| The Jurassic coal resources was rich in Xinjiang, forecast resources ranked first in the country, of which low rank bituminous coal accounted for 80%, which was mainly used as coal, the use of extensive way. There was short of water in Xinjiang region, the development of high value-added, water conservation coal chemical industry was one of the effective ways to achieve sustainable and healthy development of coal resources in the area. The purpose of this paper is to provide a first-hand basic data for the efficient and cleaned utilization of Jurassic coal in Xinjiang.This paper systematically analyzed coal quality characteristics and rock properties of Xiaohonggou coal, we determined the way of processing and utilization of coal through basic coal quality analysis, and to do a comparative analysis for the manual separation of vitrain and fusain to clarify the nature of the characteristics and differences.Optimal separation density level of Xiaohonggou coal was determined by the heavy liquid separation, vitrinite of less than 1.31g/cm~3 and inertinite 1.31-1.47g/cm~3. In wettability of coal and rock components as the main difference between physical and chemical properties,flotation yield and enrichment of components was referenced to explore the effects of aeration rate, speed, pulp density, collector dosage, the amount of foaming agent five kinds of single factor to the overall efficiency of the flotation to determine coal and rock optimum flotation conditions component was aeration rate 0.25m~3/(m~2.min), speed 2000 rpm, pulp density 40g/L,collector dosage 1600g/t, foaming agent of 160g/t. In this case, the floating yield was 61.31%,the content of vitrinite in floats was 80.79%, the comprehensive efficiency of the flotation reached 30.34%.According to the characteristics of Xiaohonggou coal, it was believed that low temperature pyrolysis of improving the yield of tar as core was an effective way to increase the efficiency. Doing low temperature pyrolysis on the Xiaohonggou coal, which explored the effect of coal components, pretreatment and pyrolysis process three factors on the tar yield.The results showed that vitrinite content of pyrolysis raw materials affected significantly, the tar yield of vitrinite enrichment was 2.47% higher than coal; swelling of pretreatment influenced significantly increase of 4.6% than the untreated coal; a greater influenceof pyrolysis process was final pyrolysis temperature and catalyst, respectively compared with coal tar yield increase of 0.57% and 0.77%. The orthogonal experimental analysis of main factors affecting pyrolysis was found that the main factors affect the yield of tar in the order:swelling> final pyrolysis temperature> heating rate> catalysts> ultrasonic> holding time, the optimum conditions: NMP+EDA swelling 36 h, final pyrolysis temperature 570℃, rate of heating 12℃/min, quality of catalyst 1:20, ultrasonic treatment 15 min, holding time 18 min.Under these conditions, tar yield of coal sample was 16.76%, compared with raw coal,increased by 7.63%.The results of comparative analysis of the raw coal and semi coke showed that the main removal in low temperature pyrolysis were the aliphatic hydrogen and alkylated functional group in raw coal and vitrain, while carbon-oxygen bonds was decreased in fusain, the degree of aromatic after pyrolysis was increasing. Compared with raw coal and inertinite enrichment concentrate, vitrinite enrichment concentrate had a high activity in pyrolysis. Swelling can remove the functional groups that can also do in low temperature pyrolysis, it also can reduce the degree of aromatic of coal, increasing the coal overall activity and getting more liquid products. Chemical treatment was more better than physical treatment of the influenceon the tar yield. |
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