Experimental study on purification and treatment of coal mine water by non-submerged ultrafiltration technology

Non-submerged ultrafiltration(NSUF) technology was used to purify coal mine water. The field tests were carried out on the operating parameters and performance of NSUF ceramic membrane, membrane pollution removal, ultrafiltration concentrated water flocculation with chemicals, and sludge pressure filtration dehydration performance. Under the condition of controlling the ultrafiltration water yield of 70%, the combination of NSUF “membrane surface flow” operation mode and on-line physical cleaning could remove the filter layer blockage and membrane pollution, restore the membrane flux and transmembrane pressure difference, and realize the continuous and stable operation of NSUF device. After adding PAC and PAM, the sedimentation ratio of 30% concentrated water produced by ultrafiltration concentration reached 4.3%, and the clarified liquid returned to the ultrafiltration unit. Flocculated sludge was dewatered by plate-and-frame filter and the water content of filter cake was about 75%. After the combined proce