Usage of drinking water treatment plant sludge as a coagulant in wastewater treatment

Sludge originating from drinking water and wastewater treatment plants may have different contents depending on the treatment processes, the composition of the water to be treated and the treatment performance of the plants. Removal of these wastes by improper disposal methods may cause new pollution problems in environments. For this reason, it is important to apply economical and environmentally friendly methods in the removal of sludge. Re-use of sewage sludge in different areas will contribute to both the elimination of the existing waste problem and the reduction of raw material consumption in different areas in environmental and economic terms. In this thesis, the efficiency of the sludge released in Konya drinking water treatment plant in the treatment of metal plating wastewater, synthetic gray water and humic acid solution by coagulation-flocculation process was investigated and compared with commercial aluminium chloride hydroxide (ACH). As a result of the use of sludge and ACH, the removal of AKM from metal coating wastewater was 92.3-96.0%, 92.8-96.1%, and zinc removal was between 79.7-95.9% and 74.8-95.7%, respectively at pH 8. In synthetic gray water treatment, COD removal was determined as maximum 50% in sludge use and 92.9% in ACH use. In humic acid solution treatment, maximum color removal was determined as 26.5% and UV272 removal was determined as 29.9% in sludge usage at original pH value (7.65), while these values were determined as 96.6% and 91.3%, respectively, in ACH usage.