Biomass gasification and calorific value increasing system

Abstract

The utility model relates to the technical field of environment-friendly and green energy preparation, in particular to a biomass gasification and calorific value increasing system which comprises a gasification furnace, a biomass inlet and a bed material inlet are formed in the side wall of the gasification furnace, and the side wall of the gasification furnace is connected with a gasification agent mixing preheater, a plasma gun and a biogas pipeline. The gasification agent mixing preheater is provided with an oxygen pipeline and an air pipeline, the other end of the biogas pipeline is connected with a gas purification system, an outlet of the gas purification system is connected with a gas storage cabinet, an outlet of the gas storage cabinet is connected with a CO conversion system to convert CO into CO2, an outlet of the CO conversion system is connected with a decarburization system to remove CO2 in gas, and the CO2 is converted into CO2. An outlet of the decarbonization system is connected with the methanation system, so that residual CO and H2 in the fuel gas are subjected to methanation reaction, and an outlet of the methanation system is connected with the pressure regulating and odorizing system. Biomass waste is gasified to obtain biogas, high-calorific-value energy is produced, and high economic and practical values are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental protection and green energy preparation, and in particular provides a biomass gasification and calorific value enhancement system. Background Art

[0002] Among the many new technologies for biomass energy utilization, biomass gasification is one of the fastest-growing and most mature engineering technologies. Biomass gasification primarily produces combustible gases. An analysis of existing syngas purification technologies, such as adsorption, membrane separation, and oxidation, reveals that research in this area is intensifying both domestically and internationally, and a relatively mature research system has gradually emerged. However, there are also challenges that require further improvement. For example, existing technologies cannot fully meet the needs of practical applications, and issues such as high costs and complex equipment require further optimization. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a biomass gasification and calorific value enhancement system, which realizes the effective degradation and regeneration of biomass waste and alleviates the dual pressure of environment and energy.

[0004] The utility model is implemented as follows: a biomass gasification and calorific value enhancement system is provided, including a gasifier, a biomass inlet and a bed material inlet are provided on the side wall of the gasifier, a gasifier mixing preheater, a plasma gun and a biogas pipeline are connected to the side wall of the gasifier, an oxygen pipeline and an air pipeline are provided on the gasifier mixing preheater, the other end of the biogas pipeline is connected to a gas purification system, the outlet of the gas purification system is connected to a gas storage cabinet, the outlet of the gas storage cabinet is connected to a CO conversion system to convert CO into CO2, the outlet of the CO conversion system is connected to a decarbonization system to remove CO2 from the gas, the outlet of the decarbonization system is connected to a methanation system to cause the remaining CO in the gas to undergo a methanation reaction with H2, and the outlet of the methanation system is connected to a pressure regulating and odorizing system.

[0005] Preferably, a tubular pyrolyzer is provided on the outer wall of the biomass inlet, and the tubular pyrolyzer includes a steam heating pyrolyzer and an electric heating pyrolyzer; four plasma guns are provided, and the four plasma guns are evenly distributed along the circumference of the outer wall of the gasifier.

[0006] Further preferably, the gas purification system includes a water bath spray system and a desulfurization spray system connected in sequence.

[0007] Further preferably, the CO conversion system includes a gas compression system, a saturated hot water tower, a first heat exchanger, a second heat exchanger and a two-stage medium-temperature conversion furnace connected in sequence, and the catalyst used in the two-stage medium-temperature conversion furnace is a medium-temperature conversion catalyst B113 type.

[0008] Further preferably, the decarbonization system uses an MDEA aqueous solution to absorb CO2.

[0009] Further preferably, the methanation system is configured as a three-stage methanation unit, and the calorific value of the gas coming out of the methanation system is greater than 7000 kcal, and the CO content is below 5%.

[0010] Further preferably, the gas storage cabinet is also connected to a gas boiler.

[0011] More preferably, the method further comprises a biomass collection system, a biomass pretreatment system, a low-temperature vacuum drying system and a storage and batching system which are connected in sequence, and the outlet of the storage and batching system is connected to the biomass inlet.

[0012] Compared with the prior art, the advantages of the present invention are:

[0013] The utility model provides a biomass gasification and calorific value enhancement system, which adopts raw material pretreatment technology, vacuum drying technology, plasma oxygen-enriched gasification, gas composition conversion, decarbonization, methanation and other technologies to gasify biomass waste to obtain biogas, realizing the transformation of waste into treasure, producing high calorific value energy, and having great economic and practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0015] Figure 1 This is a schematic diagram of the connection structure of each module of the present utility model. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] refer to Figure 1The utility model provides a biomass gasification and calorific value enhancement system, including a gasifier 8, a biomass inlet 5 and a bed material inlet 6 are provided on the side wall of the gasifier 8, a gasifier mixing preheater 15, a plasma gun 14 and a biogas pipeline 9 are connected to the side wall of the gasifier 8, an oxygen pipeline and an air pipeline are provided on the gasifier mixing preheater 15, the other end of the biogas pipeline 9 is connected to a gas purification system 10, the outlet of the gas purification system 10 is connected to a gas storage cabinet 17, the outlet of the gas storage cabinet 17 is connected to a CO conversion system 11, which converts CO into CO2, the outlet of the CO conversion system 11 is connected to a decarbonization system 12, which removes CO2 from the gas, the outlet of the decarbonization system 12 is connected to a methanation system 13, so that the remaining CO in the gas reacts with H2 for methanation, and the outlet of the methanation system 13 is connected to a pressure regulating and odorizing system 18.

