Coal and biomass co-gasification method

Abstract

The invention provides a coal and biomass co-gasification method, and belongs to the technical field of energy engineering. According to the method, the coal gasification efficiency can be remarkably improved and the emission of harmful gas can be reduced by optimizing the types, proportions and reaction conditions of the gasification raw materials. The gasification reaction of the coal is promoted by utilizing the high reaction activity of the specific biomass, so that the energy consumption of the whole gasification process is reduced. Through the co-gasification process, efficient utilization of coal and biomass resources is achieved, and the energy conversion rate is increased. The co-gasification method can adapt to different types of coal and biomass raw materials, and has good universality and flexibility. The co-gasification technology has remarkable economic benefits in industrial application, the production cost can be reduced, and the economic benefits can be improved.

Description

Technical Field

[0001] The present invention relates to the field of energy engineering technology, and in particular to a method for co-gasification of coal and biomass. Background Art

[0002] Coal gasification technology is a chemical technology that converts coal into combustible gas. The gasification process is a thermochemical processing process of coal. It uses coal or coal coke as raw materials, oxygen (air, oxygen-enriched or industrial pure oxygen) and water vapor as gasifying agents, and converts the combustible part of coal or coal coke into combustible gas through chemical reactions under high temperature and pressure. The combustible gas obtained during gasification becomes coal gas. The coal gas used as a chemical raw material is generally called synthesis gas (in addition to coal as raw material, synthesis gas can also use natural gas, heavy petroleum components, etc. as raw materials). The equipment for gasification is called a gasifier or gasifier.

[0003] Coal gasification involves a series of physical and chemical changes. Generally, it includes four stages: drying, combustion, pyrolysis and gasification. Drying is a physical change. As the temperature rises, the water in the coal evaporates due to heat. Other changes are chemical changes, and combustion can also be considered as part of gasification. After the coal is dried in the gasifier, as the temperature further rises, the coal molecules undergo thermal decomposition reactions to generate a large amount of volatile substances (including dry distillation gas, tar and pyrolysis water, etc.), and the coal is bonded into semi-coke. The semi-coke formed after coal pyrolysis reacts chemically with the gasifier introduced into the gasifier at a higher temperature to generate gaseous products with carbon monoxide, hydrogen, methane, carbon dioxide, nitrogen, hydrogen sulfide, water, etc. as the main components, namely raw coal gas. The gasification reaction includes many chemical reactions, mainly the reactions between carbon, water, oxygen, hydrogen, carbon monoxide and carbon dioxide. Among them, the reaction between carbon and oxygen is also called combustion reaction, which provides heat for the gasification process.

[0004] In the existing technical field, although coal gasification technology has been applied to a certain extent, it still has some significant shortcomings. Specifically, the efficiency of these technologies is generally low, which means that a lot of energy is wasted in the process of converting coal into usable gas. In addition, these technologies are often accompanied by serious environmental pollution problems during operation, such as the emission of large amounts of carbon dioxide and other harmful gases, which not only has a negative impact on the environment, but also increases the difficulty and cost of subsequent treatment.

[0005] Therefore, in order to improve the practicality and sustainability of coal gasification technology, it is urgently needed to improve and optimize it. The direction of improvement can include improving the thermal efficiency of the gasification process and reducing energy waste; at the same time, developing more environmentally friendly gasification processes and reducing the emission of harmful gases, thereby reducing the burden on the environment. Through these improvement measures, coal gasification technology is expected to play a greater role in future energy utilization and better meet the requirements of environmental protection.

[0006] Chinese patent CN102786989B discloses a device for the co-gasification method of biomass and coal in a fluidized bed, including a fluidized bed combustion inner cylinder and a fluidized bed gasification outer cylinder of an inner and outer cylinder structure, as well as a matching gas-solid separation system and a return system, wherein two gasification agent inlets are respectively located at the upper and lower parts of the fluidized bed gasification outer cylinder to enhance the fluidization effect, so that the gasification reaction can be fully carried out, and at the same time, by changing the ratio of CO2 to water vapor in the gasification agent, a synthesis gas with different volume fraction ratios of H2 and CO is obtained; two feed ports are respectively provided to enter the gasification outer cylinder and the combustion inner cylinder, and the reaction process can be controlled by adjusting the feed amount; an inertial separator is used to control the material circulation amount by adjusting the compressed air feed amount and the lower L valve push gas feed amount, and it is not affected by other factors. The gasification equipment has a simple structure, high thermal efficiency, simple and convenient control, and extremely strong flexibility.

