A green methanol and green ammonia co-production system and method based on a conventional coal-to-methanol plant and a high-temperature fuel cell electrolyzer

Abstract

The present application relates to a kind of green alcohol and green ammonia co-production system and method based on traditional coal methanol device and high temperature fuel cell electrolytic cell, belong to fuel cell technical field.The green alcohol and green ammonia co-production system includes: raw material pretreatment and vaporization module, coal gas purification module, methanol synthesis and gas-liquid separation module, SOFC power generation and CO2 enrichment module, SOEC electrolysis module, green alcohol synthesis module and green ammonia synthesis module.The green alcohol and green ammonia co-production system is through "electric-chemical-carbon" synergic cycle, simultaneously solves renewable energy consumption and high carbon chemical decarburization two big problems, realizes green alcohol and green ammonia efficient co-production.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a system and method for the co-production of green alcohol and green ammonia based on a conventional coal-to-methanol plant and a high-temperature fuel cell electrolyzer. Background Technology

[0002] Currently, the installed capacity of global renewable energy (wind power, photovoltaics, etc.) continues to surge, and costs are constantly decreasing with technological iterations, making it a core driving force for energy structure transformation. However, the inherent intermittency, volatility, and randomness of renewable energy put enormous pressure on grid frequency regulation and peak shaving, easily causing problems such as voltage fluctuations and frequency deviations, severely restricting its large-scale grid connection and consumption. As a mainstream peak shaving solution, battery energy storage is limited by capacity density, cycle life, and cost, while pumped hydro storage depends on specific geographical conditions, making it difficult to achieve full-scenario, large-scale adaptation. Against this backdrop, "on-site conversion of renewable energy into high-value-added chemicals" has become a key path to solve the consumption problem, and "power-to-gas" and "power-to-liquid" technology routes have attracted much attention. Among them, the co-production model of green alcohol (green methanol) and green ammonia, with its multiple application values ​​of products and system synergy advantages, is gradually becoming a hot topic in research and industrial layout.

[0003] Both green alcohol and green ammonia are highly promising renewable energy storage media and carbon-free / low-carbon products, and their co-production possesses natural synergy. Methanol, as a multi-purpose chemical and clean fuel, boasts advantages such as convenient storage and transportation, high energy density, and compatibility with existing fuel supply systems. It is widely used in chemical synthesis, transportation, fuel cells, and other fields, serving as a crucial medium connecting the energy and chemical industries. Green ammonia, with its zero-carbon combustion characteristics (combustion product is only water), safe storage and transportation (liquefiable under normal pressure, reusable from existing ammonia storage and transportation infrastructure), and diverse application scenarios (fertilizer feedstock, gas turbine power generation, hydrogen carrier, etc.), has become a core option for solving the long-term energy storage and cross-sectoral consumption of renewable energy. Single-product preparation is susceptible to market fluctuations and resource constraints, while the co-production of green alcohol and green ammonia can flexibly allocate core raw materials (green hydrogen, CO2, nitrogen), balancing product structure and market demand, while simultaneously enhancing the system's adaptability to renewable energy fluctuations and maximizing energy utilization efficiency.

[0004] Solid oxide fuel cells (SOFCs) and solid oxide electrolyzers (SOECs) are the core technologies supporting this cogeneration model and key supports for promoting decarbonization in the energy and chemical industry and the efficient utilization of renewable energy. SOFCs have advantages such as wide fuel applicability, high power generation efficiency (up to 50%~60%, combined cycle efficiency exceeding 80%), and low pollutant emissions. They can not only directly generate electricity using products such as methanol and ammonia, but also couple with low-calorific-value tail gases (containing CO, H2, CH4, etc.) from chemical plants such as coal-to-methanol (CTM) to improve the overall system efficiency through energy cascade utilization, while simultaneously achieving the enrichment and recovery of CO2 in the tail gas. SOECs, relying on their reversible operating characteristics, can consume redundant electricity during periods of surplus green electricity or grid off-peak periods to electrolyze steam (H2O) and carbon dioxide (CO2) into H2, CO, and other value-added gases, or directly achieve CO2 hydrogenation conversion. They not only undertake the function of power peak shaving, but also provide core raw materials for the synthesis of green alcohols and green ammonia, forming a closed-loop chain of "green electricity-chemical raw materials-energy storage products".

[0005] In recent years, driven by the global energy transition and the "dual carbon" goal, the demand for upgrading traditional high-emission chemical processes and efficiently converting renewable energy has overlapped. The use of SOFC / SOEC technology coupled with renewable energy to produce green alcohols and green ammonia, gradually replacing traditional fossil-based processes (coal-to-methanol and Haber process ammonia synthesis), has become a new direction for industry research and practice. Traditional CTM (coal-to-methanol) industries have extremely high carbon emission intensity; producing 1 ton of methanol can result in 1.8 to 2.5 tons of carbon emissions. Traditional Haber process ammonia synthesis relies on fossil fuels for hydrogen production, with a carbon emission intensity of approximately 1.9 tons of CO2 per ton of ammonia, consuming about 2% of the world's total energy. Against this backdrop, the co-production model of renewable energy coupled with SOFC / SOEC can provide a decarbonization solution for the traditional chemical industry, solve the problem of renewable energy consumption, and achieve synergistic benefits across "energy-chemicals-environmental protection."

