• Environmental Engineering Research
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• 제24권4호
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• pp.529-542
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• 2019

Nowadays, drying methods for municipal solid waste quality improvement have been adopted in the developed and developing countries to valorize wastes for a renewable energy source, reduce dependency on fossil fuel and keep safer disposal at landfills. Among them, biodrying, biostabilization, thermal drying and solar drying are the most common. Drying of municipal solid waste could offer several environmental and economic benefits. Therefore, this review highlighted the drying methods for municipal solid waste quality improvement around the world and compared them based on the reduction of moisture, weight and volume of municipal solid wastes against drying temperature and time by using statistical analysis. It was observed that the drying temperature of different drying methods accounted for 115 ± 40℃ for thermal drying, 59 ± 37℃ for solar drying, 55 ± 15℃ for biodrying and 58 ± 11℃ for biostabilization. Among the drying methods, thermal drying provided the shortest drying time. The moisture reduction, weight reduction, volume reduction and heating value increase of municipal solid waste could vary with drying temperature and time. Finally, the benefits and drawbacks of different drying methods were specified, and recommendations were made for the future efficient drying.

• 유기물자원화
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• 제16권4호
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• pp.74-81
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• 2008

현재 전국 대형생활폐기물 소각시설은 음식물류폐기물 분리배출로 인하여 반입폐기물의 가연분 함량은 증가하고 수분 함량은 감소하는 성상의 변화를 보이고 있다. 이러한 폐기물 성상의 변화는 반입폐기물의 발열량을 증가시켜 소각시설의 수명 단축 및 가동률을 저하시키는 문제를 발생시키고 있다. 따라서 본 연구는 인천광역시의 점증하는 생활폐기물에 대한 효율적인 소각시설운영방안을 제안하기 위한 연구로써 인천광역시 생활폐기물의 성상변화가 소각시설에 미치는 문제점과 음식물류폐기물 혼합소각에 의한 발열량 관리방안에 대하여 검토하였다. 그 결과 음식물류폐기물과 생활폐기물의 혼합소각은 폐기물의 발열량이 지속적으로 상승하고 있는 추세를 감안할 때 발열량의 저감 역할을 함으로써 소각시설의 적정운영과 동시에 음식물류폐기물의 처리비용을 절감 할 수 있는 경제적 효과를 기대할 수 있을 것으로 판단된다.

• 한국폐기물자원순환학회지
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• 제35권8호
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• pp.731-743
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• 2018

This study was performed to test the feasibility of thermophilic ($55^{\circ}$) co-digestion of municipal sewage sludge and food wastes. The management variables of co-digestion were the mixed ratios of municipal sewage sludge and food waste hydraulic retention times (HRTs). During the operation of thermophilic co-digestion, the reactor pH ranged from 7.0 to 7.5 and the reactor alkalinity remained above 3,200 to 4,000 mg/L as $CaCO_3$. The volatile fatty acids concentration increased as the HRT shortened from 20 days to 10 days and the mixture ratio increased to 1:4, but did not reach toxic levels for co-digestion of sewage sludge and food wastes. Methane productivity increased gradually as the organic loading rate increased. Maximum methane productivity reached 1.03v/v-d at an HRT of 10 days and at the mixture ratio of 1:4. The TVS removal efficiency decreased from 70.6% to 58.3% as the HRT shortened from 20 days to 10 days. TVS removal efficiency ranged from 57.0% to 77% during the entire operation. It is likely that thermophilic co-digestion of sewage sludge and food wastes is a very effective method both to environmentally treat food waste and to economically produce gas for energy.

• 산업기술연구
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• 제22권B호
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• pp.103-108
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• 2002

This research was performed to investigate the generation and physico-chemical characteristics of municipal solid wastes. The results were as follows: i) The generation rate and bulk density were 0.157 kg/cap/d and 147.8 g/L in residential zone, respectively. In non-residential zone, the generation and bulk density were 1.71 kg/cap/d and 85.6 g/L, respectively. Consequently, bulk density of non-residential zone was lower than that of residential zone. ii) The wastes consisted of 90% of combustibles and 10% of incombustibles in residential zone. And the wastes from non-residential zone was composed 85% of combustibles and 15% of incombustibles. iii) Water content was estimated at 47~50% in residential zone and restaurants. In non-residential zone, except restaurants, water content was in the range of 10~30%. Ash content was nearly 10% in overall zone.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.489-493
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• 2001

Big cities in Japan have serious problems due to the shortage of new reclaimed land for municipal wastes. If harmful heavy metals such as cadmium, lead, copper and etc. are contained in the municipal waste combustion residues, they are not able to fill up according to the environmental law in Japan. In this study, the removal of heavy metals in the fly ash (EP ash) was dealt with chloridizing vaporization method. EP ash as a non-hazardous materials is utilized as covering materials, road bed, and building materials.

