• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.75-80
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• 2012

Gasification is a therm-chemical conversion process to convert various solid fuels into gaseous fuels under limited supply of oxygen in high temperature environment. Considering current availability of biomass resources in this country, the gasification is more attractive than any other technologies in that the process can accept various combustible solid fuels including plastic wastes. Mixed fuels of biomass and polyethylene pellets were used in gasification experiments in this study in order to assess their potential for synthesis gas production. The results showed that higher reaction temperatures were observed in mixed fuel compared to woodchip experiments. In addition, carbon monoxide, hydrogen, and methane concentrations were increased in the synthesis gas. Heating values of the synthesis gas were also higher than those from woodchip gasification. There are hundred thousand tons of agricultural plastic wastes generated in Korea every year. Co-gasification of biomass and agricultural plastic waste would provide affordable gaseous fuels in rural society.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.357-360
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• 1997

Currently, there is a need for the development of an advanced new technology for Low-and Intermediate-Level Radioactive Waste (LILW) treatment from nuclear power plants. The vitrification and melting technology by the use of the electrical equipments such as induction heater and plasma torch based furnace, along with off-gas treatment are considered as the most promising one of the LILW treatment technology since they can produce a very stable waste forms as well as considerably large volume reduction, which is a world-wide trend to apply for radioactive waste treatment. Korea Electric Power Research Institute(KEPRI) has already completed a feasibility study on LILW treatment and conceptual system design of a demonstration plant to be constructed. For this research, KEPRI selected a cold crucible melter(CCM) for the vitrification of combustible waste, and plasma torch based furnace(PT) for the melting of noncombustible waste, along with off-gas treatment for the volatile radioisotopes such as cesium.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.3
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• pp.175-180
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• 2004

In order to vitrify the combustible dry active waste (DAW) generated from Korean Nuclear Power Plants, a glass formulation development based on waste composition was performed. A borosilicate glass, DG-2, was formulated to vitrify the DAW in an induction cold crucible melter (CCM). The processability, product performance, and volume reduction effect of the candidate glass were evaluated using a computer code and were measured experimentally in the laboratory and CCM. The glass viscosity and electrical conductivity as the process parameters were in the desired ranges. Start-up and maintaining glass melt of the candidate glass were favorable in the CCM. The product of the glass product such as chemical durability, phase stability, and density was satisfactory. The vitrification process using the candidate glass was also evaluated assuming that it was operated as economically as possible.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.1
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• pp.23-30
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• 2012

In the state that re-evaluation of calculating optimum amount of incineration in the future is needed, as considering the amount of waste, increase of heat value and change in floating population in each area in city B, the purpose of this research was to predict optimum available capacity in incineration plant and to study alternatives for the amount of disposal in each incineration plant based on the available capacity that was predicted. As a result of predicting the change in population based on progress of population in city B in the past, it is expected that an overall population is decreasing, but in some areas, population is concentrated due to increased apartment complexes, showing similar figures as the present. Moreover, when predicting the amount of waste through forecasting population, it is considered that the amount of waste by decreased population is also decreasing. However, the amount of combustible component among a total amount of waste is expected to increase, so it is predicted that the amount of incineration and combustible component will be reasonable except D incineration plant, Therefore, D incinerating plant showed 72.7% of rate of utilization of incineration facility compared to 59.1% of national rate. However, if shortfall of waste in the future can be used wisely in other areas, the use of renewable energy using burner useless heat can be maximized.

• Journal of Environmental Health Sciences
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• v.19 no.4
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• pp.51-58
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• 1993

The integrated solid waste management for Seoul Metropolitan city can be established on the basis of the following hierarchy of priorities: 1. Efforts for source reduction should be propelled by both government and citizens to achieve the effects of resource conservation. The adequate production and consumption which are environmentally amenable and sustainable can be induced by the reasonable imposition of deposit money for waste treatment to one-time use products. To accomplish source reduction effectively, the induction of legal and institutional regulation of producer and consumer participation is requisite. 2. For resource recovery, wastes generated should be recycled as far as practicable. Community residents are responsible to separate discharge, the authorities concerned have responsibility of separate collection, and recycling industry should be assissted through tax reduction and financing. Resource separation facilities can be constructed at Kimpo Metropolitan landfill site for wastes not separately collected due to some unavoidable circumstances. 3. Garbage should be composted. Garbage is uneconomical for incineration, because it has high moisture content and low calorie, thus there is no reason for the incineration of garbage even though garbage is classified into combustibles. Composting facilities can be located at sites which are not densely populated and easily accessible to transportation, for example, Kimpo Metropolitan landfill site. Compost produced can be managed by the authorities for the use of fertilizer to a green tract of suburban land and farms. 4. Nonhazardous combustible wastes not recyclable can be utilized for thermal recovery at the incinerators which are completely equipped with pollution control devices. According to the trend of local autonomy and the equity principle of local autonomous entities, incineration facilities of minimal capacity required can be constructed at each districts of Seoul Metropolitan city which have organized local assembly. In case of Yangcheon district, the economically combustible waste quantity is about 260 tons/day which exceeds 150 tons/day, the incineration capacity of existing facility. But, from now on, waste quantity can be reduced substantially by the intensive efforts of citizens for source reduction and recycling and the institutional support of administrative organizations. Especially, it is indispensable for the government to constitute institutional and technological bases that can recycle paper and plastics form 43% of waste generated. A good time for constructing of incineration facilities for municipal solid waste can be postponed to the time that pollution control technologies of domestic enterprises are fully developed to satisfy the standards of air pollution prevention, because the life expectancy of Kimpo Metropolitan landfill site is about 25 years. Within this period, institutional improvements and technological advancements can be attained, while the air qual. ity of Seoul Metropolitan city can be ameliorated to the level to afford incineration facilities. 5. For final disposal, incombustibles and ash are landfilled sanitarily at Kimpo Metropolitan landfill site.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.1
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• pp.5-12
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• 2018