[0006] Currently, existing technologies for preparing single-product green alcohols and green ammonias both have significant limitations. The mainstream approaches for single-product green alcohol preparation fall into two categories: one is to electrolyze water to produce green hydrogen, which is then combined with CO2 to synthesize methanol. However, this method is affected by the volatility of renewable energy sources, resulting in unstable green hydrogen supply. Furthermore, the fixed asset investment in electrolysis and synthesis units is large, leading to weak system resilience. The second approach involves electrolysis to produce hydrogen coupled with a traditional CTM system. While this can reduce some fossil fuel consumption, a large amount of N2 byproduct cannot be efficiently utilized. Single-product green ammonia preparation faces challenges such as high green hydrogen costs, high energy consumption for nitrogen separation, and poor coupling between electrolysis and synthesis units. Additionally, the product's application scenarios are relatively concentrated, making it susceptible to agricultural market cycles. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a system and method for the co-production of green alcohol and green ammonia based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a green alcohol and green ammonia co-production system based on a traditional coal-to-methanol device and a high-temperature fuel cell electrolyzer, comprising: a raw material pretreatment and vaporization module, a coal gas purification module, a methanol synthesis and gas-liquid separation module, an SOFC (solid oxide fuel cell) power generation and CO2 enrichment module, an SOEC (solid oxide electrolyzer) electrolysis module, a green alcohol synthesis module, and a green ammonia synthesis module. The raw material pretreatment and vaporization module is used to generate crude coal gas; The gas purification module is used to purify crude coal gas and generate purified gas. The methanol synthesis and gas-liquid separation module includes a methanol synthesis unit, a gas-liquid separator, and a purification unit. The purified gas is fed to the methanol synthesis unit to undergo a synthesis reaction to obtain a gas-vapor mixture; the gas-vapor mixture is condensed and cooled before entering a gas-liquid separator to separate liquid and gaseous products; the gaseous products include recycle gas and purge gas; the purge gas is fed to a purification unit to be purified to obtain hydrogen-rich permeate gas and non-permeate gas; the recycle gas and hydrogen-rich permeate gas are returned to the methanol synthesis unit to continue participating in the synthesis reaction. The SOFC power generation and CO2 enrichment module includes an SOFC stack and a CO2 / N2 separation unit. The non-permeable gas is fed to the SOFC anode in the SOFC stack to participate in the electrochemical oxidation reaction of the fuel to obtain a CO2 / H2O mixed gas; the CO2 / H2O mixed gas is condensed and dehydrated and then enters the CO2 / N2 separation unit to separate CO2 and N2; The SOEC electrolysis module includes an SOEC electrolysis cell; The CO2 separated by the CO2 / N2 separation unit is sent to the SOEC electrolytic cell to undergo CO2 / H2O co-electrolysis to obtain CO and H2; The CO2 separated by the CO2 / N2 separation unit and / or the CO and H2 obtained by co-electrolysis of CO2 / H2O are transported to the chloroethanol synthesis module to synthesize methanol. The N2 separated by the CO2 / N2 separation unit and the H2 obtained by co-electrolysis of CO2 / H2O are transported to the green ammonia synthesis module to synthesize ammonia.

[0009] As a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, the methanol synthesis and gas-liquid separation module further includes a gas compression device; And / or, the SOFC power generation and CO2 enrichment module further includes a gas turbine unit, in which the SOFC cathode exhaust in the SOFC stack enters the gas turbine unit for expansion and work, converting thermal energy into mechanical energy.

[0010] As a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, the SOEC electrolysis module further includes a renewable energy power generation unit for converting renewable energy into electrical energy and using it as the power source for the SOEC electrolyzer.

[0011] As a preferred embodiment of the chlorophyll and chloroammonia co-production system of the present invention, the chlorophyll synthesis module includes a chlorophyll synthesis reactor and a distillation unit.

[0012] In a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, the CO2 and / or CO and H2 are fed to the green alcohol synthesis reactor to undergo a synthesis reaction to obtain crude methanol, and the crude methanol is separated and purified by a distillation unit to obtain methanol.

[0013] As a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, the green ammonia synthesis module includes a mixer, a plasma-coupled electrochemical catalytic ammonia synthesis reaction device, and an ammonia separation unit.

[0014] In a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, N2 and H2 are mixed by a mixer to obtain N2 / H2 reaction mixture gas; the N2 / H2 reaction mixture gas enters a plasma-coupled electrochemical catalytic ammonia synthesis reactor to react and obtain a mixture gas of N2, H2 and NH3; the mixture gas enters an ammonia separation unit for condensation and liquefaction to obtain liquid NH3.

[0015] As a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, the raw material pretreatment and gasification module includes a grinding mill, a high-pressure coal slurry pump and a gasifier. Raw coal is ground into pulverized coal by a coal mill. The pulverized coal is mixed with water to obtain coal-water slurry. The coal-water slurry is pressurized to the operating pressure required for gasification by a high-pressure coal slurry pump and then pumped into a gasifier to undergo a gasification reaction to obtain crude coal gas.

[0016] As a preferred embodiment of the green alcohol and green ammonia co-production system of the present invention, the gas purification module includes a heat exchanger, a dust removal unit and a low-temperature methanol washing unit. The crude coal gas is gradually cooled by a heat exchanger and then enters a dust removal unit to remove dust and water-soluble impurities. It then enters a low-temperature methanol washing unit to remove acidic gases and obtain purified gas.

[0017] Secondly, the present invention provides a method for co-producing green alcohol and green ammonia based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer, using the aforementioned green alcohol and green ammonia co-production system.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The co-production model of green alcohol and green ammonia can effectively compensate for the shortcomings of a single product pathway through the sharing and synergy of core raw materials and equipment. This invention uses green alcohol and green ammonia as dual energy storage and carbon sequestration media to construct an integrated system of "renewable energy - SOFC / SOEC - traditional chemical industry upgrading - zero-carbon product output". This co-production system for green alcohol and green ammonia relies on SOFC to treat the non-permeable gas from the CTM unit, achieving CO2 enrichment and energy recovery from the tail gas. The enriched CO2 serves as the carbon source for green alcohol synthesis. SOEC utilizes surplus green electricity to electrolyze water to produce green hydrogen. Part of the green hydrogen is combined with the recovered CO2 to synthesize green alcohol, and the remaining green hydrogen is combined with nitrogen, a byproduct of the CTM unit, to synthesize green ammonia. The waste heat generated by SOFC power generation can supply the CTM unit, the methanol / ammonia synthesis reactor, and the air separation unit, achieving cascaded energy utilization. During system operation, the product ratio of green alcohol and green ammonia can be dynamically adjusted according to the green electricity supply intensity, CO2 recovery amount, and market demand. During peak grid periods, SOFC power generation supplements the energy supply, while SOEC energy storage and conversion are used during off-peak periods, achieving on-site consumption and efficient utilization of electricity and carbon resources, ultimately achieving the goal of zero carbon emissions and energy consumption reduction.

[0019] This invention constructs a zero-carbon integrated system centered on a reversible solid oxide battery (SOFC / SOEC), coupling renewable energy power generation and coal chemical upgrading to achieve flexible co-production of green alcohol and green ammonia. Through a synergistic "electricity-chemical-carbon" cycle, it simultaneously addresses two major challenges: renewable energy consumption and high-carbon chemical decarbonization. The system utilizes SOEC to absorb fluctuating green electricity, electrolyzing water or co-electrolyzing it to produce green hydrogen / syngas. Simultaneously, SOFC efficiently processes off-gas from coal-to-methanol production, improving power generation efficiency and enriching CO2 in situ as a carbon source. By sharing green hydrogen and recovering CO2 and nitrogen, the system can flexibly adjust the alcohol and ammonia production ratio to adapt to market and grid demands, forming a multi-faceted synergy of power peak shaving, carbon recycling, and maximizing product value, ultimately achieving zero-carbon emissions from the chemical process and efficient full-chain consumption of renewable energy.

