Method and system for co-production of light synthesis green methanol from biomass charcoal alcohol

Abstract

The invention relates to a method and a system for co-production of light synthesis green methanol from biomass charcoal alcohol. The method is suitable for green energy industry. The technical scheme adopted by the invention is as follows: the method comprises the following steps: feeding a biomass raw material into a biomass charcoal-gas co-production device to generate charcoal and pyrolysis gas; feeding the pyrolysis gas and oxygen into a dry reforming burner, and feeding the pyrolysis gas and oxygen into a dry reforming furnace through the dry reforming burner to form high-temperature crude synthesis gas; feeding the high-temperature crude synthesis gas into a waste heat utilization device to form low-temperature crude synthesis gas; feeding the low-temperature crude synthesis gas into a light and heavy component separation device, and separating and purifying the low-temperature crude synthesis gas to form purified synthesis gas of which the carbon-hydrogen ratio meets a preset condition; pressurizing the purified synthesis gas to form synthesis raw material gas, feeding the synthesis raw material gas into a methanol synthesis system, partially converting into methanol, and condensing to form a gas-liquid mixture containing liquid methanol; feeding the gas-liquid mixture containing the liquid methanol into a methanol gas-liquid separator, and separating out the liquid methanol; and feeding the liquid methanol into a crude methanol storage tank.

Description

Technical Field

[0001] The present invention relates to a method and system for co-producing light synthetic green methanol from biomass charcoal and alcohol, which is applicable to the green energy industry. Background Art

[0002] With the requirements of "dual carbon" energy and environmental protection, the international carbon tax on imported goods is about to be implemented. Therefore, the solid sunlight contained in biomass - biochar, can be separated separately through new equipment for carbon-gas co-production through distillation process, which can further improve the economic value of biomass energy. At the same time, this is also the only way for mankind to economically obtain carbon sinks - green carbon sources in large quantities.

[0003] Since the biomass dry distillation process belongs to the external combustion pyrolysis process, the purification process of the biogasification gas obtained by gasifying the traditional biomass as inferior coal is too long and too complicated. The purification process of the traditional biomass gasification gas adopts a five-step purification process, including water-washed tar purification, pressurized heating desulfurization, CO conversion, high-temperature CH4 conversion, low-temperature and low-pressure CO2 removal, and finally forms a purified synthesis gas with a hydrogen-carbon ratio of 2.1-2.2:1. In the traditional gasification gas purification process, there is also a method of using dry reforming to convert tar gas and methane gas, but it is still necessary to first perform desulfurization, then perform CO catalytic conversion and remove CO2 and other three unit processes to ensure that a clean synthesis gas that meets the hydrogen-carbon ratio is obtained. The number of links is increased, and it is difficult to meet the requirements of miniaturization.

[0004] In addition, if the heat source fuel required for external combustion biomass charcoal-gas cogeneration is directly burned with pyrolysis gas for heating, precious hydrogen will be lost and the output rate of green methanol will be lost.

[0005] According to the identification rules of green methanol, the electricity used in the production process needs to be green electricity. When the green external electricity supply is insufficient, it is necessary to use the gas in the system to supplement the self-generation in time. Therefore, the low-temperature crude synthesis gas and the recombinant gas in the present invention are clean gases after the tar gas is removed, which can be directly connected to the gas-fired generator set to achieve timely adjustment. Summary of the invention

[0006] The technical problem to be solved by the present invention is: in view of the above-mentioned existing problems, a method and system for co-producing light synthetic green methanol from biomass charcoal and alcohol is provided.

[0007] The technical solution adopted by the present invention is: a method for co-producing light synthetic green methanol from biomass carbon alcohol, characterized by comprising: The biomass raw materials are fed into a biomass charcoal-gas cogeneration device to generate biochar and pyrolysis gas; The pyrolysis gas and oxygen are connected to the dry reforming burner and sent into the dry reforming furnace by the dry reforming burner, so that the oxygen and hydrogen in the pyrolysis gas are burned to produce water vapor, and the tar gas and methane in the pyrolysis gas react with the water vapor to produce hydrogen and carbon monoxide, forming a high-temperature crude synthesis gas; The high-temperature crude synthesis gas is sent to a waste heat utilization device to form a low-temperature crude synthesis gas; The low-temperature crude synthesis gas is sent to a light-heavy component separation device to separate and purify the low-temperature crude synthesis gas to form a purified synthesis gas whose carbon-hydrogen ratio meets preset conditions; The purified synthesis gas is pressurized to form a synthesis raw gas, which is then fed into a methanol synthesis system, partially converted into methanol, and 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; sending liquid methanol into a crude methanol storage tank; The light and heavy component separation device separates and purifies the low-temperature raw synthesis gas, including: The low-temperature crude synthesis gas is pressurized and sent to the main adsorption tower. The gas that passes through the main adsorption tower within a preset time is sent to the light component gas tank as purified synthesis gas. The gas retained in the main adsorption tower after the preset time is pumped to the heavy component gas tank.

[0008] Part of the flue gas generated by the external combustion chamber burner in the biomass charcoal-gas cogeneration device is mixed with high-purity oxygen and then sent back to the external combustion chamber burner.

[0009] The waste heat utilization device absorbs the heat of the high-temperature raw synthesis gas through the waste heat boiler, heats the soft water to form water vapor with a certain pressure; and sends the water vapor with a certain pressure to the steam turbine generator set to drive the steam turbine generator set to generate electricity.

