천연응집제를 이용한 미세조류의 응집특성

Abstract

Although coagulation-flocculation is effective and widely used, existing metal based coagulants have negative effects on the environment and human body. This study tries to reveal the possibility of using plan based natural coagulants to replace the metal based coagulants such as Alum. Chitosan and Polyglutamin coagulants were chosen as natural coagulants for this study and the experiments. Response Surface Methodology(RSM) was used for the design of this research and the dose of coagulant and a range of pH were determined for the experiments by RSM.

The experiments using Chitosan was carried out with a range of pH 4.95~10.0 and coagulant dose 40~160mg/L. Through the optimization process by using RSM, it was found that the optimum condition was when the coagulant dose of 105mg/L at pH 7.3, and the micro-algae removal efficiency(as OD660) was 79.2%.

The other experiments using Polyglutamin was conducted with a range of pH 4.5~9, coagulant dose 10~150mg/L. The optimum condition of Polyglutamin coagulation/flocculation was when the coagulant dose of 115mg/L at pH 7.5, and the micro-algae removal efficiency(as OD660) was almost 100%.

Key word: coagulation/flocculation, Chitosan, Polyglutamin, OD660, pH, coagulant dose