CN112251259A

CN112251259A - Cylindrical gasification furnace

Info

Publication number: CN112251259A
Application number: CN202011220621.2A
Authority: CN
Inventors: 张凝; 张国义; 贾天新
Original assignee: Beijing One A Hi Tech Energy Technology Co ltd
Current assignee: Beijing hengran Technology Co.,Ltd.
Priority date: 2020-11-05
Filing date: 2020-11-05
Publication date: 2021-01-22
Anticipated expiration: 2040-11-05
Also published as: CN112251259B

Abstract

The invention discloses a cylindrical gasification furnace, which comprises a gasification chamber, a cooling section and a feeding device. The gasification chamber is in a diameter-variable cylinder shape, the upper part of the gasification chamber is a vertical uniform cross section, the lower part of the gasification chamber is a variable cross section, and the gasification chamber is sequentially provided with a gradually expanding area, a uniform diameter area and a gradually reducing area from bottom to top. The bottom of the gasification chamber is provided with a primary air distribution device, a lower secondary air port, a middle secondary air port and an upper secondary air port are sequentially arranged in a gradually expanding area, an equal-diameter area and a gradually reducing area from bottom to top, secondary air outlet directions of the secondary air ports at the same height respectively form secondary air rotational flows surrounding the gasification chamber, and the directions of the vertically adjacent secondary air rotational flows are opposite. The invention has the advantages of high coincidence between the gasification process and the fluidization process, high calorific value of the gasified gas and the like.

Description

Cylindrical gasification furnace

Technical Field

The invention relates to a cylindrical gasification furnace, in particular to a gasification furnace capable of being used for gasifying solid wastes, and belongs to the field of solid fuel gasification.

Background

The combustible solid waste such as domestic garbage, biomass and the like often influences the combustion stability of the combustible solid waste in an incinerator due to higher water content, causes the problems of insufficient combustion or deflagration and the like, and the water is evaporated into the flue gas so that the water content of the flue gas is higher, and the corrosion of a pipeline and subsequent equipment is easily caused. The water in the domestic garbage and the biomass is fully utilized as a gasifying agent to participate in the reaction after being gasified and combusted, so that the reaction stability is improved, and the water content in the flue gas is reduced; and the gasification process has a homogenizing effect on the domestic garbage and biomass with complex components, so that the subsequent combustion process is more stable and sufficient.

The use of Turbulent Fluidized Bed (TFB) for its gasification process is clearly advantageous due to the complex and variable form of the combustible components. A turbulent fluidized bed belongs to a fluidized reactor, a common fluidized gasification device has contradiction between gasification oxygen demand and fluidized medium flow, and for combustible solid waste with low calorific value, the fluidized medium flow is usually obviously larger than the requirement of gasification oxygen demand, so that redundant oxygen enters a gasification zone, and the calorific value of gasified gas is reduced.

Disclosure of Invention

The invention aims to provide a cylindrical gasification furnace which can be used for waste gasification, improves a gas-solid two-phase mass transfer process by variable cross section arrangement and multistage configuration of gasification gas in a gasification chamber, realizes the conjunction of the gasification process and a fluidization process, reduces the flow of a fluidization medium and improves the heat value of the gasification gas.

The invention is realized by the following technical scheme:

a cylindrical gasification furnace comprises a gasification chamber, a cooling section and a feeding device.

The gasification chamber is in a diameter-variable cylinder shape, namely the cross section of the gasification chamber is circular. The upper part of the device is a vertical uniform cross section, the lower part of the device is a variable cross section, and the device is sequentially provided with a gradually expanding area, an equal diameter area and a gradually reducing area from bottom to top; said divergent zone height H₁With a base diameter of D₁Said constant diameter zone height H₂Having a diameter D₂(ii) a The height H of the tapering region_3，Its top diameter is D₃(ii) a Has H₁>H₃>H₂、D₁<D₃<D₂And D is₂/D₁≥5、D₂/D₃≥3、H₁/H₂≥4、H₁/H₃≥2。

The front part of the gasification chamber is provided with a feeding device, and the wall surface of the gradually expanding area of the gasification chamber is provided with a feeding hole communicated with the feeding device; and a primary air distribution device is arranged at the bottom of the gasification chamber and used for introducing primary air (gasification medium).