[0010] The waste heat utilization device also absorbs the heat of the high-temperature raw synthesis gas through the raw synthesis gas cooler, heats the soft water and then supplies it into the waste heat boiler.

[0011] Through the standby boiler, the crude synthesis gas is used as fuel gas to heat soft water to form water vapor with a certain pressure; the water vapor with a certain pressure is sent to the steam turbine generator set to drive the steam turbine generator set to generate electricity.

[0012] The light component gas tank includes a light component gas tank A and a light component gas tank B; The low-temperature crude synthesis gas is pressurized and sent to the main adsorption tower. The gas that passes through the main adsorption tower within a preset time is sent to the light component gas tank A or B as purified synthesis gas. At this time, the purified synthesis gas in the other light component gas tank is pressurized to form synthesis raw gas and sent to the methanol synthesis system; The gas retained in the main adsorption tower after a preset time is pumped to the recombinant gas tank.

[0013] A biomass carbon alcohol co-production light synthetic green methanol system, characterized by comprising: Biomass charcoal and gas cogeneration device, used to process biomass raw materials into biochar and pyrolysis gas; A dry reforming furnace, wherein the dry reforming burner is connected to the biomass charcoal gas cogeneration device via a first pipeline and is also connected to the oxygen generator via a second pipeline, for burning oxygen with hydrogen in the pyrolysis gas to produce water vapor, and reacting tar gas and methane in the pyrolysis gas with the water vapor to produce hydrogen and carbon monoxide, thereby forming a high-temperature crude synthesis gas; A waste heat utilization device, connected to the dry reforming furnace via a third pipeline, for reducing the temperature of the high-temperature crude synthesis gas to form a low-temperature crude synthesis gas; A light-heavy component separation device, connected to the waste heat utilization device via a fifth pipeline, for separating and purifying the low-temperature raw synthesis gas to form a purified synthesis gas with a carbon-to-hydrogen ratio that meets a preset condition; A methanol synthesis system is connected to the light-heavy component separation device via a sixth pipeline equipped with a synthesis gas compressor unit, and is used to convert part of the synthesis raw gas formed by pressurizing the purified synthesis gas into methanol, and condense it 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 crude methanol storage tank, connected to the methanol gas-liquid separator via an eighth pipeline, for storing liquid methanol; The light and heavy component separation device comprises: The main adsorption tower, the bottom of which is connected to the air inlet of the light and heavy component separation device through a separation air inlet valve and an air pump; the bottom of which is connected to the heavy component gas tank through a heavy component valve and an air pump; The light component gas tank has an air inlet connected to the top of the main adsorption tower via a light component air inlet valve, and a light component gas tank air outlet connected to the air outlet of the light-heavy component separation device via a light component air outlet valve.

[0014] Also includes: A carbon dioxide capture module is connected to the external combustion chamber in the biomass charcoal and gas cogeneration device through a tenth pipeline, and is used to capture carbon dioxide in the flue gas generated by the burners in the internal and external combustion chambers of the biomass charcoal and gas cogeneration device; The eleventh pipeline has one end connected to the external combustion chamber in the biomass charcoal gas cogeneration device, and the other end connected to the burner in the external combustion chamber. The eleventh pipeline is connected to the oxygen generator via the twelfth pipeline to provide high-concentration oxygen to the gas burner to prepare oxygen-rich flue gas.

[0015] The waste heat utilization device comprises: A waste heat boiler, wherein the first channel inlet is connected to the dry reforming furnace via the third pipeline; The inlet of the steam turbine generator set is connected to the outlet of the second channel in the waste heat boiler via the fourteenth pipeline, and the outlet of the steam turbine generator set is connected to the inlet of the second channel in the waste heat boiler via the fifteenth pipeline.

[0016] The waste heat utilization device further comprises: A raw syngas cooler, wherein the first channel inlet is connected to the first channel outlet of the waste heat boiler via a fourth pipeline; the second channel inlet of the raw syngas cooler is connected to the soft water storage tank, and the second channel outlet is connected to the fifteenth pipeline via a sixteenth pipeline equipped with a hot soft water supplement regulating valve; The electric control end circuit of the hot soft water supplement regulating valve is connected to the steam turbine condensate return water flow meter, and the steam turbine condensate return water flow meter is installed on the fifteenth pipeline.

[0017] The fifteenth pipeline is connected to the standby boiler via the seventeenth pipeline, and the standby boiler is connected to the fourteenth pipeline via the eighteenth pipeline; The standby boiler burner of the standby boiler is connected to the raw synthesis gas cooled by the waste heat utilization device, and is connected to the oxygen generator through the thirteenth pipeline.

[0018] The light component gas tank includes a light component gas tank A and a light component gas tank B; The air inlet of the light component gas tank A is connected to the top of the main adsorption tower through the light component air inlet valve A, and the air outlet of the light component gas tank A is connected to the air outlet of the light and heavy component separation device through the light component air outlet valve A; The air inlet of the light component gas tank B is connected to the top of the main adsorption tower through the light component air inlet valve B, and the air outlet of the light component gas tank B is connected to the air outlet of the light-heavy component separation device through the light component air outlet valve B.

[0019] The methanol synthesis system comprises: A methanol condenser, wherein the first channel inlet is connected to the sixth pipeline; A methanol synthesis tower, whose lower inlet is connected to the first channel outlet in the methanol condenser via a nineteenth pipeline, and whose upper outlet is connected to the second channel inlet in the methanol condenser via a twentieth pipeline; A finished gas cooler, whose inlet is connected to the outlet of the second channel in the methanol condenser, and whose outlet is connected to the methanol gas-liquid separator.

