选煤厂转载点诱导气流影响因素的实验研究

Experimental study on influencing factors of induced airflow in transshipment point of coal preparation plant

为了解决选煤厂转载点扬尘问题,结合煤矿生产现场的实际情况,自主设计了一套等比例缩小的转载点诱导气流实验装置系统,分析煤料在转载过程中单位时间下料量,煤料的下落高差,胶带运行速度等因素对产生诱导气流的影响。实验结果表明:导料槽内诱导气流的速度随着料仓下料量的增加呈现幂指数的增长趋势;同时,随着下料槽角度由30°增加到60°时,诱导气流的速度由0.55 m/s增大到0.7 m/s;转载点落差的有限性使煤料下落时处于一个加速阶段,且随着高差的增大,诱导气流增加明显;当单位时间下料量和下料高度相对较小时,胶带运行速度越大,胶带上煤料与周围空气之间的曳力作用越明显,并通过数据拟合出了单位时间下料量、下料高度以及胶带运行速度与诱导气流的定量关系公式。

In order to solve the problem of dust emission in the transshipment point of coal preparation plant,a set of scaling down experiment system on induced airflow in transshipment point was self-designed with combining with the actual situation of production field in coal mine,then the influence of the discharge rate in unit time,the falling height difference,the running speed of belt during the transshipment process of coal on the induced airflow was analyzed. The results showed that the velocity of induced airflow in the guide chute increased exponentially with the increasing discharge rate in the silo. Meanwhile,the velocity of induced airflow increased from 0. 55 m/s to 0. 7 m/s when the angle of discharge chute increased from30 ° to 60 °. The finiteness of height difference in the transshipment point made the falling coal be in an acceleration phase,and the induced airflow increased obviously with the increase of the height difference. When the discharge rate in unit time and the discharge height were relatively smaller,the running speed of belt was larger,and the drag force action between the coal on the belt and the surrounding air was more obvious. A quantitative relationship formula between the discharge rate in unit time,the discharge height,the running speed of belt and the induced airflow was obtained by data fitting.