红庆梁选煤厂降低块煤入选下限的研究

通过对红庆梁邻近矿井煤质资料的分析，说明红庆梁原煤具有低灰、低硫、低磷、中高发热量的特点。根据红庆梁选煤厂原煤特性及产品方案，提出采用弛张筛对原煤进行深度筛分，有效利用重介浅槽，降低块煤洗选下限的优化思路，最终确定红庆梁选煤厂工艺流程为：原煤经弛张筛进行6mm分级，150～6mm入块煤重介浅槽系统洗选，出精煤和矸石产品，-6mm末煤直接作为末煤产品销售。最后对选用工艺的技术可行性进行分析。原煤经重介浅槽分选后＋13mm灰分由13．54％降为6．38％，6～10mm灰分由12．86％降为6．43％，说明重介浅槽分选机对13～6mm末煤具有良好分选效果。弛张筛在谢桥选煤厂和张集北选煤厂使用效果很好．分级效率达80％以上．设备安全可靠。

Lower size of lump coal reduction measures in Hongqingliang coal preparation plant

The analysis of coal properties of mines near Hongqingliang coal mine shows that, the raw coal of Hongqingliang is low ash, low sulfur,low phosphorus and medium-high calorific value. Based on the coal properties and products structure, adopt flip-flop screen to separate raw coal, use dense-medium shallow-slot separator to reduce lower size of lump coal. Determine the technological process of Hongqingliang coal preparation plant. Set the classification size of flip-flop screen is 6 mm. The raw coal ranging from 150 mm to 6 mm is separated by dense- medium shallow-slot separator, the products are clean coal and gangue. The slack coal below 6 mm is sold directly. Through separation,the ash of raw coal above 13 mm decrease from 13.54 percent to 6. 38 percent,which decrease from 12. 86 percent to 6.43 percent while the raw coal ranging from 6 mm to 10 mm. The results show that, the dense-medium shallow-slot separator has great separation ability for 13 mm to 6 mm slack coal. The application of flip-flop screen in Xieqiao and Zhangjibei coal preparation plant is well, the classification efficiency is above 80 percent.