Biomass gasification furnace and biomass gasification system

Abstract

The utility model discloses a biomass gasification furnace and a biomass gasification system, and relates to the technical field of biomass gasification, the biomass gasification furnace provided by the utility model comprises a gasification chamber and a premixing chamber which are communicated; the burner is communicated with the premixing chamber so as to convey materials into the premixing chamber, the burner comprises a first gas path and / or a second gas path which are / is communicated with the premixing chamber, the first gas path is used for introducing a first gasifying agent into the premixing chamber, the second gas path is used for introducing a second gasifying agent into the premixing chamber, and the premixing chamber is used for mixing the materials with the first gasifying agent and / or the second gasifying agent. According to the biomass gasifier provided by the utility model, the first gasifying agent and / or the second gasifying agent flow into the premixing chamber through the first gas path and / or the second gas path, and mixed materials are fully mixed through the disturbance of gas flow.

Description

Technical Field

[0001] The utility model relates to the technical field of biomass gasification, in particular to a biomass gasifier and a biomass gasification system. Background Art

[0002] The existing biomass gasification technologies mainly include fixed-bed gasification, fluidized-bed gasification, and entrained-flow bed gasification, etc. However, both fixed-bed gasification and fluidized-bed gasification have problems such as high tar content in the syngas and low carbon conversion rate. The entrained-flow bed gasification method uses biomass powder as raw material and sprays it into the gasifier together with the gasifying agent. The reaction temperature is very high, and the ash is discharged in a molten state.

[0003] The advantages of the entrained-flow bed gasification method are large gasification intensity, wide fuel adaptability, no tar, and high carbon conversion rate. However, for an entrained-flow bed, especially a pressurized entrained-flow bed, in order to reduce the amount of inert gas carrying the fuel and increase the solid-gas ratio of transportation, a dense-phase transportation technology needs to be adopted. And when biomass is applied to an entrained-flow bed, it needs to be crushed into powders with a particle size of <1mm. However, due to the fibrous structure of biomass, such powders are prone to adhesion and blockage of pipelines, and the dense-phase transportation technology for pulverized coal cannot be used to transport them into the furnace. Although the baked biomass powder can be transported in a dense phase, the investment in baking equipment is high, the energy consumption is large, and the economy is very poor. In the current existing technologies, a screw feeding-into-furnace technology is adopted to solve the above problems of biomass powder feeding into the furnace, but the screw feeding-into-furnace technology has the problem that the biomass powder and the gasifying agent cannot be fully mixed and gasified.

[0004] Therefore, when the entrained-flow bed gasification method adopts the screw feeding-into-furnace technology, how to ensure the full mixing and gasification of biomass powder and the gasifying agent is a technical problem that needs to be solved by those skilled in the art at present. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a biomass gasifier and a biomass gasification system. The biomass gasifier provided by the utility model is used to ensure the full mixing and gasification of biomass powder and the gasifying agent when the entrained-flow bed gasification method adopts the screw feeding-into-furnace technology.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A biomass gasifier, comprising:

[0008] A gasification chamber and a premixing chamber that are communicated;

[0009] A burner, which is communicated with the premixing chamber to convey materials into the premixing chamber. The burner includes a first gas path and / or a second gas path communicated with the premixing chamber. The first gas path is used to introduce a first gasifying agent into the premixing chamber, and the second gas path is used to introduce a second gasifying agent into the premixing chamber. The premixing chamber is used to mix the materials, the first gasifying agent and / or the second gasifying agent.

[0010] In the case of adopting the above technical solution, before the biomass powder in the burner is conveyed to the gasification chamber, the first gasifying agent flows into the premixing chamber through the first gas path, and the second gasifying agent flows into the premixing chamber through the second gas path. Through the air flow disturbance of the first gasifying agent and / or the second gasifying agent in the premixing chamber, the first gasifying agent and / or the second gasifying agent are fully mixed with the biomass powder in the premixing chamber, ensuring that the first gasifying agent and / or the second gasifying agent and the biomass powder have good mixing properties before entering the gasification chamber.

[0011] Optionally, in the above biomass gasification furnace, the burner includes a material conveying pipe and a conveying shaft. The material conveying pipe is communicated with the premixing chamber. The conveying shaft sequentially penetrates through the material conveying pipe and the premixing chamber, and the conveying shaft is provided with a first cavity and a first gasifying agent outlet communicated with the first cavity. The first gasifying agent outlet is located in the premixing chamber, so that the conveying shaft forms the first gas path. In this way, the materials of the burner are conveyed to the premixing chamber through the material conveying pipe, while the first gasifying agent is conveyed to the premixing chamber through the first cavity and the first gasifying agent outlet in the conveying shaft, realizing the conveying of the materials and the first gasifying agent. The overall structure is compact and simple, and the reliability is high.

