Hydrothermal carbonization (HTC) is a highly effective technique for treating lignocellulosic biomass and organic waste of various shapes and moisture content. The solid product of HTC is friable, hydrophobic, and increased in mass and energy densification compared to the raw biomass. also solid product is similar regardless of the type of biomass used. A liquid solution of five carbon and six carbon sugars, along with various organic acids and 5-HMF, is also produced from HTC of lignocellulosic biomass. The gaseous phase product consists mostly of CO2. Solid product has the similar characteristics to low rank coal. The solid fuel characteristics of feedstock was increased with reaction temperature and time via HTC process. However, mass yield was decreased with increasing temperature and time. Therefore, it is necessary to optimize the reaction temperature and time for HTC. The HTC process produces the solid product and a large amount of water. Thus the reuse or treatment techniques of liquid product is necessary. Therefore, potential of biological treatment of HTC liquid product was evaluated.

Incineration allows for the recovery of energy from combustible waste. It would be highly beneficial to society if this heat could be used efficiently. However, due to the difficulties involved with storing and transporting heat energy, consumers would need to live near incineration facilities in order to make efficient use of this heat energy. Moreover, it is usually difficult to achieve a balance between heat demand and supply. For instance, although there is a significant demand for heat in Northern Europe, the demand for electricity in that region is larger than the demand for heat in Central/Southern Europe. Hence, the preferred form of energy recovery differs depending on the nation or regional conditions. However, there are no limitations with regard to electricity because it can be used in a variety of ways. As a result, leading countries such as those in the European Union and the United States have been developing technologies and building facilities to recover electricity. In Korea, stable operation (steam condition 200-300℃, 20-25bar) was given priority over energy recovery because the country’s background with regard to the measure for dioxin is different from that of Europe or the United States. In addition, the produced energy has been mostly self-consumed rather than sold. While Korea is implementing incineration energy recovery, the country’s incineration power generation is considerably lower than that of leading nations. According to the 6thbasic plan for power supply(2013–2027), which was announced in 2013, the government of Korea is planning to secure a power generation capacity of 688 MW (as of 2012, a level of 74 MW was attained) from waste. Accordingly, this paper examined trends and efficiency improvements for incineration power generation in leading countries.

In a mercury leaching test for waste using the Korean Standard Method (ES 06404.1), the pre-treatment process of an eluate is very complicated with a high possibility of contamination and low mercury recovery rate. It is also difficult to analyze multiple samples in a short time and the process generates experimental wastes. Accordingly, a direct mercury analyzer (DMA) applying thermal decomposition gold-amalgamation analysis has been recently used. The method shows a relatively high recovery rate for solid samples without complicated pre-treatment and it can be applied to both liquid and solid samples as the EPA method 7473 does. In order to use the auto-sampler in DMA for analyzing many elution samples from waste, this study checked recovery rates depending on acid solutions and additives during continuous analysis. The result showed a significant drop in recovery and precision except for an L-cysteine added sample. Considering commonly used acid-treatment of wastes, three types of acid solutions (nitrate, hydrochloric acid and sulfate) were chosen for analysis, and precision and accuracy were relatively high in nitric acid solution. It has been determined that accuracy and precision improved when 0.01% L-cysteine was added as an additive and this reduced the impact of continuous measurement. Therefore, during analysis of liquid samples or eluted samples using DMA continuously, introducing suitable additives is necessary depending on pre-treatment method in order to improve accuracy and precision in the analysis of mercury.