[0020] The methanol gas-liquid separator is connected to the burners of the inner and outer combustion chambers of the biomass charcoal-gas cogeneration device via a twenty-first pipeline; And / or, the recombinant gas tank is connected to the burners of the inner and outer combustion chambers of the biomass charcoal-gas cogeneration device via the twenty-second pipeline.

[0021] The beneficial effects of the present invention are as follows: the present invention performs a two-step purification on the generated pyrolysis gas through a light and heavy component separation device, and generates a purified synthesis gas with a hydrogen-carbon ratio of 2.1-2.2:1, which can directly enter the methanol synthesis system to produce green methanol; at the same time, the output heavy component combustible gas and the purge gas generated by the synthetic methanol are combined to become the burners in the internal and external combustion chambers of the front-end biomass carbon-gas cogeneration device to provide biomass heat self-balancing combustible gas.

[0022] In the present invention, a light-heavy component separation device is designed based on the weight of each gas component in the crude synthesis gas. The crude synthesis gas enters the main adsorption tower from the bottom of the main adsorption tower. The main adsorption tower separates the target heavy component with CO2 as the target, and CO2 and other gases such as SO2 that are heavier than CO2 are retained in the main adsorption tower. H2 and CO that are lighter than CO2 preferentially enter the light component gas tank upward, and then all the gases retained in the main adsorption tower are pumped into the heavy component gas tank by using a vacuum pump, thereby achieving purification of the crude synthesis gas.

[0023] In the present invention, since H2 is much lighter than CO, more CO is retained in the main adsorption tower than H2 and enters the heavy component gas. The composition of the light component gas entering the light component gas tank from the main adsorption tower basically meets the requirements for synthesizing methanol and reaches the standard of a hydrogen-to-carbon ratio of 2.1-2.2:1.

[0024] The present invention introduces the separation of light and heavy components, and uses carbon dioxide as the heavy component target gas to separate light and heavy components, which greatly simplifies the purification process of pyrolysis gas, greatly reduces the production cost of biomass to methanol, enables the equipment to be miniaturized, is more conducive to the energy utilization of agricultural straw, saves the cost of remote centralized storage and transportation of straw, and can form straw methanol agricultural machinery, transforming the straw energy production link into the production link of farmers, so that agriculture can achieve the transformation and upgrading of food agriculture to food-energy co-production agriculture.

[0025] The present invention adopts a constant temperature methanol synthesis system to control the synthesis exothermic process without overheating. In addition, two parts of carbon monoxide and two parts of hydrogen produce one part of methanol. The volume of the reactants is reduced by 3:1 during the synthesis process. Therefore, the safety issues of the constant temperature methanol synthesis system are similar to the control of pressure vessels, and there are no other safety hazards. The safety management of simple pressure vessels does not require production in chemical parks, which can open up new prospects for agricultural green energy production.

[0026] In the present invention, all gases entering the recombinant gas include a small portion of carbon monoxide and hydrogen, so that the recombinant gas can be returned to the biomass carbon gas cogeneration device as fuel for heating. The present invention uses an external combustion chamber burner to burn the recombinant gas and purge gas produced by the subsequent unit, and adds part of the crude synthesis gas to reduce the direct use of pyrolysis gas and synthesis gas, reduce hydrogen loss, and ensure the output rate of green methanol.

[0027] The light synthetic methanol process of the present invention can obtain purified synthesis gas with a hydrogen-to-carbon ratio that meets the requirements of the synthesis process from biothermal decomposition gas in a two-step process without a catalyst and under normal pressure, and directly supply the purified synthesis gas to the back-end synthetic methanol, thereby simplifying the process of the new process, saving about 30% in equipment investment, saving 30% in land area, and saving about 20% in energy consumption because the entire purification process is at normal pressure, and the purified synthesis gas is formed and then enters the synthetic methanol unit for pressurization, making it easier to produce green methanol from biomass, and especially realizing the mechanized production of straw methanol, which will increase production and income for farmers and contribute to the economic transformation of promoting carbon neutrality in agriculture.

[0028] Figure 1 This is a process flow chart of the biomass carbon alcohol co-production of light synthetic green methanol in the embodiment.

[0029] Figure 2 Schematic diagram of the biomass charcoal-gas cogeneration device in the embodiment.

[0030] Figure 3 It is a schematic diagram of the dry reforming furnace and waste heat utilization device in the embodiment.

[0031] Figure 4 Schematic diagram of the light and heavy component separation device in the embodiment.

[0032] Figure 5 Schematic diagram of the methanol synthesis system in the embodiment.

[0033] 1. Net exhaust flue gas exhaust fan; 2. Biomass charcoal gas cogeneration device; 2-1. Cooling charcoal discharger; 3. Pyrolysis gas exhaust fan; 3-1. Circulating combustion pyrolysis gas exhaust fan; 4. External combustion chamber burner; 5. Gas regulating valve; 6. External combustion chamber flame temperature sensor; 7. Oxygen-enriched flue gas oxygen distribution regulating valve; 8. Oxygen generator; 9. Circulating flue gas regulating valve; 10. Circulating flue gas exhaust fan.