[0012] Optionally, in the above biomass gasification furnace, there are a plurality of first gasifying agent outlets, and they are spirally and spacedly distributed on the circumferential surface of the conveying shaft along the axial direction of the conveying shaft. In this way, by arranging the first gasifying agent outlets on the circumferential surface of the conveying shaft in a spiral manner, the air flow direction when the first gasifying agent is sprayed into the premixing chamber has a preset spiral direction, so as to enhance the air flow disturbance ability in the premixing chamber and improve the mixing ability.

[0013] Optionally, in the above biomass gasification furnace, the conveying shaft can rotate around its own axis. A spiral blade is arranged on the section of the conveying shaft located inside the material conveying pipe and extends outward. The spiral blade and the spiral distribution of the first gasifying agent outlets on the conveying shaft have the same spiral direction. In this way, the strength of the spiral air flow of the first gasifying agent can be enhanced, and the mixing ability can be improved. At the same time, the conveying shaft drives the spiral blade to convey the biomass powder and conveys the biomass powder to the premixing chamber. Therefore, the conveying shaft integrates the functions of conveying the biomass powder and the first gasifying agent at the same time, significantly improving the compactness of the structure and also facilitating the efficient progress of the feeding work.

[0014] Optionally, in the above biomass gasifier, the section of the conveying shaft provided with the first gasifying agent outlet includes a cylindrical section and a conical section. The conical section is closer to the gasification chamber than the cylindrical section, and along the direction of the conveying shaft extending towards the gasification chamber, the diameter of the conical section gradually increases. In this way, a conical section is provided in the section of the conveying shaft where the first gasifying agent outlet is arranged. The conical section with a gradually increasing diameter reduces the cross-sectional area between the conical section and the inner wall of the premixing chamber, thereby strengthening the air flow disturbance intensity of the first gasifying agent and the second gasifying agent in the premixing chamber, and further enhancing the ability to uniformly mix the first gasifying agent, the second gasifying agent, and the biomass powder; at the same time, it also increases the air flow velocity of the mixed material entering the gasification chamber and reduces the possibility of the flame in the gasification chamber backflowing to the burner.

[0015] Optionally, in the above biomass gasifier, disturbance bars are also provided on the section of the conveying shaft where the first gasifying agent outlet is arranged. In this way, the disturbance bars stir the biomass powder as the conveying shaft rotates to break up the caking or adhesion in the biomass powder, ensuring that the biomass powder maintains good dispersibility. At the same time, the stirring of the biomass powder is beneficial to promoting the uniformity of the mixing of the first gasifying agent, the second gasifying agent, and the biomass powder.

[0016] Optionally, in the above biomass gasifier, the burner includes a second gasifying agent gas chamber. The second gasifying agent gas chamber surrounds the outside of the material conveying pipe. The second gasifying agent gas chamber is connected to the premixing chamber. The second gasifying agent gas chamber is provided with a second gasifying agent inlet and guide vanes. The air flow direction of the second gasifying agent flowing into the premixing chamber is adjusted through the guide vanes, so that the second gasifying agent gas chamber forms the second gas path. In this way, the second gasifying agent flows into the second gasifying agent gas chamber through the second gasifying agent inlet, and then the guide vanes in the second gasifying agent gas chamber can adjust the swirling direction of the second gasifying agent sprayed into the premixing chamber, thereby realizing that the second gasifying agent can flow into the premixing chamber in a preset swirling direction and enhancing the air flow disturbance in the premixing chamber.

[0017] Optionally, in the above biomass gasifier, the swirling direction of the air flow in the first gas path is opposite to the swirling direction of the air flow in the second gas path. In this way, the swirling direction of the air flow of the first gasifying agent flowing into the premixing chamber is opposite to the swirling direction of the air flow of the second gasifying agent, thereby further enhancing the air flow disturbance in the premixing chamber through the first gasifying agent and the second gasifying agent, and further promoting the sufficient mixing of the first gasifying agent, the second gasifying agent, and the biomass powder in the premixing chamber, ensuring that the first gasifying agent, the second gasifying agent, and the biomass powder have good mixing properties before entering the gasification chamber.

[0018] Optionally, in the above biomass gasifier, the inner wall of the premixing chamber includes an inclined wall, and along the direction of the conveying axis extending towards the gasification chamber, the distance between the inclined wall and the conveying pipe gradually decreases, so that an annular gap between the inclined wall and the conveying axis forms a material dropping port. In this way, an inclined wall extending obliquely towards the conical section is provided on the inner wall of the premixing chamber, further reducing the cross-sectional area between the conical section and the inner wall of the corresponding premixing chamber, further increasing the flow velocity of the first gasifying agent and the second gasifying agent in the premixing chamber, so as to improve the uniform mixing of the first gasifying agent, the second gasifying agent and the biomass powder. At the same time, the material dropping port formed by the inclined wall and the conical section also increases the gas flow velocity of the mixed material entering the gasification chamber, reducing the possibility of the flame in the gasification chamber backfiring into the burner, playing a role in isolating the backfire.

