Full water-cooled two-stage fixed bed liquid slagging gasification furnace

Abstract

The invention relates to a full water-cooled two-stage fixed bed liquid slagging gasification furnace which comprises a gasification furnace body, wherein the gasification furnace body comprises a furnace shell and a membrane type water cooling wall arranged inside the furnace shell; a central cylinder is arranged inside the gasification furnace body; a top end of the central cylinder is fixedly connected with the membrane type water cooling wall in a sealing manner; a feeding port communicated with the central cylinder is formed in the top of the gasification furnace body; a first gas outletand a second gas outlet are formed in an upper part of the gasification furnace body; the first gas outlet is communicated with the interior of the central cylinder; the second gas outlet is communicated with an inner space of the gasification furnace body located outside the central cylinder; a circle of spray nozzles are formed in a lower part of the gasification furnace body; a slagging port isformed in a center of the bottom of the membrane type water cooling wall; the bottom of the furnace shell is fixedly connected with a quench chamber by a flange; the top of the flange is fixedly connected with the slagging port by a support plate; a fire insulating hood having a downward opening is arranged in the quench chamber; the slagging port extends into the fire insulating hood; an annularburner nozzle is formed in the bottom of the slagging port; and the annular burner nozzle is arranged in the fire-insulating hood.

Description

Technical field [0001] The invention relates to a fully water-cooled two-stage fixed-bed liquid slag discharge gasifier, which belongs to the field of coal gasification devices. Background technique [0002] A typical pressurized fixed-bed liquid slagging gasifier is working. Usually, lump coal is added from the top of the gasifier, and the mixed superheated steam and oxygen are used as gasification agents to be sprayed into the bottom of the gasifier for gasification. reaction. In the gasification furnace, the coal and the high-temperature gas generated by the gasification agent are in reverse contact, and are dried, retorted, gasified, and finally oxidized and burned from top to bottom. The mixture of gasification product gas, tar and steam is discharged from the top of the gasifier. At the same time, because the combustion layer provides a high temperature above 2000 ℃, the ash at the bottom of the gasifier is discharged into the slag pool in liquid form, and then discharged...

AI Technical Summary

Problems solved by technology

The cooling water pipe is pre-buried inside the copper water-cooling component, which is complicated to process and high in cost

In addition, in order to ensure the safety of copper castings, forced water cooling is adopted, and the temperature difference between the inlet and outlet of cooling water should not be too large, resulting in a large amount of cooling water circulation in the water wall in the slag area, and the heat taken away by the cooling water cannot be directly used , reducing the utilization efficiency of the entire gasifier for heat

In addition, in order to ensure that the temperature of the shell of the gasifier is within a safe range, a layer of water jacket is installed in the shell of the traditional fixed-bed slag gasifier, but the water jacket has poor pressure bearing capacity. During the gasification process, Due to the pressure fluctuation of the gasifier, it is easy to cause the water jacket to be squeezed or broken, which brings safety hazards to the operation of the gasifier

Furthermore, the fire shield of the traditional fixed-bed liquid slagging gasifier is a layer of stainless steel plate, which requires long-term exposure to high-temperature flue gas during operation, which is prone to burning problems

[0004] In actual production, in addition to producing gas, the by-products of the fixed bed slag gasifier include tar. The fixed bed slag gasifier uses lump coal as feed material. Due to the entrainment of coal powder or the particle size of the lump coal is not up to the standard, the produced Dust will be entrained with the air flow to form tar residue, and because the tar and phenol content in the product gas of the gasification section is low, all of them will be passed into the dry distillation section to dilute the furnace top gas, and the tar content in the gas will be reduced, making the tar content It is difficult to extract

At the same time, in a typical fixed-bed slag gasifier, the high-temperature product gas in the gasification section directly rises to the carbonization section to provide heat for the carbonization reaction, and produces medium-temperature tar, and its yield and quality are lower than those of low-temperature carbonization.

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