[0034] 11. Pyrolysis gas regulating valve; 12. Dry reforming burner; 13. Waste heat steam boiler; 14. Steam turbine generator set; 15. Steam turbine condensate return water flowmeter; 16. Hot soft water supplement regulating valve; 17. Crude synthesis gas cooler; 18. Crude synthesis gas branch regulating valve; 19. Internal combustion engine fuel gas control regulating valve; 20. Gas internal combustion engine generator set; 21. Dry reforming oxygen regulating valve; 22. Dry reforming furnace outlet temperature sensor; 23. Dry reforming furnace.

[0035] 31. Crude synthesis gas regulating valve; 32. Heavy component valve; 33. Main adsorption tower; 34. Light component air inlet valve A; 35. Light component gas tank A; 36. Light component gas tank B; 37. Heavy component gas tank; 38. Vacuum pump.

[0036] 41. Synthesis gas regulating valve; 42. Synthesis gas compressor unit; 43. Synthesis methanol tower; 44. Thermal oil electric heater; 45. Thermal oil condenser; 46. Methanol condenser; 47. Methanol internal combustion engine generator set; 48. Internal combustion engine methanol supply regulating valve; 49. Crude methanol output valve; 50. Crude methanol storage tank; 51. Finished gas cooler; 52. Methanol gas-liquid separator; 53. Purge gas regulating valve; 54. Circulating synthesis gas booster pump; 55. Thermal oil circulating pump. DETAILED DESCRIPTION

[0037] like Figure 1 As shown, this embodiment is a biomass charcoal-alcohol co-production light synthetic green methanol system, including a biomass charcoal-gas co-production device, a dry reforming furnace, a waste heat utilization device, a light and heavy component separation device, a methanol synthesis system, a methanol gas-liquid separator and a crude methanol storage tank.

[0038] In this example, the biomass charcoal-gas cogeneration device has a cooling charcoal discharger for outputting the biochar produced by carbonization, and an external combustion chamber equipped with an external combustion chamber burner.

[0039] like Figure 2 As shown, the flue gas outlet of the biomass charcoal gas cogeneration device in this embodiment is connected to the carbon dioxide capture module through the tenth pipeline equipped with a net exhaust flue gas exhaust fan, and the carbon dioxide in the flue gas is captured by the carbon dioxide capture module.

[0040] In this example, the tenth pipeline is connected to the burner in the external combustion chamber through the eleventh pipeline equipped with a circulating flue gas exhaust fan and a circulating flue gas regulating valve. The eleventh pipeline is connected to the oxygen generator through the twelfth pipeline equipped with an oxygen-enriched flue gas oxygen distribution regulating valve, which is used to provide high-concentration oxygen to the gas burner to prepare oxygen-enriched flue gas. In this example, the electric control end of the oxygen-enriched flue gas oxygen distribution regulating valve is connected to the electric control end circuit of the circulating flue gas regulating valve, and the two regulating valves cooperate with each other to control the oxygen content in the oxygen-enriched flue gas within a preset range.

[0041] like Figure 3 As shown, the dry reforming burner of the dry reforming furnace in this embodiment is connected to the pyrolysis gas outlet of the biomass charcoal gas cogeneration device through a first pipeline equipped with a pyrolysis gas exhaust fan and a pyrolysis gas regulating valve, and the dry reforming burner is also connected to the oxygen generator through a second pipeline equipped with a dry reforming oxygen regulating valve.

[0042] In this embodiment, the waste heat utilization device includes a waste heat boiler, a crude synthesis gas cooler, a standby boiler and a steam turbine generator set, etc. The steam turbine generator set can supply power to the electrical equipment in the biomass carbon alcohol co-production light synthesis green methanol system through the green power grid.

[0043] In this example, the inlet of the first channel in the waste heat boiler is connected to the high-temperature crude synthesis gas outlet of the dry reforming furnace via the third pipeline, and the outlet of the first channel in the waste heat boiler is connected to the inlet of the first channel in the crude synthesis gas cooler via the fourth pipeline; the outlet of the second channel in the waste heat boiler is connected to the inlet of the steam turbine generator set via the fourteenth pipeline, and the outlet of the steam turbine generator set is connected to the inlet of the second channel in the waste heat boiler via the fifteenth pipeline.

[0044] In this embodiment, the waste heat boiler converts the waste heat of the high-temperature raw synthesis gas at about 1300°C exiting the dry reforming furnace into medium-pressure steam for power generation by the steam turbine generator set; the independent system does not need to supply steam to the outside, and the steam turbine adopts a condensing steam turbine to obtain the maximum power generation; for application scenarios where steam needs to be supplied to the outside, a back-pressure steam turbine can be used to produce low-pressure steam to meet the needs.

[0045] In this example, a dry reforming furnace outlet temperature sensor for collecting the temperature of the crude synthesis gas in the third pipeline is provided on the third pipeline. The dry reforming furnace outlet temperature sensor circuit is connected to the electric control end of the dry reforming oxygen regulating valve and the pyrolysis gas regulating valve to control the opening of the dry reforming oxygen regulating valve and the pyrolysis gas regulating valve based on the crude synthesis gas temperature, thereby realizing closed-loop control of the crude synthesis gas temperature. The pyrolysis gas regulating valve and the dry reforming oxygen regulating valve are linked to form a proportional regulation to meet the amount of oxygen required for the pyrolysis gas heating and the reforming endothermic reaction of tar gas and methane gas, thereby ensuring the reforming result.

[0046] In this embodiment, the inlet of the second channel in the raw synthesis gas cooler is connected to the soft water storage tank, and the outlet of the second channel is connected to the fifteenth pipeline through the sixteenth pipeline equipped with a hot soft water supplement regulating valve. The electric control end circuit of the hot soft water supplement regulating valve is connected to the turbine condensate return flowmeter, and the turbine condensate return flowmeter is installed on the fifteenth pipeline.