The gasification chamber is provided with a plurality of secondary tuyeres, including from down up set gradually the lower secondary tuyere, well secondary tuyere and the last secondary tuyere of divergent district, constant diameter district and convergent district, just lower secondary tuyere, well secondary tuyere and last secondary tuyere all set up a plurality of along same height.

And a flue gas channel is arranged between the cooling section and the top of the gasification chamber and is connected with the cooling section.

In the technical scheme, the inner wall surfaces of the lower part of the vertical uniform section and the variable section of the gasification chamber are both coated with refractory materials.

In the technical scheme, secondary air rotational flows surrounding the gasification chamber are respectively formed in the air outlet directions of the secondary air ports at the same height, and the directions of the vertically adjacent secondary air rotational flows are opposite.

The invention has the following advantages and beneficial effects: the variable cross section in the gasification chamber is arranged to reduce the amount of the bottom fluidization medium, and the gasification gas is configured in multiple stages to improve the mass transfer process of gas phase and solid phase, so that the gasification process is matched with the fluidization process, and the heat value of the gasification gas is improved.

Drawings

FIG. 1 is a schematic view of a cylindrical gasification furnace according to the present invention.

In the figure: 1-a gasification chamber; 11-vertical uniform cross-section; 12-variable section; 13-primary air distribution device; 14-a feed inlet; 15-lower secondary tuyere; 16-middle secondary air port; 17-secondary air inlet; 2-a cooling section; 3-a feeding device.

Detailed Description

The following describes the embodiments and operation of the present invention with reference to the accompanying drawings.

The terms of orientation such as up, down, left, right, front, and rear in the present specification are established based on the positional relationship shown in the drawings. The corresponding positional relationship may also vary depending on the drawings, and therefore, should not be construed as limiting the scope of protection.

As shown in fig. 1, a cylindrical gasification furnace is a cylindrical gasification furnace including a gasification chamber 1, a cooling section 2, and a feeding device 3.

The gasification chamber 1 is in a diameter-variable cylinder shape, namely the cross section of the gasification chamber is circular, which is beneficial to thermal expansion and sealing.

The upper part is a vertical uniform section 11, the lower part is a variable section 12, and the upper part is from bottom to topA gradually expanding area, an equal diameter area and a gradually reducing area are sequentially arranged; divergent zone height H₁With a base diameter of D₁Height H of equal diameter zone₂Having a diameter D₂(ii) a Height H of the tapering region_3，Its top diameter is D₃. Based on the comprehensive consideration of gas-solid two-phase flow, space out-phase reaction, heat transfer and other angles in the gasification furnace, the optimal temperature distribution and quality (concentration) distribution in the gasification furnace are obtained, the best gasification effect is obtained, and each region in the gasification chamber is according to H₁>H₃>H₂、D₁<D₃<D₂And D is₂/D₁≥5、D₂/D₃≥3、H₁/H₂≥4、H₁/H₃The setting is more than or equal to 2.

The inner wall surfaces of the lower part of the vertical uniform section 11 and the variable section 12 of the gasification chamber 1 are both coated with refractory materials, so that heat storage gasification is formed in the gasification chamber 1, and the gasification chamber is particularly suitable for solid wastes with low calorific values.

The front part of the gasification chamber 1 is provided with a feeding device 3, and the wall surface of the gradually expanding area of the gasification chamber 1 is provided with a feeding hole 14 communicated with the feeding device 3; the bottom of the gasification chamber 1 is provided with a primary air distribution device 13 for introducing primary air. A plurality of wind caps are arranged on the primary wind distribution device 13. In one embodiment, the blast caps are directional blast caps which are arranged according to circumferential tangent lines, so that the bottom of the gasification chamber forms vortex flow. In another embodiment, symmetrical hoods are adopted as the hoods to form a uniform fluidization structure.