[0019] Optionally, in the above biomass gasifier, the burner further includes a third gas path, the third gas path includes a third gas path chamber communicated with the premixing chamber, the third gas path chamber is provided with an air flow guiding mechanism, and through the air flow guiding mechanism, the air flow direction flowing into the premixing chamber is the same as the air flow direction of the second gasifying agent flowing into the premixing chamber. In this way, when the pressure in the gasification chamber reaches 3 Mpa - 6 Mpa and the pressure in the gasification chamber of the gasifier is relatively high, purified synthesis gas can be conveyed to the premixing chamber through the third gas path to increase the gas volume in the premixing chamber. Then, without adjusting the gas flow rate flowing into the gasification chamber, the flow rate flowing into the gasification chamber can be increased, thereby further reducing the risk of blockage during the process of the material entering the gasification chamber from the premixing chamber. And during the process of the synthesis gas flowing into the premixing chamber through the third gas path, through the air flow guiding mechanism, the flow direction of the synthesis gas in the premixing chamber is the same as the flow direction of the second gasifying agent entering the premixing chamber, avoiding weakening the swirling intensity of the air flow in the premixing chamber due to the opposite flow directions of the synthesis gas and the second gasifying agent, which is likely to cause the problem of material blockage.

[0020] A biomass gasification system includes the biomass gasifier as described in any one of the above. The biomass gasification system provided by the present invention has all the technical effects of the above biomass gasifier due to having the above biomass gasifier, and will not be elaborated herein again.

[0021] Optionally, in the above biomass gasification system, a spiral conveying part is further included. The spiral conveying part includes a hopper unit, a feeding control unit and a spiral conveying unit that are sequentially communicated. The spiral conveying unit is communicated with the burner, and the feeding control unit controls the conveying amount of the material from the hopper unit into the spiral conveying unit. In this way, by setting the feeding control unit, the conveying amount of the spiral conveying part to the burner can be accurately controlled, and an appropriate amount of biomass powder can be conveyed for the mixing of the first gasifying agent, the second gasifying agent and the biomass powder in the premixing chamber, ensuring the smooth operation of the mixing of the first gasifying agent, the second gasifying agent and the biomass powder. Description of the Drawings

[0022] The drawings described herein are used to provide a further understanding of the present utility model and form a part of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation of the present utility model. In the drawings:

[0023] Figure 1 is an assembly schematic diagram of a gasifier disclosed in an embodiment of the present utility model;

[0024] Figure 2 is a structural schematic diagram of a burner disclosed in an embodiment of the present utility model;

[0025] Figure 3 is a structural schematic diagram of a cylindrical section and a conical end disclosed in an embodiment of the present utility model;

[0026] Figure 4 is a structural schematic diagram of a burner disclosed in another embodiment of the present utility model;

[0027] Figure 5 is a structural schematic diagram of a biomass gasification system disclosed in an embodiment of the present utility model.

[0028] Reference Numerals:

[0029] 100 is a screw conveyor section, 110 is a hopper, 120 is a variable pressure hopper, 130 is a high-pressure hopper, 140 is a vibration module, 150 is a flap valve, 160 is a screw conveyor, 170 is a star feeder;

[0030] 200 is a gasifier, 210 is a gasification chamber, 220 is a premixing chamber, 230 is a retractable ignition torch;

[0031] 300 is a burner, 310 is a material conveying pipe, 320 is a conveying shaft, 321 is a first gasifier outlet, 322 is a cylindrical section, 323 is a conical section, 324 is a disturbance strip, 325 is a first gasifier inlet. 330 is a spiral blade, 340 is a second gasifier gas chamber, 341 is a second gasifier inlet, 342 is a guide blade, 350 is a drive motor, 360 is a bearing housing, 370 is a rotary joint, 380 is a third gas path chamber, 381 is an air inlet;

[0032] 400 is a biomass crushing device;

[0033] 10 is a water quench chamber, 20 is a waste heat boiler, 30 is a syngas purification device, 40 is a high-pressure slag hopper, 50 is a variable pressure slag hopper, 60 is a slag hopper, 70 is a shut-off valve. Detailed Embodiments

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present utility model more clear and understandable, the present utility model 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 utility model and are not used to limit the present utility model.

[0035] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0036] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless otherwise specifically defined. The meaning of "several" is one or more, unless otherwise specifically defined.

[0037] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present utility model.

[0038] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0039] The core of the present utility model is to provide a biomass gasifier, which is used to ensure the full mixing and gasification of biomass powder and gasifying agent when the entrained flow gasification method adopts the spiral feeding into the furnace technology;

[0040] Another core of the present utility model is to provide a biomass gasification system having the above biomass gasifier.

[0041] Such as Figure 1 AndFigure 5 As shown in the figure, an embodiment of the present utility model discloses a biomass gasifier 200, which includes a connected gasification chamber 210, a premixing chamber 220, and a burner 300. Among them, the biomass powder formed after the biomass raw material is crushed is transported to the burner 300 through the screw conveyor 100. While the biomass powder is being transported to the burner 300, the first gasifying agent and the second gasifying agent respectively flow into the premixing chamber 220 in the gasifier 200 through the first gas path and the second gas path in the burner 300. Through the airflows in the first gas path and the second gas path, the first gasifying agent, the second gasifying agent, and the biomass powder are promoted to be fully mixed in the premixing chamber 220 to ensure that the mixture entering the gasification chamber 210 in the gasifier 200 has good mixing properties and improve the gasification reaction efficiency of the gasification chamber 210.