[0020] Compared to traditional methanol production systems using coal-water slurry gasifiers, the green alcohol and green ammonia co-production system of this invention replaces the air separation system with an SOEC electrolysis module. This module powers the coal-water slurry gasifier while the green hydrogen produced by electrolysis is not only a core raw material for green alcohol synthesis but also a key component for green ammonia synthesis. The remaining green hydrogen can be co-produced with nitrogen, a byproduct of the gasifier, to produce green ammonia. Renewable electricity is converted into green hydrogen via the SOEC electrolysis module and fixed into the green alcohol and green ammonia products. This eliminates the need for a separate coal-water slurry gasifier, reducing coal consumption and air separation system energy consumption, significantly improving system economy, and strengthening the zero-carbon nature of the co-production system through green electricity utilization. Attached Figure Description

[0021] The embodiments of this invention are not limited to the drawings described below, which are only some embodiments of this invention. Those skilled in the art can obtain drawings of other embodiments based on the content of this invention.

[0022] Figure 1 This is a schematic diagram of the coupling method between SOFC / SOEC and renewable energy and coal-to-methanol in the green alcohol and green ammonia co-production system of the present invention; Figure 2 This is a process flow diagram of a green alcohol and green ammonia co-production system according to one embodiment of the present invention. Detailed Implementation

[0023] To better illustrate the purpose, technical solution, and advantages of this invention, the following detailed description, in conjunction with specific embodiments, aims to explain the content of this invention in detail, rather than to limit it. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0024] <General Definition> The term "green methanol" refers to methanol synthesized by catalysis using "green hydrogen" produced from renewable energy sources and carbon dioxide obtained from biomass or direct air capture as raw materials, or produced through sustainable biomass gasification / fermentation routes, with zero or near-zero greenhouse gas emissions throughout its entire life cycle.

[0025] The term "green ammonia" refers to ammonia produced entirely using renewable energy to electrolyze water to produce hydrogen, which is then catalytically synthesized with nitrogen, an industrial byproduct or separated from the air, without generating greenhouse gas emissions throughout the entire process.

[0026] The term "SOFC" refers to a solid oxide fuel cell.

[0027] The term "SOEC" refers to a solid oxide electrolysis cell.

[0028] The term "CTM" refers to coal-to-methanol.

[0029] A green alcohol and green ammonia co-production system based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer includes: a raw material pretreatment and vaporization module, a coal gas purification module, a methanol synthesis and gas-liquid separation module, an SOFC power generation and CO2 enrichment module, an SOEC electrolysis module, a green alcohol synthesis module, and a green ammonia synthesis module. The raw material pretreatment and vaporization module is used to generate crude coal gas; The gas purification module is used to purify crude coal gas and generate purified gas. The methanol synthesis and gas-liquid separation module includes a methanol synthesis unit, a gas-liquid separator, and a purification unit. The purified gas is fed to the methanol synthesis unit to undergo a synthesis reaction to obtain a gas-vapor mixture; the gas-vapor mixture is condensed and cooled before entering a gas-liquid separator to separate liquid and gaseous products; the gaseous products include recycle gas and purge gas; the purge gas is fed to a purification unit to be purified to obtain hydrogen-rich permeate gas and non-permeate gas; the recycle gas and hydrogen-rich permeate gas are returned to the methanol synthesis unit to continue participating in the synthesis reaction. The SOFC power generation and CO2 enrichment module includes an SOFC stack and a CO2 / N2 separation unit. The non-permeable gas is fed to the SOFC anode in the SOFC stack to participate in the electrochemical oxidation reaction of the fuel to obtain a CO2 / H2O mixed gas; the CO2 / H2O mixed gas is condensed and dehydrated and then enters the CO2 / N2 separation unit to separate CO2 and N2; The SOEC electrolysis module includes an SOEC electrolysis cell; The CO2 separated by the CO2 / N2 separation unit is sent to the SOEC electrolytic cell to undergo CO2 / H2O co-electrolysis to obtain CO and H2; The CO2 separated by the CO2 / N2 separation unit and / or the CO and H2 obtained by co-electrolysis of CO2 / H2O are transported to the chloroethanol synthesis module to synthesize methanol. The N2 separated by the CO2 / N2 separation unit and the H2 obtained by co-electrolysis of CO2 / H2O are transported to the green ammonia synthesis module to synthesize ammonia.

[0030] The co-production model of green alcohol and green ammonia can effectively compensate for the shortcomings of a single product pathway through the sharing and synergy of core raw materials and equipment. This invention uses green alcohol and green ammonia as dual energy storage and carbon sequestration media to construct an integrated system of "renewable energy - SOFC / SOEC - traditional chemical industry upgrading - zero-carbon product output" (e.g., Figure 1(As shown). This green alcohol and green ammonia co-production system relies on SOFC to treat the non-permeable gas of the CTM unit, achieving CO2 enrichment and energy recovery from the tail gas. The enriched CO2 serves as the carbon source for green alcohol synthesis. SOEC utilizes surplus green electricity to electrolyze water to produce green hydrogen. Part of the green hydrogen is combined with the recovered CO2 to synthesize green alcohol, and the remaining green hydrogen is combined with nitrogen, a byproduct of the CTM unit, to synthesize green ammonia. The waste heat generated by SOFC power generation can supply the CTM unit, the methanol / ammonia synthesis reactor, and the air separation unit, achieving energy cascade utilization. During system operation, the product ratio of green alcohol and green ammonia can be dynamically adjusted according to the green electricity supply intensity, CO2 recovery amount, and market demand. During peak grid periods, SOFC power generation supplements the energy supply, while SOEC energy storage and conversion are used during off-peak periods, achieving on-site consumption and efficient utilization of electricity and carbon resources, ultimately achieving the goal of zero carbon emissions and energy consumption reduction.

[0031] This invention constructs a zero-carbon integrated system centered on a reversible solid oxide battery (SOFC / SOEC), coupling renewable energy power generation and coal chemical upgrading to achieve flexible co-production of green alcohol and green ammonia. Through a synergistic "electricity-chemical-carbon" cycle, it simultaneously addresses two major challenges: renewable energy consumption and high-carbon chemical decarbonization. The system utilizes SOEC to absorb fluctuating green electricity, electrolyzing water or co-electrolyzing it to produce green hydrogen / syngas. Simultaneously, SOFC efficiently processes off-gas from coal-to-methanol production, improving power generation efficiency and enriching CO2 in situ as a carbon source. By sharing green hydrogen and recovering CO2 and nitrogen, the system can flexibly adjust the alcohol and ammonia production ratio to adapt to market and grid demands, forming a multi-faceted synergy of power peak shaving, carbon recycling, and maximizing product value, ultimately achieving zero-carbon emissions from the chemical process and efficient full-chain consumption of renewable energy.