• 환경위생공학
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• 제10권3호
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• pp.29-34
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• 1995

This study was on the characteristics and heating values analysis of municipal solid wastes according to the volume- rate garbage collection system in Busan. Each waste sample was analyzed to obtain physical composition, proximate analysis, heating value, chemical composition. And the heating value were compared with those of the past waste collection system. The average physical composition of A.P.T. area was food waste 54.0~65.7% , while that of common residence was food waste 57.9~61.2% . The density of solid waste were largely different for site and the highest densities of waste was $399.6kg/m^{3}$ from Market. The low heating value of waste from residence site was 996.9kca1/kg~1, 238.1 kcal/kg which was lower than 1, 000kcal/kg~1, 800kca1/kg of the past wastes. These difference was mainly due to the difference of moisture content and the amount of vegetables.

• 환경위생공학
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• 제13권3호
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• pp.93-101
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• 1998

This study was carried out to investigate and analyze the citizen's attitude for the issue of the municipal solid wastes in Miryang city. The waste generation rate was decreased by 56% compared with 1991, and 71.8% of generated wastes were treated by landfill method. 61.6% among respondents were contacted waste problem by TV and the majority of respondents felt seriousness of food-waste problem. The majority of people felt that waste discharge decreased after "volume-base charge system" and 71% of total respondents were burdened down with use of volume-base charge envelope. The greater part of citizens answered that they experienced damage due to wastes and satisfied with the collection system but they recognized the necessity of the establishment of collection system and increase of cleaners must be nessary.

• 한국환경과학회지
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• 제3권4호
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• pp.417-425
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• 1994

Leachate from municipal landfill site is known to be hard to treat because it commonly contains various toxic material and heavy metals. In addition, portions of biodegradable organic substances in leachate are decreasing in the course of wastes stabilization, which is one of the critical reason for inefficient biological treatment at the end stage of landfill site operation. So this study was conducted to examine the feasibility of municipal lanuill leachate pretreatment using electrolysis. The optimum electrode combination was made. The optimum electrode combination was found to be lead and graphite.

• 유기물자원화
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• 제9권4호
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• pp.125-134
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• 2001

순천시 생활계폐기물의 배출특성을 제시하고 장래 폐기물대책을 수립하는 기본적인 자료로 정보를 제공하고자 폐기물별 자원화시설의 용량을 산정하고 재활용시설의 운영관리 및 제반폐기물정책 수립에 활용하도록 하기 위해서 조사분석하여 다음과 같은 결과를 얻었다. 일반주택의 배출량원단위는 0.50kg/인${\cdot}$일로 배출량은 41.9톤/일, 공동주택의 배출량원단위는 0.45kg/인${\cdot}$일로 배출량은 55.5톤/일, 읍 면지역의 배출량원단위는 0.22kg/인${\cdot}$일로 배출량은 13.5톤/일로 나타나 주택지역의 생활계폐기물 배출량은 110.9톤/일이다. 재래시장의 배출량원단위는 1.85kg/상가 일로 배출량은 5,400kg/일이며, 소규모점포의 배출량원단위는 2.03kg/상가 일로 배출량은 25,101kg/일로 나타나 상가지역의 생활계폐기물 배출량은 30,501kg/일이다. 공장지역에서 배출되는 사업장생활계폐기물은 1일 평균 8.3톤, 학교와 병원 및 업무지역에서 배출되는 생활계폐기물의 1일 평균배출량은 각각 7.2kg과 3.0kg 및 6.6kg이다. 생활폐기물 중에서 음식물쓰레기는 평균 63.4톤/일 배출되었으며, 소각대상 가연성폐기물은 126.9톤/일 배출되었다. 음식물쓰레기처리시설의 내구년도를 약 5년(2006년도)으로 계획하면 처리대상량은 1일 42.4톤이 예상되며, 저부하 운전이나 고장보수로 인한 가동중지 등의 문제를 고려하여 처리능력을 25톤/일${\times}$2계열로 설치하는 것이 효율적일 것으로 판단된다. 소각처리시설의 내구년도를 약 10년(2011년도)으로 계획하면 처리대상량은 1일 150톤/일이 예상되며, 저부하 운전이나 고장보수로 인한 소각작업 중지 등의 문제를 고려하여 처리능력을 80톤/일${\times}$2계열로 설치하는 것이 효율적일 것으로 판단된다.

• 유기물자원화
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• 제2권1호
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• pp.3-18
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• 1994

우리나라 도시고형폐기물은 퇴비화에 적합한 조건을 갖추고 있으나, 퇴비화 공정개발이 미약하여 폐기물 퇴비화를 실용화하지 못하고 있다. 폐기물 퇴비화의 실용화를 위하여는 최종퇴비의 질을 높이면서도 대량의 폐기물을 단기간에 처리할 수 있도록 공정제어를 하여야 한다. 이를 위하여 최적온도를 지속적으로 유지하도록 공기공급량을 제어하는 방식(온도제어 공기공급방식)이 있다. 본 연구에서는 우리나라 도시고형폐기물에 온도제어 공기공급방식을 적용하여 퇴비화 과정중의 공정효율과 최적온도를 분석하고자 하였다. 실험결과, 온도제어 공기공급방식이 일정공기공급방식에 비하여 짧은 기간에 분해효율과 건조효과가 높은 것으로 나타났다. 또한 우리나라 도시고형폐기물 퇴비화의 최적온도는 $50{\sim}54^{\circ}C$로 평가되었다.