[0042] As Figure 2 and Figure 3 As shown in the figure, the burner 300 in this embodiment is a spiral burner. The burner 300 includes a material conveying pipe 310 and a conveying shaft 320. One end of the material conveying pipe 310 extends into the premixing chamber 220 of the gasifier 200, and the conveying shaft 320 passes through the material conveying pipe 310 and extends into the premixing chamber 220. A first cavity is provided inside the conveying shaft 320, and one end of the conveying shaft 320 is connected to the first gasifying agent inlet 325 through a rotary joint 370. The other end of the conveying shaft 320 is provided with a first gasifying agent outlet 321, and the first gasifying agent outlet 321 is located in the premixing chamber 220. Thus, the first gasifying agent flows into the first cavity through the first gasifying agent inlet 325 and then is sprayed into the premixing chamber 220 to participate in the mixing of the biomass powder.

[0043] It can be understood that the burner 300 can be a spiral burner. In some other embodiments, the burner 300 can also adopt other forms. For example, the power for transporting the biomass material is provided by a plunger, air flow, etc., or the biomass material enters the premixing chamber through the burner 300 only under the action of gravity. The present utility model does not limit the specific type of the burner 300 as long as it can realize transporting the biomass material, the first gasifying agent, and the second gasifying agent to the premixing chamber for mixing.

[0044] The biomass raw materials made into biomass powder may include biomass briquettes, biomass pellets or biomass bulk materials in various shapes. The first gasifying agent may be water vapor, carbon dioxide, or a mixture of water vapor and carbon dioxide, while the second gasifying agent may be oxygen, a mixture of oxygen and carbon dioxide, or a mixture of oxygen and water vapor. The main reactions of the first gasifying agent with biomass are endothermic reactions, and the reaction equations are C + H2O = CO + H2 and C + CO2 = 2CO respectively, and the absorbed heat is 131 kJ / mol and 172 kJ / mol respectively. The main reactions of the second gasifying agent with biomass are exothermic reactions, and the reaction equations are: C + O2 = CO2 and C + 0.5O2 = CO respectively, and the released heat during the reaction is 394 kJ / mol and 111 kJ / mol respectively. It can be understood that in actual production, appropriate gasifying agents can be selected according to the reaction needs. Only one gasifying agent can be used, or multiple gasifying agents can be used. The first gas path and the second gas path can introduce the same gasifying agent or different gasifying agents. The present invention does not limit this.

[0045] In order to enable the airflow of the first gasifying agent injected into the premixing chamber 220 to have a preset swirling direction, there are multiple first gasifying agent outlets 321, and along the axial extension direction of the conveying shaft 320, each first gasifying agent outlet 321 is spirally and spacedly distributed on the circumferential surface of the conveying shaft 320, thereby enabling the first gasifying agent injected into the premixing chamber 220 to have a preset airflow swirling direction, forming the first gas path. The first gasifying agent outlet 321 can be a circular or grooved hole, and the corresponding diameter size or width size range can be 3 mm to 12 mm. In a specific embodiment, the inner diameter size of the material conveying pipe 310 is D, the pitch S of the spiral formed by the first gasifying agent outlets 321 can be 0.4D to 0.6D, and the number of first gasifying agent outlets 321 in one pitch S can be 6 to 24. The total length of all the first gasifying agent outlets 321 arranged along the axial direction of the conveying shaft 320 can be set to be not less than 1.5 times the pitch. Since the main reaction of the first gasifying agent with biomass is an endothermic reaction, it can ensure a low temperature at the outlet of the burner 300 and at the same time play a role in preventing flashback. And in a specific embodiment, the airflow velocity ejected from the first gasifying agent outlet 321 is 50 m / s - 100 m / s to form a strong spiral airflow and strengthen the mutual mixing between the biomass powder, the first gasifying agent and the second gasifying agent.

[0046] Such as Figure 2 And Figure 3As shown, the conveying shaft 320 can rotate about its own axis. A spiral blade 330 is disposed extending outwardly on the section of the conveying shaft 320 located inside the material conveying pipe 310. The material conveying pipe 310 is connected to the spiral conveying part 100. Thus, when the spiral conveying part 100 conveys biomass powder into the material conveying pipe 310, the driving motor 350 drives the conveying shaft 320 mounted on the bearing block 360 to rotate. The spiral blade 330 provided on the conveying shaft 320 rotates synchronously with the conveying shaft 320 to convey the biomass powder towards the premixing chamber 220, thereby forming a material conveying section. Moreover, the spiral blade 330 and the first gasifying agent outlet 321 have the same spiral direction in the spiral distribution on the conveying shaft 320. By making the rotation direction of the conveying shaft 320 the same as the spiral direction of the first gasifying agent outlet 321, the intensity of the spiral air flow of the first gasifying agent is enhanced. In addition, the conveying shaft 320 integrates the functions of conveying biomass powder and conveying the first gasifying agent, significantly improving the compactness of the structure, enhancing the simplicity of the structure, and thus also facilitating the efficient operation of the feeding work.