[0018] When using the biomass gasification and calorific value enhancement system provided by the present invention to gasify and enhance biomass, the processed biomass is fed into the gasifier 8 through the biomass inlet 5, and the bed material (coal gangue, shale, etc.) is fed into the gasifier 8 through the bed material inlet 6. Oxygen fed from the oxygen pipeline and air fed from the air pipeline are mixed and preheated in the gasifier mixing preheater 15. The gasifier is an oxygen-enriched gasifier with an oxygen concentration of 60%-80%. The preheated gasifier is fed into the gasifier 8 to oxygen-enrich the biomass, thereby improving the combustion efficiency of the material during combustion. In the plasma gun 14, water vapor is introduced as the working gas through a pipeline into the plasma generator. The generated water vapor plasma is used to increase the concentration of hydrogen and oxygen ions in the gasifier. Due to the high temperature, high enthalpy, and high chemical activity of the plasma, the reaction rate is accelerated, further improving the gasification effect. During the gasification process of biomass in the gasifier 8, the biogas produced passes through the biogas pipeline 9 and enters the gas purification system 10 for purification. The biogas can then enter the gas storage tank 17 for storage and standby use. The gas storage tank 17 adopts a wet gas tank and is designed with nitrogen protection. This completes the biomass gasification process. When the calorific value is increased, the gas in the gas storage tank 17 enters the CO conversion system 11, which converts most of the CO in the gas into CO2. The gas from the CO conversion system 11 enters the decarbonization system 12 to remove the CO2 in the gas. The gas then enters the methanation system to methanize the remaining CO. Finally, it enters the pressure regulation and odorization system 18 for pressure regulation and odorization. After that, it can meet the civil gas standards and be sold to the outside. The utility model provides a method for producing biomass gas and increasing its calorific value, helping to achieve carbon emission reduction goals.

[0019] The methanation system 13 in the present invention is replaced by an adsorption system. The adsorption system uses a pressure swing adsorption process to remove N2 and other impurities from the gas, and the filtered high-purity H2 is sold to the outside world. This becomes a biomass gasification hydrogen production system.

[0020] In order to heat and disperse the biomass before entering the gasifier 8, as an improvement to the technical solution, a tubular pyrolyzer 7 is provided on the outer wall of the biomass inlet 5, and the tubular pyrolyzer 7 includes a steam heating pyrolyzer and an electric heating pyrolyzer; preferably, four plasma guns 14 are provided, and the four plasma guns 14 are evenly distributed along the circumference of the outer wall of the gasifier 8.

[0021] The tubular pyrolyzer 7 can make the material reach 400°C, so that the material expands in volume instantly when entering the gasification furnace 8. The material is fully burned after dispersion, which improves the combustion efficiency, keeps the combustion temperature in the furnace at a constant high temperature, and is not prone to dead bed.

[0022] As a preferred embodiment of the gas purification system 10, the gas purification system 10 includes a water bath spray system and a desulfurization spray system connected in sequence. The gas is first subjected to water bath spraying for dust removal and cooling, and then enters the desulfurization tower for spraying with magnesium hydroxide solution for desulfurization, thereby removing impurities and pollutants in the gas.

[0023] As a specific implementation of the CO2 conversion system 11, it comprises a sequentially connected gas compression system, a saturated hot water tower, a first heat exchanger, a second heat exchanger, and a two-stage medium-temperature shift converter. The catalyst used in the two-stage medium-temperature shift converter is a B113 medium-temperature shift catalyst. Both the first and second heat exchangers recover waste heat and control gas temperature. The first heat exchanger preheats the gas entering the two-stage medium-temperature shift converter to 220°C and cools the gas outlet temperature of the second stage of the two-stage medium-temperature shift converter to 200°C. The second heat exchanger preheats the gas entering the two-stage medium-temperature shift converter to 300°C and cools the gas outlet temperature of the first stage of the two-stage medium-temperature shift converter to 350°C before returning it to the second stage of the medium-temperature shift converter.

[0024] After the gas is compressed by the gas compression system, it enters the saturated hot water tower for contact heat transfer, then enters the first and second heat exchangers for heat exchange. Once the process requirements are met, it enters the first stage of the medium-temperature shift furnace for reaction, and then enters the second stage for further reaction. After the reaction is completed, the gas passes through the first and second exchangers until it meets the process requirements and enters the next stage. Condensate water is installed between each stage as a cooling line to adjust the steam-to-gas ratio and temperature.