The IPCC methodology for estimating methane emissions from a solid waste landfill is based on the first order decay (FOD) method. One emission factor in the model is the methane generation potential (L0) that is estimated from the amount of decomposable degradable organic carbon (DOC) in a solid waste landfill. L0 is estimated based on the fraction of DOC in the waste, the fraction of the degradable organic carbon that decomposes under anaerobic conditions (DOCf), methane correction factor (MCF), and the fraction of methane in generated landfill gas (F). The other emission factor is the methane generation rate constant (k). The IPCC recommended that every country needs to develop country-specific key parameters (DOC, DOCf, k) more appropriate for its circumstances and characteristics. The objective of this research was to investigate the greenhouse gas emission factor (k) and parameters (DOC, DOCf) for wood wastes in a solid waste landfill. To investigate DOC, DOCf, and k for wood wastes, the biodegradable rate of wood wastes was determined by comparing the composition of excavated samples (L-1, L-2) with their fresh ones (F-1, F-2). The DOC values were found to be 48.36% and 45.27% for F-1 and F-2, respectively. It showed that the IPCC default value of DOC for wood wastes is appropriate for estimating methane emission. The maximum DOCf (0.17 and 0.18) or each wood waste excavated from G landfill was found to be lower compared with those for IPCC. The IPCC provided that default values of DOCf 0.5. The k values were found to be 0.0055 and 0.0058 year−1 for F-1 and F-2, respectively. The result confirmed that the biodegradation rate of wood wastes was very slow due to its lignin.

In this study, to understand the current status of solid waste management in China, the author presented generationand treatment status of municipal solid waste in China, and the composition of municipal solid waste in the SouthernChina. Also following important definition and control measures for solid waste management in China were reviewed.(1) The definition of solid waste, (2) Solid waste identification guide, (3) Leaching test for the determination of hazardouswaste, (4) Standard for pollution control on the landfill site of municipal solid waste, (5) Municipal solid waste landfillharmless evaluation criteria, and (6) Twelve Five national municipal solid waste treatment facilities construction plan.

In this study those currently operating SRF (Solid Refuse Fuel) combustion plant were selected for the investigation. The SRF component analysis, and the reaction time to collect contaminants collected and analyzed. As the result, the average caloric value of the SRF was about 8,114 kcal/kg and the result of the analysis was satisfied with the Fuel standard. The SRF could be used as an alternative Coal fuel. However CO, NOx and Dust analysis result was exceeded the emission standard. In case of Hydrogen chloride, high concentration of emission from the facilities was observed. Although normal operation was performed, ineffective the operational management causedt, incomplete blockage of drug injection facilities and personnel management system. To prevent such problems, a regular maintenance of facilities is need to be installed. At the moment applied to the monitoring system (TMS) are installed in waste incinerators with the medium to large capacities, However such as a periodically monitoring system is needed to manage a small solid fuel boliers as well.

The components of municipal solid waste incineration bottom ash produced over 3 million ton every year are similarto the components of geological features, therefore it is suitable to be used as the raw materials of lightweight aggregate.Development of lightweight aggregate using this bottom ash will be helpful to solve landfill and environmental problems.Lightweight aggregate was developed at 1,110oC by using clay, kaolin, bentonite and silica as the raw material to 50%of municipal solid waste incineration bottom ash. Silicon carbide (SiC) was used as a blowing agent. Optimal mixingratio is bottom ash 50%, kaolin 22%, clay 22%, bentonite 6% and blowing agent 0.1%. As the result of quality test,produced lightweight aggregate met the all appraisal standards. The result of heavy metal leaching test was much lowerthan the elution reference value of ceramic manufactures made by using bottom ash.

This research performed physico-chemical analysis of MSW(municipal solid waste) for design and operation ofgasification generation system. The MSW sample was analyzed by proximate, ultimate, heat value method and sampledeach residential type classified apartment, house, urban and rural in by seasonal generation According to statistics of 2010MSW generation in Korea, On average, Namwon generated about 101.4 ton of trash and recycled almost 57.5 ton ofthis material per day, equivalent to a 56.7 percent recycling rate. It was recycled 0.73 kilograms out of individual wastegeneration of 1.29 kilograms per person per day. In 2011, On average, Namwon generated about 46.7 ton without recycledmaterial per day, and individual generation was 0.60 kilograms. It was virtually identical with statistics data in 2010. Inthe physico-chemical analysis results, it was composed of 84.1 percent of combustible and 15.9 percent of Non-combustible. On average, heat value was 2,529kcal per kilogram in condition of LHV and wet. The MSW sample wasincluded 32.0 percent of moisture, 21.9 percent of ash, 26.8 percent of carbon, 14.4 percent of oxygen, 3.7 percent ofhydrogen and 1.3 percent of others. Estimate of technical potential energy of MSW was 1,278 toe per year, equivalentto a 33.3 percent of total potential energy.

