Method for preparing coal water slurry by mixing coal and semicoke as raw materials with wastewater

Abstract

The invention discloses a method for preparing coal water slurry by mixing coal and semicoke as raw materials with wastewater, the method comprises the following steps: crushing the coal and the semicoke as the raw materials; mixing the crushed raw materials with the wastewater generated in the coal gas purification process, and then mixing with water, an additive, limestone and ammonia water through a coal mill to carry out high-concentration grinding to prepare coal water primary slurry with certain solid particle size distribution; and filtering the primary coal water slurry to obtain the coal water slurry. According to the method disclosed by the invention, the coal water slurry technology is adopted, the problem in the coal pyrolysis quality separation grading utilization process canbe solved, namely, the difficult-to-treat wastewater generated by the coal gas purification process and the 6-mm-below difficult-to-utilize coal and semicoke are sued as the raw materials, and the prepared coal water slurry is suitable for gasification, so that the utilization rate of the raw materials is improved, the environment is protected, the cost is saved, and the problems in the prior artare effectively solved.

Description

technical field [0001] The invention belongs to the technical field of clean coal and relates to a method for preparing coal-water slurry by mixing a small amount of waste water with coal and semi-coke as raw materials. Background technique [0002] The energy structure characteristics of my country's lack of oil, low gas, and rich coal predetermine that my country's energy consumption will be dominated by coal for a long time. Compared with the current extensive and single coal utilization method, the coal pyrolysis classification utilization technology improves the comprehensive energy efficiency of coal utilization. The low-temperature carbonization technology of externally heated rotary furnace coal is an advanced technology in the category of coal pyrolysis, quality separation and classification utilization technology. External heating rotary furnace coal low temperature carbonization technology adopts pulverized coal with a particle size of 6-30 mm, which is difficult...

AI Technical Summary

Problems solved by technology

However, in this production process, there are still coal powders below 6 mm that cannot be used, and a small amount of coke powder below 6 mm in the produced semi-coke is difficult to effectively use

The current method is to concentrate the pulverized coal and coke powder below 6mm and send them to the boiler for combustion, which has low economic benefits.

At the same time, due to the use of dry coke quenching, the waste water generated by gas purification is not used for coke quenching. Although the gas phase pollution caused by wet coke quenching is avoided, zero discharge of waste water cannot be achieved, and the coal gas in the process of pyrolysis, classification and utilization The wastewater produced by the purification process is difficult to purify and treat due to its complex composition. Not only does the treatment cost high, but it often causes environmental pollution

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