Coal blending and coking method for producing coke at high pulverized coal proportion

Abstract

The invention discloses a coal blending and coking method for producing coke at a high pulverized coal proportion. The pulverized coal proportion is 33-40 percent. The coal blending and coking method comprises the following steps: (1) determining single coal as gas coal, 1 / 3 coking coal, fat coal, coking coal and lean coal, and determining the proportions of the single coal; (2) mixing the single coal, smashing the mixed single coal, measuring weight percentage of coal of which the particle size is less than 0.3mm in blended coal within a fineness range of 80+ / -2 percent, and determining a fat coal proportion in which a maximum thickness y value of a gelatinous layer is greater than 25mm, the maximum Aoya expansion degree b value is greater than 220 percent and the Gieseler fluidity solid-soft temperature interval is greater than 110 DEG C in the prepared fat coal according to different weight percentages. According to the coal blending and coking method, the using amount of the fat coal which has high expansion performance and stable plastic mass is increased, so that the defect of low contact fusion compact degree between pulverized coal and other coal particles due to lowering of the specific gravity of a coal pile when the pulverized coal proportion in the blended coal is over high can be overcome, and superior coke having high quality and stable thermal strength is produced, and the demands of blast furnaces of over 3,000m<3> are met.

Description

technical field [0001] The invention belongs to the technical field of metallurgy and coking, and in particular relates to a coal blending and coking method for producing coke under a high pulverized coal ratio. Background technique [0002] The particle size composition of blended coal is one of the factors affecting the thermal strength of coke. Traditional top-loading coke ovens generally control the fineness of blended coal. Domestic coking plants generally control the proportion of coal with particle size less than 3mm in the furnace at about 80±2%. [0003] Problems in the prior art: Due to the difference in particle size distribution of raw coal and the difference in Hastelloy's grindability index, when the fineness is 80 ± 2%, the weight percentage of the particle size smaller than 0.3mm in the blended coal is 33% to 40% %, and the pulverized coal with a particle size of less than 0.3mm deteriorates in coking property, causing the fluctuation of coke thermal strength...

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Problems solved by technology

[0003] Problems in the prior art: Due to the difference in particle size distribution of raw coal and the difference in Hastelloy's grindability index, when the fineness is 80 ± 2%, the weight percentage of the particle size smaller than 0.3mm in the blended coal is 33% to 40% %, and the coking property of pulverized coal smaller than 0.3mm is degraded, causing the fluctuation of coke thermal strength to reach more than 5 percentage points, which is likely to cause fluctuations in blast furnace conditions

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