw synthesis gas purification system to provide heat. When the green electricity supply is insufficient or cut off, the pyrolysis gas or purified synthesis gas is turned on to supplement the heat to maintain the stable operation of the dry distillation carbon gas cogeneration device.

[0054] In this embodiment, the biomass carbonization charcoal gas cogeneration device is used for woody biomass and small-scale multi-rotary kiln equipment charcoal gas cogeneration, which can produce high-quality biochar and increase profits; for large-scale production, herbaceous biomass or waste woody biomass adopts double circulating fluidized bed charcoal gas cogeneration, and the produced powdered charcoal is then granulated to produce biochar granule products.

[0055] In this example, when green electricity is available, induction heating or electric heater array heating is used. The rotary kiln equipment is connected in series with an induction heating carbonization rotary kiln after the external combustion chamber carbonization kiln. The dry distillation fluidized bed is heated by an electric heater array in the solid heat carrier preheating fluidized bed.

[0056] In this embodiment, the biochar is output from the biomass carbonization charcoal gas co-generation device and is cooled by a cooling charcoal outlet machine to ensure that the biochar will not be naturally exposed to the air. High-quality special biochar can be cooled and isolated from oxygen protection by nitrogen generated by an oxygen generator.

[0057] In this example, the pyrolysis gas and biomass dry distillation charcoal gas co-production device is extracted by a high-temperature resistant (900℃) closed exhaust fan, and frequency conversion control is used to ensure a slight positive pressure in the biomass dry distillation chamber, and air will not leak into the dry distillation chamber, ensuring that the biomass carbonization pyrolysis is an anaerobic condition; the flue gas generated by external combustion heating is extracted by a high-temperature closed exhaust fan, and frequency conversion control is used to ensure that the external combustion chamber is under slight negative pressure control to prevent the flue gas from leaking into the production environment.

[0058] In this embodiment, the amount of steam mixed with the pyrolysis gas entering the burner is controlled in a closed loop by the temperature in the pyrolysis gas electric thermal converter, the electric heating power input, and the regulating valve on the steam pipeline, so that the input steam amount meets the steam ratio required for the endothermic reforming of the tar gas and methane gas contained in the pyrolysis gas, thereby achieving the control of the hydrogen-carbon ratio of the raw synthesis gas after the conversion.

[0059] In this example, when green electricity is insufficient, the electric heating temperature of the pyrolysis gas electric thermal converter cannot reach the preset temperature requirement. At this time, the third steam pipeline is cut off by the regulating valve, and the oxygen regulating valve II is opened, and oxygen is connected to the pyrolysis gas electric thermal converter through the second oxygen supply pipeline, and ignited and burned through the ignition mechanism. When green electricity is insufficient, the electric control end circuit of the oxygen regulating valve II on the pipeline connected to oxygen is connected to the crude synthesis gas outlet temperature sensor and the crude synthesis gas outlet temperature sensor output by the pyrolysis gas electric thermal converter to realize closed-loop control, maintaining the oxygen supply and the heat generated by the combustion of hydrogen and a small amount of methane gas in the pyrolysis gas to meet the heat required for endothermic reforming of tar gas and methane gas contained in the pyrolysis gas.

[0060] In this embodiment, a small-scale electric heating structure can be used for the pyrolysis gas electric heat converter, and a large-scale electric heating structure can be used for the electric heater matrix inside the converter.

[0061] In this embodiment, the methanol internal combustion engine generator set is used as a backup power source, and also as a spontaneous green power supply for lighting, office, equipment maintenance and repair, etc. in the factory area when there is no wind and solar power and the equipment stops production, so as to ensure zero carbon emissions under this process.

[0062] In this example, the crude synthesis gas purification system adopts the traditional purification process, which is composed of three sets of equipment: desulfurization, carbon monoxide conversion and carbon dioxide removal, and finally produces synthesis gas that meets the hydrogen-carbon ratio of the synthesis process. In this link, the light synthetic methanol process can be used to directly desulfurize and decarbonize and adjust the hydrogen-carbon ratio in one step.

