Two types of biomass adsorbents were prepared for the removal of Cs(I) and Sr(II) from water.  First one was prepared from biomasses containing high contents of polyphenol compounds such as tea leaves and persimmon tannin as well as from waste microalgae after extracting biofuel for the purpose of removing Cs(I). Second one was prepared from orange juice residue rich in pectin substance for removing Sr(II). Due to their high selectivity and high adsorption capacity, they can be expected as effective and low-cost adsorbents for these radioactive elements existing in trace concentrations in water.

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"Solidified condition" and "Un-solidified condition" were made by using same bottom ash and their leaching characteristics of heavy metals were examined by column leaching test. It was confirmed that although ash that contains CaO or Ca(OH)₂ tends to solidify, repetition of wetting and drying made the ash not solidify. Two kinds of ash were made to solidified and un-solidified state respectively. And they were subjected to the column leaching test in which the ashes were exposed to atmosphere or CO₂. Cumulative leaching amount of Ca under CO₂ condition increased because CaCO₃ was thought to be dissolved by pH drop. This indicated that severe exposure to CO₂ tends to increase leaching amount of metals. Regarding Pb, cumulative leaching amount increased in solidified condition although it was restrained in un-solidified condition. These results are thought to be caused by inhibition of carbonation due to decrease of permeability and hydraulic conductivity. Cumulative emission of heavy metals from bottom ash that tends to solidify increases since high pH value is maintained. But bottom ash subjected to the repeating procedure of wetting and drying becomes not to solidify and leaching of heavy metals from it significantly decreased.

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It is necessary to control the leaching of toxic metals in municipal solid waste incineration (MSWI) fly ash before landfill disposal because MSWI fly ash contains higher concentration of some toxic metals. However, the impact of morphological surface conversions by chelating treatment of MSWI fly ash on the immobility of metal is still uncertain. Therefore, this study investigated morphological surface characteristics and their conversions of MSWI fly ash. SEM observation showed that MSWI fly ash was mineralogically active. Although the incorporation of metal into needle-like crystals was observed, its contribution to metal immobilization is likely limited. After fly ash particles were grouped according to their morphological characteristics, their surface elemental compositions were analyzed. The results showed large heterogeneity and μm-level site dependency even in the same group samples.

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According to emerging concerns of mercury toxicity and international efforts to reduce mercury applications, the recovery and long-term safe disposal of unused mercury is requested. This study focuses on a scenario that mercury was landfilled as HgS, leached to outer environment, and thus reached to human exposure. Mercury environmental fate model was built to evaluate environmental risk of mercury disposal in landfill sites. Parameter sensitivity analysis was conducted to find significant parameters for simulation results. This analysis suggested that percolation flow rate in a landfill site, representative length of semi-closed water area (lake or sea), distribution constant of methylmercury, methylation/demethylation rate coefficient in the sediment, bio-magnification factor of methylmercury were effective. Therefore, this study concluded that it is necessary and effective to verify site-specific values of these parameters for reliable environmental risk assessment of mercury disposal.

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Recycling and refining of waste lubricating oils generated from the industries, automobiles and other manufacturing units are gaining lot of interest in Korea and around the world mainly because of the resource depletion of petroleum refinery and environmental concerns upon disposal and treatment. In case of developed nations, waste lubricant oil is considered as a source of energy and therefore converted into either high-grade fuel or low-grade fuel or base oil, and refined oil. Although incineration of high grade fuel and low grade fuel is commonly practiced in countries such as US and Europe, conversion of waste lubricant oil to re-refined oil as a resource recovery requires large amounts of subsides and  incentives by government. In Korea, waste lubricating oil was included in the extended producer responsibility (EPR) in 2003 to better manage and recycling of the oil. In 2012, Korea produced 1,425,598 ㎘ and sold 991,207 ㎘ of lubricating oil. In this study, actual recycling rate of waste lubricant oil is calculated based on waste oil entering into a waste oil recycling facility; this waste oil usually includes waste gas, sludge and moisture content. Therefore, the aim of the paper is to determine the actual recycling rate of waste lubricating oil by using material flow analysis (MFA). According to the study, a total of 10 site visits to waste oil recycling facilities with a survey containing 34 questions were made around the countries. The material flow of inputs and outputs, and byproducts through recycling and refining processes of waste lubricating oil in the recycling facility was carefully studied. Based on the results, most of waste lubricating oil at the recycling facilities was treated either by chemical treatment, vacuum distillation and high temperature pyrolysis. It was found that the actual recycling rates were approximately 93.4%(add standard deviation) for chemical treatment method, 81.4%(add standard deviation) for vacuum distillation method, and 80.6%(add standard deviation) for high temperature pyrolysis. More recycling processes and stages for the vacuum distillation and high temperature pyrolysis are required to high-grade fuel oil, which resulted in lower actual recycling rates at the facilities. 

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Global increase in the demand for the new Electrical and Electronic Equipment (EEE) lead to the rapid increase of waste electrical and electronic equipment (WEEE). Significant efforts on developing divers WEEE technologies are being made by many developed nations. This study focuses on developing a road map using quality function deployment (QFD) and analytic hierarchy process (AHP) for better managing and recycling of WEEE in Korea. In order to develop a roadmap on WEEE recycling technologies, a total of nine experts developed 22 different research projects of WEEE recycling. A detailed evaluation of the proposed projects was made by using AHP method with a number of experts and professionals. Evaluation of reliability and validity of the data obtained were conducted, along with SPSS statistical software. By using the QFD technique, a survey regarding potential problems, suggestions, and difficulties at several WEEE recycling facilities were conducted and evaluated. Evaluation of the proposed projects was made by the criteria, which was developed by expert meeting. The evaluation criteria were classified into upper and lower levels. AHP weights reflect the results of the final QFD analysis. In this study, proposed research projects (No 3, 5, and 10) showed higher importance index, and are related to plastic sorting technology and recovery technology of rare metals in WEEE. The proposed WEEE recycling technology roadmap emphasizes the development of effective size reduction of large household appliances and advanced screening techniques (e.g., plastics) in short period of time. In the long term period of time, the roadmap includes the development of better recovery technologies for rare metals and valuable materials during refinery process of WEEE.

