A vertical multi-tube segmented gas-conducting type external heating pulverized coal carbonization method and device

Abstract

The invention relates to a vertical multi-pipe segmented gas guide type external heating pulverized coal destructive distillation method and device. A tubular destructive distillation process is utilized, a tower-shaped segmented vertical tubular structure is adopted to treat raw coal, the process sequentially comprises a first-stage drying process, a second-stage destructive distillation processand a first-stage cooling process from top to bottom, the positions of multiple rows of vertical pipes for conveying pulverized coal among all the sections are in one-to-one correspondence, and all the sections are independently arranged and organically coupled into a whole. Pulverized coal enters the pipes from the top of the device and indirectly exchanges heat with high-temperature flue gas outside the pipe and circulating water in the downward moving process, a heating medium of the drying section is hot flue gas obtained after the high-temperature flue gas is subjected to temperature adjustment, a heating medium of the destructive distillation section is hot flue gas generated by combustion of coal gas generated by the device, and a cooling medium of the cooling section is circulatingwater. In the rising process of the flue gas, heat exchange with descending pulverized coal is carried out, the temperature of the flue gas is continuously reduced, the temperature of the coal is continuously increased, and destructive distillation reaction is triggered. The device can improve the quality of semicoke, is high in heat exchange efficiency, improves the resource utilization rate andproductivity, reduces the production cost and reduces pollution.

Description

technical field [0001] The invention belongs to the technical field of coal chemical industry, and in particular relates to an external heating type pulverized coal dry distillation method and device. Background technique [0002] my country is rich in low-rank coal resources, and more than 50% of the proven coal reserves are low-rank coal. As a fossil energy resource, its clean, efficient, and comprehensive transformation and utilization are the future development direction. Polygeneration or cascaded utilization based on coal dry distillation conforms to the principles of clean, efficient, and comprehensive transformation and utilization, and has attracted the attention of researchers and developers. Coal dry distillation, as its main process unit, has received more attention. [0003] At present, the carbonization furnaces used for coal carbonization are mainly divided into two types: internal heating type and external heating type, and both the internal heating type and ...

AI Technical Summary

Problems solved by technology

At present, the main defects of the internal heating type are poor gas quality, heavy load on the follow-up purification system, large amount of sewage treatment, and inability to treat pulverized coal, etc.

The internal heat type dry distillation method is to directly pass the high-temperature flue gas produced by burning raw coal gas into the furnace, and directly contact with the raw coal for dry distillation. The dry distillation gas in the furnace is discharged from the top of the furnace together with the flue gas, which is called raw coal gas. Contains a large amount of inert gas-nitrogen, so the calorific value of the gas produced by this technology is low, which is not conducive to the utilization of gas in the subsequent industrial chain, and the resource utilization rate is low

In addition, the internal heating vertical furnace cannot process pulverized coal below 8mm, resulting in a great waste of resources and dust pollution

[0004] At present, the main problems of the existing external heating pulverized coal carbonization technology are small output, unstable operation, poor air permeability, and large investment.

However, this method also has its drawbacks. First, this method cannot separate the dry water from the dry distillation water in the raw coal carbonization process, and the amount of sewage in the subsequent purification system is relatively large; secondly, because the carbonization chamber of this process adopts a rectangular structure, the heating surface is two side, the heating area is small, the heating is uneven, and the heat transfer rate is low, thereby reducing the capacity of the device

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