[0032] Compared to traditional methanol production systems using coal-water slurry gasifiers, the green alcohol and green ammonia co-production system of this invention replaces the air separation system with an SOEC electrolysis module. This module powers the coal-water slurry gasifier while the green hydrogen produced by electrolysis is not only a core raw material for green alcohol synthesis but also a key component for green ammonia synthesis. The remaining green hydrogen can be co-produced with nitrogen, a byproduct of the gasifier, to produce green ammonia. Renewable electricity is converted into green hydrogen via the SOEC electrolysis module and fixed into the green alcohol and green ammonia products. This eliminates the need for a separate coal-water slurry gasifier, reducing coal consumption and air separation system energy consumption, significantly improving system economy, and strengthening the zero-carbon nature of the co-production system through green electricity utilization.

[0033] <Raw Material Pretreatment and Vaporization Module> The raw material pretreatment and gasification module includes a coal mill, a high-pressure coal slurry pump, and a gasifier.

[0034] Raw material changes: raw coal (solid) → coal-water slurry (liquid-solid mixture) → crude coal gas (high-temperature gaseous mixture).

[0035] 1.1 Coal mill Raw coal is ground and crushed to a suitable particle size by a coal mill. The purpose is to increase the contact area between the raw coal and water, preparing for the subsequent preparation of coal-water slurry and gasification reaction. The fineness of the coal directly affects the concentration of coal-water slurry and gasification efficiency, and is a prerequisite for ensuring uniform and stable subsequent reactions.

[0036] 1.2 High-pressure coal slurry pump The ground coal powder is mixed with water in a certain proportion to form a coal-water slurry. The coal-water slurry is pressurized by a high-pressure coal slurry pump to the operating pressure required for gasification (on the order of several MPa) and then pumped to the inlet of the gasifier. The function of the high-pressure coal slurry pump is to overcome the high-pressure environment inside the gasifier and ensure that the material can be fed continuously and stably.

[0037] 1.3 Gasification furnace In the gasifier, coal-water slurry undergoes a gasification reaction under oxygen-deficient (oxygen content is lower than the theoretical amount for complete combustion) and high temperature and pressure conditions. The carbon and hydrogen in the coal undergo a series of complex reactions such as incomplete oxidation and water-gas conversion with a small amount of oxygen and water vapor, which transforms solid coal into high-temperature crude coal gas (outlet temperature of about 1300℃) with CO and H2 as the main effective components and CH4, CO2, H2O (steam), H2S and a small amount of ash.

[0038] In some embodiments, the gasifier is preferably a multi-nozzle opposed coal-water slurry gasifier.

[0039] In traditional coal-to-methanol (CTM) systems, two or more gasifiers are typically configured to ensure an ample supply of carbon sources. However, in the green methanol and green ammonia co-production system based on a traditional coal-to-methanol unit and a high-temperature fuel cell electrolyzer, the SOEC electrolysis hydrogen production module can provide a large amount of green hydrogen (H2), significantly reducing the demand for H2 from coal-to-syngas. Therefore, only one gasifier is required, which reduces coal consumption and the scale of the air separation unit while maintaining a stable source of CO carbon and by-product N2, effectively offsetting the impact of renewable energy volatility on the continuous production of the system.

[0040] <Gas Purification Module> The gas purification module includes a heat exchanger, a dust removal unit, and a low-temperature methanol cleaning unit.

[0041] Raw material change: high-temperature crude coal gas containing impurities → low-temperature clean purified gas (effective gas CO / H2, about 5.5MPa).

[0042] If impurities such as H2S, dust, and ammonia nitrogen carried in the crude coal gas are not removed, they will lead to catalyst poisoning, pipeline blockage, and product quality degradation. Therefore, purification is an indispensable and critical step in the entire process.

[0043] The gas purification module completes the staged purification of the gas through the following units in sequence: 2.1 Heat Exchanger The high-temperature crude gas, approximately 1300℃, exiting the gasifier, is first cooled gradually through a series of heat exchangers. The high-grade heat recovered from these heat exchangers can be used to preheat boiler feedwater, generate steam, or provide heat for other process stages, achieving cascaded energy utilization and avoiding the ineffective waste of high-temperature heat. After cooling, the water vapor and some impurities entrained in the crude gas begin to condense, creating conditions for subsequent solid-liquid separation.

[0044] 2.2 Dust Removal Unit (Cyclone Separator + Scrubber) Even after cooling, the crude coal gas still carries a large amount of dust and fine ash particles, which are then processed sequentially through a cyclone separator and a scrubbing tower. The cyclone separator uses centrifugal force to remove large-diameter dust particles; the scrubbing tower (water washing) washes away residual fine dust and water-soluble impurities (such as NH3) through sufficient contact between water and gas. The purpose of dust removal is to protect the downstream desulfurization catalyst and low-temperature methanol washing solvent from contamination or abrasion by solid particles, thereby extending the life of the unit.

[0045] 2.3 Low-temperature methanol washing unit (acid gas removal) The low-temperature methanol washing unit utilizes low-temperature methanol as a physical absorbent solvent to selectively absorb acidic gases such as H2S, COS, and CO2 from crude coal gas under low-temperature (approximately -40℃ to -60℃) and high-pressure conditions. The key advantages of low-temperature methanol washing are: high solubility, high selectivity, low solvent regeneration energy consumption, and simultaneous deep removal of H2S (reducing the H2S content in the gas to the ppm level). It can also concentrate and capture CO2 when needed. The purified gas, with CO and H2 as the main effective components, at a pressure of approximately 5.5 MPa, can be directly fed into the methanol synthesis process.

[0046] In conventional coal-to-methanol (CTM) systems, a water-gas shift (WGS) reactor is installed before or after purification to react excess CO and H2O in the crude coal gas into H2, achieving the H2 / CO ratio (approximately 2.1) required for methanol synthesis. This invention, based on a conventional coal-to-methanol plant and a high-temperature fuel cell electrolyzer for the co-production of green alcohol and green ammonia, utilizes a SOEC electrolysis hydrogen production module that provides a large amount of green hydrogen (H2). With a sufficient overall H2 supply, the system no longer requires an energy-intensive shift reaction to adjust the hydrogen-to-carbon ratio. Therefore, the water-gas shift module is eliminated, simplifying the process and reducing steam consumption and system heat load.

[0047] <Methanol Synthesis and Gas-Liquid Separation Module> The methanol synthesis and gas-liquid separation module includes a gas compression unit, a methanol synthesis unit, a gas-liquid separator, and a purification unit.