This study describes the design and corrosion-resistant materials for a high-efficiency waste-to-energy (WtE) plant. WtEtechnology is one of the most robust and effective alternative energy options to reduce CO2 emissions and to conservelimited fossil fuel resources, which are used by traditional power plants. The recently published 3rd edition of the CEWEP(confederation of european waste-to-energy plants) energy efficiency report demonstrated the energy efficiency criterion(R1 formula) that was introduced in the waste framework directive and has proven to be an incentive for WtE plants inEurope to improve their energy efficiency. The design combines the optimal use of the corrosion resistant properties ofinconel with an efficient boiler design (Amsterdam) and turbine layout. It uses a steam-steam reheater to realize thisefficiency as well as high availability and low maintenance. The high-efficiency WtE plant is an economical choice thatmakes a very positive contribution to sustainable electricity production.

In this study, an accelerated carbonation process was applied to stabilize hazardous heavy metals of industrial solid waste incineration (ISWI) bottom ash and fly ash, and to reduce CO2 emissions. The most commonly used method to stabilize heavy metals is accelerated carbonation using a high water-to-solid ratio including oxidation and carbonation reactions as well as neutralization of the pH, dissolution, and precipitation and sorption. This process has been recognized as having a significant effect on the leaching of heavy metals in alkaline materials such as ISWI ash. The accelerated carbonation process with CO2 absorption was investigated to confirm the leaching behavior of heavy metals contained in ISWI ash including fly and bottom ash. Only the temperature of the chamber at atmospheric pressure was varied and the CO2 concentration was kept constant at 99% while the water-to-solid ratio (L/S) was set at 0.3 and 3.0 dm3/kg. In the result, the concentration of leached heavy metals and pH value decreased with increasing carbonation reaction time whereas the bottom ash showed no effect. The mechanism of heavy metal stabilization is supported by two findings during the carbonation reaction. First, the carbonation reaction is sufficient to decrease the pH and to form an insoluble heavy metal-material that contributes to a reduction of the leaching. Second, the adsorbent compound in the bottom ash controls the leaching of heavy metals; the calcite formed by the carbonation reaction has high affinity of heavy metals. In addition, approximately 5 kg/ton and 27 kg/ton CO2 were sequestrated in ISWI bottom ash and fly ash after the carbonation reaction, respectively.

Recently biodiesel has drawn much attraction as renewable enegy due to its environmental benefits and the fact that it is made from renewable resources. However, the production cost of biodiesel is one of the main hurdle to commercialize it. One of the way to reduce the biodiesel production cost is to use the waste cooking oil as feedstock. In the conventional transesterification process of waste cooking oils for biodiesel production, the presence of free fatty acids and water causes severe problems such as formation of soap and decreasing of catalyst yield. Much effort has been devoted to solve the above problems and one of the promising way is the supercritical methanol treatment which is performed at the methanol supercritical environment (>239.45℃, >8.10 Mpa)one of the serious problems of the application of SCM process for the biodiesel production is the tough operation condition(high pressure, high temperature. In this study, we have studied about the supercritical methanol treatment for the biodiesel production with the soybean waste cooking oil as a feedstock in the present of various heterogeneous solid catalysts such as mesoporous silica and acid-doped mesorpous silica. Biodiesel conversion was increased at more mild opreation condition to the previous studies by using the catalysts. The conversion was more enhanced by modifying the catalysts.