[0007] Chinese patent CN107189821A discloses a dry coal powder coupled biomass co-gasification descending quenching gasifier, comprising a gasifier shell, a water-cooled wall with a circulating water inlet and a circulating water outlet is arranged in the gasifier shell, a plurality of gas pulverized coal burners are arranged horizontally on the upper part of the gasifier shell, a burner integrated with biomass and gasifier ignition and start-up is arranged vertically on the top of the gasifier shell, and the burner is fixedly sealed by a top cover and the gasifier shell; the bottom of the water-cooled wall is connected to the top of the quenching tank through a partition plate, the bottom of the partition plate is connected to the quenching ring, the quenching ring is connected to the top of the downcomer, a bubble breaker is fixed between the outer wall of the downcomer and the inner wall of the gasifier shell, the quenching water inlet of the quenching ring is connected to the quenching water inlet arranged on the outer wall of the quenching tank, and the outer wall of the quenching tank is provided with a synthesis gas outlet and a slag water outlet. The present invention realizes the co-gasification of pulverized coal and biomass, is convenient for gasifier temperature control, and adopts a descending quenching form, so that the subsequent purification and dust removal system has a small burden, low energy consumption and high efficiency.

[0008] However, none of the above existing technologies can achieve the improvement of coal gasification effect while utilizing biological resources. Summary of the invention

[0009] The object of the present invention is to provide a method for co-gasification of coal and biomass, which can achieve efficient utilization of coal and biomass resources, improve energy conversion efficiency and reduce pollution.

[0010] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0011] The present invention provides a method for co-gasification of coal and biomass, comprising the following steps:

[0012] mixing coal, agricultural and forestry residues, fungus cultivation substrate and shell waste to obtain a mixture;

[0013] The mixture is sequentially dried and crushed to obtain a crushed product;

[0014] The pulverized material is co-gasified.

[0015] Preferably, the coal is selected from one or more of coking coal, bituminous coal, lean coal, gas coal, non-caking coal, lean coal, raw coal, washed coal, peat, fat coal, lignite, long flame coal, weakly caking coal, medium caking coal, thermal coal, coal fines, candle coal or sub-bituminous coal.

[0016] Preferably, the agricultural and forestry residues are selected from one or more of forestry residues, waste wood, wood chips, crop straw or waste crop residues.

[0017] Preferably, the crop straw or waste crop residue comes from wheat, rice, corn, potato, rapeseed, cotton or sugarcane.

[0018] Preferably, the mixture comprises the following components in parts by weight:

[0019] 80-120 parts of coal, 40-80 parts of agricultural and forestry residues, 10-30 parts of fungus cultivation substrate, and 10-30 parts of shell waste.

[0020] Preferably, the drying temperature is 60-90°C;

[0021] The drying time is 5 to 7 hours.

[0022] Preferably, the crushed particles have a particle size of less than 300 μm.

[0023] Preferably, a process gas is introduced during the co-gasification process;

[0024] The process gas is nitrogen;

[0025] The flow rate of the process gas is 2 to 3 L / s.

[0026] Preferably, the co-gasification temperature is 600-900°C;

[0027] The co-gasification time is 20 to 40 minutes.

[0028] The present invention also provides the application of the above-mentioned coal and biomass co-gasification method in increasing the H2 and CH4 production in the product gas, reducing CO2 generation, lowering the temperature required for co-gasification or increasing the calorific value of combustible gas.

[0029] Technical effects and advantages of the present invention:

[0030] The present invention can significantly improve the efficiency of coal gasification and reduce harmful gas emissions by optimizing the types, ratios and reaction conditions of gasification raw materials. The high reactivity of specific biomass is utilized to promote the gasification reaction of coal, thereby reducing the energy consumption of the overall gasification process. Through the co-gasification process, the present invention achieves efficient utilization of coal and biomass resources and improves energy conversion efficiency. The co-gasification method of the present invention can adapt to different types of coal and biomass raw materials and has good versatility and flexibility. The co-gasification technology of the present invention has significant economic benefits in industrial applications, can reduce production costs and improve economic benefits.

