Biomass gasifier with central suction

Abstract

The utility model provides a kind of middle suction type biomass gasification furnace, including ash tray, the lower section furnace body is arranged on ash tray upper portion, the upper section furnace body is arranged on lower section furnace body upper portion, two layers of jacketed cylinders are arranged in the outer portion of the upper section furnace body, respectively are reduction gas jacket, pyrolysis gas jacket, reduction gas jacket is inside, pyrolysis gas jacket is outside, the reduction gas jacket is communicated with lower section furnace body, reduction gas jacket upper portion is provided with middle suction upper outlet, the pyrolysis gas jacket is communicated with upper section furnace body, and pyrolysis gas jacket lower portion is provided with middle suction lower outlet. This gasification furnace has the advantages of high gasification efficiency, pipeline is not easy to block and the like.

Description

Technical Field

[0001] This utility model mainly relates to the technical field of biomass gasification furnaces, specifically a medium-suction biomass gasification furnace. Background Technology

[0002] Biomass gasification furnaces convert macromolecules of biomass, such as cellulose, hemicellulose, and lignin, into smaller molecules of biomass combustible gas, biochar, and liquid. The main combustible components of biomass combustible gas are CO, H2, and CH4, with trace amounts of CnHm (n>1). It can be widely used in various fields of industrial and agricultural production, such as power generation, gas supply, and heating (replacing coal combustion).

[0003] In existing technologies, biomass gasifiers mostly adopt upward or downward suction structures. Simple upward suction gasifiers have low outlet temperatures, which leads to excessive condensate and tar, causing pipe blockages. When biomass gas enters the kiln, the high moisture content in the biomass gas also results in heat loss. Simple downward suction gasifiers have high outlet biomass gas temperatures, but the gas carried out has significant heat loss because the final layer of the downward suction gasifier is a reduction layer, which cannot completely burn the carbon. Therefore, the ash residue has a high carbon content, resulting in low gasification efficiency. Furthermore, because the gas flow and raw materials both descend, the gas leaves through the fine particle bed after gasification, resulting in a high ash content. Utility Model Content

[0004] To address the shortcomings of current technology, this utility model combines existing technology and, based on practical applications, provides a medium-suction biomass gasification furnace, which has advantages such as high gasification efficiency and less clogging of pipelines.

[0005] The technical solution of this utility model is as follows: A mid-suction biomass gasifier includes an ash pan, a lower furnace body on the upper part of the ash pan, and an upper furnace body on the upper part of the lower furnace body. The upper furnace body is externally fitted with two jacketed cylinders, namely a reducing gas jacket and a pyrolysis gas jacket, with the reducing gas jacket inside and the pyrolysis gas jacket outside. The reducing gas jacket is connected to the lower furnace body, and the upper part of the reducing gas jacket is provided with a mid-suction upper outlet. The pyrolysis gas jacket is connected to the upper furnace body, and the lower part of the pyrolysis gas jacket is provided with a mid-suction lower outlet.

[0006] Furthermore, a water jacket is installed on the outside of the lower section of the furnace body, and a primary air channel is provided at the bottom of the lower section of the furnace body.

[0007] Furthermore, the bottom of the reducing gas jacket is connected to the lower furnace body through a porous channel, and the reducing biomass gas from the lower furnace body is discharged from the upper outlet of the middle suction through the porous channel.

[0008] Furthermore, the upper inner side of the pyrolysis gas jacket is connected to the upper section of the furnace body, and the pyrolysis biomass gas returns from top to bottom through the pyrolysis gas jacket and is discharged through the middle suction lower outlet.

[0009] Furthermore, a feeding valve and a hopper are provided on the upper part of the upper section of the furnace body.

[0010] The beneficial effects of this utility model are: In this gasifier structure, the reduced biomass gas is discharged from the upper outlet of the middle suction, and the pyrolysis biomass gas is discharged from the lower outlet of the middle suction. The pyrolysis biomass gas is heated by the thermal radiation of the reduced biomass gas at 350-450℃, which completely evaporates the condensate in the pyrolysis biomass gas and completely vaporizes the small amount of tar. This prevents pipe blockage and provides convenient conditions for subsequent processing. At the same time, the temperature of the reduced biomass gas is reduced, which reduces the investment required for subsequent cooling equipment. Attached Figure Description

[0011] Appendix Figure 1 This is a schematic diagram of the overall structure of a biomass gasification furnace.