[0047] As Figure 3 shown, the section of the conveying shaft 320 where the first gasifying agent outlet 321 is provided further includes a cylindrical section 322 and a conical section 323, wherein the conical section 323 is closer to the gasification chamber 210 of the gasifier 200 than the cylindrical section 322. Along the extending direction of the conveying shaft 320 towards the gasification chamber 210, the diameter of the conical section 323 gradually increases, such that along the direction from the cylindrical section 322 to the end of the conical section 323, the cross-sectional area of the gap between the section of the conveying shaft 320 provided with the spiral first gasifying agent outlet 321 and the inner wall of the premixing chamber 220 gradually decreases, and the available space on the inner wall of the premixing chamber 220 gradually becomes smaller. The upper cylindrical section 322 has a larger space to ensure the space required for the mixing of the first gasifying agent, the second gasifying agent, and the biomass powder, while the lower conical section 323 has a reduced space to strengthen the air flow disturbance intensity of the first gasifying agent and the second gasifying agent in the premixing chamber 220, thereby further enhancing the ability to uniformly mix the first gasifying agent, the second gasifying agent, and the biomass powder; at the same time, it also increases the air flow velocity of the mixed material entering the gasification chamber and reduces the possibility of the flame in the gasification chamber backfiring to the burner.

[0048] In a specific embodiment, the cone angle of the conical section 323 ranges from 5° to 30° to reduce the problem of biomass powder blockage. The length of the conical section 323 is L3, and L3 can be set to 0.5D to 1D. If the extension length is too short, the mixing effect will be affected, while if the extension is too long, the premixing chamber 220 will be too long, resulting in too high an overall structure and unable to promote the mixing of biomass powder and gasifying agent. In addition, the conical section 323 can be made of alloy steel material with high temperature resistance. The length of the cylindrical section 322 is L2, and L2 can also be set to 0.5D to 1D. Meanwhile, along the direction from the cylindrical section 322 to the conical section 323, the distance between the first gasifying agent outlet 321 on the cylindrical section 322 and the material conveying pipe 310 is L1, and L1 can be set to 0.1D to 0.25D. In addition, a plug plate is provided at the bottom of the conical section 323. The body of the conical section 323 and the plug plate can be welded or integrally cast to ensure that the first gasifying agent does not discharge from the bottom of the conical section 323.

[0049] As Figure 3 shown, a disturbing strip 324 is also provided on the section of the conveying shaft 320 where the first gasifying agent outlet 321 is provided. The disturbing strip 324 can be provided with one or multiple. When multiple disturbing strips 324 are provided, the disturbing strips 324 can be spaced apart on the section of the conveying shaft 320 where the first gasifying agent outlet 321 is provided. And one disturbing strip 324 or multiple disturbing strips 324 can be provided on the cylindrical section 322 or on the conical section 323. Those skilled in the art can set the number and arrangement mode of the disturbing strips 324 according to actual needs. The distance from the connection of the disturbing strip 324 to the cylindrical section 322 to the material conveying pipe 310 is H1, and the range of H1 can be 0.4D to 0.6D. The length of the disturbing strip 324 can be set to 0.25D to 0.5D. And an inclined angle is provided between the plane perpendicular to the axis of the cylindrical section 322 of the disturbing strip 324, so that the disturbing strip 324 extends obliquely in the material conveying direction, and the range of the inclined angle is 5° to 10°. Then, when the conveying shaft 320 rotates, the disturbing strip 324 is synchronously driven to rotate. The rotating disturbing strip 324 stirs the biomass powder, and the lumps or adhesions in the biomass powder are broken up by the disturbing strip 324, so as to ensure that the biomass powder maintains good dispersibility, which is beneficial to the gasification process of the biomass powder. At the same time, the stirring of the biomass powder is beneficial to promoting the uniformity of the mixing of the first gasifying agent, the second gasifying agent and the biomass powder.

[0050] As Figure 2As shown in the figure, the burner 300 includes a second gasifier gas chamber 340 communicating with the premixing chamber 220, and the second gasifier gas chamber 340 surrounds the outside of the material conveying pipe 310. The second gasifier gas chamber 340 is provided with a second gasifier inlet 341 and a guide vane 342. After the second gasifier flows into the second gasifier gas chamber 340 through the second gasifier inlet 341, the second gasifier in the second gasifier gas chamber 340 then flows into the premixing chamber 220. When the second gasifier in the second gasifier gas chamber 340 flows into the premixing chamber 220, the guide vane 342 of the second gasifier gas chamber 340 adjusts the flow direction of the second gasifier, so that the second gasifier has a preset swirling airflow when entering the premixing chamber 220, ensuring that there is a strong airflow disturbance in the premixing chamber 220 and promoting the mixing of the first gasifier, the second gasifier and the biomass powder.