[0048] Raw material change: purified gas (CO+H2) → crude methanol (liquid) + purge gas (containing unreacted gas).

[0049] 3.1 Gas compression device In some embodiments, the gas compression device is preferably a compressor.

[0050] The purified gas (approximately 5.5 MPa) is further pressurized by a compressor to the operating pressure required for the methanol synthesis reaction (typically 5-10 MPa). A recirculation compressor is also installed in the recirculation gas loop to repressurize the separated unreacted gas and send it back to the methanol synthesis unit, maintaining the pressure balance and flow stability of the gas in the recirculation loop.

[0051] 3.2 Methanol Synthesis Unit In some embodiments, the methanol synthesis unit is preferably a methanol synthesis tower.

[0052] The methanol synthesis tower is the core reactor for the methanol synthesis reaction. It is filled with a copper-based catalyst (Cu / ZnO / Al2O3). Under conditions of approximately 200–280°C and 5–10 MPa, the purified gas mixes with green hydrogen (H2) from the SOEC electrolysis hydrogen production module, and the following main reaction occurs: CO + 2H₂ → CH₃OH (CO hydrogenation to synthesize methanol); CO2 + 3H2 → CH3OH + H2O (CO2 hydrogenation to synthesize methanol); The methanol synthesis tower outlet is a gas-vapor mixture, mainly containing CH3OH, a small amount of ethanol (CH3CH2OH), and unreacted N2, CO, H2, H2O, CH4, CO2, etc. Since methanol synthesis is an equilibrium reaction, the single-pass conversion rate is limited (usually only 30%~40%), therefore a circulating process is needed to improve the overall conversion rate.

[0053] 3.3 Gas-Liquid Separator The methanol synthesis tower outlet mixture is condensed and cooled before entering the gas-liquid separator. Because methanol and water condense into liquids at low temperatures, they are separated from the gaseous components such as H2, CO, N2, CH4, and CO2. The liquid product, crude methanol (mainly containing CH3OH, a small amount of ethanol CH3CH2OH, and H2O), is sent to the distillation process for further purification. Most of the gaseous product is returned to the methanol synthesis tower as recycle gas, with a small portion being released as purge gas to prevent the accumulation of inert gases (CH4, N2, etc.) in the system, which could lead to a decrease in partial pressure and conversion rate.

[0054] 3.4 Purification Equipment The purge gas still contains a considerable proportion of effective gases H2 and CO. Direct emission or burning will cause waste. A purge gas purification device (usually hydrogen membrane separation or pressure swing adsorption PSA) is used to separate the purge gas. The hydrogen-rich permeate gas returns to the inlet of the recycle gas and continues to participate in the methanol synthesis reaction to achieve efficient recovery and utilization of hydrogen; the non-permeate gas (mainly containing CH4, CO, a small amount of H2, N2, CO2) has a relatively high calorific value and is introduced as fuel gas into the SOFC anode in the SOFC stack for electrochemical oxidation power generation, achieving cascaded utilization of energy.

[0055] <SOFC Power Generation and CO2 Enrichment Module> The SOFC power generation and CO₂ enrichment module includes an SOFC stack, a gas turbine unit, and a CO₂ / N₂ separation unit.

[0056] Raw material change: Purge gas non-permeate gas (containing CO, CH4, etc.) → electric energy + waste heat + CO₂-enriched / N₂ tail gas.

[0057] The SOFC (solid oxide fuel cell) module is used to replace the waste heat boiler generator set in the traditional system. The non-permeate gas in the methanol synthesis purge gas (i.e., the tail gas rich in CH4, CO, and a small amount of H2) is used for efficient power generation, and at the same time, CO₂ is in-situ enriched during the electrochemical oxidation process to provide a high-purity carbon source for green methanol synthesis.

[0058] 4.1. SOFC Stack (Anode Side) The non-permeate gas enters the SOFC anode (working pressure is about 0.8 MPa). The working temperature of the SOFC is high (600 - 900 °C). The fuel components on the anode side undergo the following reactions under the action of electrochemical oxidation: H2 + O 2- → H2O + 2e - ; CO + O 2- → CO2 + 2e - ; CH4 + 4O 2- → CO2 + 2H2O + 8e - (after internal reforming); Oxygen ions (O<X 2- ) migrate from the cathode side of the SOFC through the solid oxide electrolyte (such as YSZ, yttrium-stabilized zirconia) to the anode, react with the fuel components through electrochemical oxidation, release electrons, and generate direct current. The power generation efficiency of the SOFC can reach 50% - 60% (the combined cycle efficiency exceeds 80%), which is much higher than the efficiency of traditional waste heat boiler steam turbine power generation (about 30% - 40%), and can significantly reduce the energy consumption and carbon emissions per ton of methanol.

[0059] Since almost all combustible components (H2, CO, CH4) are consumed by electrochemical oxidation, the main components of the anode outlet tail gas become CO2 and H2O (water vapor). After removing water vapor, the CO2 concentration increases significantly to over 90%, achieving in-situ enrichment of CO2, eliminating the complex CO2 capture device in the traditional process, and greatly reducing the energy consumption and cost of carbon capture.

[0060] 4.2, SOFC stack (cathode side) After being preheated, air enters the cathode of the SOFC and undergoes an oxygen reduction reaction under high-temperature catalysis: O2 + 4e - → 2O 2- ; The generated oxygen ions are conducted through the electrolyte to the anode of the SOFC to participate in the electrochemical oxidation of the fuel. The high-temperature oxygen-depleted gas (which has consumed part of the O2) at the cathode outlet of the SOFC enters the gas turbine unit to expand and do work, generating additional mechanical work or electricity, and further improving the overall power generation efficiency of the system.

[0061] 4.3, Gas turbine unit The exhaust gas temperature of the SOFC cathode is still relatively high. By introducing the gas turbine to expand and do work, the thermal energy of the high-temperature gas is further converted into mechanical energy. The combined cycle of the turbine and the SOFC can make the total power generation efficiency of the system exceed the traditional single power generation method, fully utilizing the waste heat of the SOFC exhaust gas, which embodies the principle of cascaded utilization of energy.

[0062] The green alcohol and green ammonia co-production system of the present invention adopts the coupling mode of SOFC (solid oxide fuel cell) and gas turbine, recovering the energy of the exhaust gas of the methanol synthesis unit for power generation, replacing the original waste heat boiler generator set (as indicated by the dotted line in Figure 2 ). After the exhaust gas undergoes the anode reaction of the SOFC, the CO2 enrichment degree increases significantly, which can significantly improve the CO2 capture efficiency, provide a high-purity carbon source for the synthesis of green alcohol, and contribute to the carbon closed-loop of the co-production system.