In order to accelerate the biodegradation of easily organic materials in landfilled waste before excavating a closed solid waste landfill and prevent to be dried the landfilled wastes at the same time, this study has suggested the Dual Step Biostabilization System (DSBS), which could inject air with dry fog into its body. In addition, the applicability of the DSBS was estimated by means of field test at a closed landfill. As a result of field test, the reduction of oxygen consumption rate for landfilled wastes (48%) stabilized by air with dry fog was higher than that of landfilled wastes (38%) stabilized by only air. Three lysimeter experiments were, also, performed for the landfilled wastes sampled from the closed landfill. The production of cumulative carbon dioxide for landfilled wastes stabilized by air with dry fog was estimated to be highest (1,144.8 mL). In case of lysimeter that moisture was not introduced was found to be 1,051.9 mL, while another lysimeter that moisture was introduced through horizental trenches was 1,095.8 mL. It is clear that the DSBS can accelerate the biodegradation of organic compounds. In terms of volatile solids, the reduction amount of volatile solids for air with dry fog was higher than that of the other conditions.

Needs for more accurate greenhouse gas (GHG) emission estimation are increasing to prepare for post-Kyoto protocol and emission trading starting from 2015 in Korea. Although GHG emission from landfill is relatively low, uncertainty of methane emissions from landfill is very high compared to the other sectors. Moreover, accurate estimation is needed to design landfill gas collection system and energy generation plant. In this paper, we investigated development methodologies of parameters comprising methane generation potential (L0) which is one of key parameters in methane emission estimation models. DOC included four steps including analysis of waste component, water content, organic carbon content, fossil carbon content. Instead of analysis of organic carbon content and fossil carbon content, biochemical analysis, measuring content of cellulose, hemicellulose, and lignin, is used in MELMod, landfill gas generation model in UK. Methodologies to develop DOCF has several methods including batch test, lysimeter test and test cell. They had difference in scale and similarity to landfill, but it is hard to consider the best method at the present stage. Preceding research on MCF is little. Lysimeter test and test cell can be the candidate to develop MCF, because of flexibility on test condition to characterize the structure of landfill sites. F is defined as fraction of methane in landfill gas. But by carbon flow and mass balance, F should represent fraction of methane in biogas generated by anaerobic decomposition. In this definition, F can be derived by same methods to that of DOCF.

Recycling the bottom ash from MSWI (Municipal solid waste incinerators) ash is required to reduce the secondary pollution. We characterized the bottom ash and investigated the possibility of application for subsidiary ceramic raw materials. Major components of bottom ash are analyzed as CaO, Al2O3, SiO2, P2O5, MgO, Fe2O3, which are the same components of the earth’s crust. This similarity of components implied that bottom ash could be recycled as ceramic products through systematic treatment. Considering the plasticity and water absorption results, the ceramics, which are the mixture with 74 wt % bottom ash and 26 wt% Pink Kaolin, showed 1.39% water absorption after sintering 1150oC for 1h. This result indicated the possibility of recycling of bottom ash for subsidiary ceramic raw materials.

A food waste disposer is an electrically powered device installed under a kitchen sink. It is located between the sink’s drain and the trap which shreds food waste into tiny pieces so that they can go through plumbing. Use of this unit is convenient and hygienic for discharging food waste in kitchen. Nevertheless, this unit has been illegal until now in Korea because of both conflict with the government’s policy-resource recovery from food waste-and perceived threat to the city’s sewer system. An attempt was made recently to meet growing need to introduce this unit for advantage of using disposer and maintenance of sewer system, etc. So an attempt was made to introduce the food waste disposer system of ‘treatment type before discharging to sewer’, but it was inappropriate for conditions in Korean. In this study, we developed a suitable disposer system for Korea based on an innovative solid recovery technology. And continuous operating experiments were carried out to evaluate the performance of the system for 18 days. The amount of food waste fed into the system was equivalent to the daily amount of food waste made from 30 households living in apartment units, which was calculated to be 14.44 kg/day. After grinding, SS/TS of food waste was 60 percent and it was the maximum amount of solid that could be recovered using this system. In the system of solid collection type using screw press, more than 70 percent of suspended solids were recovered. And less than 20 percent of total soilds were discharged through wastewater and it satisfied the legal standard of Korea. This novel food waste disposer system will satisfy with both the government’s environmental policy and higher quality resource recovery from food waste in the facilities.