[0051] Furthermore, the swirling direction of the airflow in the first gas path is set to be opposite to that in the second gas path. The airflow with opposite rotations can significantly enhance the disturbance of the airflow in the premixing chamber 220, further promoting the sufficient mixing of the first gasifier, the second gasifier and the biomass powder in the premixing chamber 220, and ensuring that the first gasifier, the second gasifier and the biomass powder have good mixing before entering the gasification chamber 210.

[0052] Furthermore, the inner wall of the premixing chamber 220 is provided with an inclined wall. Along the extending direction of the conical section 323 towards the gasification chamber 210, the distance between the inclined wall and the conical section 323 gradually decreases, and the annular gap surrounded by the inclined wall and the conical section 323 forms a material dropping port, so that the mixture in the premixing chamber 220 enters the gasification chamber 210 of the gasifier 200 through the material dropping port. By providing an inclined wall on the inner wall of the premixing chamber 220 that extends obliquely towards the conical section 323, the cross-sectional area between the conical section 323 and the corresponding inner wall of the premixing chamber 220 is further reduced, further increasing the flow velocity of the first gasifier and the second gasifier in the premixing chamber 220 to improve the uniform mixing of the first gasifier, the second gasifier and the biomass powder. At the same time, the material dropping port formed by the inclined wall and the conical section 323 also increases the airflow velocity entering the gasification chamber 210, reducing the problem of the flame in the gasification chamber 210 backfiring into the burner 300 and playing a role in isolating the backfire.

[0053] As Figure 4As shown, when the pressure in the gasification chamber 210 of the gasifier 200 reaches 3 Mpa - 6 Mpa, and the pressure in the gasification chamber 210 is relatively high, the amount of gas entering the gasification chamber 210 decreases. On the premise of ensuring that the flow rate of the gas entering the gasification chamber 210 from the premixing chamber 220 remains unchanged to ensure that the problem of flashback does not occur, it is necessary to reduce the cross-sectional area of the material dropping port of the premixing chamber 220, and the reduced material dropping port is prone to being blocked by biomass powder. Therefore, a third gas path is also provided in the burner 300 of the biomass gasifier provided in this embodiment. The third gas path chamber 380 of the third gas path surrounds the outside of the material conveying pipe 310 and is adjacent to the second gasification agent gas chamber 340. The third gas path chamber 380 is provided with an air inlet 381 and an exhaust port. The third gas path chamber 380 is connected to the premixing chamber 220 through the exhaust port, and an air flow guiding mechanism for adjusting the air flow direction is also provided in the third gas path chamber 380, so that the gas passing through the third gas path chamber 380 is conveyed into the premixing chamber 220 according to a preset flow direction. Thus, the finally purified synthesis gas can flow into the third gas path chamber 380 through the air inlet 381, and then return to the premixing chamber 220 through the exhaust port of the third gas path chamber 380, increasing the amount of gas in the premixing chamber 220. Therefore, without reducing the cross-sectional area of the material dropping port of the premixing chamber 220, while ensuring that the gas flow rate into the gasification chamber 210 does not cause the problem of flashback, the problem of biomass powder blocking the material dropping port is reduced. Moreover, through the air flow guiding mechanism, the rotation direction of the gas flowing from the third gas path chamber 380 into the premixing chamber 220 is the same as the rotation direction of the second gasification agent in the premixing chamber 220, avoiding the problem that the air flow is chaotic due to the opposite rotation directions of the two, which is prone to causing the blockage of the material dropping port. In a specific embodiment, the air flow guiding mechanism in the third gas path chamber 380 can also adopt guide vanes 342, and the amount of synthesis gas introduced into the third gas path chamber 380 is 0.5 - 1 times the amount of the finally produced synthesis gas. The third gas path chamber 380 and the second gasification agent gas chamber 340 can be connected into an integral structure by welding.

[0054] In a specific embodiment, the air flow velocity of the air entering the gasification chamber 210 of the gasifier 200 through the material dropping port is not less than 20 m / s. Thus, by limiting the air flow velocity of the air entering the gasification chamber 210 of the gasifier 200 through the material dropping port, the problem of the flame in the gasification chamber 210 flushing back to the burner 300 is further ensured to be reduced.

[0055] The embodiment of the present invention also discloses a biomass gasification system, including a biomass gasifier. Since this biomass gasification system has the above-mentioned biomass gasifier, it has all the technical effects of the above-mentioned biomass gasifier, and will not be elaborated herein.

