Process method for preparing green methanol by combining biomass with combined heat and power generation technology
By combining biomass with cogeneration technology, the problems of low efficiency and high energy consumption of biomass methanol production are solved, efficient conversion and green production are achieved, high-purity green methanol is obtained, and high-purity green methanol has good industrial application prospects.
Patent Information
- Application Number
- CN202510830506.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-20
- Publication Date
- 2025-07-25
AI Technical Summary
The existing biomass methanol production technology has low efficiency, high energy consumption, unstable product quality, and is difficult to promote and apply on a large scale.
In combination with cogeneration technology, green methanol is produced through biomass pretreatment, gasification, waste heat utilization, desulfurization and dust removal, compression synthesis, methanol distillation and electrolyzing hydrogen production, and high-temperature synthesis gas power generation and waste heat boiler generate steam-driven generator sets to improve gasification efficiency and reduce energy consumption.
It achieves efficient conversion from biomass to methanol, improves raw material utilization, reduces energy consumption, ensures product quality, reduces pollutant emissions, and meets green and environmental protection requirements.
Smart Images
Figure CN120365957A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a process for producing green methanol by combining biomass with cogeneration technology. Background Art
[0002] Traditional methanol production mostly relies on fossil energy and faces problems of limited resources and environmental issues. With the increasing demand for clean energy, using biomass to produce methanol has become a research hotspot. However, existing biomass-to-methanol technologies have problems such as low efficiency, high energy consumption, and unstable product quality, making it difficult to be widely promoted and applied on a large scale.
[0003] The purpose of the present invention is to provide a process and system for producing green methanol by combining biomass with cogeneration technology, to improve the efficiency and quality of biomass conversion into methanol. The green electricity generated by the combustion of high-temperature biomass gas is mainly for in-plant use, and the excess green electricity is sold to the grid. The aim is to improve the comprehensive energy utilization efficiency so as to reduce energy consumption and achieve green and sustainable production.
[0004] Different from the conventional process for producing methanol from biomass, this invention patent adds a cogeneration unit. Part of the high-temperature biomass syngas is sent to a gas boiler for combustion to produce superheated steam, which is sent to a supplementary steam condensing steam turbine generator set to produce green electricity. And the low-pressure steam produced by the waste heat boiler is sent to the gasification device to react with carbon, further improving the gasification efficiency of the gasification device and increasing the gasification products. Summary of the Invention
[0005] The object of the present invention is to specifically design for the pain points of existing biomass-to-methanol technologies, such as low efficiency, high energy consumption, and unstable product quality, and design a process and system for producing green bio-methanol by combining biomass gasification with cogeneration technology, to improve the efficiency and quality of biomass conversion into methanol, improve the comprehensive energy utilization efficiency so as to reduce energy consumption, and achieve green and sustainable production.
[0006] The solution adopted by the present invention to solve the technical problem is a process for producing green methanol by combining biomass with cogeneration technology, including biomass pretreatment, gasification, waste heat utilization, desulfurization and dust removal, compression and synthesis, methanol rectification, and by-products. After producing green electricity through cogeneration technology, electrolyzing water to produce hydrogen as a raw material for methanol synthesis, and using the oxygen produced by electrolyzing water as an auxiliary combustion agent for the gas boiler or the gasification device, etc.
[0007] The biomass raw material pretreatment device screens, dries, and pulverizes the biomass raw material for pretreatment to make it meet the requirements of subsequent gasification reactions; Furthermore, the biomass gasification device uses the pretreated biomass in a gasification furnace to undergo a gasification reaction under specific temperature, pressure, and gasifying agent to generate syngas; Furthermore, a part of the high-temperature syngas enters the waste heat boiler to generate medium-pressure steam and low-pressure steam. The medium-pressure steam is used for power generation by the steam extraction steam turbine generator set, and the low-pressure steam is used for other heating processes within the system. Furthermore, a part of the high-temperature syngas generated during the gasification process enters the gas boiler for combustion to generate ultra-high-pressure steam for driving the steam extraction condensing steam turbine generator set for power generation. The system is equipped with an electrolytic water hydrogen production device, and the generated electric energy is supplied for the self-use of in-plant equipment. Part of the electric energy is used for electrolytic water hydrogen production to supplement the hydrogen source of the system, and the excess hydrogen is stored in the hydrogen storage device. Furthermore, a part of the syngas enters the desulfurization and dust removal device after waste heat utilization to remove sulfur impurities and dust. Furthermore, after the purified syngas is mixed with the hydrogen provided by the hydrogen storage device, it enters the methanol synthesis reactor after compression and undergoes a synthesis reaction under the action of a catalyst to produce methanol, and the hydrogen can be recycled. Furthermore, the synthesized crude methanol enters the distillation column for distillation to obtain a high-purity green methanol product.
