An energy crisis can be the bottleneck in deterring sustainable economic growth. Nevertheless, most of countries have been suffering from useless energy and wasted materials. In this context, this paper is asking a question. What are the relationships among energy, economy and waste. Many new experiences on the Volume-based Garbage Collection Fee (VGCF) system in Korea and USA can give us meaningful information for understanding the ambiguous relationships among those things. Based on the comparative data analysis on the VGCF system in Korea and USA, this paper is trying to develop a GAGC (generally-acceptable-garbage- collection) method model from the renewing urban waste management point of view.

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The gradual rise of community-based recycling initiatives characterizes the kind of municipal solid waste management (MSW) strategy being put into practice in Metro Manila. In the midst of economic difficulties, recycling has become a stable source of livelihood for the unemployed and communities with low income. However, middle-income communities are doing the same as well, as a supplementary source of money to maintain local material recovery facilities. Regardless of social status, it is clear based on a study by the Asian Development Bank (ADB) in 2003, that recycling is being done across all sectors of society. Women are a force to reckon with in Philippine society. They are slowly integrating themselves in the government, private sector and in the area of MSW. A women organization in Metro Manila is slowly gaining distinction as a community-based organization doing plastic recycling and at the same time providing benefits to its members. The "Kababaihang Iisa and Layunin Umunlad and Sambayanan" or KILUS which means "Women with a Vision to Improve Society" has improved the lives of women in the community and heightened the awareness to recycle plastic in a simple and creative way. Cooperation and good leadership have made KILUS a success.

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Capacity planning of municipal solid waste (MSW) processing system, including the intermediate treatment and disposal facilities, is crucial in MSW management system, especially for the developing countries. Inappropriate intermediate treatment and disposal of MSW would lead to detrimental damage to the public health and natural environment. Moreover, the MSW emission rate in terms of the socioeconomic changes should be further considered in the capacity planning on MSW system. By using the estimation model system of MSW emission, established in the author's previous work, this study aims to conduct a short-term capacity forecasting of MSW processing system, up to 2011. Possible ranges of the available remaining capacity of MSW processing system are projected based on the assumed scenarios. Such capacity forecasting will provide necessary information for the policy decision-makers.

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Growing the concern about Global Warming, reduction of greenhouse gas (GHGs) emission has become a priority consideration in environmental field, especially waste management. Municipal waste takes a lot of carbons that can be converted to CO₂ and CH₄, representative GHGs. Therefore it is very important to investigate the carbon flow in municipal waste and quantifying carbon flow makes it possible to be more efficient waste management for reduction of GHGs. Material Flow Analysis (MFA) is one of the methodologies to investigate carbon flow and to support management of material flow. Also connecting the stock statistics for drawing the overall flow of municipal waste makes it possible to seek improvement matters for reliability of statistic data. In this paper, municipal waste in Seoul, Korea, was investigated and mainly classified as construction waste, domestic waste and industrial waste(except for hazardous waste). And then with each carbon concentration, carbon flow in Seoul was estimated As a result, the main carbon flow is along the domestic waste because of organic waste such as food, plastics and paper etc. One third of carbon in domestic waste flows to recycling process and similar amount to recycled carbon flows to incineration and landfill processes, respectively. This quantified carbon flow could be used to make out the GHGs generation through waste management by IPCC model.

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The amount of domestic generation of end-of-life electrical and electronic equipment (EEE), such as home appliances and personal computers (PCs), is increasing in most Asian countries. International trade of secondhand products, parts, and other materials related to EEE is also expanding. Since E-waste is potentially economically valuable but also includes hazardous materials, it needs to be reused and recycled in an appropriate manner. In order to clarify the international flow of secondhand home appliances, we estimated the export from Japan and investigated related regulation in East Asia.

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From the standpoints of environmental protection and nickel recycling, the development of an effective treatment method for spent electroless nickel plating baths is very important. We have been studying the recovery of nickel from the spent baths by continuous multistage solvent extraction and stripping process. High-extraction and stripping efficiencies of nickel using a mixer-settler were obtained. In this study, the continuous stripping data were quantitatively analyzed on the basis of the interfacial stripping rate equation considering the hydrodynamic properties in the mixer. The interfacial stripping rate constant of 7.3 x 10-10 m4/(s mol) was obtained. Finally, an engineering model was established for simulating the stripping efficiency of nickel during a multistage operation.

