A type of animal waste, cow's liquid manure, which is specially high in nitrogen and phosphorus components, was tried to be treated with a combined system including algal culture, $\underline{Daphnia}$ culture, and chemical coagulation in a continuous basis.
The manure was first diluted with water to a proper concentration and algal cells of mixed species were cultured in it. The algae removed 58% and 99% of initial nitrogen and phosphorus in the manure, respectively. On the other hand, the COD content in the waste increased dramatically due to the increase of algae biomass.
The algal cells were then fed to $\underline{Daphnia}$ in the second stage of the treatment system. $\underline{Daphnia}$ could remove about 71% of the COD content in the secondary stage influent. $\underline{Daphnia}$ contained 75% of protein and could be harvested easily using a screen of proper pore size.
At the third stage, the contents of remaining COD, and phosphorus were removed by precipitating with aluminum sulfate. When the precipitation was proceeded under conditions of pH 8.5 and 20℃, the amount of aluminum sulfate needed for optimum precipitation of COD was 100 mg/l, whereas 400 mg/l was needed for 95% phosphorus removal.
Through the whole continuous three-stage system, 95% of the particulate COD and 98% of the phosphorus could be removed, whereas the nitrogen removal was only 72%.
인공 폐수와 소 오줌을 사용하여 조류 배양을 하여 무기태 영양원을 제거하고 생성된 조류 균체를 물 벼룩 배양과 화학적 응결제 처리로 제거하였다.
연속 배양시 99%의 인산과 58%의 질소가 조류에 의하여 제거 되었다. 물 벼룩 배양과 화학적 응결제 처리에 의하여 각각 71%와 90%의 조류 균체가 제거되었다.
세가지 단계를 하나로 연결하여 연속 배양시 조류 균체와 인산 그리고 질소는 각각 95%, 98%, 72% 제거 되었다.
이때 부수적으로 생성되는 물 벼룩은 75%의 단백질 함량을 보여 단백질 원으로 사용될 수 있음을 보여 주었다.