Abstract: A new type of inorganic polymer coagulant polysilicate aluminiumferric (PSAF) was prepared from
coal gangue and pyrite slag and used as coagulant in the treatment of dyeing effluent , aiming at improving the
treatment effect of dyeing effluent with coagulant . The experimental results showed that PSAF had a good
coagulation effect in the treatment of dyeing effluent under the pH value ranging from 6 to 9. The removal rate
of SS , colority and CODcr was 9411 % , 8816 % and 8112 % respectively under such conditions as room
temperature , pH value = 712 and dosage of the coagulant 75 mgPL. In comparison with the conventional
coagulants , such as PAC (polyaluminium chloride) and PFS (polyferric sulfate) , the coagulation performance
of PSAF is characterized by higher settlement rate , smaller sludge volume , lower remains of pollutants in the
treated dyeing effluent and lower cost of treatment