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A study on the behavior of reforming products from wood chip tar

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Food waste is the first cause that has 35% possession of all the household waste. Especially, the direct reclamation of food waste has been banned since 2005. This process effectively reduces the waste water from the food waste so that there will not be the second pollution and waste. Also, it produces from the food waste the thermal energy which is highly essential for the high concentration waste water originated from the food waste. In addition, it is installed on basement so that we can effectively use the ground space. What is more, it is environmental-friendly. It is not the hated facility any more. When food waste leachate was applied at the this process condition, the BOD removal efficiency of 99.9%, the COD removal efficiency of 99.9%, the T-N removal efficiency of 99.8%, the T-P removal efficiency 99.8% could be achieved. This process will be considered as the epoch-making method in that it has great advantages in intermediate product, product treatment and the machine's durability, compared to other method for food waste treatments such as making it compost and fodder.

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If source separation is not sufficiently conducted, construction and demolition waste becomes mixed state (called Mixed C&D waste) which is difficult to recycle. In Japan, 45% of mixed C&D was treated at treatment facility to recover recyclables and 37% of it becomes residue that has to be landfilled and has a high risk of H2S generation. Hence, removal of gypsum from residue is urgently requested. In this study it was investigated how gypsum is distributed to various outputs in sorting process and what density range contains the biggest concentration of gypsum. Following results were obtained: 1) Gypsum was distributed most (52.4%) to small fraction <8 mm size. 2) By heavy liquid separation conducted for fine fraction, it was found that 93% of gypsum was concentrated in the density range between 1.59 and 2.28 where 24% of total mass was contained. Hence, in order to reduce the amount of gypsum headed for landfill, removal of this density range after segregating fine particles will be effective.

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An evaluation of sludge dewatering by dual polymer conditioning of sewage sludge was investigated in this study.In the current study, both cationic and non-ionic polyelectrolytes were utilized in the conditioning. Also, Sludge conditioning by single and dual polyelectrolytes was evaluated, and digested sewage sludge in Seoul Metropolitan used in the experiment

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The characteristic of flue gas is estimated in experiments of thermal stabilization of sewage sludge cake. Thermal stabilized temperature is changed from 400°C to 700°C. Flue gas is measured at three points which are after temp-controller, water tank and bioreactor. Concentration of CO₂ in flue gas is increased from 0.5% at 400°C to 1.4% at 700°C. As increased stabilized temperature, stabilization is improved. Stabilized time is decreased as thermal temperature is increased. Concentration of NH₃ is increased from 114 ppm at 400°C to 128 ppm at 700°C. And concentration is dramatically decreased from 128 ppm after temp-controller to 35 ppm after water tank. Since threshold concentration of NH₃ is 53 ppm, odor of NH₃ is not occurred after water tank.

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An effect of aluminum content on characteristics of ceramic support is examined to obtain a high performance of ceramic support manufactured with the mixture of spent foundry sand/sewage sludge. Characteristics of ceramic support with aluminum content are estimated by bulk density, porosity, chemical resistance, and compressive strength. Forming of ceramic support is made with a compressed mold in this experiment. Sewage sludge is used after drying by oven. As the aluminum content is increased, characteristics of ceramic support are improved. Since porosity in ceramic support is decreased when aluminum content is more than 3wt%, aluminum content can be decided by 3wt%.

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No appropriate answer to sewage sludge that has been generating increasingly is a serious problem recently. Carbonization technology that produces carbonization residue (char) and useful substances is one of the treatment methods of sewage sludge, and the carbonization residue generated could be substituted for covering soil and expected to reduce the leaching of hydrophobic organic pollutants (HOPs) like PAHs and dioxins from landfill sites. To investigate the adsorption characteristics of carbonization residue to HOPs in the presence of dissolved humic matter (DHM), batch and continuous experiments are designed. In batch experiment, the adsorption characteristics are evaluated depending on contact time, pH of liquid, and DHM concentration. In especial, the change of functional group on carbonization residue would be determined. From the continuous experiment, adsorption characteristics of carbonization residue would be also investigated and the effect of DHM on the leaching of HOPs would be evaluated. As a result, this study could suggest the effectiveness of carbonization residue as covering soil in landfill sites.

