Low-temperature dry distillation process of low-rank pulverized coal

Abstract

The invention discloses a low-temperature carbonization process for low-order pulverized coal. A drying and dewatering system, a fine pulverized coal recycling system, a condensate water recycling system, a coal low-temperature carbonization system and an energy supply system are involved; moisture-containing exhaust and dry coal are discharged after raw coal is dried and dewatered through the drying and dewatering system; fine pulverized coal is separated from the moisture-containing exhaust through the fine pulverized coal recycling system; the fine pulverized coal is mixed with the dry coal to obtain a mixture through a pipeline, and the mixture enters the coal low-temperature carbonization system to produce semi-coke, coal tar and pyrolysis coal gas. The coal gas produced by the low-temperature carbonization process for the low-order pulverized coal is high in purity, so that external supply coal gas is high in quality and high in calorific value; the yield of the tar is higher; the effective utilization rate of energy sources is improved. The raw coal is subjected to the carbonization after being dried and dewatered in devices of the process, so that the moisture content in the coal gas is low, and little wastewater is generated in the processes of purifying and separating; environment protection treatment is simple and feasible. A closed circulating mode is adopted for coke quenching and drying; afterheat in a process flow is fully recycled.

Description

technical field [0001] The invention relates to the technical field of low-temperature dry distillation of coal, in particular to a low-temperature dry distillation process of low-rank pulverized coal. Background technique [0002] Coal medium and low temperature pyrolysis technology has been developed for more than 200 years, and more than 80 production methods have been formed, and there are a certain number of relatively mature technologies. [0003] Lignite-like low-rank coals are suitable for low-temperature carbonization processing. Through low-temperature carbonization processing, lignite can be converted into gas, liquid, and solid products, which has good economic and social benefits. [0004] Low-temperature dry distillation technology is a technology that has been generally recognized and valued at present. It refers to the process of heating coal to 500-700°C in the absence of air or with a small amount of air, and thermally decomposing it to produce gas, tar and...

AI Technical Summary

Problems solved by technology

[0016] The disadvantages of the Garrett process mainly include: the generated tar and dust semi-coke will adhere to the inner wall of the cyclone and the pipeline, and the long-term operation will block the pipeline; the contact between the circulating semi-coke and the input coal, and sufficient heat exchange It will intensify the fine pulverization of coal, increase the amount of semi-coke in circulation, and make the coal processing capacity of the system unable to increase too much

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