[0047] In this example, the raw synthesis gas cooler uses a soft water system to supply water, and the hot soft water produced is partly used to supplement the condensed circulating water recovered by the turbine and returned to the waste heat boiler; if a back pressure turbine system is used, all the hot soft water produced will enter the waste heat boiler to produce steam.

[0048] In this embodiment, the inlet of the standby boiler is connected to the fifteenth pipe via the seventeenth pipe, and the outlet of the standby boiler is connected to the fourteenth pipe via the eighteenth pipe. The standby boiler burner of the standby boiler is connected to the fourth pipe via a pipe equipped with a standby boiler gas regulating valve, so that part of the crude synthesis gas cooled by the waste heat boiler is used as the standby boiler burner gas; the standby boiler burner is also connected to the oxygen generator via the thirteenth pipe equipped with a standby boiler oxygen regulating valve.

[0049] In this example, the electric control end of the standby boiler gas regulating valve is connected to the electric control end of the standby boiler oxygen regulating valve in a circuit so as to adjust the ratio of the raw synthesis gas and oxygen.

[0050] In this embodiment, the backup boiler is used when the power of the whole system cannot be balanced. Part of the raw synthesis gas is drawn out as fuel gas to increase the steam output to meet the need of self-power balance. The backup boiler can use oxygen-enriched combustion or directly use air combustion. In principle, this part of the flue gas is directly discharged. If green carbon dioxide capture is required, a separate one will be set up.

[0051] In this embodiment, the fourth pipeline is connected to the external combustion chamber burner through a pipeline equipped with a crude synthesis gas branch regulating valve, and the electrical control end circuit of the crude synthesis gas branch regulating valve is connected to the external combustion chamber flame temperature sensor, which is used to collect the temperatures of the internal and external combustion chambers of the biomass charcoal-gas cogeneration device.

[0052] like Figure 4 As shown, the light and heavy component separation device in this embodiment includes a main adsorption tower, a light component gas tank A, a light component gas tank B, a heavy component gas tank and an air extraction pump, etc., wherein the bottom of the main adsorption tower is connected to the first channel outlet in the crude synthesis gas cooler in the waste heat utilization device through a separation air inlet valve, an air extraction pump, a crude synthesis gas regulating valve and a fifth pipeline.

[0053] In this embodiment, the bottom interface of the main adsorption tower is connected to the pipeline between the crude synthesis gas regulating valve and the vacuum pump via the heavy component valve, and the pipeline between the vacuum pump and the separation air inlet valve is connected to the heavy component gas tank via the heavy component gas tank regulating valve. The bottom of the main adsorption tower can be connected to the heavy component gas tank via the heavy component valve, the vacuum pump and the heavy component gas tank regulating valve in sequence.

[0054] In this example, the recombinant gas tank is connected to the external combustion chamber burner in the biomass charcoal-gas cogeneration device via the twenty-second pipeline equipped with a gas regulating valve.

[0055] In this embodiment, the top interface of the main adsorption tower is divided into two branches after the light component regulating valve. One branch is provided with a light component air inlet valve A, a light component gas tank A and a light component air outlet valve A in sequence, and the other branch is provided with a light component air inlet valve B, a light component gas tank B and a light component air outlet valve B in sequence. The two branches are connected to the sixth pipeline through a tee.

[0056] like Figure 5 As shown, in this example, the methanol synthesis system includes a synthesis gas compressor unit, a methanol condenser, a synthetic methanol tower and a finished gas cooler, etc. The inlet of the first channel in the methanol condenser is connected to the sixth pipeline equipped with a synthesis gas regulating valve and a synthesis gas compressor unit, and the outlet of the first channel in the methanol condenser is connected to the lower inlet of the methanol synthesis tower through the nineteenth pipeline.

[0057] In this embodiment, the lower inlet of the methanol synthesis tower is connected to the second channel inlet of the methanol condenser through the twentieth pipeline, and the second channel outlet of the methanol condenser is connected to the gas-liquid inlet of the methanol gas-liquid separator through the finished gas cooler.

[0058] In this example, the synthesis gas enters the synthesis gas compressor unit through the synthesis gas regulating valve and is compressed to the process pressure, and is mixed with the circulating synthesis gas pressurized by the circulating synthesis gas booster pump to form the raw gas, which enters the methanol condenser and is preheated to the required inlet temperature of the methanol synthesis tower, enters the lower inlet of the methanol synthesis tower, enters the synthesis tower and passes through the catalyst in the tube-in-tube process, so that part of the raw gas is converted into methanol gas to form finished gas, which is drawn out from the top of the synthesis tower and enters the methanol condenser.

[0059] In this embodiment, the product gas comes out of the methanol synthesis tower, passes through the methanol condenser, is cooled by the raw gas, and the raw gas is preheated at the same time; if the methanol in the product gas is not condensed enough, all the methanol is condensed through the finished gas cooler and transported to the methanol gas-liquid separator, and the liquid methanol is sent to the crude methanol tank.

