RESPIRABLE DUST CONCENTRATION DISTRIBUTION MODEL ON LONGWALL FACES - MULTIPLE DUST SOURCE APPROACH

A mathematical model is developed for description of the dust concentr ation distribution on the longwall faces of coal mines involving multi ple dust sources of various particle sizes. Longwall mining is an effi cient and productive coal-mining method. However, it generates a large quantity of respirable dust in the working area during the shearing a nd transportation of coal. Multiple dust sources on the longwall face make dust distribution prediction very difficult. In this paper, the p rimary sources of respirable dust and transportation of dust particles on a longwall face are determined. The dust particle size distributio ns at various locations of the longwall face are analyzed, classified and incorporated into the dust distribution model. General trends of d ust concentration obtained at different working positions on a longwal l face are discussed. The mathematical model takes into account the ch aracteristics of airflow, the effect of particle size, various dust so urces, and the mechanisms of dust transport along a longwall face. It predicts the dust behaviors and dust distribution in the longwall mini ng atmosphere under various operating conditions. Computer programs ba sed on the respirable dust distribution model are also developed. The predicted results are compared with the field data from several longwa ll faces.