Stripping을 이용한 고농도 암모니아함유 폐수처리

Abstract

The objectives of this study were to examine the applicability of ammonia stripping process for the removal of highly concentrated ammonia nitrogen in the plating wastewater and to recover removed ammonia nitrogen. In this study, the feasibility of a packed tower ammonia stripping for ammonia nitrogen removal and recovery from ammonia in plating wastewater. The effects of operating variables such as hydraulic loading, pH, air flow and operation temperature were investigated. The optimum hydraulic loading of stripping and scrubbing unit were 5m/hr. Also, ammonia stripping and scrubbing were efficient at pH 10.5 and 3.5 respectively. At the pH of 10.5 and with and air flow rate of 20 L/min, it took approximately 3.8 hr to achieve 90% ammonia removal efficiency in stripping unit. At low temperature(25℃) ammonia removal efficiency was low and was directly dependent upon pH and air flow rate. However, it was possible to achieve high ammonia removal efficiency at elevated temperature(35℃, 55℃). At the waste water temperatures of 35℃ and 55℃, with the pH of 10.5 and air flow rate of 20 L/min. it took approximately 6 and 3.8 hr to achieve 90% ammonia removal efficiency, respectively. On the other hand, the recovery of ammonia in scrubbing unit was slightly decreased with the increasing temperature, due to the reduced solubility of gas at high temperature.