[0060] In this example, the methanol synthesis tower is of a shell-and-tube structure, with the tube side filled with catalysts and the shell side immersed in phase-changing heat transfer oil. Since methanol synthesis is an exothermic reaction, heat is generated to heat the liquid heat transfer oil in the shell side, causing the heat transfer oil to vaporize and enter the heat transfer oil condenser from the upper end of the heat transfer oil steam pipe. The condensed liquid heat transfer oil enters the container of the heat transfer oil electric heater and is sent back to the shell side of the methanol synthesis tower by the heat transfer oil circulation pump. The heat transfer oil pump and the methanol synthesis tower form a liquid level closed-loop control, thereby ensuring the constant temperature control of the methanol synthesis tower.

[0061] In this embodiment, the liquid outlet of the methanol gas-liquid separator is connected to the crude methanol storage tank via the eighth pipeline, and liquid methanol is stored in the crude methanol storage tank; the gas outlet of the methanol gas-liquid separator is connected to the twenty-second pipeline via the twenty-first pipeline equipped with a purge gas regulating valve, and is connected to the external combustion chamber burner in the biomass charcoal-gas co-production device via the twenty-second pipeline; the gas outlet of the methanol gas-liquid separator is also connected to the sixth pipeline via a pipeline equipped with a circulating synthesis gas booster pump.

[0062] In this example, a certain proportion of purge gas is drawn out above the gas-liquid separator. The proportion of the purge gas drawn out is controlled by the purge gas regulating valve and transported to the pipe of the recombinant gas return carbonization burner for carbonization combustion heating.

[0063] In this embodiment, the crude methanol storage tank is connected to the methanol internal combustion engine power generation group via the ninth pipeline to provide fuel for the methanol internal combustion engine power generation group. The methanol internal combustion engine power generation group generates electricity to supply power to the electrical equipment in the biomass carbon alcohol co-production light synthesis green methanol system through the green power grid.

[0064] In this example, after the biomass raw materials enter the biomass charcoal-gas cogeneration device, the recombinant gas and purge gas produced by the subsequent units are burned by the external combustion chamber burner, and part of the crude synthesis gas is added to make up for the shortfall. The amount of crude synthesis gas added is automatically controlled by the external combustion chamber flame temperature sensor and the closed-loop control of the crude synthesis gas path regulating valve, maintaining the stable production of the entire charcoal-gas cogeneration and producing stable pyrolysis gas.

[0065] In this embodiment, an air separation oxygen generator is used to separate the oxygen in advance, and a variable frequency circulating flue gas exhaust fan and regulating valve, oxygen regulating valve, gas regulating valve, etc. are used to form a closed-loop control with the external combustion chamber flame temperature sensor to form nitrogen-free combustion, which is convenient for increasing the carbonization temperature to produce high-quality biochar without generating excessive nitrogen oxides. At the same time, it can also simplify the process flow for green carbon dioxide capture of the net exhaust flue gas, reduce energy consumption, and achieve a near-zero emission process.

[0066] The method for co-producing light synthetic green methanol from biomass charcoal and alcohol in this embodiment specifically comprises the following steps: S1. Sending the biomass raw materials into the biomass charcoal gas cogeneration device to generate biochar and pyrolysis gas; S2, connecting the pyrolysis gas and oxygen to the dry reforming burner, and sending them into the dry reforming furnace through the dry reforming burner, so that the oxygen and hydrogen in the pyrolysis gas burn to produce water vapor, and the tar gas and methane in the pyrolysis gas react with the water vapor to produce hydrogen and carbon monoxide, forming a high-temperature crude synthesis gas; S3, sending the high-temperature crude synthesis gas to a waste heat utilization device to form a low-temperature crude synthesis gas; S4, sending the low-temperature crude synthesis gas to a light-heavy component separation device to separate and purify the low-temperature crude synthesis gas to form a purified synthesis gas whose carbon-hydrogen ratio meets preset conditions; S5, pressurizing the purified synthesis gas to form a synthesis raw gas, sending it to a methanol synthesis system, partially converting it into methanol, and condensing it to form a gas-liquid mixture containing liquid methanol; S6, sending the gas-liquid mixture containing liquid methanol into a methanol gas-liquid separator to separate the liquid methanol; S6. Send liquid methanol into the crude methanol storage tank.

[0067] In this embodiment, step S4 specifically includes: During the period when light component gas is produced, and at this time, light component gas tank A is emptied and light component gas tank B is full, the crude synthesis gas enters the light and heavy component separation device through the crude synthesis gas regulating valve. At this time, the heavy component valve, the heavy component regulating valve, the light component outlet valve A, and the light component inlet valve B are all closed, and the separation regulating valve, the light component regulating valve, the light component inlet valve A, and the light component outlet valve B are all opened. The crude synthesis gas is pressurized through the crude synthesis gas regulating valve, the vacuum pump, and the separation regulating valve and enters the main adsorption tower. The gas passing through the main adsorption tower within the preset time period is sent to the light component gas tank A through the light component inlet valve A as purified synthesis gas.

[0068] During the period of producing heavy component gas, the heavy component valve and the heavy component regulating valve are opened, the crude synthesis gas regulating valve, the separation regulating valve and the light component regulating valve are closed, and a vacuum pump is used to draw all the gas remaining in the main adsorption tower after a preset time period into the heavy component gas tank; after completion, all valves are switched to the state of producing light component gas for the light component gas tank B, and the next separation cycle is entered.

[0069] In this embodiment, when light component gas tank A produces light component gas, light component gas tank B provides purified synthesis gas for the subsequent process. When light component gas tank B produces light component gas, light component gas tank A provides purified synthesis gas for the subsequent process. Light component gas tanks A and B operate alternately to ensure a stable supply of synthesis gas in the subsequent process.