[0056] As Figure 5As shown in the figure, the biomass gasification system provided in this embodiment includes a screw conveying unit 100. The screw conveying unit 100 includes a hopper unit, a feeding control unit, and a screw conveying unit. The hopper unit is provided with a hopper 110, a variable-pressure hopper 120, a high-pressure hopper 130, and a vibration module 140. The hopper 110, the variable-pressure hopper 120, and the high-pressure hopper 130 are sequentially connected along the biomass powder conveying direction. And an insertion plate valve 150 is provided between the hopper 110 and the variable-pressure hopper 120, and between the variable-pressure hopper 120 and the high-pressure hopper 130. The biomass raw material is crushed into biological powder by a biomass crushing device 400. The particle diameter of the biological powder should be less than 1 mm. The biological powder is first conveyed into the hopper 110. During this process, the hopper 110 and the variable-pressure hopper 120 are separated by the insertion plate valve 150. After the hopper 110 is filled with biomass powder, after receiving the corresponding process instruction, the hopper 110 and the variable-pressure hopper 120 are conducted through the insertion plate valve 150, so that the biomass powder in the hopper 110 flows into the variable-pressure hopper 120. At this time, both the hopper 110 and the variable-pressure hopper 120 are in an atmospheric pressure state. After the biomass in the hopper 110 enters the variable-pressure hopper 120, at this time, the hopper 110 and the variable-pressure hopper are isolated from each other again through the insertion plate valve 150, and the variable-pressure hopper 120 and the high-pressure hopper 130 are also in an isolated state. Then, the variable-pressure hopper 120 is pressurized so that the pressure value of the variable-pressure hopper 120 is higher than the pressure value of the high-pressure hopper 130. When the exceeded range is 0 - 10 Kpa, the pressurization of the variable-pressure hopper 120 is stopped. When there is no material in the high-pressure hopper 130 or the biomass powder is lower than the preset value, the variable-pressure hopper 120 and the high-pressure hopper 130 are conducted through the operation of the insertion plate valve 150, so that the biomass powder in the variable-pressure hopper 120 falls into the high-pressure hopper 130. After all the biomass powder enters the high-pressure hopper 130, the variable-pressure hopper 120 and the high-pressure hopper 130 are isolated from each other through the insertion plate valve 150 again. The biomass powder in the high-pressure hopper 130 is quantitatively conveyed to the screw conveying unit by the feeding control unit. Thus, the screw conveying unit conveys a quantitative amount of biomass powder to the burner 300 to convey an appropriate amount of biomass powder for the mixing of the first gasifying agent, the second gasifying agent, and the biomass powder in the premixing chamber 220, ensuring the smooth operation of the mixing of the first gasifying agent, the second gasifying agent, and the biomass powder. And vibration modules 140 are provided between the feeding control unit and the high-pressure hopper 130, and between the feeding control unit and the screw conveying unit. Through the vibration action of the vibration module 140, the problem of blockage of biomass powder in the pipeline during the conveying process is prevented.

[0057] In a specific embodiment, an inflation device is provided in the high-pressure hopper 130. The high-pressure hopper 130 is inflated and pressurized through the inflation device. The pressure of the high-pressure hopper 130 needs to be greater than the pressure in the gasifier 200, and the range of the pressure difference is 1 KPa to 10 KPa. This not only reduces the occurrence of gas in the gasification chamber 210 backflowing into the burner 300, but also the slightly higher pressure of the high-pressure hopper 130 than that in the gasifier 200 can reduce the amount of ineffective gas entering the gasifier 200, thereby reducing the influence of the ineffective gas on the temperature reduction in the gasifier 200. The gas filled can be CO2. The pressure range in the gasification chamber 210 is 1 MPa to 6 MPa, and the temperature range is 1000 °C to 1600 °C. The gasification chamber 210 of the gasifier 200 is ignited by the retractable igniter 230. The biomass and the gasifying agent are quickly mixed when they just enter the gasifier 200, and at the same time, a gasification reaction quickly occurs under high temperature and high pressure. The residence time of the biomass powder in the furnace is ≥4 s, and the ash in the biomass forms a molten slag at high temperature.

[0058] In another specific embodiment, the screw conveying unit uses a screw conveyor 160 to convey the biomass powder. The rotation speed of the conveying shaft 320 in the burner 300 is 3 to 4 times the rotation speed of the rotating shaft in the screw conveyor 160. The conveying shaft 320 with a higher rotation speed ensures that the biomass powder in the burner 300 or the biomass powder output from the burner 300 does not agglomerate or adhere, and further ensures that the biomass powder can be fully contacted and mixed with the first gasifying agent and the second gasifying agent. Specifically, the rotation speed of the rotating shaft in the screw conveyor 160 can be 0 to 100 r / min, or those skilled in the art can set it according to actual needs.

[0059] The material control unit uses a star feeder 170. Using the star feeder 170 not only realizes the precise control of the conveying amount of the biomass powder, but also the star feeder 170 has a smaller through-flow cross-sectional area, so it can reduce the amount of ineffective gas entering the screw conveying section 100, thereby further avoiding the influence of reducing the reaction temperature due to a large amount of ineffective gas being conveyed into the gasifier 200. At the same time, the star feeder 170 ensures a stable quantitative conveying of the biomass powder, thus solving the problem that the temperature of the gasifier 200 runs unstably and the composition and yield of the synthesis gas constantly change due to the uneven feeding during the screw conveying process.