[0063] In this embodiment, the wind power, photovoltaic power and thermal power coupled biomass carbon alcohol polygeneration method specifically includes the following process steps: S1. Send the biomass raw materials into the biomass carbonization charcoal gas cogeneration device to generate biochar and pyrolysis gas.

[0064] The pre-crushed biomass raw materials enter the electric-assisted heating biomass dry distillation carbon gas cogeneration unit, which adopts external combustion heating. The heating method is to use the low calorific value mixed combustible gas (clean gas and purge gas) generated by the back-end process to burn and heat. The insufficient part is heated by green electricity, so that the pyrolysis gas generated by carbonization pyrolysis can be used for synthesizing methanol as much as possible; the external combustion combustion control is to form a closed-loop control through the external combustion chamber flame temperature sensor (24) together with the pyrolysis gas backburning regulating valve (24-1) and the synthesis gas backburning regulating valve (24-2). Due to the electric heating assistance, in principle, these two parts of gas will only be opened when the green electricity supply is insufficient to reduce the output of green methanol and return to combustion; the biochar is output through the charcoal cooler on the unit equipment.

[0065] S2. The pyrolysis gas is pressurized by the exhaust fan, connected to the pyrolysis gas electric heat converter and the pyrolysis gas mixing burner on the waste heat utilization unit, mixed with steam in proportion, and enters the pyrolysis gas electric heat converter. It is heated by the electric heater array in the furnace or inductively heated to 1100-1300℃ for high-temperature reforming reaction, so that the tar gas and methane in the pyrolysis gas undergo endothermic reforming reaction with water vapor and are converted into hydrogen and carbon monoxide. In the absence of green electricity heating, the steam is turned off and the oxygen is turned on, so that the amount of oxygen entering and the water vapor and heat generated by the combustion of hydrogen contained in the pyrolysis gas meet the heat and water vapor required for the conversion of tar gas and methane in the pyrolysis gas.

[0066] A closed-loop control is formed by a steam regulating valve or an oxygen regulating valve II and a high-temperature crude synthesis gas temperature sensor to control the side reaction of carbon monoxide and water vapor into hydrogen and carbon dioxide, so that the hydrogen-carbon ratio (H2:CO) in the crude synthesis gas is close to 2:1, which is convenient for subsequent purification to form synthesis gas.

[0067] S3. The crude synthesis gas is sequentially input into the waste heat boiler, the boiler feed water preheater and the crude synthesis gas purification system to cool and purify the crude synthesis gas to form a low-temperature purified synthesis gas.

[0068] The crude synthesis gas with a high temperature of about 1300℃ enters the waste heat boiler to produce medium-pressure steam (3.5-5.0MPa) for steam turbine power generation and back-pressure steam (0.7-0.8MPa) for other applications; the crude synthesis gas after recovering the high-temperature waste heat is cooled to below 50℃ by the boiler feed water preheater.

[0069] The low-temperature crude synthesis gas is desulfurized, decarbonized, and the hydrogen-carbon ratio is adjusted in the crude synthesis gas purification system to form purified synthesis gas. The hydrogen-carbon ratio is adjusted to 2.1-2.2:1 and input into the methanol synthesis system; the carbon dioxide mixed gas (net gas) produced by purification contains some combustible gas, which is transported back to the carbon-gas cogeneration unit for carbonization combustion and heat supply.

[0070] S4. Pressurize the purified synthesis gas to form synthesis raw gas, which is sent to a methanol synthesis system to generate methanol and form a gas-liquid mixture containing methanol.

[0071] The purified synthesis gas is compressed to the process pressure (the catalyst adapts to the pressure of 3.0-8.0MPa, and the commonly used preferred pressure is 5.0MPa) by the synthesis gas compressor unit, and is transported to the methanol synthesis system. It is preheated to 200-230℃ before entering the catalytic synthesis section (depending on the process requirement parameters of the synthesis catalyst used); the synthesis gas passes through the catalyst synthesis section, and part of the synthesis gas is converted into methanol. The conversion rate is related to the catalyst characteristics and working pressure. The produced finished gas is cooled and condensed to form a gas-liquid mixture containing liquid methanol.