The gasification chamber 1 is provided with a plurality of secondary tuyeres, including a lower secondary tuyere 15, a middle secondary tuyere 16 and an upper secondary tuyere 17 which are arranged in a gradually expanding area, an equal diameter area and a gradually reducing area in sequence from bottom to top, and the lower secondary tuyere 15, the middle secondary tuyere 16 and the upper secondary tuyere 17 are all provided with a plurality of secondary tuyeres along the same height. The air outlet directions of the secondary air ports at the same height form secondary air rotational flows surrounding the gasification chamber 1 respectively, and the rotational flows of the vertically adjacent secondary air ports are opposite in direction, so that mass transfer homogenization is realized in the minimum space to the maximum extent.

The rotational flow structure at the bottom enables the raw material entering the gasification chamber to realize sufficient gas-solid mixing at the minimum fluidization speed, thereby reducing the flow of the fluidization medium. The secondary air at the middle upper part is all distributed in a reverse rotation way, so that the uniform gas-solid mixing and mass transfer between gas phases can be realized to the maximum extent, the rapid consumption of oxygen in the gas is realized, and the gasification efficiency is improved. In addition, all the media are distributed in the rotating directions, and the rotating directions are opposite, so that efficient transverse disturbance and mixing can be formed with the gas-solid two-phase flow vertically upwards, particularly the stress distribution of upward movement of particles is changed, and the upward conveying amount of the particles is reduced, so that the gasification efficiency of the middle and lower parts is improved, the ash flying amount is reduced, the ash content of gasified gas is reduced, and the post-treatment cost is reduced.

The cooling section 2 is connected with the top of the gasification chamber 1 through a flue gas channel, and the gasified gas from the gasification chamber 1 is cooled. The cooling section 2 adopts a tube type heat exchanger structure.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A cylindrical gasification furnace is characterized in that: the gasification furnace comprises a gasification chamber (1), a cooling section (2) and a feeding device (3);

the gasification chamber (1) is cylindrical, the upper part of the gasification chamber is an upright uniform cross section (11), the lower part of the gasification chamber is a variable cross section (12), and the gasification chamber is sequentially provided with a gradually expanding area, an equal diameter area and a gradually reducing area from bottom to top; said divergent zone height H₁With a base diameter of D₁Said constant diameter zone height H₂Having a diameter D₂(ii) a The height H of the tapering region_3，Its top diameter is D₃(ii) a Has H₁>H₃>H₂、D₁<D₃<D₂And D is₂/D₁≥5、D₂/D₃≥3、H₁/H₂≥4、H₁/H₃≥2；

The front part of the gasification chamber (1) is provided with a feeding device (3), and the wall surface of the gradually expanding area of the gasification chamber (1) is provided with a feeding hole (14) communicated with the feeding device (3); a primary air distribution device (13) is arranged at the bottom of the gasification chamber (1) and used for introducing primary air;

the gasification chamber (1) is provided with a plurality of secondary tuyeres, and the secondary tuyeres comprise a lower secondary tuyere (15), a middle secondary tuyere (16) and an upper secondary tuyere (17) which are sequentially arranged in the gradually expanding area, the equal diameter area and the gradually reducing area from bottom to top, and the lower secondary tuyere (15), the middle secondary tuyere (16) and the upper secondary tuyere (17) are all arranged at a plurality of positions along the same height;

and a flue gas channel is arranged between the cooling section (2) and the top of the gasification chamber (1) to be connected.

2. The cylindrical gasification furnace according to claim 1, wherein: and refractory materials are laid on the lower part of the vertical uniform section (11) and the inner wall surfaces of the variable section (12) of the gasification chamber (1).

3. The cylindrical gasification furnace according to claim 1, wherein: secondary air rotational flows surrounding the gasification chamber (1) are respectively formed in the air outlet directions of the secondary air ports at the same height, and the directions of the vertically adjacent secondary air rotational flows are opposite.