[0031] It can be seen from the examples that the coal and biomass co-gasification scheme provided by the present invention can effectively increase the yield of H2 and CH4 in the product gas, while reducing the generation of CO2, compared with the control group; the generated H2 and CH4 can be separated and used as high-efficiency green fuels, which helps to promote the optimization of the energy structure, reduce dependence on fossil fuels, and promote the sustainable development of energy; and the components of the present invention cooperate with each other to achieve further catalysis in the coal gasification process, thereby reducing the temperature required for co-gasification, achieving energy conservation and carbon reduction, and having important significance for environmental protection. DETAILED DESCRIPTION

[0032] The present invention provides a method for co-gasification of coal and biomass, comprising the following steps:

[0033] mixing coal, agricultural and forestry residues, fungus cultivation substrate and shell waste to obtain a mixture;

[0034] The mixture is sequentially dried and crushed to obtain a crushed product;

[0035] The pulverized material is co-gasified.

[0036] In the present invention, preferably, the coal is selected from one or more of coking coal, bituminous coal, lean coal, gas coal, non-sticky coal, lean coal, raw coal, washed coal, peat, fat coal, lignite, long flame coal, weakly sticky coal, medium sticky coal, thermal coal, coal ash, candle coal or sub-bituminous coal; the coal is preferably used in the form of coal powder; the particle size of the coal powder is less than 0.5 mm.

[0037] In the present invention, preferably, the agricultural and forestry residues are selected from one or more of forestry residues, waste wood, wood chips, crop straws or waste crop residues; preferably, the crop straws or waste crop residues come from wheat, rice, corn, potatoes, rapeseed, cotton or sugarcane; in a specific embodiment of the present invention, the agricultural and forestry residues are preferably wood chips and sugarcane bagasse.

[0038] In the present invention, the significance of utilizing agricultural and forestry residues includes the following aspects:

[0039] 1. Agricultural and forestry residues are usually regarded as useless by-products and may even pollute the environment. However, through the technical means of the present invention, these agricultural and forestry residues can be effectively utilized and converted into valuable resources.

[0040] 2. Using agricultural and forestry residues can reduce environmental pollution. Traditional treatment methods such as incineration or disposal not only waste resources, but also produce a large amount of carbon dioxide and other harmful gases, leading to a decline in air quality and an intensification of the greenhouse effect. Through the technology of the present invention, these residues can be converted into bioenergy or other environmentally friendly materials, thereby reducing dependence on fossil fuels and reducing carbon emissions.

[0041] 3. The use of agricultural and forestry residues can also promote the sustainable development of agriculture. By converting these wastes into valuable resources, farmers can obtain additional economic benefits and increase their enthusiasm for agricultural production. At the same time, this resource utilization method can also reduce the use of fertilizers and pesticides, improve soil quality, and increase the yield and quality of crops.

[0042] 4. The use of agricultural and forestry residues can also promote the development of related industries. For example, by converting agricultural and forestry residues into bioenergy, biomass materials, etc., it can drive the development of new energy industries and environmental protection industries, create more employment opportunities, and promote the diversified development of the economy.

[0043] Therefore, the significance of utilizing agricultural and forestry residues in the present invention includes promoting the recycling of resources, reducing environmental pollution, promoting the sustainable development of agriculture, and driving the development of related industries, which has important economic, social and environmental benefits.

[0044] In the present invention, preferably, the mixture includes the following components in parts by weight:

[0045] 80-120 parts of coal, 40-80 parts of agricultural and forestry residues, 10-30 parts of fungus cultivation substrate, and 10-30 parts of shell waste.

[0046] The selection of the types and proportions of co-gasification materials involved in the present invention can give full play to the optimal effect of promoting the coal gasification reaction. Through careful design and optimization, these types and proportions of materials can significantly improve the reaction efficiency during the coal gasification process, thereby achieving the purpose of energy conservation and emission reduction. Specifically, by reasonably matching different types of materials, the energy consumption in the coal gasification process can be effectively reduced, the emission of harmful gases can be reduced, and the quality and output of coal gas can be improved. The innovative co-gasification technology provided by the present invention can not only improve the efficiency of energy utilization, but also play an important role in environmental protection, achieving a dual improvement in economic and environmental benefits.

[0047] In the present invention, preferably, the drying temperature is 60-90°C; the drying time is 5-7h. Preferably, the crushed particle size is below 300μm. Preferably, process gas is introduced during the co-gasification process; the process gas is nitrogen; the flow rate of the process gas is 2-3L / s. Preferably, the co-gasification temperature is 600-900°C; the co-gasification time is 20-40min.

[0048] The co-gasification process parameters involved in the present invention have been carefully designed and optimized to ensure that the gas products produced have the highest quality. These parameters include temperature, pressure, raw material ratio and other factors. Each step is strictly calculated and experimentally verified to ensure that the quality of the final product is optimal. If any changes are made to these parameters, the same high quality effect cannot be achieved. Therefore, it is crucial to follow the process parameters provided by the present invention. Any deviation may lead to a decline in product quality and fail to meet the high standards required in industrial applications.

