The rapid industrial development is facing problems due to the energy depletion in Korea. Therefore, it is necessary to develop alternative energy sources. Alternative energies like bio-fuels can be produced using waste fuels, so it is eco-friendly. Since the organic waste has been banned to dump in landfill and ocean, one of the most practical methods currently used to reduce organic waste is composting or feed stuffing. Converting organic wastes into useful energy sources may contribute to protecting environment as well as developing alternative energy sources. In this study, bio-coal was made agricultural by-products to solve the problems of energy shortage. Bio-coal of hydrothermal carbonization can be one of the solid sources in energy production by using organic waste. By the way, the purpose of this study was the energy assessment of bio-coal made from agricultural by-products. In terms of utilization of bio-coal, it can be applied to bio-SRF.

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With expanding economic growth, the consumption and changing period of electronics products have increased rapidly last a couple of decades in Korea. A refrigerator generally contains 10% of polyurethane. Since the amount of used refrigerators collected at recycling facilities of E-wastes has increased since
2007, the generation of polyurethane waste has also increased. Polyurethane recycling technologies have been investigated such as polyol production and sound-absorbing materials, which are not commercialized yet due to high cost of the technology. However many kinds of plastic wastes are being used as SRF (solid
refuse fuel) like RDF (refuse derived fuel), so polyurethane in E-waste could be utilized as valuable fuels. In this study an attempt to fabricate pellet type of SRF from polyurethane waste was conducted to use them as fuels. The basic characteristics of polyurethane such as elemental composition, thermal
properties and proximate analysis were carried out to assess whether they could be used as fuels or not. Using a fixed bed test reactor, gasification experiments were also conducted at the temperature of 1,000 ºC by measuring exhaust gas compositions and gas pollutants.

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With the booming of economy, consumption of electronic products have increased rapidly and so do the generation rate of electronic waste. A common type of electronic waste in the final stage at recycling facilities is polyurethane. Polyurethane recycling technologies have been investigated for polyol production and sound-absorbing materials, which are not commercialized yet due to high cost of the technology. However many kinds of plastic wastes are being used as SRF (Solid Refuse Fuel) like RDF (Refuse Derived Fuel), so polyurethane could be utilized as valuable fuel, since it has higher heating value and low hazardous contents. For study purpose, gasification experiment was conducted on pellet type SRF made of polyurethane at 1,000 °C temperature using a fixed bed reactor. Environmental assessment on polyurethane gasification residue was also performed in order to verify whether they are hazardous for environment or not. This paper discuss the results of leaching test and the loss of ignition test conducted on polyurethane gasification residue.

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Torrefaction can be used as a pretreatment process for pyrolysis and gasification as it helps in enriching the feedstock. In this work, pyrolysis experiments on torrified Larix saw dust was conducted. The effect of pyrolysis temperature on yield, HHV and moisture content of bio-oil are investigated in this work. The quality of bio-oil generated from torrified biomass is also compared with bio-oil from raw(untorrified) biomass. It was found that the increase in temperature decreased the yield and moisture content of bio-oil. However, the HHV of bio-oil was significantly improved with respect to temperature. It was also found that the quality of bio-oil from torrified biomass was superior than from raw biomass

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Industrial revolution that make an impact on the development of industrial based economy, human consistently consumed fossil fuel to develop heavy industry and production. As a result, possible time of using fossil fuel including oil and coal is less than 100 years. So, using renewable energy is inevitable. Specially waste and biomass, which are major sources of renewable energy (about 80% of renewable energy supply in Korea).
In this study, we conducted assessment about fluff type SRF for waste to energy. And, we selected other samples for comparison analysis. Categories of other samples were biomass and fossil fuel.
We conducted thermal characteristics analysis about samples. Thermal characteristics analysis include elementary analysis, TG analysis, HHV analysis and proximate analysis. These analysis help to conduct assessment thermal characteristics. And this result was used for thermal process like incineration, gasification and pyrolysis. TG and proximate analysis was conducted by TGA-701(LECO co.) and HHV analysis is conducted by AC-600(LECO co.) and Dulong equation.
In this study, we conducted assessment for fluff type SRF and if SRF show good result, we will apply thermal process like incineration and gasification in future study.