[0070] The present invention is not limited to the above-mentioned embodiments. It should be pointed out that those skilled in the art can replace or modify one or some features based on the present invention without creative work, and these replacements or modifications are all within the protection scope of the present invention.

Claims

1. A method for co-producing light synthetic green methanol from biomass carbon alcohol, characterized in that: include: The biomass raw materials are fed into a biomass charcoal-gas cogeneration device to generate biochar and pyrolysis gas; A part of the pyrolysis gas is returned to the burner on the carbon-gas cogeneration device through the high-temperature booster fan and the regulating valve to be used as fuel to provide heat for carbonization combustion; The other part of the pyrolysis gas is connected to the dry reforming burner through the high-temperature booster fan and the regulating valve and oxygen, and then sent to the dry reforming furnace by the dry reforming burner, so that the oxygen and hydrogen in the pyrolysis gas burn to produce water vapor, and the tar gas and methane in the pyrolysis gas react with the water vapor to produce hydrogen and carbon monoxide, forming a high-temperature crude synthesis gas; The high-temperature crude synthesis gas is sent to a waste heat utilization device to form a low-temperature crude synthesis gas; The low-temperature crude synthesis gas is sent to a light-heavy component separation device to separate and purify the low-temperature crude synthesis gas to form a purified synthesis gas whose carbon-hydrogen ratio meets preset conditions; The purified synthesis gas is pressurized to form a synthesis raw gas, which is then fed into a methanol synthesis system, partially converted into methanol, and 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; sending liquid methanol into a crude methanol storage tank; The light and heavy component separation device separates and purifies the low-temperature raw synthesis gas, including: The low-temperature raw synthesis gas is pressurized and sent to the main adsorption tower, and the gas that passes through the main adsorption tower within a preset time is sent to the light component gas tank as purified synthesis gas; The gas retained in the main adsorption tower after a preset time is pumped to the recombinant gas tank.

2. The method for co-producing light synthetic green methanol from biomass charcoal and alcohol according to claim 1, characterized in that: Part of the flue gas produced by the external combustion chamber burner in the biomass charcoal-gas cogeneration device is mixed with high-purity oxygen and then sent back to the external combustion chamber burner for combustion assistance.

3. The method for co-producing light synthetic green methanol from biomass charcoal and alcohol according to claim 1, characterized in that: The waste heat utilization device absorbs the heat of the high-temperature raw synthesis gas through the waste heat boiler, heats the soft water to form water vapor with a certain pressure; and sends the water vapor with a certain pressure to the steam turbine generator set to drive the steam turbine generator set to generate electricity.

4. The method for co-producing light synthetic green methanol from biomass charcoal and alcohol according to claim 1, characterized in that: The recombinant gas is extracted from the recombinant gas tank and returned to the burner on the carbon-gas cogeneration device to be used as fuel to provide heat for carbonization combustion.

5. The method for co-producing light synthetic green methanol from biomass charcoal and alcohol according to claim 4, characterized in that: The recombinant gas comes out of the recombinant gas tank. When the green power grid is insufficient, the gas internal combustion engine generator set generates electricity to balance the electricity required by the entire system of the equipment. At this time, the proportion of pyrolysis gas returning to the carbon-gas cogeneration device through the high-temperature booster fan and the regulating valve is increased to ensure the needs of biomass carbon-gas cogeneration heating.

6. The method for co-producing light synthetic green methanol from biomass charcoal and alcohol according to claim 1, characterized in that: The light component gas tank includes a light component gas tank A and a light component gas tank B; The low-temperature crude synthesis gas is pressurized and sent to the main adsorption tower. The gas that passes through the main adsorption tower within a preset time is sent to the light component gas tank A or B as purified synthesis gas. At this time, the purified synthesis gas in the other light component gas tank is pressurized to form synthesis raw gas and sent to the methanol synthesis system; The gas retained in the main adsorption tower after a preset time is pumped to the recombinant gas tank.

7. A biomass carbon alcohol co-production light synthetic green methanol system, characterized in that: include: Biomass charcoal and gas cogeneration device, used to process biomass raw materials into biochar and pyrolysis gas; A dry reforming furnace, wherein the dry reforming burner is connected to the biomass charcoal gas cogeneration device via a first pipeline and is also connected to the oxygen generator via a second pipeline, for burning oxygen with hydrogen in the pyrolysis gas to produce water vapor, and reacting tar gas and methane in the pyrolysis gas with the water vapor to produce hydrogen and carbon monoxide, thereby forming a high-temperature crude synthesis gas; A waste heat utilization device, connected to the dry reforming furnace via a third pipeline, for reducing the temperature of the high-temperature crude synthesis gas to form a low-temperature crude synthesis gas; A light-heavy component separation device, connected to the waste heat utilization device via a fifth pipeline, for separating and purifying the low-temperature raw synthesis gas to form a purified synthesis gas with a carbon-to-hydrogen ratio that meets a preset condition; A methanol synthesis system is connected to the light-heavy component separation device via a sixth pipeline equipped with a synthesis gas compressor unit, and is used to convert part of the synthesis raw gas formed by pressurizing the purified synthesis gas into methanol, and condense it 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 crude methanol storage tank, connected to the methanol gas-liquid separator via an eighth pipeline, for storing liquid methanol; The light and heavy component separation device comprises: The main adsorption tower, whose bottom is connected to the air inlet of the light-heavy component separation device through a separation air inlet valve and an air pump; its bottom is connected to the heavy component gas tank through a heavy component valve and an air pump; the main adsorption tower is filled with an adsorbent that hinders the passage of gas molecules, and the heavier the gas molecule, the slower the gas passes through; hydrogen molecules are the lightest in the crude synthesis gas, followed by carbon monoxide, so hydrogen has the fastest passing rate, followed by carbon monoxide; when the ratio of hydrogen to carbon monoxide in the light component tank reaches 2.1-2.2:1, it is immediately cut off; the gas remaining in the main adsorption tower is mainly carbon dioxide and impurity gases, such as sulfur dioxide, etc.; then the valve group is switched to pump all the gas in the main adsorption tower into the heavy component tank, and then enter the next separation cycle; The light component gas tank has an air inlet connected to the top of the main adsorption tower via a light component air inlet valve, and a light component gas tank air outlet connected to the air outlet of the light-heavy component separation device via a light component air outlet valve.