[0049] The present invention also provides the application of the above-mentioned coal and biomass co-gasification method in increasing the H2 and CH4 production in the product gas, reducing CO2 generation, lowering the temperature required for co-gasification or increasing the calorific value of combustible gas; the application of the present invention also includes using the gas generated by co-gasification as an energy source, such as for power generation or as an industrial fuel, thereby improving energy utilization efficiency and economic benefits.

[0050] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0051] Example 1

[0052] 100 parts of coal powder, 30 parts of poplar sawdust, 30 parts of bagasse, 20 parts of discarded oyster mushroom cultivation substrate and 20 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0053] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0054] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.85g, 14.36g, and 0.38g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5492.26J / L.

[0055] Example 2

[0056] 100 parts of coal powder, 25 parts of poplar sawdust, 30 parts of bagasse, 25 parts of discarded oyster mushroom cultivation substrate and 20 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0057] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0058] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.86g, 14.13g, and 0.47g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5206.19J / L.

[0059] Example 3

[0060] 100 parts of coal powder, 35 parts of poplar sawdust, 30 parts of bagasse, 15 parts of discarded oyster mushroom cultivation substrate and 20 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0061] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0062] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.85g, 14.76g, and 0.41g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5272.42J / L.

[0063] Example 4

[0064] 100 parts of coal powder, 30 parts of poplar sawdust, 25 parts of bagasse, 20 parts of discarded oyster mushroom cultivation substrate and 25 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0065] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0066] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.85g, 14.11g, and 0.44g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5163.52J / L.

[0067] Example 5

[0068] 100 parts of coal powder, 30 parts of poplar sawdust, 35 parts of bagasse, 20 parts of discarded oyster mushroom cultivation substrate and 15 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0069] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0070] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.84g, 14.47g, and 0.38g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5354.92J / L.

[0071] Example 6

[0072] 100 parts of coal powder, 35 parts of poplar sawdust, 25 parts of bagasse, 15 parts of discarded oyster mushroom cultivation substrate and 25 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0073] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0074] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.88g, 15.05g, and 0.49g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5445.44J / L.

[0075] Example 7

[0076] 100 parts of coal powder, 25 parts of poplar sawdust, 25 parts of bagasse, 25 parts of discarded oyster mushroom cultivation substrate and 25 parts of shell waste were dried at 70°C for 7 hours and crushed to a particle size of less than 200 μm;

[0077] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0078] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.90g, 14.40g, and 0.52g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5252.50J / L.

[0079] Example 8

[0080] 100 parts of coal powder, 25 parts of poplar sawdust, 33 parts of bagasse, 18 parts of discarded oyster mushroom cultivation substrate and 25 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0081] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2L / s, and gasifies at 700℃ for 40min.

[0082] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.82g, 14.31g, and 0.51g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5279.89J / L.

[0083] Example 9

[0084] 80 parts of coal powder, 25 parts of poplar sawdust, 25 parts of bagasse, 15 parts of discarded oyster mushroom cultivation substrate and 15 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 150 μm;

[0085] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 700℃ for 30min.

[0086] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.90g, 15.05g, and 0.46g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5256.85J / L.

[0087] Example 10

[0088] 120 parts of coal powder, 35 parts of poplar sawdust, 35 parts of bagasse, 25 parts of discarded oyster mushroom cultivation substrate and 25 parts of shell waste were dried at 80°C for 7 hours and crushed to a particle size of less than 200 μm;

[0089] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 850℃ for 30min.

[0090] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.87g, 14.01g, and 0.45g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5226.91J / L.

[0091] Embodiment 11

[0092] 110 parts of coal powder, 32 parts of poplar sawdust, 32 parts of bagasse, 22 parts of discarded oyster mushroom cultivation substrate and 15 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0093] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 850℃ for 30min.

[0094] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.84g, 14.13g, and 0.43g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5201.07J / L.

[0095] Example 12

[0096] 100 parts of coal powder, 27 parts of poplar sawdust, 25 parts of bagasse, 25 parts of discarded oyster mushroom cultivation substrate and 23 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0097] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 850℃ for 40min.

[0098] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.85g, 14.55g, and 0.49g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5400.40J / L.

[0099] Embodiment 13

[0100] 110 parts of coal powder, 34 parts of poplar sawdust, 28 parts of bagasse, 18 parts of discarded oyster mushroom cultivation substrate and 24 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0101] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 850℃ for 30min.