[0060] Such as Figure 5As shown in the figure, the biomass gasification system provided in this embodiment further includes a water quench chamber 10, a waste heat boiler 20, a syngas purification device 30, a high-pressure slag hopper 40, a variable-pressure slag hopper 50, and a slag hopper 60. Among them, the syngas in the gasifier 200 flows through the water quench chamber 10, the waste heat boiler 20, and the syngas purification device 30 in sequence and finally produces the required purified syngas. Atomized water is introduced into the water quench chamber 10 to lower the temperature of the syngas below the ash fusion temperature to prevent ash from sticking to the heating surface of the waste heat boiler 20. The waste heat boiler 20 is mainly used to recover the heat of the syngas, and the syngas purification device is mainly used to purify dust, tar, acidic substances, etc. in the syngas. The molten slag generated in the gasifier 200 is discharged after passing through the high-pressure slag hopper 40, the variable-pressure slag hopper 50, and the slag hopper 60 in sequence, and a switching valve 70 is provided between the high-pressure slag hopper 40 and the variable-pressure slag hopper 50, and between the variable-pressure slag hopper 50 and the slag hopper 60 to realize the conduction or cut-off between the high-pressure slag hopper 40 and the variable-pressure slag hopper 50, and between the variable-pressure slag hopper 50 and the slag hopper.

[0061] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0062] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A biomass gasifier, characterized in that: include: A gasification chamber and a premixing chamber connected to each other; A burner is connected to the premixing chamber to transport materials into the premixing chamber, the burner includes a first gas path and / or a second gas path connected to the premixing chamber, the first gas path is used to pass a first gasifying agent into the premixing chamber, the second gas path is used to pass a second gasifying agent into the premixing chamber, and the premixing chamber is used to mix the materials with the first gasifying agent and / or the second gasifying agent.

2. The biomass gasifier according to claim 1, characterized in that: The burner includes a material conveying pipe and a conveying shaft, wherein the material conveying pipe is communicated with the premixing chamber, and the conveying shaft sequentially penetrates the material conveying pipe and the premixing chamber, and the conveying shaft is provided with a first cavity and a first gasifying agent outlet communicated with the first cavity, and the first gasifying agent outlet is located in the premixing chamber, so that the conveying shaft forms the first gas path.

3. The biomass gasifier according to claim 2, characterized in that: There are a plurality of first gasifying agent outlets, which are distributed on the circumferential surface of the conveying shaft in a spiral manner at intervals along the axial direction of the conveying shaft.

4. The biomass gasifier according to claim 3, characterized in that: The conveying shaft can rotate around its own axis. The section of the conveying shaft located in the material conveying pipe is provided with spiral blades extending outward. The spiral blades and the spiral distribution of the first gasifying agent outlet on the conveying shaft have the same spiral direction.

5. The biomass gasifier according to claim 3, characterized in that: The section of the conveying shaft provided with the first gasifying agent outlet comprises a cylindrical section and a conical section, wherein the conical section is closer to the gasification chamber relative to the cylindrical section, and the diameter of the conical section gradually increases along the extending direction of the conveying shaft toward the gasification chamber.

6. The biomass gasifier according to claim 3, characterized in that: A disturbance strip is also arranged on the section of the conveying shaft where the first gasifying agent outlet is arranged.

7. The biomass gasifier according to any one of claims 2 to 6, characterized in that: The burner includes a second gasifier chamber, which is surrounded by the material conveying pipe and communicated with the premixing chamber. The second gasifier chamber is provided with a second gasifier inlet and guide vanes, and the airflow direction of the second gasifier flowing into the premixing chamber is adjusted by the guide vanes so that the second gasifier chamber forms the second gas path.

8. The biomass gasifier according to claim 7, characterized in that: The airflow rotation direction of the first air path is opposite to the airflow rotation direction of the second air path.

9. The biomass gasifier according to any one of claims 2 to 6, characterized in that: The inner wall of the premixing chamber includes an inclined wall, and along the direction in which the conveying shaft extends toward the gasification chamber, the distance between the inclined wall and the material conveying pipe gradually decreases, so that the annular gap between the inclined wall and the conveying shaft forms a material drop opening.

10. The biomass gasifier according to any one of claims 1 to 6, characterized in that: The burner also includes a third gas path, which includes a third gas path chamber connected to the premixing chamber. The third gas path chamber is provided with an airflow guiding mechanism, and the airflow guiding mechanism makes the airflow direction flowing into the premixing chamber the same as the airflow direction of the second gasifying agent flowing into the premixing chamber.

11. A biomass gasification system, characterized in that: It comprises the biomass gasifier as described in any one of claims 1-10.

12. The biomass gasification system according to claim 11, characterized in that: It also includes a screw conveying part, which includes a hopper unit, a feeding control unit and a screw conveying unit that are connected in sequence. The screw conveying unit is connected to the burner of the biomass gasifier. The feeding control unit is used to control the delivery amount of materials from the hopper unit into the screw conveying unit.

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