As many local governments have faced increasing conflicts on landfill use and the time of end use, it is difficult to provide an alternative landfill or conclude a consensus of lifespan extension for the existing landfill site. Therefore, the purpose of this study is to contribute improving of the landfill capacity by calculating the resource recovery potentials of landfilled waste previously and in the future by landfill mining. For this, rate of volume increase, weight ratio, and apparent density were adopted as major parameters and their values were calculated through previous cases. The rate of volume increase was calculated to 1.42 by averaging previous cases of three areas. The average weight ratio of soil matter was 45.6% by calculating for the three areas. For the combustible waste and incombustible waste, statistical data can be used. The apparent densities were divided by combustible waste, incombustible waste, and soil matter using an average of two areas value, i.e., $0.35ton/m^3$, $1.40ton/m^3$ and $1.58ton/m^3$. We analyzed the resource recovery potential of Cheongju landfill by using the estimated parameters. The additional landfill capacity was 45% of the existing landfill capacity by recovering landfilled waste by landfill mining. In addition, it is analyzed that the lifespan is extended to 20 years, if the combustible waste of new inputting waste is sorted and combusted for energy recovery and incineration ash, incombustible waste, and soil matter are only reclaimed into the existing Cheongju landfill. It is expected that the methodology and parameters of this study will be used as basic data when resource recovery potential is analyzed for another case study of landfill mining.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.75-78
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• 2006

With the increasing environmental consideration and stricter regulations waste gasification is considered to be more attractive technology than conventional incineration for energy recovery as well as material recycling. The experiment for combustible waste was performed In the fixed bed gasifier to investigate the gasification behavior with the operating conditions in a 5ton/day fixed bed gasifier The experiments of operation with 10-50 hours were carried out to determine the effects of bed temperature and oxygen/waste rat io on the syngas composition, calorific value and carbon conversion. The calorific values of the produced syngas decreased with an Increase of bed temperature because combust ion reaet ion more act ively happened. The syngas composition of wood waste gasification is CO: 34.4%, $H_2: 10.7%,\;CH_4: 6.0%,\;CO_2: 48.9%$ and that of RPF is CO: 33.9%, $H_2: 26.1%,\;CH_4: 10.7%,\;CO_2: 29.2%$. The average calorific values of produced gas were about $1,933kcal/Nm^3,\;2,863kcal/Nm^3$, respectively

• New & Renewable Energy
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• v.7 no.1
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• pp.29-35
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• 2011

The waste treatment fee and energy production effect of Wonju city RDF plant, the first RDF manufacturing plant in Korea, were investigated in the study. All plant operation data, like total weight of received wastes, produced RDF and separated rejects in processes were fully recorded for mass balance calculation of the plant in 2009. Also all consumed oil and electricity were recorded for energy balance calculation. The results showed that the waste treatment fee not including the RDF sales price of 25,000 won/ton-RDF was 116,573 won/ton-MSW and it went down to 105,298 won when included the RDF price. Produced RDF was 40.2% of total received waste in weight. Three components analysis by mass balance calculation of total received waste showed that Wonju city's MSW was 32.4% of combustible, 37.5% of water and 30.1% of incombustible respectively. Energy effect was found that total amount of produced energy was about 4 times more than that of consumed energy.

• Journal of environmental and Sanitary engineering
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• v.13 no.3
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• pp.9-18
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• 1998

An experimental research was conducted to establish primary data for the stabilization assessment of industrial wastes landfill with analysis of waste components and investigation of leachate and gas generation, using three sets of lysimeter as experimental apparatus. Comparing results of lysimeter from data of landfill, it is suggested that lysimeter of this study can be used to accomplish the stabilization assessment of the real landfill site. Moisture content was lower as landfill period was older and combustible component was the highest in lysimeter C. The C/N ratio of waste was 7.4~14.4 and, with the elemental analysis, the theoretical gas generation rate based on the modified Buswell equation was 0.47~0.49 $m^3/kg-dry$ waste in lysimeter C. Considering the C/N ratio of leachate, it is concluded that the addition of carbon source is needed to biodegrade leachate hereafter. Gas generation rate($m^3/kg-dry$ waste) from lysimeter A, B and C was 0.0009, 0.014 and 0.0067, respectively, and different from each other according to the landfill period of wastes. The results in this study show that the biodegradation of microorganism for stabilization of landfill was inhibited and more activated in acidogenic step than in methanogenic of anaerobic degradation.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.4
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• pp.74-81
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• 2008

Due to separate discharge of food waste, large incinerating facilities for municipal waste show the phase change that combustible contents have been increasing while the concentrations of water have been decreasing when wastes are brought in. This phase change of wastes leads to the increase of exothermic value when wastes are carried in, which causes the problems to make the durability of incinerating facilities weak and lower the capacities of them. In accordance with these problems, this study was carried out to present effective plans to operate incinerating facilities as the quantities of municipal wastes of Incheon have been gradually increasing. We examined the problems caused by the phase change of municipal waste in Incheon and managing plans to control the amounts of heat output when intermixed incineration of food waste is conducted. It is concluded that we could carry out the optimized operation of incinerating facilities as well as produce economic effect to reduce processing costs when we conduct the intermixed incineration of food waste and municipal waste, in the trend that the amounts of heat output generated by wastes are gradually increasing. This is because this operation of intermixing incineration contributes to reducing the amount of exothermic heat.