[0063] 4.4, CO2 / N2 separation unit The high-concentration CO2 / H2O mixed gas at the anode outlet of the SOFC enters the CO2 / N2 separation unit after condensation and dehydration. After membrane separation or pressure swing adsorption (PSA) separation, the separated CO2 (high purity) is used as the carbon source for the synthesis of green alcohol and can also be sent to the SOEC for co-electrolysis to produce CO; the separated N2 (industrial-grade purity) is used as the nitrogen source raw material for the synthesis of green ammonia. The entire separation process makes full use of the advantage of the SOFC to concentrate the CO2 originally dispersed in the tail gas, greatly reducing the technical difficulty and energy consumption of CO2 capture.

[0064] <SOEC electrolytic hydrogen production module> The SOEC electrolysis hydrogen production module includes a renewable energy power generation unit, an SOEC electrolyzer, and a waste heat recovery and thermal management unit.

[0065] Raw material change: Renewable electricity + H2O ( / CO2) → Green hydrogen H2 (+CO synthesis gas).

[0066] The SOEC (Solid Oxide Electrolyte) is the core device for green electricity consumption in the green methanol and green ammonia co-production system based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer. It is also the most critical new module that distinguishes it from the traditional CTM system. The SOEC utilizes green electricity provided by renewable energy sources (wind power, photovoltaic, etc.) to electrolyze water (H2O) or co-electrolyze H2O+CO2 under high-temperature conditions to produce green hydrogen (H2) and syngas (H2+CO).

[0067] 5.1 Renewable Energy Power Generation Unit Wind turbines and photovoltaic arrays convert natural wind and solar energy into electricity, which serves as the driving power source for the SOEC electrolysis hydrogen production module. Because renewable energy is intermittent and fluctuating, and power supply varies with weather and time, a flexible dispatch strategy needs to be designed: SOEC operates at maximum power during periods of abundant green electricity (off-peak grid periods) to enhance hydrogen production and energy storage; while SOFC supplements power generation during periods of insufficient green electricity (peak grid periods) to ensure stable system operation.

[0068] 5.2 SOEC Electrolyzer (Steam Electrolysis) SOEC operates at temperatures of 600~850℃. Water vapor is introduced onto the cathode side, and the following reaction is driven by an applied voltage: Cathode: H₂O + 2e - →H2+O 2- ; Anode: 2O 2- →O2+4e - ; Green hydrogen (H2) is produced at the cathode, and O2 is released at the anode. High-temperature operation lowers the thermodynamic energy barrier for water decomposition (reducing the Gibbs free energy), resulting in significantly higher electrolysis efficiency than room-temperature proton exchange membrane (PEM) electrolyzers, with a theoretical efficiency exceeding 90%. A portion of the produced green hydrogen is directly used for methanol synthesis (to supplement the H2 / CO ratio), another portion is sent to the green ammonia synthesis module, and the remainder is used to supplement the water-gas shift converter at the front end of the SOEC system.

[0069] 5.3 SOEC Electrolyzer (CO2 Co-electrolysis) When the CO2 captured by the SOFC module is fed into the SOEC cathode, the SOEC can perform CO2 / H2O co-electrolysis: Cathode: CO2 + 2e - →CO+O 2-(CO2 electrolysis to CO); Cathode: H₂O + 2e - →H2+O 2- (Hydrogen production by steam electrolysis); The CO produced by co-electrolysis can directly supplement the carbon source required for chlorophyll synthesis, solving the problem of high H2 consumption (requiring 3 times the stoichiometric amount of H2) when hydrogenating pure CO2 to synthesize methanol. By adjusting the H2O / CO2 feed ratio, the H2 / CO ratio of the outlet gas can be flexibly controlled, precisely matching the raw material requirements for chlorophyll synthesis.

[0070] 5.4 Waste Heat Recovery and Thermal Management Unit The waste heat generated by SOFC (including the heat from the stack operation and the waste heat from turbine exhaust) is collected by a regenerator and can provide a heat source for SOEC steam preheating, auxiliary heating of the coal gasification furnace, and preheating of the methanol / ammonia synthesis reactor, thereby realizing the cascade utilization of heat within the system, maximizing the comprehensive energy utilization efficiency, and reducing the demand for external heat sources.

[0071] <Chlorol Synthesis Module> The chlorophyll synthesis module includes a chlorophyll synthesis unit and a distillation unit.

[0072] Raw material change: CO2 / CO + green hydrogen (H2) → green methanol (CH3OH).

[0073] The green methanol synthesis module uses CO2 enriched in SOFCs (or CO converted from SOEC co-electrolysis) and green hydrogen prepared from SOECs as raw materials to synthesize green methanol under the action of a catalyst. Compared with the traditional coal-to-methanol route, this process does not rely on fossil energy and is entirely driven by renewable electricity, realizing the resource utilization of CO2 and the closed carbon cycle.

[0074] 6.1 Chlorol Synthesis Reactor In a chlorophyll synthesis reactor, a copper-based catalyst is packed, and under conditions of 200–280°C and 5–8 MPa, the following reactions occur simultaneously: CO2 + 3H2 → CH3OH + H2O (CO2 hydrogenation to synthesize methanol); CO + 2H₂ → CH₃OH (CO hydrogenation to synthesize methanol); By adjusting the H2 / CO ratio of the syngas at the outlet through SOEC co-electrolysis, the reaction ratios of the two pathways can be precisely controlled, thereby reducing CO2 emissions while increasing methanol yield. The gas-vapor mixture at the reactor outlet is then separated into liquid and refined into industrial-grade or fuel-grade green methanol by a distillation column.

[0075] 6.2 Distillation Unit In some implementations, the distillation unit includes a distillation column.

[0076] Crude methanol contains small amounts of ethanol, water, and other high-boiling-point byproducts, which need to be separated and purified by distillation. The distillation column utilizes the differences in boiling points of the components to separate methanol (boiling point 64.7℃) from water (100℃), ethanol (78.4℃), and impurities with higher boiling points, yielding a finished green methanol product with purity meeting specifications. The distillation process consumes a significant amount of heat; however, some of this heat can be supplied by waste heat from a SOFC (Sodium Hydrocarbon Fuel Cell), reducing external energy consumption.

[0077] <Green Ammonia Synthesis Module> The green ammonia synthesis module includes a mixer, a plasma-coupled electrochemical catalytic ammonia synthesis reaction device, and an ammonia separation unit.

[0078] Raw material change: N2 + green hydrogen (H2) → green ammonia (NH3).