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The objective of this study is to evaluate the leaching reduction of heavy metals in leachate using carbonization residue of sewage sludge as a covering soil in landfill. From the results of batch experiment applying the Freundlich adsorption isotherms, the well-carbonized residue showed higher adsorption capacity than the partly-carbonized residue and covering soil. In continuous experiment to investigate the effect of the well-carbonization residue of sewage sludge on improvement of water quality and leaching reduction of heavy metals, 4-type columns (column1: waste only (incineration residue + sewage sludge) ; column2: waste + cover soil ; column3: waste + carbonization residue ; column4: waste + carbonization residue + cover soil) are prepared, monitored and compared the results each other. From the result of TOC, the leachate from column3 was in the lowest concentration; and/thus the accumulated concentration of heavy metals in leachate from column3 was lower than the other columns. As a result, it could be expected that using carbonization residue of sewage sludge as a covering soil would have a good effect on improvement of water quality

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This study an attempt to assess the sludge solubilization by lactic acid bacteria considered good for health of human and animal.Aerobic microorganism in sludge was lysed in anaerobic condition and the cytoplasmic substance eluted was utilized as carbon source by lactic acid bacteria. And so, lactic acid bacteria was propagated and brought about the greatest solubilization enhancement. From the results of sludge solubilization efficiency, Lactobacillus brevis and Leuconostoc mesenteroides subsp mesenteroides were selected the best from five kinds of Lactobacillus sp.The solubilization efficiency of heterotype lactic acid bacteria is more efficient than that of homotype bacteria. Initial value of sCOD was 1050mg/L at the initial inoculation time increased to 3070mg/L (192% solubilization) at 96 hr of the incubation time.According to Leuconostoc mesenteroides subsp mesenteroides, 152% of solubilization over the same condition. It was found that 10% inoculation of Leuconostoc sp. to the sludge had most effective when we considered the effect of inoculation on the solubilization.

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The slag from steel manufacturing can be recycled as useful resources as an aggregate as well as soil conditioning. The leachate, however, has high pH and it area of application can be limited due to high pH leachate. In this study leaching characteristics of slag was evaluated and leachate was neutralized using carbon dioxide.The carbon dioxide can be applied to neutralize the slag leachate. The amount of carbon dioxide needed to drop the unit pH was varied with leachate pH level. The higher leachate pH was, the more carbon dioxide was consumed to drop the unit pH of leachate.The amount of carbon dioxide adsorbed by slag leachate was also varied with the leachate pH. At high high pH 90% of the carbon dioxide was adsorbed to slag leachate, whereas only 40% of carbon dioxide was adsorbed at leachate pH was around 9.It can be concluded that carbon dioxide can be utilized to neutralize slag leachate, and slag can be useful media to adsorbed carbon dioxide.

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A simple in-situ technique to enhance digester offgas methane content was developed by using the differential solubility of biogas at the mesophilic temperature. The methane enhancement systems were low solid plug flow sorghum digester coupled with a recycle loop to an external stripper. Quantitative evaluation of system variables defined the effects of leachate recycle rate(LRR) and reactor alkalinity on the resulting offgas methane contents and the total volatile solids(TVS) removal efficiency. The results show that offgas methane contents over 94% were observed at the reactor alkalinity of 4 g/L as CaCO₃ and at the LRR of 3 volume of leachate recycle per volume of reactor per day(3 v/v-d). The total volatile solids removal efficiency appeared 79% which was 94% of the control reactor. Offgas methane contents correlated well with the leachate recycle rates. However excessively high LRR led to digester pH levels above 8.8, resulting in inhibition of methanogenesis and lowered biogas production.