[0008] Compared with the prior art, the present invention has the following obvious effects: First, through reasonable process design, the efficient conversion of biomass to methanol is realized, and the raw material utilization rate is improved. Second, the combination of waste heat recovery utilization and surplus energy application with the cogeneration technology reduces the system energy consumption and improves the comprehensive energy utilization efficiency. Third, the strict purification process ensures the product quality, obtains high-purity green methanol, and reduces pollutant emissions, meeting the requirements of green environmental protection. Fourth, the system has a high degree of integration, and each unit works in coordination, enabling stable and continuous production, and having good industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The following further describes the present invention in conjunction with the drawings.
[0010] Figure 1 It is a flow schematic diagram of the process method.
[0011] In the figure: 1 - Biomass raw material pretreatment device; 2 - Biomass gasification device; 3 - Waste heat boiler; 4 - High-temperature gas boiler; 5 - Steam extraction condensing steam turbine generator set; 6 - Electrolytic water hydrogen production device; 7 - Desulfurization and dust removal device; 8 - Compression device; 9 - Methanol synthesis device; 10 - Methanol distillation device; 11 - Hydrogen storage device; 12 - Oxygen storage device. DETAILED DESCRIPTION OF THE INVENTION
[0012] The following further describes the present invention in conjunction with the drawings and specific embodiments.
[0013] As Figure 1As shown in the figure, a process for producing green methanol by biomass combined heat and power generation technology includes a biomass raw material pretreatment device, a biomass gasification device, a waste heat boiler, a high-temperature gas boiler, a steam extraction condensing steam turbine generator set, an electrolytic water hydrogen production device, a desulfurization and dust removal device, a compression device, a methanol synthesis device, a methanol rectification device, a hydrogen storage device, and an oxygen storage device. The biomass pretreatment device (1) includes screening equipment, drying equipment, and crushing equipment for preprocessing biomass raw materials. The preprocessed biomass is sent to the biomass gasification device (2) which includes a gasifier and related auxiliary equipment to achieve biomass gasification reaction and produce high-temperature biomass syngas. Part of the high-temperature syngas enters the waste heat boiler (3) to recover the waste heat of the syngas and produce medium-pressure and low-pressure steam. The low-pressure steam is sent to the biomass gasification device (2) to improve the gasification efficiency. The cooled biomass syngas is sent to the desulfurization and dust removal device (7) for purification treatment. Part of the high-temperature syngas is sent to the gas boiler (4) to produce ultra-high-pressure steam, which is sent to the steam extraction condensing steam turbine generator set (5) to produce green electric energy. The medium-pressure steam produced by the waste heat boiler (3) is sent to the steam extraction condensing steam turbine generator set (5) in the form of steam extraction to increase the output of green electric energy. The electrolytic water hydrogen production device (6) is set up using the produced green electric energy. The electrolytic water hydrogen production device (6) outputs oxygen and sends it to the biomass gasification device (2) to improve the gasification efficiency. The hydrogen produced by the electrolytic water hydrogen production device (6) and the biomass syngas purified by the desulfurization and dust removal device (7) are sent to the methanol synthesis device (9) through the compression device (8) to synthesize crude methanol, and the crude methanol is sent to the methanol rectification device (10) to obtain high-purity green methanol products. The excess hydrogen produced by the electrolytic water hydrogen production device (6) is sent to the hydrogen storage device (11), and the excess oxygen is sent to the oxygen storage device (12) to achieve the system storage and supply function.
[0014] For any of the technical solutions disclosed in this patent as described above, unless otherwise stated, if it discloses a numerical range, the disclosed numerical range is a preferred numerical range. Any person skilled in the art should understand that the preferred numerical range is only the numerical values with obvious technical effects or representativeness among many implementable numerical values. Since there are too many numerical values to list exhaustively, only some numerical values are disclosed in this invention to illustrate the technical solutions of this invention. Moreover, the numerical values listed above should not constitute a limitation on the protection scope of this invention.