[0102] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.83g, 14.85g, and 0.51g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5490.01J / L.

[0103] Embodiment 14

[0104] 100 parts of coal powder, 30 parts of poplar sawdust, 30 parts of bagasse, 20 parts of discarded oyster mushroom cultivation substrate and 20 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 100 μm;

[0105] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 850℃ for 30min.

[0106] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.88g, 14.82g, and 0.50g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5336.27J / L.

[0107] Embodiment 15

[0108] 100 parts of coal powder, 30 parts of poplar sawdust, 30 parts of bagasse, 22 parts of discarded oyster mushroom cultivation substrate and 18 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0109] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 3L / s, and gasifies at 900℃ for 30min.

[0110] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.82g, 15.19g, and 0.46g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 5469.75J / L.

[0111] Comparative Example 1

[0112] 100 parts of coal powder and 100 parts of poplar sawdust were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0113] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 800℃ for 30min.

[0114] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.31g, 7.64g, and 2.55g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded as 4017.04J / L.

[0115] Comparative Example 2

[0116] 100 parts of coal powder, 20 parts of discarded oyster mushroom cultivation substrate and 20 parts of shell waste were dried at 75°C for 6 hours and crushed to a particle size of less than 200 μm;

[0117] The pulverized coal gasification device adopts pulverized coal entrained flow gasification technology, introduces nitrogen at a flow rate of 2.5L / s, and gasifies at 900℃ for 30min.

[0118] During the co-gasification process, the average production of H2, CH4, and CO2 per gram of mixed material was detected and calculated, which were 0.45g, 9.05g, and 1.46g, respectively. The highest calorific value of the combustible gas during the co-gasification process was recorded to be 3844.29J / L.

[0119] It can be seen from the above embodiments that the coal and biomass co-gasification scheme provided by the present invention can effectively increase the yield of H2 and CH4 in the product gas, while reducing the generation of CO2, compared with the control group; the generated H2 and CH4 can be separated and used as high-efficiency green fuels, which helps to promote the optimization of the energy structure, reduce dependence on fossil fuels, and promote the sustainable development of energy; and the components of the present invention cooperate with each other to achieve further catalysis in the coal gasification process, thereby reducing the temperature required for co-gasification, achieving energy conservation and carbon reduction, and having important significance for environmental protection.

[0120] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for co-gasification of coal and biomass, characterized in that: The following steps are involved: mixing coal, agricultural and forestry residues, fungus cultivation substrate and shell waste to obtain a mixture; The mixture is sequentially dried and crushed to obtain a crushed product; The pulverized material is co-gasified.

2. The method for co-gasification of coal and biomass according to claim 1, characterized in that: The coal is selected from one or more of coking coal, bituminous coal, lean coal, gas coal, non-caking coal, lean coal, raw coal, washed coal, peat, fat coal, lignite, long flame coal, weakly caking coal, medium caking coal, thermal coal, coal fines, candle coal or sub-bituminous coal.

3. The method for co-gasification of coal and biomass according to claim 1, characterized in that: The agricultural and forestry residues are selected from one or more of forestry residues, waste wood, wood chips, crop straws or waste crop residues.

4. The method for co-gasification of coal and biomass according to claim 3, characterized in that: The crop straw or waste crop residue comes from wheat, rice, corn, potato, rapeseed, cotton or sugarcane.

5. The method for co-gasification of coal and biomass according to claim 1, characterized in that: The mixture comprises the following components in parts by weight: 80-120 parts of coal, 40-80 parts of agricultural and forestry residues, 10-30 parts of fungus cultivation substrate, and 10-30 parts of shell waste.

6. The method for co-gasification of coal and biomass according to claim 1, characterized in that: The drying temperature is 60-90°C; The drying time is 5 to 7 hours.

7. The method for co-gasification of coal and biomass according to claim 1, characterized in that: The particle size of the crushed particles is less than 300 μm.

8. The method for co-gasification of coal and biomass according to claim 1, characterized in that: During the co-gasification process, a process gas is introduced; The process gas is nitrogen; The flow rate of the process gas is 2 to 3 L / s.

9. The method for co-gasification of coal and biomass according to claim 1, characterized in that: The co-gasification temperature is 600-900°C; The co-gasification time is 20 to 40 minutes.

10. Application of the coal and biomass co-gasification method according to any one of claims 1 to 9 in increasing the production of H2 and CH4 in product gas, reducing CO2 generation, lowering the temperature required for co-gasification or increasing the calorific value of combustible gas.