[0079] The green ammonia synthesis module uses N2 separated from SOFC anode tail gas and green hydrogen prepared from SOEC as raw materials. It synthesizes green ammonia under mild conditions through plasma-coupled electrochemical catalytic ammonia synthesis technology, which breaks away from the limitations of the traditional Haber process for ammonia synthesis, which requires high temperature (400~500℃) and high pressure (15~30MPa).

[0080] 7.1 Mixer High-purity N2 from the N2 separation unit of the methanol synthesis plant is mixed with green hydrogen H2 supplied by SOEC under the drive of a blower. The mixture is precisely proportioned according to the stoichiometric ratio of ammonia synthesis (N2:H2=1:3) to form a uniform N2 / H2 reaction mixture, which is then sent to the ammonia synthesis reactor.

[0081] 7.2 Plasma-coupled electrochemical catalytic ammonia synthesis reactor The traditional Haber-Bosch process for ammonia synthesis relies on iron-based catalysts and requires the destruction of nitrogen-nitrogen triple bonds (N≡N bond energy is 940 kJ / mol) under extremely high temperature and pressure conditions to activate N2, resulting in extremely high energy consumption.

[0082] The working principle of plasma-coupled electrochemical catalysis technology is as follows: Plasma discharge excites or partially dissociates N2 molecules, significantly reducing the energy barrier required for N≡N bond activation, allowing N2 to be activated at lower temperatures. Electrochemical catalysis further promotes the reaction of activated nitrogen species with H2 on the catalyst surface to generate NH3. The two coupled and synergistically enable efficient ammonia synthesis under temperature and pressure conditions far lower than the Haber process (close to ambient temperature and pressure or low temperature and low pressure), significantly reducing system energy consumption and construction investment.

[0083] The reaction outlet is a mixture of N2, H2 and NH3, while unreacted N2 and H2 enter the subsequent recycling separation process.

[0084] 7.3 Ammonia Separation Unit The mixed gas enters the separation unit (condensation separation or absorption separation). NH3 can be condensed and liquefied at a relatively low temperature (boiling point at atmospheric pressure -33.4℃), achieving phase separation with gaseous N2 and H2 to obtain high-purity liquid ammonia product. Most of the unconverted N2 and H2 (separated gas) is recycled back to the mixer to continue participating in the synthesis reaction, with a small amount used for internal system regulation or emission to ensure that inert gases do not accumulate in the system.

[0085] A method for co-producing green alcohol and green ammonia based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer, using the aforementioned green alcohol and green ammonia co-production system.

[0086] <Example> A green alcohol and green ammonia co-production system based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer is illustrated in the following process flow diagram: Figure 2 As shown: 1) Raw coal is ground into pulverized coal G1 by a coal mill. Pulverized coal G1 is mixed with water to obtain coal-water slurry G2. The coal-water slurry G2 is pumped to the gasifier inlet by a high-pressure coal slurry pump (or pulverized coal G1 is directly added to the gasifier with the help of power equipment). At the same time, oxygen G6 is introduced into the gasifier. The coal-water slurry G2 reacts in the gasifier to obtain high-temperature crude coal gas G7.

[0087] 2) The high-temperature crude coal gas G7 is cooled by a heat exchanger to obtain low-temperature crude coal gas G8; the low-temperature crude coal gas G8 is sprayed and washed to obtain low-temperature coal gas G9; the low-temperature coal gas G9 is divided into low-temperature coal gas G10a and low-temperature coal gas G10b; the low-temperature coal gas G10a is bypassed and regulated to obtain low-temperature coal gas G11a; the low-temperature coal gas G10b is subjected to water-steam conversion to obtain low-temperature coal gas G11b; the low-temperature coal gas G11a and low-temperature coal gas G11b are combined to obtain mixed low-temperature coal gas G12; and then the mixed low-temperature coal gas G12 is washed with low-temperature methanol to obtain purified gas G13.

[0088] 3) The purified gas G13, high-pressure hydrogen-rich gas G24, and recycle gas G25 are mixed to obtain syngas G14. Syngas G14 is compressed and pressurized by a compressor to obtain high-pressure syngas G15. High-pressure syngas G15 is heated by a syngas heater to obtain high-temperature high-pressure syngas G16. High-temperature high-pressure syngas G16 is sent to a methanol synthesis unit to react and obtain high-temperature crude methanol G17. High-temperature crude methanol G17 is condensed and cooled by a cooler to obtain medium-temperature crude methanol G18. Medium-temperature crude methanol G18 is further cooled to obtain low-temperature crude methanol G19. Low-temperature crude methanol G19 is separated to obtain crude methanol G20 (methanol + water), purge gas G21, and recycle gas G25. Purge gas G21 is sent to a hydrogen recovery and purification unit for separation and purification to obtain hydrogen-rich permeate gas G22 and non-permeate gas G26.

[0089] 4) After the non-permeable gas G26 is diverted to the traditional preheating boiler system, fuel cell anode gas G27 is obtained. Fuel cell anode gas G27 is passed through a heat exchanger to obtain medium-temperature fuel cell anode gas G28. Medium-temperature fuel cell anode gas G28 is further heat-exchanged to obtain high-temperature fuel cell anode gas G29. High-temperature fuel cell anode gas G29 enters the SOFC anode in the SOFC stack, and after reaction, anode outlet tail gas G30 is obtained. Anode outlet tail gas G30 is cooled by heat exchange to obtain medium-temperature anode outlet tail gas G31. Medium-temperature anode outlet tail gas G31 is condensed and dehydrated by a cooler to obtain low-temperature anode outlet tail gas G32. Low-temperature anode outlet tail gas G32 is passed into a CO2 / N2 separation unit to separate lean nitrogen anode outlet tail gas G34 and high-purity nitrogen gas G33. Lean nitrogen anode outlet tail gas G34 is decarbonized to obtain recycled gas G35 and carbon dioxide G36. Air is pressurized and preheated by a compressor before entering the SOFC cathode in the SOFC stack. The exhaust gas from the cathode after the reaction enters the gas turbine for expansion and work, further converting the thermal energy of the cathode exhaust gas into mechanical energy.

[0090] 5) Carbon dioxide G36 enters the CO2 electrolysis system and reacts to produce oxygen G37. The H2O electrolysis system electrolyzes water to produce hydrogen G23 and oxygen G3. Oxygen G37 and oxygen G3 are mixed to produce oxygen product G4. Oxygen product G4 is processed by oxygen equipment and regulation to produce green oxygen G5. Green oxygen G5 is combined with oxygen from the traditional air separation system to produce oxygen supply G6 from the gasifier.