[0015] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the patent and not to limit them. Although this patent has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that it is still possible to modify the specific implementation manners of this patent or make equivalent replacements for some technical features without departing from the spirit of the technical solutions of this patent, and they should all be covered within the scope of the technical solutions claimed by this patent.
Claims
1. A process for producing green methanol by biomass combined heat and power generation technology, characterized in that It includes the following steps: 1.1 Screen, dry, and crush the biomass raw materials for pretreatment to meet the requirements of subsequent gasification reactions; 1.2 The pretreated biomass undergoes a gasification reaction in a gasifier under specific temperature, pressure, and gasifying agent to generate syngas; 1.3 Part of the high-temperature syngas enters a waste heat boiler to produce medium-pressure steam and low-pressure steam. The medium-pressure steam is used for power generation in a supplementary steam turbine generator set, and the low-pressure steam is used for other heating processes within the system; 1.4 Part of the high-temperature syngas enters a gas-fired boiler for combustion to produce ultra-high-pressure steam for driving a supplementary steam condensing steam turbine generator set for power generation; The system is equipped with an electrolytic water hydrogen production device, and the generated electric energy is supplied for the self-use of in-plant equipment. Part of the electric energy is used for electrolytic water hydrogen production to supplement the hydrogen source of the system. The excess hydrogen is stored in a hydrogen storage device, and the excess electric energy is sold to the grid; 1.5 After the syngas is utilized for waste heat, it enters a desulfurization and dust removal device to remove sulfur impurities and dust; 1.6 After the purified syngas is mixed with the hydrogen provided by the hydrogen storage device, it is compressed and enters a methanol synthesis reactor, where a synthesis reaction occurs under the action of a catalyst to produce methanol, and the hydrogen can be recycled; 1.7 The synthesized crude methanol enters a distillation column for distillation to obtain a high-purity green methanol product.
2. The process method for producing green methanol by combining biomass with cogeneration technology according to claim 1, characterized in that: The biomass raw materials include straw, wood waste, etc.
3. A process for producing green methanol by combining biomass with a cogeneration technology according to claim 1, characterized in that: The gasifying agent is a mixture of oxygen and water vapor, the gasification temperature is 800 - 1000 °C, and the steam pressure is 0.1 - 0.5 MPa.
4. A process for producing green methanol by combining biomass with a cogeneration technology according to claim 1, characterized in that: The medium-pressure steam pressure is 2 - 4 MPa, and the temperature is 300 - 400 °C; The low-pressure steam pressure is 0.1 - 0.5 MPa, and the temperature is 130 - 180 °C.
5. A process for producing green methanol by combining biomass with a cogeneration technology according to claim 1, characterized in that: The ultra-high-pressure steam pressure is: 10 - 14 MPa, and the temperature is 535 - 570 °C.
6. A process for producing green methanol by combining biomass with a cogeneration technology according to claim 1, characterized in that: The sulfur content in the desulfurized and dust-removed syngas is less than 35 mg / m³, and the dust content is less than 5 mg / m³.
7. A process for producing green methanol by combining biomass with a cogeneration technology, as claimed in claim 1, characterized in that: The purified syngas is mixed with hydrogen at a molar ratio of 1:2 or 1:3, compressed to a pressure of 5 - 10 MPa and enters a methanol synthesis reactor, and the reaction temperature is 200 - 300 °C.
8. A process for producing green methanol by combining biomass with a cogeneration technology, as claimed in claim 1, wherein: The steam required for distillation is sourced from the extraction steam system of a supplementary steam condensing steam turbine generator set, and the purity of the green methanol product obtained after distillation reaches over 99%.
9. A system for producing green methanol from biomass implementing the process method described in any one of claims 1 - 8, characterized in that it includes: 9.1 A pretreatment unit, including screening equipment, drying equipment, and crushing equipment, for pretreating biomass raw materials; 9.2 A gasification unit, including a gasifier and related auxiliary equipment, to achieve biomass gasification reactions; 9.3 A waste heat utilization unit, namely a waste heat boiler, to recover the waste heat of syngas to produce steam; 9.4 A purification unit, composed of desulfurization and dust removal equipment, to purify syngas; 9.5 A synthesis and distillation unit, including compression equipment, a methanol synthesis reactor, and a distillation column, to complete methanol synthesis and distillation; 9.6 An energy and by-product treatment unit, including a gas-fired boiler, a supplementary steam condensing steam turbine generator set, an electrolytic water hydrogen production device, an oxygen storage device, a hydrogen storage device, and a hydrogen recovery device, to process by-products and supplement energy.