8. The biomass carbon alcohol co-production light synthetic green methanol system according to claim 7 is characterized in that: Also includes: A carbon dioxide capture module is connected to the external combustion chamber in the biomass charcoal and gas cogeneration device through a tenth pipeline, and is used to capture carbon dioxide in the flue gas generated by the burners in the internal and external combustion chambers of the biomass charcoal and gas cogeneration device; The eleventh pipeline has one end connected to the flue gas exhaust pipe of the external combustion chamber in the biomass charcoal gas co-production device, and the other end connected to the burner of the external combustion chamber. The eleventh pipeline is connected to the oxygen generator via the twelfth pipeline, which is used to provide high-concentration oxygen to the gas burner to prepare oxygen-enriched flue gas. The oxygen-enriched concentration is controlled by proportional regulation through the regulating valve on the eleventh pipeline and the regulating valve on the twelfth pipeline.

9. The biomass carbon alcohol co-production light synthetic green methanol system according to claim 7, characterized in that: The waste heat utilization device comprises: A waste heat boiler, wherein the first channel inlet is connected to the dry reforming furnace via the third pipeline; The inlet of the steam turbine generator set is connected to the outlet of the second channel in the waste heat boiler via the fourteenth pipeline, and the outlet of the steam turbine generator set is connected to the inlet of the second channel in the waste heat boiler via the fifteenth pipeline.

10. The biomass carbon alcohol co-production light synthetic green methanol system according to claim 9, characterized in that: The waste heat utilization device further comprises: A raw syngas cooler, wherein the inlet of the first channel in the raw syngas cooler is connected to the outlet of the first channel in the waste heat boiler via a fourth pipeline; the inlet of the second channel in the raw syngas cooler is connected to the soft water storage tank, and the outlet of the second channel is connected to the fifteenth pipeline via a sixteenth pipeline equipped with a hot soft water supplement regulating valve; The electric control end circuit of the hot soft water supplement regulating valve is connected to the steam turbine condensate return water flow meter, and the steam turbine condensate return water flow meter is installed on the fifteenth pipeline.

11. The biomass carbon-alcohol co-production light synthetic green methanol system according to claim 7, characterized in that: The light component gas tank includes a light component gas tank A and a light component gas tank B; The air inlet of the light component gas tank A is connected to the top of the main adsorption tower through the light component air inlet valve A, and the air outlet of the light component gas tank A is connected to the air outlet of the light and heavy component separation device through the light component air outlet valve A; The air inlet of the light component gas tank B is connected to the top of the main adsorption tower through the light component air inlet valve B, and the air outlet of the light component gas tank B is connected to the air outlet of the light-heavy component separation device through the light component air outlet valve B.

12. The biomass carbon alcohol co-production light synthetic green methanol system according to claim 7, characterized in that: The methanol synthesis system comprises: A methanol condenser, wherein the first channel inlet is connected to the sixth pipeline; A methanol synthesis tower, whose lower inlet is connected to the first channel outlet in the methanol condenser via a nineteenth pipeline, and whose upper outlet is connected to the second channel inlet in the methanol condenser via a twentieth pipeline; A finished gas cooler, whose inlet is connected to the outlet of the second channel in the methanol condenser, and whose outlet is connected to the methanol gas-liquid separator.

13. The biomass carbon-alcohol co-production light synthetic green methanol system according to claim 7, characterized in that: The methanol gas-liquid separator is connected to the crude synthesis gas through the twenty-first pipeline to enter the light and heavy component separation system to recover the effective gas hydrogen and carbon monoxide of the purge gas.

14. A light and heavy component separation device, characterized in that ,include: The main adsorption tower, the bottom of which is connected to the air inlet of the light and heavy component separation device through a separation air inlet valve and an air pump; The bottom is connected to the recombinant gas tank via the recombinant valve and the air pump; The light component gas tank has an air inlet connected to the top of the main adsorption tower via a light component air inlet valve, and a light component gas tank air outlet connected to the air outlet of the light-heavy component separation device via a light component air outlet valve.

15. The light and heavy component separation device according to claim 14, characterized in that: The light component gas tank includes a light component gas tank A and a light component gas tank B; The air inlet of the light component gas tank A is connected to the top of the main adsorption tower through the light component air inlet valve A, and the air outlet of the light component gas tank A is connected to the air outlet of the light and heavy component separation device through the light component air outlet valve A; The air inlet of the light component gas tank B is connected to the top of the main adsorption tower through the light component air inlet valve B, and the air outlet of the light component gas tank B is connected to the air outlet of the light-heavy component separation device through the light component air outlet valve B.

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