2005년부터 음식물류폐기물의 직매립이 금지됨에 따라 이에 따른 처리수단으로 자원화(민간 사료화, 공공퇴비화 위주)시설을 많이 설치하여 운영하였다. 하지만 음식물류폐기물을 이용하여 생산된 사료와 퇴비에 대한 사용자들의 부정적인 인식으로, 생산된 부산물이 다시 폐기물로 되는 악순환이 지속되어 왔다. 또한 런던협약에 의해서 2012, 2013, 2014년에 하수슬러지, 음폐수, 축산분뇨 및 하수슬러지 등 유기성폐기물의 해양배출이 금지됨에 따라 고농도의 유기물을 육상에서 처리해야 했기 때문에 부수적으로 바이오가스를 얻을 수 있는 혐기성 소화에 많은 관심을 갖게 되었다. 그러나 많은 지자체에서 혐기성 소화의 이해와 운전기술의 부족으로 시설 운영에 실패 또는 어려움을 겪고 있는 실정이다. 이러한 문제를 해결하기 위해서, 음식물류폐기물과 음폐수의 혼합소화 운전을 하고 있는 대전광역시 내 바이오 에너지화 시설의 혐기성 소화 효율을 실험적으로 분석하고 향후 유기성폐기물의 혐기소화를 이용한 처리 가능성을 살펴보았다. 음식물류폐기물과 음폐수의 총 반입량은 평균 353.17 ton/day이며 그 중 296.47 ton/day이 혐기성 소화조에 투입되었으며 나머지 56.7 ton/day는 매립처리하는 것으로 측정되었다. 시설 내 중간 저장조, 혐기성 소화조, 안정화조의 경우 평균 TS 제거 표율은 72.5%, VS는 80.2%로 측정되었으며 평균 바이오 가스 발생량은 26,450 Nm3/day, 이중 CH4 함량은 63.83%로 측정되었다. VS당 바이오 가스 및 CH4 발생량은 0.77 Nm3-biogas/kg-VS, 0.49 Nm3-CH4/kg-VS로 측정되었으며, VS/TS 비는 중간 저장조, 혐기성 소화조, 안정화조에서 각각 87.0%, 72.5%, 62.5%로 나타났다. 이와 같은 결과를 기반으로, 바이오 에너지화 시설 내 혐기성 소화조 및 안정화조에서 메탄생성세균이 활발하게 성장하고 있어 소화조 효율이 높은 것으로 판단되었다.
Since 2005 the landfilling of food waste has been prohibited, and many recycling facilities (private, domestic, animalfeed conversion, public composting) have been constructed and operated as waste-treatment centers. However, due to the negative attitude of users on the domestic animal feed and compost produced from food waste, the byproducts of waste have created a vicious cycle, needing treatment themselves. In addition, the London Convention prohibited the discharge of organic waste such as sewage sludge into the ocean in 2012 and of food-waste leachate in 2013. An alternative to landfilling and incineration is to treat biomass with anaerobic digestion. However, the anaerobic-digestion efficiency of the Daejeon City bioenergy facility, which has adopted a mixed digestion process of food waste and food waste leachate, has not been reproduced in other municipalities due to a misunderstanding of anaerobic digestion and a lack of operating skill. Thus, the anaerobic-digestion efficiency of the bioenergy facility in Deajeon is analyzed, and it provides basic information for the anaerobic co-digestion of organic wastes.
Global increase in energy consumption has been known to cause the depletion of fossil fuels, and results in the increase of coal and oil price. Recently, waste to energy policy has received attention more and more, Korea imports approximately 97% of its total energy consumed, and there is an urgent necessity for the development of alternative energy source. Domestic waste management policy aims at zero waste community, which can be explained as the concept of 4R. The 4R consists of existing 3R (Reduce, Reuse and Recycle) and Recovery policies. Conversion of waste to energy, a form of renewable energy, has been known as an effective alternative for the increasing energy crisis. In this study, waste wood generated in D city was investigated as one of the alternative energy source. Expecially, the conversion of waste wood to solid refuse fuel (SRF) as an energy source was focused on. As an initial step to evaluate the applicability of waste wood as the alternative energy source, the waste wood sample were characterized by a proximate analysis and element and heavy metal contents analyses. In addition, heating values of the waste wood were calculated by presumption equation and Dulong's equation, and measured by bomb calorimeter. In summary, waste wood can be considered as one of the alternatives for effective energy source by meeting Korea standards for the quality and grade of SRF such as in lowheating values, contents of moisture, sulfur, and chlorine, and heavy metal contents
Recently, many countries have been interested in waste-to-energy policy and technology due to the economic crisis from high oil price and the demands on securing the sustainable energy sources. As one of the efforts to achieve the sustainable society and maintain low impact of global warming in Korea, the act on the promotion of saving and recycling resources was enacted to implemetnt the effective reduction of waste at source level, reduce, recycling and recovery of waste to energy. Attaining an efficient recovery of waste heat in a cogeneration plant from incineration facilities is important as a resource recovery of waste to energy. In this study, the waste heat recoveries changed by reducing feed pressure in incineration conditions were analyzed. As results, changing the operating condition in steam header resulted in stable heat supply and increase of waste heat recovery.