Search / Korean Journal of Chemical Engineering
HWAHAK KONGHAK,
Vol.20, No.4, 293-300, 1982
2단식 복합 생물산화에 의한 폐수처리
Wastewater Treatment Using a Dual Biological Reactor System
완전혼합식 반응조와 충진탑 반응조를 수직으로 연결한 새로운 형태의 폐수처리 장치를 고안하였다.
4.16 l의 완전혼합 반응조는 내부에 원통형의 유로를 설치함으로써 자동적으로 혼합이 되도록 하였고, 둘째단으로 가기 전에 슬러지가 재순환되도록 하였다. 충진탑의 부피는 1.84 l였으며 Raschig ring으로 충진하였다.
4, 7, 10, 15 시간의 네가지 체류시간과 292, 675, 1300 mg/l COD의 세가지 유기물 농도에 대하여 각각 실험하였다. 유기물 부하1.6-1.9 kg COD/m3·day에서 90 % 이상의 처리효율을 보여주었는데 충진탑의 마무리효과는 일단 폭기조의 배출류를 기준으로 약 70 %를 나타내었다. 슬러지 발상률은 gCODekd 0.21∼0.31 g으로 다른 공정에 비하여 낮았으며, 폐슬러지의 SVI는 최적부하에서 26.2-36.6이었다.
A new dual biological reactor system for wastewater treatment was developed by combining CSTR and PBR. A circular tank of 4.16 liters with a concentric draft tube was used for the first stage and a column of 1.84 liters packed with Raschig rings was vertically attached. By arranging two reactors in one column, it is unnecessary to install a separate sludge settler for recycle.
The process was operated with various combinations of four retention times (4, 7, 10, 15 hours) and three organic concentrations (292, 675, 1300 mg/liter COD) with synthetic sewage.
It was found that the process was capable of removing more than 90 % of COD under organic loadings of 1.6 to 1.9 kg COD/m3·day. Results for polishing in PBR showed that about 70 % of the influent COD from CSTR was removed and the effluent SS was maintained less than 30 mg/liter. The sludge yield was 0.21 to 0.31 g SS/g COD removed, an the SVI for an optimum organic loading was in the range 26.2 to 36.6.