다양한 중금속이 인 축적 미생물 (Pseudomonas sp.) 의 생장과 인 제거에 대한 효과

Abstract

The remove of phosphate (P) in the wastewater is essential for the prevention of eutrophication in the river and stream. This study was initiated to evaluate the effect of the various heavy metals on the growth of Pseudomonas sp., which was well known as phosphorus accumulating microorganism(PAO's) in the EBPR(Enhanced Biological Phosphorus Removal) process. The five heavy metals used in the study include Cu, As, Zn, Ni, and Cd. The removal efficiencies of phosphorus by Pseudomonas sp. at 25℃, 30℃, and 35℃, were 76.29%, 90.61%, and 74.19%, respectively. Any decrease in the P concentration was not shown in the untreament with no inoculation. The only 8% of the initial P concentration was decreased in the treatment with inoculation of dead cells. However, about 90% of the initial P concentration was removed in the treatment with the inoculation of Pseudomonas sp. The IC50 (median Inhibition Concentration) values of Pseudomonas sp. for the Cu, As, Zn, Ni, and Cd were 2.35, 11.04, 1.80, 4.92, and 0.24 mg/L, respectively. Based on the results obtained, the sensitivity of for the hevay metals used were in the following order: Cd> Zn> Cu> Ni>AS. It appears that the phosphorus removal efficiencies by Pseudomonas sp. was correspondingly decreased as the concentrations of heavy metals was increased.