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Gasification process is one of the several technologies for converting wastes into energy resources and reducing the volume of solid wastes to be landfills.Gasification involves a partial combustion of solid waste (Refuse Plastic Fuel and Coal) to generate a combustion fuel gas mixture consisting of H₂, CH₄ and CO gas by using Refuse Plastic Fuel and Coal. The RPF obtained from municipal solid waste (MSW) material is an organic material for further processing. The RPF used consisted of approximately 60% plastic and some other waste material with moisture.Gasification of RPF and coal was carried out at 700°C with water (5 ml/min) and carrier gas (Argon) at a flow rate of 0.5 L/min. Amount of steam, reaction temperature and mixing ratio of RPF and Coal (Bitumous coal and Authcite) were considered as variable parameters for this experiment.In this study, experimental conditions were optimized to maximize the production of hydrogen gas from gasification process conducted on a lab-scale reactor. Gas chromatography. was used for analysis of gas mixture.

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This study was conducted to assess the recovery rate of anaerobic reactor under the overloading conditions. Anaerobic digester was operated from 30 to 60 days HRT in low temperature. Influent mixing livestock wastewater and food wastes in the ratio of 5:1 was used. In case of double and triple overloading rate, after overloading was kept for two days reactors were operated with original HRTs. And in quadruple overloading rate, after overloading was kept for a day recovery was observed. In the event of double overloading, TCOD and SCOD concentration were not shown big difference with normal conditions, but gas and methane productions were definitely decreased. All of the cases, the methane contents ware came back to 60% within a week, the pastest recovery was shown in the HRT 40 days. And total gas and methane production were risen to original conditions within 10 days.

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For the economically feasible production of ethanol, saccharified food wastes (SFW) by cellulases and amylases was used in the ethanol production of strain Saccharomyces italicus KJ. When SFW were used as the production medium, ethanol production yield was 0.56 g-ethanol/g-reducing sugar at batch culture. The synchronous saccharification and fermentation (SSF) process was revealed to be the most cost-effective process among previous reported processes. In this study, the most suitable condition of SSF was 2.0 U/mL of final enzyme concentration (amylase standard), 35°C of temperature and fed-batch culture method, in which 64 g/L of ethanol and yield of 0.45 g-ethanol/g-reducing sugar were obtained in 120 hrs culture by supplying food wastes with 12 hrs interval.

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Due to industrial development and diversification of life, the needs of resource utilization has increased and consequently the development and utilization of such resource is rapidly increasing as well. Due to the wastes generated every year and diversification of types of the waste, the counter measures for disposing such waste became a serious problem in the society. In Korea, reclamation and incineration are still occupying the most of the major disposing system and their economic feasibility and efficiency are poor. As for living waste policy in Korea, volume-rate garbage disposal system, EPR and etc are implemented but there is no significant effect. Also, due to the insufficient infrastructure for the recycling system, recycling and reducing the waste are difficult to be attained. In order to solve these problems, it is necessary to introduce mechanical biological treatment. The mechanical biological treatment refers to the sorting by applying mechanical treatment and implementing biological treatment for generating energy and recycling the products generated in the process with various methods. It is to reduce to final disposing amount and reclaim the left overs, which is the resource-cycle type waste disposal system. The mechanical biological treatment not only corresponds to the resource-cycle policy but it also enables to collect the energy through the treatment. Therefore, it is expected that this treatment will be operated and expanded in domestic and overseas countries and the related technology will be actively developed. In this study, the effects of food waste content in MBT system on aerobic stabilization response have been analyzed and examined.

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The effect of operating parameters on hydrothermal liquefaction of rice hulls was studied within 200-300C at pressure of 5-25 MPa. Very trivial amount of gaseous products (mainly CO2) were detected. Carbon content in lignin-free solid residue was accounted to be 4.5-9.1 %, while the rest of carbon was liquefied. Five sugars which are beneficial for SCWG process were detected as the main components in the liquid products, with cellobiose as the highest portion. Temperature increase did not show clear correlation to carbon content in solid residue, while the increase of pressure gave smaller carbon residue amounts (i.e., larger extent of liquefaction). Finally, two-step liquefaction experiment gave an increase of TOC amount in liquid product compared with single-step liquefaction at 220C.

