This study was carried out to recommend the recycling technology from the organic wastes generated in the neighborhood of a dam in Kroea. The order of production of the organic wastes without the suspended materials and energy corps are Chungju-dam(649.9 ton/day), Daechung-dam(525.1ton/day), Hapcheon-dam(485ton/day), Namgang-dam(478ton/day), and Soyang-dam(246.4ton/day). Because livestock excretions and nightsoil were composed of 72 to 93% of the total organic wastes, they should be proferly reflected in the plan of recycling. It was investigated that the biodegradability was 40~80%, biogas production, 0.22~1.70m3/kg VS, methan production, 0.15~1.07m3/kg VS, and methan contents, 63~79%, respectively, in case of the livestock excretions, which constituted over than 50% of organic wastes. Therefore, the appropriate technology for the recycling of organic wastes can be considered anaerobic co-digestion; this technology can create high added value because of using the fuel for new regeneration enery. SCFMR(Semi-Continuously Fed and Mixed Reactor) for an anaerobic digestion reactor was suited for the treatment of organic wastes because the retention time was relatively constant, compared to CSTR(Continuous Stirred Tank Reactor), power consumption was small, and operation and management of reactor was easy and economical.

So many drinking water treatment plants are under various difficulties by new reinforced effluent standards. Since the target turbidity, much higher than annual average, for designing sludge thickener have to be set to confront high turbidity season, the sludge at thickener should be put up for a long time during usual days. So the soluble manganese and chloroform may be formed under the anaerobic environment in the sludge thickener when the sludge retention time is longer with low turbidity. This phenomenon results in difficulties to keep regulatory level of the discharged effluent. For an effort to overcome the problems, a sludge aeration was successfully implemented into the thickening process. As a result, the final effluent quality and sludge volume were much improved; 41 % of manganese, 62 % of chloroform and 35 % of sludge volume. Additionally, effluent quality was improved ; 61 % of Manganese on aeration with pH control and we could make sure of stability effluent quality despite a long sludge retention time. We recommended the standard of installation sludge aeration equipment to nationally supply water treatment plant under effluent water quality problem ; Manganese, Chloroform, etc.

본 논문에서는 혼합골재 종류 변화 및 CGS 치환율에 따른 콘크리트의 내구성 특성을 분석하였다. 실험결과 CGS 치환율이 증가할수록 AE공기량의 영향으로 내동해성은 저하, 조직치밀화의 영향으로 탄산화는 지연되는 것으로 나타났다.