Department of Mechanical and Electrical Engineering,Yongcheng Vocational College
College of Chemistry and Chemical Engineering,Henan Polytechnic University

高梯度磁选磨煤机回粉技术在煤粉喷吹燃烧系统中的嵌入式结合,可有效降低燃煤中黄铁矿含量、减轻SO2环境污染,其中粗煤分离器对煤系黄铁矿的预先去除效率是影响磁分选回粉质量的重要环节。选取煤系黄铁矿单体与煤基质单体的混合样作为模拟样,基于自制柱式流化床,模拟了不同粒度、流化速度以及混合比影响下颗粒的运动特性。结果表明:流化床分选区的流化速度较均匀,分选区存在一次错配区和二次错配区;实际分选过程各粒级颗粒运动特性截然不同,粒级增大对应流化速度的响应降低,粗粉颗粒煤基质模拟产率为99.4%,细粉颗粒模拟产率为91.7%,细粉颗粒在不同条件下均为难处理对象,要避免前端的过磨现象;粗粉颗粒中煤基质在重产物中的损失及细粉颗粒中煤系黄铁矿在轻产物中的夹带是造成流化床分选效率低的主要原因;同时,随煤系黄铁矿占比增大,粗粉颗粒运动特性变化不明显,中粒级中的混合物料在分选区中的二次错配区出现返料现象;开展了基于模拟参数的对比分选试验,试验收集轻产物硫分降幅明显且试验产率与模拟产率接近。研究结果对于提高喷吹效率、降低燃煤污染具有积极意义。

The pyritecontent in the returned powder of coal millcan be effectively reduced and the SO2 environmental pollution can be reduced due to high-gradient magnetic separation technology, as the embedded combination in the coal injection combustion system. Also,the pre-removal efficiency of coarse coal powder classifier is an important factor affecting the quality of magnetic separation and powder recovery. Coal-pyrite and coal-matrix were selected as mixed simulation samples. Based on a self-made column fluidized bed, the particles motion characteristics were simulated under the influence of particle size, fluidization speed and mixing ratio. The results show thatthe fluidization velocity is relatively uniform in column fluidized bed, and there are primary and secondary mismatching zones in the separation zone. In the actual separation process, the particles motion characteristics of each particle size are completely different. The increaseof the particle size corresponds to a decrease response of the fluidization velocity. The simulation yield of coarse coal-matrix is 99.4%, andthe yield of fine coal-matrix is 91.7%. The fine particles are obviously difficult to handle under different conditions, so the over-grindingphenomenon in the front section should be avoided. The loss of the coarsecoal - matrix in the heavy products and the entrainment offine middling coal pyrite in the light products are the main reasons for the low separation efficiency of fluidized bed. Also, with the increase of the proportion of coal-pyrite, the movement characteristics of coarse particles do not change significantly, and the mixed materials in the medium particle size show a phenomenon of material return in the secondary mismatch zone of the sorting area. The comparisonseparation experiment under the simulation parameters was further carried out. The sulfur content of the enriched light products is greatlyreduced at the optimal simulation parameters, and the experimental yield is close to the simulated yield. The research results are of positive significance for improving the coal injection combustion efficiency and finally reducing coal pollution.

河南省高等学校重点科研资助项目(21A440012);河南省高校基本科研业务费专项资金资助项目(NSFRF200311)

于艳辉,史长亮.柱式流化床去除喷吹煤中煤系黄铁矿过程模拟[J].洁净煤技术,2023,29(12):119-127.

YU Yanhui,SHI Changliang.Removal process simulation on coal-pyrite of injection coal based on column fluidized bed[J].Clean Coal Technology,2023,29(12):119-127.