Over the past few decades, many scientists and environmental activists emphasized the importance of sustainable society and warned the global warming. As one of efforts to achieve the sustainable society and maintain no more of global warming, the RDF (Refuse Derived Fuel) production from domestic solid is taken into account seriously in Daejeon, Korea. Currently, the pay per throw system is active from 1995 and is quite stabilized. Recyclable wastes such as metal scraps, glass, papers, and fibers like clothes should be discarded separately and not be mixed with other types of waste being disposed of eventually. To assess the potential for the conversion of domestic solid waste into a heat source, i.e., RDF, the proximate analysis, the classification into 10 components, and the calculation of heat value based on the result of the elemental analysis were performed. Based on the preceding analysis, the domestic solid waste produced daily in Daejeon, Korea has a potential for conversion into an alternative energy source, RDF in technical aspect. Proper blending of combustibles, however, is necessary to enhance the heating value of RDF being produced and to be more viable in economic aspect.

With total four lysimeters, having a decreased reaction rate of municipal solid waste (MSW) through the 1st study, the effects of foodwaste leachate (FWL) injection on the degradation of MSW and FWL were estimated for 533days. Average methane potential of FWL injected in lysimeters investigated through the Biochemical Methane Potential (BMP)test was 368.2 mL-CH4/g-VS. The amounts of methane generated in lysimeters injected simultaneously with FWL and leachate were higher than that of FWL injected each lysimeter. The pH levels of leachate generated in each lysimeter maintained a range of 7.2 ~ 8.1. CODCr concentrations were 1,640 ~ 2,275 mg/L initially, and were rising to 4,640 ~ 5,950 mg/L as increasing FWL injection amount. Whereafter those repeated fluctuation in a range of 2,400 ~ 5,600 mg/ L as methane productions in each lysimeter increase. BOD5/CODCr ratios were kept below 0.1 during the test period. Settlement analysis results of MSW in each lysimeter indicated that the simultaneous injections with FWL and leachate in each lysimeter promoted the degradation of not only FWL itself, but MSW. This became clear when the methane balance in lysimeter under rich-organic condition is established.

The objective of this study was to assess the affects of various solid waste landfill methods on mass balance of carbon. Four lysimeters simulated a conventional landfill (Lys-A), a landfill recirculated only fresh leachate (Lys-B), and two landfills recirculated leachate after pretreating with ASBR (Lys-C and Lys-D) were operated over 1,600 days. Lys-D was recirculated two times of pretreated leachate volume than that of Lys-C. Mass balance of carbon was calculated considering leachate and biogas production for each lysimeter. Lys-C and Lys-D showed that there was an increase of about 3 times in total amount of COD recovered as methane than Lys-A. This results might be attributable to the activated methanogenic bacteria and the high pH of pretreated leachate. In terms of mass balance of carbon, amount of carbon converted to landfill gas in Lys-B (25.20 g/kg-dry waste) was bigger than that of Lys-A (23.64 g/kg-dry waste), while carbon conversion rate to landfill gas for Lys-A and Lys-B showed 4.80% and 4.71%, respectively. It is assumed that only fresh leachate recirculation method can increase amount of carbon converted to landfill gas resulting from the biodegradation of organic carbon in recirculated leachate. However, in comparison with the conventional landfill method, this method should not accelerate hydrolysis of carbon from the wastes. Carbon conversion rate in the landfill recirculated leachate after pretreating with ASBR was increased due to accelerated anaerobic metabolism processes of the microbes. In Lys-C and Lys-D, about 5.9% of carbon was converted to landfill gas. Therefore, it could be seen that the landfill recirculated leachate after pretreating with ASBR could enhance carbon conversion to landfill gas more than the conventional landfill or the landfill recirculated only fresh leachate.