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A plant design study for the thermal disposal and energy utilization of non-degradable liquid waste has been conducted by Institute for Advance Engineering(IAE) since 2005 in Korea. The pilot System mainly consists of gasification/melting reactor part for the high temperature degradation of liquid waste and combustor part for the syngas from gasifier . In this study we will present the result of the Combustor design by using CFD.

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Experimental Investigation on Gaseous Product Characteristics of Sewage Sludge Gasification

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A study on the recycling technique for jelly-filled copper cable

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To build Sound Material-Cycle society, we would like to reuse the residues from municipal solid waste incinerators (MSWIs) as raw material in cement industry. Because of the serious limitation for chlorine content in cement, we have to pre-treat fly ash to remove chlorides out. Normally washing experiment is adopted. In this paper, we use the method of combining X-ray absorption near edge structure (XANES) with X-ray Diffraction (XRD) to analyzed the chloride speciation in the washed residues of two kinds of fly ashes resulting from different neutralization reagent: calcium hydroxide and sodium bicarbonate, which were named as CaFA and NaFA respectively. We found that insoluble chlorides in both fly ashes are strongly connected to calcium chloride, which will be released under some conditions. After double washing, more total chlorine, insoluble chlorine, and calcium hydoxide are retained in CaFA. The efficiency of chlorine reduction is much greater in NaFA than in CaFA. So we conclude that NaHCO3 is superior to Ca(OH)2 as a neutralization reagent for reducing acid compounds in gas discharged from MSWIs.

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Recently by-products, such as industrial/municipal solid wastes and dredged waste materials, are increasing every year due to the development of industry and the increase of population. Thus, the treatment of the by-products has become a social problem in Korea. The final treatment of the by-products has been mainly performed by dumping these waste materials in landfill sites,but a shortage of the liner materials has some problems of the management in landfill because of the seasonal heavy rainfall and a scarcity of appropriate sites the a landfill. The amount of bottom ash in a coal-fired power is increasing every year and its physical properties are similar to the high quality clays so that the bottom ash might be compacted into a dense mass with a low hydraulic conductivity. Consequently, this study describes the development of a new impermeable liner materials, which was performed by changing mixing ratio between bentonite mixture and bottom ash.

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The purpose of this study is to investigate for compressive strength with different Admixture types on Solidification/Stabilization of fly ash from sewage sludge incinerator.

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Inorganic binder was made from MSWI bottom ash and blast furnace slag by geopolymer technique in this study. AS for manufacturing of inorganic binder, different MSWI bottom ash content and type of activators are investigated to obtain the optimum condition. The specimens were solidified under alkali condition and cured at 50°C. Compressive strength was measured to evaluate the characteristics of specimens for the period of 1, 3, and 7 days. XRF and XRD was also analyzed to find geopolymer matrix. The microstructure of inorganic binder prepared was analyzed by FTIR. As immobilization of heavy metals, the leaching test are employed to investigate the immobilization of the inorganic binder. TCLP method is used to environmental safety of inorganic binder.

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N-landfill, Hokkaido, Japan, had a problem of insufficient leachate collection and drainage system, accordingly leachate was accumulated in landfill. Remedial works such as installation of leachate collection pipe and gas well were conducted to promote stabilization of solid wastes. In this study, to evaluate the condition of the landfill body, leachate quality and a height of water column (WL) in gas wells were determined, and horizontal flow rate of leachate through gas well were estimated by tracer test. Among 93 gas wells, 48 wells were concerned for TOC and TN in leachate, of which 18 wells were estimated for WL and water flow. WL widely varied among gas wells, and it was mainly depended on original ground level and the depth of a well. Leachate velocity also showed a wide variation. Estimate of leachate quantity over the cross-section of the landfill well matched with actual discharge into leachate treatment plant. TOC decreased rapidly in summer in most of gas wells, and it was due to aerobic biological degradation in unsaturated waste layer around the wells. However, constant TOC in collected leachate suggests that decrease of TOC occurred only in the vicinity of wells.