[0025] Preferably, the decarbonization system 12 uses an MDEA aqueous solution to absorb CO2, thereby largely removing the carbon dioxide from the fuel gas. The MDEA aqueous solution (rich solution) after absorbing carbon dioxide is heated and depressurized before being stripped and regenerated in a regeneration tower. The regenerated lean solution is cooled and heat-exchanged before being recycled, and the desorbed CO2 can be reused.

[0026] As a specific implementation method of the methanation system 13, the methanation system 13 is configured as a three-stage methanation unit, namely pre-methanation, intermediate methanation and final methanation, to ensure that carbon monoxide and hydrogen in the fuel gas undergo a methanation reaction, and the calorific value of the fuel gas coming out of the methanation system 13 is greater than 7000 kcal and the CO content is below 5%.

[0027] The gas in the gas storage tank 17 can be directly provided to the boiler for use, so the gas storage tank 17 is also connected to the gas boiler 16.

[0028] In order to pre-process different types of biomass, as an improvement to the technical solution, it also includes a biomass collection system 1, a biomass pre-processing system 2, a low-temperature vacuum drying system 3 and a storage and batching system 4 connected in sequence, and the outlet of the storage and batching system 4 is connected to the biomass inlet 5.

[0029] Biomass waste collected by biomass collection system 1 includes agricultural waste, domestic garbage, municipal sludge, and feces. In biomass pretreatment system 2, crushing, air separation, mechanical sorting, and manual sorting are the primary pretreatment processes for agricultural waste, straw, and domestic garbage. For municipal sludge and feces, thermal hydrolysis, wall crushing, and filter pressing are the primary pretreatment processes, reducing the moisture content from 80% to 60%. For coal gangue and shale, a two-stage crushing process is employed to prepare them for use as gasification bed material. After passing through biomass pretreatment system 2, the biomass waste enters low-temperature vacuum drying system 3, a low-temperature vacuum conditioning drying method for biomass materials. The dryer maintains a negative pressure environment, subjecting the material to negative pressure and rapidly drying it by reaching its boiling point under negative pressure. This improves thermal efficiency and reduces heat loss. Low-temperature vacuum drying system 3 uses a steam evacuator to achieve negative pressure within the dryer, simultaneously removing a large amount of moisture during vacuuming, reducing the material's moisture content to below 20%. The dried materials enter the storage and batching system 4, which is designed as a fully automatic unmanned three-dimensional silo, and a nitrogen protection system is installed in the silo.

[0030] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A biomass gasification and calorific value enhancement system, characterized in that: The invention comprises a gasifier (8), wherein a biomass inlet (5) and a bed material inlet (6) are provided on the side wall of the gasifier (8), a gasifying agent mixing preheater (15), a plasma gun (14) and a biogas pipeline (9) are connected to the side wall of the gasifier (8), an oxygen pipeline and an air pipeline are provided on the gasifying agent mixing preheater (15), the other end of the biogas pipeline (9) is connected to a gas purification system (10), the outlet of the gas purification system (10) is connected to a gas storage cabinet (17), the outlet of the gas storage cabinet (17) is connected to a CO conversion system (11) for converting CO into CO2, the outlet of the CO conversion system (11) is connected to a decarbonization system (12) for removing CO2 from the gas, the outlet of the decarbonization system (12) is connected to a methanation system (13) for causing the remaining CO in the gas to undergo a methanation reaction with H2, and the outlet of the methanation system (13) is connected to a pressure regulating and odorizing system (18).

2. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: A tubular pyrolyzer (7) is provided on the outer wall of the biomass inlet (5), and the tubular pyrolyzer (7) includes a steam heating pyrolyzer and an electric heating pyrolyzer; four plasma guns (14) are provided, and the four plasma guns (14) are evenly distributed along the circumference of the outer wall of the gasifier (8).

3. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: The gas purification system (10) comprises a water bath spray system and a desulfurization spray system which are connected in sequence.

4. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: The CO conversion system (11) comprises a gas compression system, a saturated hot water tower, a first heat exchanger, a second heat exchanger and a two-stage medium-temperature conversion furnace connected in sequence, wherein the catalyst used in the two-stage medium-temperature conversion furnace is a medium-temperature conversion catalyst B113 type.

5. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: The decarbonization system (12) uses an MDEA aqueous solution to absorb CO2.

6. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: The methanation system (13) is a three-stage methanation unit arrangement, and the calorific value of the gas coming out of the methanation system (13) is greater than 7000 kcal, and the CO content is below 5%.

7. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: The gas storage cabinet (17) is also connected to a gas boiler (16).

8. The biomass gasification and calorific value enhancement system according to claim 1, characterized in that: The invention also comprises a biomass collection system (1), a biomass pretreatment system (2), a low-temperature vacuum drying system (3) and a storage and batching system (4) which are connected in sequence, and the outlet of the storage and batching system (4) is connected to the biomass inlet (5).

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