• 유기물자원화
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• 제11권2호
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• pp.66-73
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• 2003

석유화학공장폐수 슬러지를 폐석고와 시멘트, fly ash 및 고화제 등을 배합하여 성형하면 시멘트벽돌 및 보통시멘트의 압축강도 기준을 초과함으로 제조된 고화체는 벽돌, 블록, 경량골재, 노반재 등으로 활용이 가능할 것으로 판단되었다. 실험 결과 다음의 결과를 얻었다. 시멘트량을 전체 중량비의 20%인 1.29kg에서 fly ash/슬러지의 배합비의 모든 조건과 시멘트량을 전체 중량비의 15%인 0.9kg에서 fly ash/슬러지의 배합비가 0.31~0.45일 때, 시멘트벽돌 및 보통시멘트의 압축강도 기준을 초과하였다. 제조된 고화체(제품)의 유해성 평가를 위해서 침출수 중의 $Cr^{+6}$, Cu, Zn, Cd, Pb의 용출농도를 실시한 결과 모든 대상시료의 중금속 농도는 배출허용기준치 이내를 유지하여 유해물질로 인한 문제는 없을 것으로 판단되었다. 고화체를 시멘트벽돌 및 보통시멘트에 준해서 활용이 가능한 제조조건에서 제조원가를 조사하였다. 조사결과 자원화시설의 고화체 제조능력을 연간 약 18,000톤을 기준으로 할 때, 총괄원가 및 톤당제조원가는 각각 678,664천원 및 37,704원으로 조사되었다.

• 환경위생공학
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• 제8권2호
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• pp.65-84
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• 1993

This study reviewed the current status and problems of sewerage system in Korea and then proposed possible methods to correct the problems. Also, evaluation of future development in sewerage system is included. It can be summarized as follows : 1. Investment in sewerage system is relatively low . 0.23% of GNP, Considering that the investment portion is 0.35% in OECD and 0.63% in Japan, it should be increased further. 2. The reasons wily the investment in sewerage system is low can be ' (1) Low priority is given to the investment in sewerage system. Local government builds and operates its own wastewater treatment plant. Local government as well as residents prefer to invest their money in roadwork, housing and parks to in wastewater treatment facilities because of greater investment effects. (2) Besides capital investment, more maintenance cost is needed for sewerage system. Proper operation of wastewater treatment facilities requires a well-trained operator. Because of public conception that operation of wastewater treatment facility is a dirty job, it is difficult to find a well-trained operator. (3) It is difficult to estimate the effect of sewerage system (4) Cost required to build and maintain wastewater treatment facility should be paid by people, who benefit from the facility. People to benefit are sometimes different from people to pay. 3. Advanced treatment is necessary to protect the bay aura and raw water source as well as to prevent eutrophication of lakes and ponds. 4. Wastewater treatment facility were mainly build in big cities during the decade of 1980. Followings should be solved first to expand the facilities. (1) Rapid repair and construction of sewer. (2) Technical development of wastewater treatment . Prevention of efficient and economical wastewater . Development of efficient and economical wastewater treatment techniques . Development of high-efficiency treatment using bioreactor . Reuse of wastewater treatment plant effluent (3) Sludge treatment and disposal . Composting of sludge cakes . Development of techniques to reduce the volume of sludge cake : incineration and reuse of sludge ash and slag. (4) Utilization of wastewater treatment facilities . Construction of community parks or sports families(ie, on the tops of the covered aeration tanks and sedimention tanks) Construction of wastewater treatment facilities under ground and of parking facilities and community parks above ground. (5) Education of wastewater treatment personal.