Abstract
The removal characteristic of nitrogen and organic materials in artificial wastewater was studied with the fixed biofilm developed on a ceramic packing media. Especially, this study was focused on the feasibility of simultaneous nitrification and denitrification(SND). The ceramic media was packed to be 30%, 45%, 60% and 70% to investigate a variation of removal efficiency in the reactor. The activated sludge reactor was operated as a control. The organic removal efficiency didn't show large difference among variable packing ratios. but was sustained to be more than 90% in the reactors with 60% and 75% packing ratios, respectively. The 10% of nitrogen removal was same with the activated sludge reactor and average removal efficiencies with regard to each packing ratio were 25%, 25%, 36% and 52%, respectively. Also, SND efficiency was 10% in the activated sludge reactor and showed 35%, 34%, 49% and 71% according to each packing ratio, respectively. The net $NO_3-N$ removal rates was increased from 12.5 mg/L/d to 43.9 mg/L/d accordance with increasing media packing ratios from 30% to 75% in activated sludge reactor. Therefore the ceramic media is expected to do a major role for the formation of aerobic and anoxic zones in the reactor. The optimum packing ratio was 60% to remove SS and organic materials. but the highest removal efficiency of SND and nitrogen was achieved at 75%.
세라믹 담체를 사용한 고정생물막을 이용하여 합성 폐수내 질소 및 유기물질 제거 특성을 연구하였다. 특히, 본 연구에서는 세라믹 담체를 적용할 경우 질산화와 탈질화의 동시 발생가능여부에 중점을 두었다. 담체의 충전율에 대한 처리효과의 변화를 보기 위해 충전율을 30, 45, 60, 75%로 변화시켰다. 비교실험으로 활성슬러지 반응기를 운전하였다. 유기물질 제거효율은 충전율에 따라 큰 차이를 보이지 않았으나, 충전율 60%와 75%인 반응기의 경우 평균 제거율이 90% 이상을 유지하였다. 질소제거효율은 활성슬러지 반응기에서는 10%, 각 충전율별로 평균 제거율이 각각 25, 25, 36, 52%였다. 또한, SND 효율은 활성슬러지 반응기에서는 10%, 각 충전율별로 35, 34, 49, 71%를 나타내었다. Net ${NO_3}^--N$ 제거속도는 활성슬러지 반응기의 경우 12.5 mg/L/day이였 이나 담체가 30% 충전된 반응기에서는 29 mg/L/day, 45%에서는 27 mg/L/day, 60% 에서는 37 mg/L/day, 그리고 75%가 충전된 반응기의 경우에는 43.9 mg/L/day이 였다. 이와 같은 결과로 불 때 세라믹 담체는 반응기내의 호기성과 무산소 구역 형성에 중요한 역할을 한다고 사료된다. SS와 유기물질 제거에 있어 최적 충전율은 60%였으나, 최대 SND 효율은 충전율 75%에서 얻어졌다.