EXPERIMENTAL STUDY ON WETTING COAL BY PRESSURE-SEEPAGE FLOW

To study the pressure-seepage flow regularity in the veins of coal is very important to dust reduction of coal bed by injecting water.In order to mensurate the effect of wetting coal accurately by pressure-seepage flow, the properties of pressure-seepage flow are measured and studied in the present paper with pure water and dust-cohering agent. Several different kinds of coal, which come from three typical mines, are tested with the simulative experiment device. The samples of the coal are prepared according to the National Standard (GB 482-95). The results of the contrastive experiments of the pressure-water (liquid) wetting coal are given in Table 2. The results show that the effect of wetting coal by pressure-seepage flow are greatly affected by the veins of coal and mechanical properties of solution. For different kinds of coal, the effects of wetting using pure water can not meet the demand of coal bed injecting water under low, middle pressure. However, the addition of some substance, such as dust-cohering agent, can change surface tension of water. So the effect of wetting under the same pressure is improved. On the same condition, the effect of wetting can be improved by 0.32~10 times.