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Part of methane generated in waste layer is oxidized at cover soil. Threre were increasing doubt on IPCC default value (0 or 0.1). Oxidation of methane in cover soil is affected by various environmental factors. Therefore, it is recommended to develope site specific oxidation factor. In this study, oxidation factor is estimated using field monitoring results. 14 and 42 samples are collected at vent-pipes and surface, respectively in one MSW landfill in Korea at Apr. 2011. The oxidation factor is estimated based on CH4/CO2 ratio by volume. The oxidation factor showed 0.043 and 0.966 when means and medians are used, respectively. When the one extreme value is ignored, the oxidation factor changed into 0.634 and 0.988 when means and medians are used, respectively. For more accurate oxidation factor, seasonal and temporal variations are needed to be characterized.

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Mercury (Hg) is a persistent environmental pollutant with high toxicity. In order to understand the fate of Hg in landfill site, core sampling in three positions was conducted in a landfill site. Total Hg were determined by MA2000 system and total microbial DNA was extracted from 0.5 g sample using Extrap Soil DNA Kit Plus ver. 2. So as to understand the co-existing element in the core samples, X-ray fluorescence (XRF) spectrometer was used. In the three positions, the total mercury concentration is presented to be lower than that in deeper places approaching the ground surface, and shows a high concentration between 5-15m. The hgcA and merA genes were detected in the surface layer and the deeper layer, but the merB gene was not detected in the all layers. Fe was detected uniformly in all depth while S existed mainly in 6-9m and 15m depth, both of which are concerning the bacterial activity regarding Hg speciation. 

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This paper presents the waste volume calculation method using the point cloud of the surface of three dimensional objects based on 3 dimensional (D) laser scanner which was designed and fabricated for waste volume measurement. In this paper, we proposed the waste volume calculation method using the point cloud of the surface of three dimensional objects based on 3D laser scanner which was designed and fabricated for waste volume measurement. This study improved the accuracy of measuring point clouds by using DD motor than prototype 3D scanner, which was based on AC servomotors. The proposed system periodically collects the volume of the waste from the landfill facility and sends it to the GIS in the landfill facility.

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The aim of this study is to investigate the possibility of measuring the methane emission flux using surface methane concentration and gauge pressure byanalyzing the influence of gauge pressure on the methane emission flux and surface methane concentration, as well as the correlation between the methane emission flux and surface methane concentration. Consequently, when the surface methane concentration and the surface gauge pressure are measured simultaneously, the methane emission flux can be calculated using Darcy’ law. Furthermore, measurement data can be processed into a single whole site flux rate using geospatial interpolation techniques, such as inverse distance weighting (IDW) and ordinary kriging.

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In Japan, a common method of treating waste incineration fly ash prior to disposal is using chelating agents (chelate), chemical organic compounds that can immobilize the heavy metals in the fly ash and prevent their leaching into the environment. The objective of this study is to deepen the understanding of how mercury in waste incineration fly ash is immobilized by chelate-complexation. Three factors have been studied thus far, namely, chelate/mercury ratio, chelate storage time and the effect of co-existing ions. Standard mercury chloride (HgCl₂) and chelate solution were mixed at an initial Hg concentration of 100 μg/L with chelate-Hg ratios ranging from 0.01 to 10. The solutions were then tested for free Hg using a mercury analyzer using tin(II) chloride as a reducer to convert any free Hg, which is not bound by the chelate, into gaseous elemental Hg. For the co-existing ionic effect study, ion-Hg ratio method was similarly adopted. Investigations have found that high chelate concentrations exceeding a ratio of 3 promoted the increase in free Hg. Moreover, co-existing ions such as Ca²⁺ and Mg²⁺ were found to have reduced chelate-mercury complexation. Chelate storage time, however, does not affect complexation efficiency.

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