[0012] The labels shown in the attached diagram are: 1. Ash pan; 2. Lower furnace body; 3. Pyrolysis gas jacket; 4. Reducing gas jacket; 5. Upper furnace body; 6. Upper outlet of the middle suction; 7. Feeding valve; 8. Hopper; 9. Lower outlet of the middle suction; 10. Porous channel. Detailed Implementation

[0013] The present invention will be further described in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent forms also fall within the scope defined in this application.

[0014] refer to Figure 1 The diagram shown is a schematic diagram of the structure of a mid-suction biomass gasifier proposed in this embodiment.

[0015] The gasifier mainly consists of a hopper 8, a feeding valve 7, an upper furnace body 5, a lower furnace body 2, and an ash pan 1, arranged sequentially from top to bottom.

[0016] The lower furnace body 2 is a cylindrical steel plate structure covered with a water jacket. It provides a high-temperature, oxygen-deficient environment for the biomass feedstock. A primary air channel is located at the bottom of the furnace body to provide the gasifying agent—oxygen / air and steam—for the biomass feedstock gasification process. Within the lower furnace body 2, the biomass feedstock undergoes oxidation and reduction stages sequentially.

[0017] The upper furnace body 5 is made of rolled steel plate and covered with a two-layer jacketed cylindrical structure. These are the reducing gas jacket 4 in the middle and the pyrolysis gas jacket 3 on the outermost side. The reducing gas jacket 4 has a middle suction upper outlet 6 at the top and is connected to the lower furnace body 2 through a porous channel 10 at the bottom. The pyrolysis gas jacket 3 is connected to the upper furnace body 5 on the inner side of the top and has a middle suction lower outlet 9 at the bottom.

[0018] The upper furnace body 5 provides a low-temperature pyrolysis and drying environment for the biomass feedstock. The reduced biomass gas generated during the reduction process in the lower furnace body 2, reaching temperatures as high as 350-450℃, is discharged from the central suction outlet 6 through the porous channel 10. Within the upper furnace body 5, the biomass feedstock undergoes pyrolysis and drying stages sequentially. The pyrolysis biomass gas returns from top to bottom through the pyrolysis gas jacket 3 and is discharged from the central suction outlet 9. During this return process, the 120-150℃ pyrolysis biomass gas is heated to over 200℃ by the thermal radiation from the 350-450℃ reduced biomass gas. At this point, the condensate in the pyrolysis biomass gas has completely evaporated, and any remaining tar has been completely vaporized, preventing pipe blockage and facilitating subsequent processing. The reduced biomass gas, due to radiation, also cools to below 300-400℃, reducing investment in subsequent cooling equipment.

Claims

1. A biomass gasifier of downdraft type comprising an ash pan, a lower furnace body disposed on the upper portion of the ash pan, and an upper furnace body disposed on the upper portion of the lower furnace body, characterized in that, The upper section of the furnace body is equipped with two jacketed cylinders, namely a reducing gas jacket and a pyrolysis gas jacket. The reducing gas jacket is inside and the pyrolysis gas jacket is outside. The reducing gas jacket is connected to the lower section of the furnace body. The upper part of the reducing gas jacket is provided with a mid-suction upper outlet. The pyrolysis gas jacket is connected to the upper section of the furnace body. The lower part of the pyrolysis gas jacket is provided with a mid-suction lower outlet.

2. The downdraft biomass gasifier according to claim 1, wherein, The lower section of the furnace body is equipped with a water jacket, and a primary air channel is provided at the bottom of the lower section of the furnace body.

3. The downdraft biomass gasifier according to claim 1, wherein, The bottom of the reducing gas jacket is connected to the lower section of the furnace body through a porous channel, and the reducing biomass gas from the lower section of the furnace body is discharged from the upper outlet through the porous channel.

4. The downdraft biomass gasifier according to claim 1, wherein, The upper inner side of the pyrolysis gas jacket is connected to the upper section of the furnace body. The pyrolysis biomass gas returns from top to bottom through the pyrolysis gas jacket and is discharged through the middle suction lower outlet.

5. The downdraft biomass gasifier according to claim 1, wherein, The upper section of the furnace body is equipped with a feeding valve and a hopper.

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