• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.762-769
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• 2018

This study was carried out to examine the improvement plan by analyzing the characteristics of imported wastes, operation rate, and benefits of energy recovery for incineration facilities with a treatment capacity greater than 50 ton/day. The incineration facility capacity increased by 3,280 tons over 15 years, and the actual incineration rate increased to 2,783 ton/day. The operation rate dropped to 76% in 2010 and then rose again to 81% in 2016. The actual calorific value compared to the design calorific value increased by 33.8% from 94.6% in 2002 to 128.4% in 2016. The recovery efficiency decreased by 29% over 16 years from 110.7% to 81.7% in 2002. Recovery and sales of thermal energy from the incinerator (capacity 200 ton/day) dominated the operation cost, and operating income was generated by energy sales (such as power generation and steam). The treatment capacity increased by 11% to 18% after the recalculation of the incineration capacity and has remained consistently above 90% in most facilities to date. In order to solve the problem of high calorific value waste, wastewater, leachate, and clean water should be mixed and incinerated, and heat recovery should be performed through a water-cooled grate and water cooling wall installation. Twenty-five of the 38 incineration facilities (about 70%) are due for a major repair. After the main repair of the facility, the operation rate is expected to increase and the operating cost is expected to decline due to energy recovery. Inspection and repair should be carried out in a timely manner to increase incineration and heat energy recovery efficiencies.

• Journal of environmental and Sanitary engineering
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• v.8 no.2
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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.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.459-465
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• 2007

This study was conducted to calculate the LCC of a apartment complex with a type of heating system, district heating and cogeneration system. For the purpose of analyzing LCC according to size of apartment complex, 500, 1,500 and 4,000 houses of model apartment selected. This research performs design of heating system and the life cycle cost analysis including an initial cost, energy cost, maintenance and operation cost, replacement cost and renovation cost during the project period(15years). According to the calculated results, 1) Initial cost of cogeneration system with 500, 1500 and 4000 houses is higher than district heating system each of 20%, 13%, 12%. 2) In case of cogeneration system, the payback period by electric generation is 5.21, 4.92 and 4.47 years and saving cost was calculated 29 billion won, 94 billion won and 262 billion won after payback period. 3) Cogeneration system LCC was 1.12, 1.07 and 1.06 times larger than district system with the size of apartment complex. According to the case of this study district heating system is more efficient than cogeneration system in terms of the reduction of LCC. 4) Gas Engine Co-generation System is more efficient than other systems because it can collect progressive part from electric charge progressive stage system. However, the efficiency is decreasing because of raising of fuel bills(LNG) and lowering of power rate for house use. Especially the engine is foreign-made so the cost of maintenance and repair is high and the technical expert is short. 5) District heating is also affected by fuel bills so we should improve energy efficiency through recovering of waste heat(incineration heat, etc.). Also, we should supply district cooling on the pattern of heat using of let the temperature high in winter and low in summer.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.125-134
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• 2001

The purpose of this study is to provide basic information for a future countermeasure municipal and to establish several wastes policy after investigating solid wastes from Sunchon City. In addition, this research can be supported to manage of recycling plant and to reuse plant of each wastes. Results are as bellows after checking up and analysis type of waste in Sunchon city Unit solid waste generation rate from single family is $0.50kg/person{\cdot}day$, and total solid wastes are 41.9ton/day. Unit solid waste generation rate from apartments is $0.45kg/person{\cdot}day$, and solid wastes generation is 55.5ton/day. Unit solid waste generation rate from agricultural is $0.22kg/person{\cdot}day$ and total solid wastes are 13.5ton/day. That show total amount of municipal solid wastes from residential are 110.9ton/day. Unit solid waste generation rate from traditional markets is $1.85kg/person{\cdot}day$, and solid waste total volume is 5,400kg/day. Unit solid waste generation rate from small store is $2.03kg/person{\cdot}day$, and solid waste total are 25,101kg/day. Therefore, this show that total wastes are 30.50kg from downtown and commercial area. Solid waste quantity from Industrial area (Factory region) is 8.5ton and in case of school and hospitals are 7.2kg/day and 3.0kg/day. Solid waste amount from Institutional is 6.6kg/day. Food wastes were eliminated from municipal solid wastes as standard 63.4ton/day, and combustible wastes were 126.9ton/day. If it schedule about 5 years (by 2006) as durable year for food wastes treatment plant, it is expected 42.5ton/day for treatment capacity. We can judge that it is effective to be set 2 lines equipment ${\times}25ton/day$ as treatment ability under considering unexpected working condition such as any repair, trouble and an electrical load. If it schedule about 10 years (by 2011) as durable year for food wastes treatment plant, it is expected 150 ton/day for treatment capacity. We can conclude that it is effective to be set 2 lines equipment ${\times}80ton/day$ as treatment ability under considering working condition such as low loaded operating and the repair for incineration.