In order to increase the removal efficiency of Fe2+ in acid coal mine water,the coagulant sedimentation without aeration oxidation was carried out to treat acid coal mine water. The effects of pH value and coagulant dosage on the Fe2+ removal efficiency is investigated.The results show that,the Fe2+ removal rate reaches 99. 88% when the pH value is 8. 5 which is adjusted by 5% lime emulsion. So 8. 5 is the optimum pH value. First add 1 mL 0. 1% PAM to the acid coal mine water,then adjust the pH value to 8. ...