The Effect of Substrates and Nitrate on Biological Phosphorus Release

생물학적 인 방출시 유기물 및 질산염에 대한 영향

  • Min, Kyung-Kook (Department of Environmental Engineering, Chungbuk National University) ;
  • Weon, Seung-Yeon (Department of Environmental Engineering, Chungbuk National University) ;
  • Lee, Sang-Ill (Department of Environmental Engineering, Chungbuk National University)
  • Received : 1999.08.04
  • Accepted : 1999.10.08
  • Published : 2000.01.31

Abstract

In this study, effects of substrates and nitrate on biological phosphorus release in EBPR(enhanced biological phosphorus removal) process were examined using batch test apparatus at anaerobic conditions. The sludge used in this experiments was taken from SBR(sequencing batch reactor) treating swine wastewater at aeration period. Phosphorus release rates obtained with substrates of FSW(fermented swine wastewater), acetate, propionate, domestic wastewater and methanol were 6.19, 5.99, 1.52, 1.2 and $1.03mgP/gVSS{\cdot}hr$, respectively. Those observed with acetate and FSW were 4~5 times greater than those with propionate, methanol and domestic wastewater. Therefore phosphorus release rates were significantly affected by type of substrate added at anaerobic condition. Phosphorus release was greatly affected by concentration of nitrate in anoxic condition. Comparing to acetate, propionate and FSW, phosphorus release was observed after almost completely depletion of nitrate concentration with methanol and domestic wastewater added as substrate. In the cases supplied with acetate, propionate and FSW, phosphorus release rates were less influenced by a nitrate concentration than those with methanol and domestic wastewater.

본 연구에서는 EBPR(enhanced biological phosphorus removal)공정에서 인 방출에 대한 유기물 및 질산염의 영향을 혐기성 조건에서 회분식 실험으로 관찰하였다. 본 실험에서 사용한 슬러지는 축산폐수를 처리하기 위한 SBR(sequencing batch reactor) 공정의 호기성 상태에서 채취하였다. 유기물인 FSW(fermented swine wastewater), acetate, propionate, 도시하수 및 methanol의 인 방출 속도는 각각 6.19, 5.99, 1.52, 1.2 및 $1.03mgP/gVSS{\cdot}hr$이었다. Acetate 및 FSW의 인 방출 속도는 propionate, methanol 및 도시하수보다 4~5배 더 크게 관찰되었다. 따라서 혐기성 조건에서 인 방출 속도는 주입되는 유기물의 종류에 많은 영향을 받는다. 혐기성 조건에서 인 방출은 질산염의 농도에 의해 커다란 영향을 받았다. Acetate, propionate 및 FSW와 비교하여, 유기물로서 주입된 methanol 및 도시 하수인 경우 인 방출은 질산염이 거의 완전히 제거된 후 관찰되었다. Acetate, propionate 및 FSW가 주입 된 경우의 인 방출 속도는 methanol 및 도시하수가 주입되었을 때보다 질산염의 영향을 더 적게 받았다.

Keywords