[0091] 6) The recycled gas G35, hydrogen-rich permeate gas G22, and hydrogen G23 are fed into a compressor to obtain high-pressure hydrogen-rich gas G24; the purified gas G13, high-pressure hydrogen-rich gas G24, and recycled gas G25 are mixed to obtain syngas G14; syngas G14 is compressed and pressurized by a compressor to obtain high-pressure syngas G15; high-pressure syngas G15 is heated by a syngas heater to obtain high-temperature high-pressure syngas G16; high-temperature high-pressure syngas G16 is sent to a methanol synthesis unit to react and obtain high-temperature crude methanol G17; high-temperature crude methanol G17 is condensed and cooled by a cooler to obtain medium-temperature crude methanol G18; medium-temperature crude methanol G18 is further cooled to obtain low-temperature crude methanol G19; low-temperature crude methanol G19 is separated to obtain crude methanol G20 (methanol + water), purge gas G21, and recycled gas G25; crude methanol G20 is distilled in a distillation column to obtain green methanol.

[0092] 7) High-purity nitrogen gas G33, under the action of a blower, mixes with hydrogen gas G38 supplied by the electrolysis H2O system in a mixer to obtain N2 / H2 reaction mixture gas G39. Then, N2 / H2 reaction mixture gas G39 enters the plasma-coupled electrochemical catalytic ammonia synthesis reactor to react and obtain N2 / H2 / NH3 mixture gas G40. N2 / H2 / NH3 mixture gas G40 enters the separation device (condensation separation) to obtain high-purity ammonia G41 and N2 / H2 mixed separation gas G42. N2 / H2 mixed separation gas G42 enters the mixer to continue to participate in the reaction.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A green alcohol and green ammonia co-production system based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer, characterized in that, include: The module includes: raw material pretreatment and gasification module, coal gas purification module, methanol synthesis and gas-liquid separation module, SOFC power generation and CO2 enrichment module, SOEC electrolysis module, chlorohydrin synthesis module, and chloroammonia synthesis module. The raw material pretreatment and vaporization module is used to generate crude coal gas; The gas purification module is used to purify crude coal gas and generate purified gas. The methanol synthesis and gas-liquid separation module includes a methanol synthesis unit, a gas-liquid separator, and a purification unit. The purified gas is fed to the methanol synthesis unit to undergo a synthesis reaction to obtain a gas-vapor mixture; the gas-vapor mixture is condensed and cooled before entering a gas-liquid separator to separate liquid and gaseous products; The gaseous products include recycle gas and purge gas; the purge gas is sent to a purification unit for purification to obtain hydrogen-rich permeate gas and non-permeate gas; the recycle gas and hydrogen-rich permeate gas are returned to the methanol synthesis unit to continue participating in the synthesis reaction; The SOFC power generation and CO2 enrichment module includes an SOFC stack and a CO2 / N2 separation unit. The non-permeable gas is fed to the SOFC anode in the SOFC stack to participate in the electrochemical oxidation reaction of the fuel to obtain a CO2 / H2O mixed gas; the CO2 / H2O mixed gas is condensed and dehydrated and then enters the CO2 / N2 separation unit to separate CO2 and N2; The SOEC electrolysis module includes an SOEC electrolysis cell; The CO2 separated by the CO2 / N2 separation unit is sent to the SOEC electrolytic cell to undergo CO2 / H2O co-electrolysis to obtain CO and H2; The CO2 separated by the CO2 / N2 separation unit and / or the CO and H2 obtained by co-electrolysis of CO2 / H2O are transported to the chloroethanol synthesis module to synthesize methanol. The N2 separated by the CO2 / N2 separation unit and the H2 obtained by co-electrolysis of CO2 / H2O are transported to the green ammonia synthesis module to synthesize ammonia.

2. The chlorohydrin and chloroammonia co-production system as described in claim 1, characterized in that, The methanol synthesis and gas-liquid separation module also includes a gas compression device; And / or, the SOFC power generation and CO2 enrichment module further includes a gas turbine unit, in which the SOFC cathode exhaust in the SOFC stack enters the gas turbine unit for expansion and work, converting thermal energy into mechanical energy.

3. The chlorohydrin and chloroammonia co-production system as described in claim 1, characterized in that, The SOEC electrolysis module also includes a renewable energy power generation unit, which converts renewable energy into electrical energy and uses it as the power source for the SOEC electrolyzer.

4. The chlorohydrin and chloroammonia co-production system as described in claim 1, characterized in that, The chlorophyll synthesis module includes a chlorophyll synthesis reactor and a distillation unit.

5. The chlorohydrin and chloroammonia co-production system as described in claim 4, characterized in that, The CO2 and / or CO and H2 are fed to the chlorophyll synthesis reactor to undergo a synthesis reaction to obtain crude methanol, which is then separated and purified by a distillation unit to obtain methanol.

6. The chlorophyll and chloroammonia co-production system as described in claim 1, characterized in that, The green ammonia synthesis module includes a mixer, a plasma-coupled electrochemical catalytic ammonia synthesis reaction device, and an ammonia separation unit.

7. The chlorohydrin and chloroammonia co-production system as described in claim 6, characterized in that, The N2 and H2 are mixed in a mixer to obtain an N2 / H2 reaction mixture; the N2 / H2 reaction mixture enters a plasma-coupled electrochemical catalytic ammonia synthesis reactor to react and obtain a mixture of N2, H2 and NH3; the mixture enters an ammonia separation unit for condensation and liquefaction to obtain liquid NH3.

8. The chlorohydrin and chloroammonia co-production system as described in claim 1, characterized in that, The raw material pretreatment and gasification module includes a grinding mill, a high-pressure coal slurry pump, and a gasifier; Raw coal is ground into pulverized coal by a coal mill. The pulverized coal is mixed with water to obtain coal-water slurry. The coal-water slurry is pressurized to the operating pressure required for gasification by a high-pressure coal slurry pump and then pumped into a gasifier to undergo a gasification reaction to obtain crude coal gas.

9. The chlorohydrin and chloroammonia co-production system as described in claim 1, characterized in that, The gas purification module includes a heat exchanger, a dust removal unit, and a low-temperature methanol washing unit; The crude coal gas is gradually cooled by a heat exchanger and then enters a dust removal unit to remove dust and water-soluble impurities. It then enters a low-temperature methanol washing unit to remove acidic gases and obtain purified gas.

10. A method for co-producing green alcohol and green ammonia based on a traditional coal-to-methanol plant and a high-temperature fuel cell electrolyzer, characterized in that, The co-production system of chlorohydrin and chloroammonia as described in any one of claims 1 to 9 is adopted.

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