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Landfill gas (LFG) consists of 50 - 60 vol. % methane, 30 - 40 vol. % carbon dioxide and trace amounts of numerous chemical compounds. Pressure and concentration of LFG as well as temperature gradients that develop within the landfill by biodegradation result in gas emissions to the atmosphere and in lateral migration through the surrounding soils. The amount of LFG emissions is depended on annual rates of waste generation, composition of the solid waste, landfill structure and burial practice, climate, microbiological methane oxidation, as well as methane recovery and utilization. The objective of this study is to investigate the seasonal variation of landfill methane emission in Thailand.

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This paper reports the current situation in the landfill sites in Ho Chi Minh City (HCMC), Vietnam. Main landfill sites in HCMC are Dong Thanh, Go Cat, Tam Tan (or Phuoc Hiep), and Da Phuoc landfills. There are also some small open dump sites in Thanh An (Can Gio district). Leachate quality in the rainy season and the dry season in Dong Thanh landfill and Go Cat land fill were shown. The problems in these landfills in present and future are discussed in this study.

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MTBE has been commonly used as an octane enhancer to replace tetraethyl lead in gasoline, because MTBE effects the efficiency of combustion and decrease the emission of carbon dioxide. However, MTBE has been found the fuel spills in groundwater and leaks in the UST(underground storage tank). This study investigated the optimized conditions of modified fenton oxidation(MFO) of MTBE using wasted zero-valent iron(ZVI) with wasted steel scrap as the source of catalytic ferrous iron. In this study, it was examined to find the optimal molar ratio of MTBE : H2O2 on extent to degradation of MTBE in groundwater at pH=7 with wasted ZVI=10%. As a results, the optimized ratio of MTBE to hydrogen peroxide for MFO was determined to be 1:300(in mM). Also, MTBE was removed 50% of initial concentration. The residual products were acetone, TBF and TBA during this test. The authors can surmise that recycled materials can be effectively used as the source of catalytic ferrous iron in fenton oxidative system to remove of MTBE in groundwater.

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We recently developed a composite adsorbent of lanthanum and zeolite for water remediation, specifically, controlling a lake eutrophication. Since phosphate is a well known nutrient responsible for algae bloom, internal phosphate control both in water and sediment column was considered to enable to water remediation. The hypothesis of this study was made that the fabricated adsorbent binds phosphate to settle, and prevent the resuspension of phosphate from sediment. Substantially, phosphate efflux into the water column is reduced. For this purpose, a composite adsorbent composed of lanthanum as substituted ion and zeolite as embodiment material. In the adsorbent, lanthanum is easily reacted with phosphate to produce a precipitate without any dismantlement from the mother body, zeolite works for embodying ions, particularly Lanthanum (La³⁺). In our previous study, it was observed that the fabricated adsorbent proved its effectiveness of phosphate control as well as ammonia nitrogen control. In this study, a column test was performed to further evaluate its efficiency of algae control by mimicking a lake system including water and sediment column. Detailed observation will be presented in the conference.

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Fly ash is an important industrial by-product, in terms of its production quantity and its influence on environment by heavy metals. But geopolymer possess excellent mechanical properties, fire resistance and chemical resistance; and geopolymer technology can also be employed for waste disposal in that it can immobilize toxic metals. We investigate which factor for a three alkaline activators influences physicochemical of inorganic binder. The alkaline activators that have been used for activating fly ash include NaOH, KOH and water-glass (sodium silicate solution). Compressive strength was measured to evaluate the characteristics of specimens for the period of 1, 3 and 7 days. And the morphology was analyzed by XRD. The microstructure of inorganic binder prepared was analyzed by FTIR. Korea Standard leaching Test (KSLT) and Toxicity Characteristic Leaching Procedure (TCLP) method are used to and examine leaching potential of inorganic binder.

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This research used the Batch Test to experiment the adsorption abilities of carbonized,which occurred during the carbonization process used as a method of recycling food wastes, to heavy metals.

