1차 처리장에 응집제를 이용한 하수의 화학적 처리 = Pilot Plant Study for Chemical Upgrading of the Primary Treatment Sewage Plant

다국어 초록 (Multilingual Abstract)

A chemical pretreatment for municipal sewage water was evaluated in a pilot system using a coagulant of Hi-PAX to remove the organics/inorganics particles of the receiving waters. As a result, the organic composition of a turbid water consisted typically of an about 70% of the insoluble organic matters, suggesting that a chemical treatment can be a good tool for removing them and consequently enhancing the treatment efficiency at a given residence time. The result from jar test equipped with a automatic controller showed that the optimum rapid and slow mixing time of highly charged metal ion complexes Hi-PAX with raw sewage water was around I and 20 to 30 minute, respectively. A rapid mixing at the dosing point was of paramount importance to enhance the treatment efficiency. When Hi-PAX 50 ㎕/ℓ was used as a precipitation agent in the lst precipitation system, the total removal rate of suspended solid was enhanced up to 90% which is correspondingly equivalent to the data obtained from the existing activated sludge method. Also, chemical treatment represented 80∼85% removal rate of P since it is very preferable to form AlPO₄, or other complexes, while activated sludge method was below 50%. But, such benifits were not observed in the removal of nitrogen. From our pilot test, conclusively, a chemical pre-treatment method was a recommendable candidate that can be applied for upgrading a sewage plant to be expanded or constructed.