| Currently, the efficient and clean use of coal is one of the effective ways to solve environmental issues and energy issues, CWS technology is an effective way of clean utilization of coal. Semi-coke is a product of low rank bituminous or lignite at low temperature carbonization, in addition, Shenfu coal powder and semi-coke are affected by narrow use, low utilization, production overcapacity and other problems.In this paper, improve resource utilization and energy saving as the main purpose, semi-coke and Shenfu pulverized coal as raw material for coal water slurry preparation. Three different size samples were prepared by Superfine impact mill, different size samples were grade pulp and CWS characteristics were detected. The influence of the particle size distribution on slurry properties and applicability of Alfred particle size distribution model in this experiment were studyed. Select different types of dispersant for pulping experiments, the performance of the pulp, effects of different types and adding amount of dispersants on CWS properties were studyed..Research of gradation showed that concentration of CWS by unimodal gradation was 52% or less, it is difficult to meet the requirements of industrial applications, bimodal gradation obviously improved the effect of pulp, but the highest concentration of CWS not exceeding 61%. The particle size distribution and Alfred model were compared and analyzed, although triplet grading slightly deviation from the ideal model of particle size distribution, but the best pulping obtained under the triplet level ratio of 3: 1: 1, the highest concentration up to 62%. The result show that doublet and triplet grading particle size distribution is more reasonable to optimize the pulping results.By study the adsorption of dispersant on the particle surface, it obtain a majority of the dispersant to reach the adsorption equilibrium in an amount of 0.4wt%, SL and SH adsorption on pulp particles larger than 1.0 wt %. This has important implications for the rational use of dispersants, saving cost and other aspects of dispersant. When using different dispersants pulp, the lowest apparent viscosity and good stability were obtained when Shenfu semi-coke and pulverized coal mass ratio of 3: 1.Investigate the pulp effect of different types of dispersants from the apparent viscosity, stability and liquidity, etc. The results show that the maximum concentration of CWS pulped with industry complex dispersant TY-1J is 66%, the stability is 15 d, good fluidity; SH pulp and stability are the worst, with an average of about 10 d. Lignin-based dispersants and humic acid-based dispersants compound prepare CWS, it gives primary factors affecting preparation of complex pulp are gradation, types of dispersants, ratio of dispersants, dispersant dosage, optimal combination of pulp as follows: graded as 3: 1: 1, M2 and SH compounded as 1: 1, the amount of dispersant is 0.8wt%, comparative analysis the compound dispersant and alone dispersant pulp, pulp apparent viscosity, stability and liquidity are all improved. When the apparent viscosity value is 1137 mpa·s, pulp concentration value is 64%, sulfur content value is 0.29%, ash value is 9.41%, calorific value is 24.65 MJ/Kg, which are in line with national CWS standards and meet the industrial application of gasified CWS. |
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