Vermistabilization에 의한 하수 슬러지와 가축분뇨의 병합처리

Co-treatment of Sewage Sludge and Cow Manure by Vermistabilization

본 연구에서는 지렁이를 이용한 하수슬러지의 안정화시 타 폐기물과의 혼합 가능성을 알아보기위해 가축폐기물중 우분의 혼합비율을 달리하여 부숙에 따른 이화학적 성상변화를 살펴보고 이를 바탕으로 부숙시료에 대한 지렁이의 생존율, 증체율, 부화율 그리고 슬러지 섭취량 및 배설량 등을 평가하였다. 50일 부숙시킨 혼합시료의 이화학적 특성은 pH가 6.9~7.2, 또는 -22~174㎷, 알카리도는 270~1,150mc $CaCo_3$/L로 조사되었으며, 부숙시료에 대한 지렁이 입식실험에서 생존율은 30%, 20%, 10%의 우분혼합구에서 각각 88.3%, 83%, 63.7% 증체율은 각각 321%, 297%, 265%, 부화율은 각각 91%, 76.7%, 66.7%로 나타났다. 50일 동안의 섭취량과 분변토 발생량은 하수슬러지의 혼합비율이 높을수록 감소하는 경향이었으며, 지렁이 한 마리당 하루 섭취량과 분변토 발생량은 20%이상의 우분혼합구에서 각각 0.15~0.18g, 0.11~0.14g으로 나타났다. 이상의 결과로부터 하수슬러지의 vermistabilization 처리시 우분의 혼합비율은 20%이상이 요구되며 슬러지의 병합처리 가능성을 인정할 수 있었다.

The objective of this study was to investigate the effect of cow manure as additive material on the ripening of sewage s sludge for vermistabiJization. The changes of the waste properties by ripening for 50days were observed as a function of the v various mixture ratios of sewage sludge ‘and cow manure. The pH values of the mixture wastes decreased from 7.5-7.67 to 6_ 9~7.2 by the ripening for 50days, and the mixture ratio made dIfferent pH values. The initial value of oxidation-reduction p potential (Eh) of the mixture waste was a negative (-) value indicating an unfavorable condition for earthworm after, but the v values of Eh increased with the opening time. The Increase rate at Eh value was prop$\alpha$rtional to the mixture ratio of cow m manure. The value of alkalinity was also changed into the favorable range for earthworm after 50days except for non-use of 1 the cow manure When the mixture ratio of the cow manure increased from 10% to 30%, the growth of earthworms increased h from 63.7% to 88.3 % tor the survival rate, 265% to 321% for the liveweight increasing rate and 66.7_7% to 91% for hatching f rate of the cocoons. It can be concluded that the proper content of tbe cow manure in the sewage sludge to ensure effective v vermistabilization was over 20%, when the mixture was ripened during 50 days. The quantity of ingestion and 며ectian at 20%-30% was found to be O.15--i.L18g sludge and 0 1l--O.14g solid per capacity earthworm per day, respectively.