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Fine ferrous wastes have been widely generated from the mechanical process in the steel industry and elsewhere. In terms of the strategy on the prevention and recycle of waste, the generated fine ferrous waste can be an acceptable alternative adsorbent. This study evaluated the feasibility of fine ferrous waste as the adsorbent for phosphate removal from wastewater. In the analysis of XRD, the used fine ferrous waste had the inverse spinel structure, mainly composed of Fe₃O₄; FeO Fe₂O₃=(Fe²⁺)(O^2-)(Fe³⁺)₂(O^2-)₃). The adsorption characteristic was analyzed by the well-known adsorption theory, i.e., Freundlich adsorption isotherm. This theory well corresponded to the experimental observation. It was also found that the adsorption capacity of the waste for phosphate strongly depended on the alkalinity of the sample water. This study will give the potential benefit of promoting closed substance cycle waste management and ensuring environmentally compatible waste disposal.

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Discharged PCDDs/DFs with flue gas from incinerators were easy to absorb on particles such as dust, and then diffused surround environment by the wind or rain. This study estimated of the influence on environment of discharged PCDDs/DFs from incinerators using to multivariate analysis by 2,3,7,8-substituted PCDDs/DFs.2,3,7,8-substituted PCDDs/DFs pattern in flue gas and ambient was divided according to 4 groups. Group 1 had PCDDs/DFs of flue gas and ambient (3:1), and group 2 was only flue gas, group 3 was flue gas and ambient (2:3), group 4 was only ambient. The distribution ratio of PCDFs and PCDDs according to respective group was group 1 to 61:39 and group 2 to 66:34, group 3 to 77:23, group 4 to 97:3.

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This study was estimated the emission characteristics and emission factors (EF) of the discharged PCDDs/DFs by flue gas from the waste incinerators in Korea. PCDDs/DFs concentration from selected incinerators (n=173) was 0.0 ∼ 204 ng/Sm³ (avg. 15 ng/Sm³) in large size incinerators (n=80) and 0.2 ∼ 319 ng/Sm³ (avg. 18 ng/Sm³) in medium size incinerators (n=93). And the distribution ratio of PCDDs and PCDFs was about 70 to 30. PCDDs/DFs concentration according to waste was 0 ∼ 10 ng/Sm³ (avg. 3 ng/Sm³) in MSW incinerators (n=26), 3 ∼ 319 ng/Sm³ (avg. 84 ng/Sm³) in hospital waste incinerators and 0 ∼ 204 ng/Sm³ (avg. 17 ng/Sm³) in industrial waste incinerators.

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In general, various substances in solid phase samples (e.g. water,carbons etc.)could hinder the determination of PCDDs/DFs.To control the moisture in samples, EPA and JIS adopt the method of airing or using of anhydrous sodium sulfate,however,these methods would be time-consuming and suspicious in effectiveness.Thus,in this study,solvents of acetone and toluene successively would be used in soxhlet/dean-stock soxhlet extraction of solid-phase samples containing moisture, and the results are compared to the other results described above. While,most of incineration plants for municipal solid wastes are using the activated carbons to control PCDDs/DFs in flue gas.It is well known that PCDDs/DFs adsorbed in/on activated carbons or unburned carbons in ash are very difficult to be extracted by soxhlet extraction method. This study would also evaluate the effect of activated carbons on extraction efficiency and suggest the proper extraction solvents for activated carbons-containing samples.

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An Enriched consortium obtained from the lake sediment was developed for the removal of heavy meals such as copper, lead, chromium, nickel, and zinc from heavy metal-contaminated lake.To find the optimum growth and metal removal condition of the isolated strain LH2, effects of the environmental factors such as medium pH, growth temperature, and metal concentrations were investigated. Based on the 18S rDNA analysis, the isolated strain was identified to Exophiala sp. LH2 with 100% homology. Isolated strain Exophiala sp. LH2 showed maximum removal efficiency of metals at the shaking conditions of pH 7 and 25°C. When 200 ppm of each metal was contained in the culture medium adjusted with pH 7, metal removal efficiencies of Cu, Pb, Cr, Ni, and Zn were 99.28%, 97.67%, 91.94%, 99.77%, 99.61% respectively.

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