Alum와 PAC을 이용한 하수처리장의 총인 저감 효율 향상을 위한 운영개선

This study is to minimize the cost of facility investment and to stabilize the water quality and to reduce the cost in the public sewage treatment facility. A simple test was carried out in the field to estimate the amount of ploy aluminum chloride (PAC) and for the purpose of determining injection of PAC. Removal of total phosphorus (T-P) showed 21.9 % reduction efficiency at 5 mg/L of PAC injection, and 35.9 % and 36.9 % reduction of 7.5 mg/L and 12 mg/L, respectively. After confirming the data of January 2016 before the injection of PAC and January 2017 after injection, T-P reduction checked the I public sewage treatment plant of effluent data. The maximum effluent water quality of T-P in January 2016 was 0.187 mg/L, and the maximum effluent water quality of T-P in January of 2017 was 0.051 mg/L, which was relatively low effluent water quality. In addition, the operation cost is relatively decreased when PAC is injected only during the winter season than when the PAC is injected during the year. Therefore, in order to overcome the degradation of coagulation efficiency at low temperature water. It was concluded that PAC was injected only in winter season to improve water quality and reduce operating cost.