[0072] S5. Send the mixed fluid containing methanol liquid into a methanol gas-liquid separator to separate liquid methanol; and send the liquid methanol into a green crude methanol storage tank.

[0073] If liquid methanol needs to be purified into green refined methanol, it can be further distilled into green refined methanol through a distillation tower and sent to the refined methanol storage tank for sale outside the factory; part of the unreacted synthesis gas is separated as purge gas and incorporated into the mixed combustible gas for use as carbonization heating fuel; most of it is pressurized by a circulating booster pump and incorporated into the pre-preheated raw gas, and preheated together into the synthesis system to continue synthesizing methanol.

[0074] In the present embodiment, both steps S1 and S2 carry out biomass decomposition and conversion under low-pressure and anaerobic conditions. After efficient waste heat and electric heat utilization, the obtained room-temperature crude synthesis gas can be subjected to desulfurization, carbon monoxide conversion and carbon dioxide removal in a conventional coal chemical industry, and finally obtain synthesis gas meeting the hydrogen-to-carbon ratio requirements for synthetic methanol. Here, a room-temperature and low-pressure adsorption separation process can also be used to remove carbon dioxide and other acidic gases, and at the same time adjust the hydrogen-to-carbon ratio to obtain a purified synthesis gas meeting the hydrogen-to-carbon ratio requirements for synthetic methanol.

[0075] Compared with the two crude synthesis gas processes, the latter will produce mixed combustible gas with low calorific value, because the adsorption separation method has low energy consumption and simple process, but it will lose some hydrogen and carbon monoxide combustible gas into the carbon dioxide impurity gas. Because the biomass carbon gas co-production in the previous process belongs to the external combustion process, the low calorific value mixed combustible gas produced by adsorption separation can be returned to the front for external combustion carbonization heating, and also provide a good way to utilize the purge gas produced in the subsequent synthetic methanol unit system. That is, the purge gas produced by synthetic methanol can be collected together with the low calorific value mixed combustible gas produced by crude synthesis gas purification for external combustion carbonization heating.

[0076] In this way, the entire process only produces combustion tail gas in the external combustion chamber of the carbon-gas cogeneration device, which is the only combustion tail gas in the process and becomes flue gas here. Therefore, by using partial flue gas circulation and oxygen distribution to form nitrogen-free combustion, it is very convenient to achieve green carbon dioxide capture and liquefy and separate green carbon monoxide. The total amount of non-condensable gases in the flue gas is reduced by more than 95%, and various acidic gases can easily and economically achieve the new most advanced level of near-zero emissions through dry alkaline adsorption columns, and achieve chimney-free production of the entire system.

Claims

1. A wind, solar, thermal and electricity-coupled biomass carbon-alcohol cogeneration method, characterized in that: include: The biomass raw materials are fed into a biomass carbonization charcoal gas cogeneration device to generate biochar and pyrolysis gas; The pyrolysis gas and water vapor are connected to the pyrolysis gas mixing burner, and sent to the pyrolysis gas electric heat reformer through the pyrolysis gas mixing burner, so that the tar gas and methane in the pyrolysis gas undergo endothermic reforming reaction with the water vapor and are converted into hydrogen and carbon monoxide to form a crude synthesis gas; The crude synthesis gas is sequentially input into the waste heat boiler, the boiler feed water preheater and the crude synthesis gas purification system to cool and purify the crude synthesis gas to form low-temperature purified synthesis gas; The purified synthesis gas is pressurized to form a synthesis raw gas, which is then fed into a methanol synthesis system, where part of the synthesis gas is converted into methanol, which is then condensed to form a gas-liquid mixture containing liquid methanol; The gas-liquid mixture containing liquid methanol is sent to a methanol gas-liquid separator to separate the liquid methanol; The liquid methanol is fed into the green crude methanol storage tank; The biomass carbonization charcoal gas cogeneration device comprises a gas burner and an electric heating module, wherein the gas source of the gas burner comprises one or more of the pyrolysis gas outputted from the biomass carbonization charcoal gas cogeneration device, the crude synthesis gas outputted from the pyrolysis gas electric heat converter, the low calorific value heavy component combustible gas outputted from the crude synthesis gas purification system, the purified synthesis gas and the purge gas outputted from the methanol gas-liquid separator; The power supply sources of the electric heating module and the pyrolysis gas electric thermal converter are both connected to the green power grid, and the green power grid is connected to the green power generation module, which includes one or more of a wind power generation module, a photovoltaic power generation module, a methanol internal combustion engine generator set and a steam turbine generator set.

2. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration method according to claim 1 is characterized by: The flue gas generated by the combustion of the gas burner for heating is cooled and condensed to remove moisture, and then compressed by a carbon dioxide compressor to condense and liquefy green carbon dioxide, and the liquid green carbon dioxide is separated and stored; The flue gas generated by the gas burner for heating is partially mixed with high-purity oxygen and then sent back to the gas burner.

3. The wind, solar, thermal and biomass carbon-alcohol cogeneration method according to claim 1 is characterized by: The soft water is sequentially fed into the boiler feed water preheater and the waste heat boiler to generate water vapor with a certain pressure; Steam with a certain pressure is sent into the steam turbine generator set to drive the steam turbine generator set to generate electricity. The back pressure steam output by the steam turbine generator set after generating electricity is partially sent into the pyrolysis gas electric thermal converter; the remaining steam can be transported for external use.

4. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration method according to claim 1 is characterized by: The unreacted synthesis gas separated by the methanol gas-liquid separator is pressurized and returned to the methanol synthesis system.

5. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration method according to claim 1 is characterized by: The green crude methanol storage tank provides methanol fuel for the methanol internal combustion engine generator set.

6. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration method according to claim 1 is characterized by: By controlling the temperature and the amount of water vapor in the pyrolysis gas electric thermal reformer, the excess carbon monoxide and water vapor are adjusted to be converted into hydrogen and carbon dioxide, so that the hydrogen-to-carbon ratio in the crude synthesis gas is close to 2:

1.

7. A wind, solar, thermal and electricity-coupled biomass carbon-alcohol cogeneration system, characterized in that: include: Biomass carbonization charcoal gas cogeneration device, used to process biomass raw materials into biochar and pyrolysis gas; A pyrolysis gas electric heat converter, whose pyrolysis gas mixing burner is connected to the biomass carbonization charcoal gas cogeneration device via a first pipeline, and is used to make tar gas and methane in the pyrolysis gas undergo endothermic reforming reaction with water vapor to convert them into hydrogen and carbon monoxide to form crude synthesis gas; A waste heat boiler is connected to the pyrolysis gas electric heat converter via a second pipeline, and is used to absorb high-temperature waste heat of the crude synthesis gas to reduce the temperature of the crude synthesis gas; a boiler feed water preheater, connected to the waste heat boiler via a third pipeline, for further reducing the temperature of the raw synthesis gas; A crude synthesis gas purification system is connected to the boiler feed water preheater via a fourth pipeline, and is used to desulfurize and decarbonize the crude synthesis gas, and adjust the hydrogen-carbon ratio to form purified synthesis gas; A synthesis gas compressor unit is connected to the raw synthesis gas purification system via a fifth pipeline, and is used to compress and purify the synthesis gas to form a synthesis raw gas that meets the requirements of the methanol synthesis process; a methanol synthesis system, connected to the synthesis gas compressor unit via a sixth pipeline, for generating methanol based on the synthesis feed gas to form a gas-liquid mixture containing liquid methanol; a methanol gas-liquid separator, connected to the methanol synthesis system via a seventh pipeline, and used for separating liquid methanol from a gas-liquid mixture containing liquid methanol; A green crude methanol storage tank, connected to the methanol gas-liquid separator via an eighth pipeline, for storing liquid green crude methanol; The biomass carbonization carbonization gas cogeneration device comprises a gas burner and an electric heating module, wherein the gas source of the gas burner comprises one or more of the pyrolysis gas output from the biomass carbonization carbonization gas cogeneration device, the crude synthesis gas output from the pyrolysis gas electric heat converter, the low calorific value recombinant combustible gas output from the crude synthesis gas purification system, the purified synthesis gas and the purge gas output from the methanol gas-liquid separator; The power supply sources of the electric heating module and the pyrolysis gas electric thermal converter are both connected to the green power grid, and the green power grid is connected to the green power generation module, which includes one or more of a wind power generation module, a photovoltaic power generation module, a methanol internal combustion engine generator set and a steam turbine generator set.

8. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 7 is characterized in that: Also includes: A flue gas dehydration condenser is connected to the biomass carbonization charcoal gas cogeneration device via a ninth pipeline and is used to condense and dehydrate the flue gas generated by the combustion of the gas burner; a carbon dioxide condenser connected to the flue gas dehydration condenser via a tenth pipeline equipped with a carbon dioxide compressor, for condensing carbon dioxide in the liquefied flue gas to obtain liquefied green carbon dioxide; A liquefied green carbon dioxide storage tank, connected to the carbon dioxide condenser, for storing liquefied green carbon dioxide; A dry alkaline adsorption column, connected to the carbon dioxide condenser, for removing acidic gases from non-condensable gases; The eleventh pipeline connects the ninth pipeline and the gas burner. The eleventh pipeline is connected to an oxygen generator via the first oxygen supply pipeline, and is used to provide high-concentration oxygen to the gas burner to prepare oxygen-rich flue gas.

9. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 7 is characterized in that: Also includes: A soft water storage tank is connected to the boiler soft water preheater and the waste heat boiler in sequence through pipelines; The steam turbine generator set has an input port connected to the waste heat boiler via a first steam pipeline, and an output port connected to a tee via a second steam pipeline, one of which is connected to the pyrolysis gas mixing burner of the pyrolysis gas electric thermal converter via a third steam pipeline, and the other output is used to supply surplus steam to the outside.

10. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 9 is characterized by: The third steam pipeline is equipped with a steam regulating valve, and the electric control end circuit of the steam regulating valve is connected to the temperature sensor of the pyrolysis gas electric thermal converter to form a closed-loop control so that the temperature in the pyrolysis gas electric thermal converter reaches the control requirement.

11. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 7 is characterized by: The gas outlet of the methanol gas-liquid separator is connected to the synthesis gas circulation booster pump through the twelfth pipeline, and then connected to the methanol synthesis system inlet through the thirteenth pipeline.

12. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 7 is characterized by: The crude green methanol storage tank is connected to the methanol internal combustion engine generator set via the fifteenth pipeline.

13. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 7 is characterized by: The pyrolysis gas mixing burner of the pyrolysis gas electric heat conversion furnace is connected to the oxygen generator through a second oxygen supply pipeline equipped with an oxygen regulating valve II; an ignition mechanism is provided corresponding to the pyrolysis gas mixing burner.

14. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration system according to claim 13, characterized in that: The electric control end circuit of the oxygen regulating valve II is connected to a crude synthesis gas outlet temperature sensor for using the crude synthesis gas temperature output by the pyrolysis gas electric heat converter.

15. The wind, photovoltaic, thermal and biomass carbon-alcohol cogeneration method according to claim 1, characterized in that: A methanol internal combustion engine generator set is set up, and a closed-loop control is formed by the green grid voltage monitoring sensor and the methanol supply pipeline regulating valve of the methanol internal combustion engine generator set to automatically adjust the power generation to ensure stable power supply from the green grid; especially when the whole set of equipment stops running and the wind and photovoltaic power generation modules cannot supply power, the methanol internal combustion engine generator set generates electricity to provide lighting, maintenance and other services for the production plant, ensuring that the equipment can meet the safety of off-grid working electricity requirements on site.

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