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Food waste is one of the major fractions in municipal solid waste stream in Korea. In 2010, Daejeon Metropolitan City (DMC) with a population of 1.5 million generated 492 ton/day of food waste, which accounted for 32% of the total MSW generated in DMC. Recycling of food waste is commonly practiced in Korea, especially after the ban of dumping of food waste into landfills in 2005. In 2010, DMC recycled 82% of its food waste. Major food waste recycling methods in DMC are composting and fodder manufacturing (wet feed manufacturing and dry feed manufacturing). However, there are many management problems associated with the method, including operational problems, and the quality of the composting materials and feed products. The best sustainable food waste management methodology is still unknown in DMC; the purpose of the study was to compare current management system with the assumed food waste management systems from an environmental standpoint using life cycle assessment(LCA) as a decision making tool. In this study, the total emissions of pollutants were evaluated for 1 ton of food waste to be managed. The study discusses potential environmental impacts of the collection, transportation, recycling process and final disposal of food waste in DMC, and suggests better management options of the waste in DMC. 

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To make a sustainable waste management plan, Taiwan government surveyed the quality and quantity of municipal solid waste in different counties of Taiwan. It is believed that human activities can influence the generation of municipal solid waste (Chen, 2003). In order to figure out the reasons that resulting in the different pattern in waste quality, this study tried to propose a series of analytical procedures including Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) to indicate the roles of socio-economic conditions in waste generation. The results can help and provide evidence and advice for the government to develop policies of waste management. 

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Management of
solid waste is a serious issue for the fast growing metropolis of Dhaka.  As the demand of recyclable products is
increasing day by day in order to save resource and energy, informal waste
pickers/scavengers play an important role in the waste recycling process of
Dhaka.  Waste recovery and recycling are
carried out by underprivileged people and that’s why social and health issues
are now considered as the integral part of the solid waste management for
developing a sustainable society.  The
study helps us to identify the current amount of municipal waste generation and
their effects on the environment, collection of inorganic waste by the
scavengers, how the recycling chain formed at the city and environmental and
socio-economic problems related with recycling and recovery processes.

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The waste hierarchy refers to the "3Rs" reduce, reuse and recycle, which classify waste management strategies according to their desirability in terms of waste minimization. Finally non-usable wastes go to the landfill. In developed countries, landfilled waste amount has been decreased and the importance of prevention, material recycling has been growing.
However, realistic priority for supporting waste management in developing countries has shown in reverse. In many countries in Southeast Asia, technical improvement of landfill is the most urgent issue. Besides, increasing waste amount in developing countries is also main problem because the usable capacity for landfill is limited by the public resistance and environmental contamination. For reducing the disposed waste amount, there are two concepts of material recycling and energy recovery. As growing energy supply issue in Southeast Asia, this study is aimed to explore the item to solve both energy supply and reduction of waste amount by waste-to-energy technologies.
It has been reported that deforestation problem by indiscriminate logging for cooking fuel or energy source in industrial part. In this study, we will discuss appropriate technologies for achievement of energy supply and global warming problem based on our site visiting in Cambodia.

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The purpose of this study is create a material flow chart through the filed survey and statistical data. derived recycling system problems from it, and then suggest improvement plan in recycling.

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Waste generation in the Philippines has accelerated at a fast pace due to rapid economic and population growth and has contributed to environmental degradation.  The objective of this paper is to review the current municipal Solid Waste Management (SWM) and its challenges in the country, and discuss the possible and innovative ways to manage solid waste issues.  The 3R’s integrated waste management method is the main type of SWM in the country.  Despite the passage of RA 9003 law in 2001, only about 21% and 4% of the Local Government Units (LGUs) in the country are being serviced by municipal recovery facilities and sanitary landfills, respectively.  Moreover, while the LGU of Los Banos was able to successfully address the problem of solid waste through community mobilization and political will of its highest official, SWM in the country could still be considered as not effective or efficient.  Therefore, in order to have an effective SWM in the Philippines, the LGUs should have the political will to innovatively comply with RA 9003, through mobilization of all sectors concerned towards minimizing solid waste and uplifting the economic status of the vulnerable groups involved on SWM.

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Indium is one of the rare metals and 84% of it is mostly used as transparent electrodes of indium tin oxide (ITO) films of flat panel displays in 2007.  With recent trend of large sized flat panel displays and expanded market share of them, demand for indium has increased significantly and recycling should account for appropriate portion of indium supply.  On the other hand, significant portion of ITO etching waste solution is being discarded.  Therefore, appropriate portion of ITO etching waste solution has to be recycled to recover indium to comply with EU’s WEEE (Waste Electrical and Electronic Equipment) and RoHS
(Restriction of Hazardous Substances) directives.  In the present research, copper and tin were selectively removed by cementation with cobalt powders from indium-bearing etching waste solution.  The cobalt ions
were enriched by subsequent electro-winning process²⁾, where aluminum and indium ions were electrolytically reduced on Ir-coated Ti cathode.

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Plastics are the most important materials used in a number of applications. Since the plastic has been synthesized commercially, the production, consumption and generation of plastic waste is still growing. Appropriate plastic waste treatments are very essential for both economically and environmentally. Because plastic material has a very high calorific value, it could play a roll as a alternative energy source instead of fossil fuels. As a necessary consequence, however, the combustion of plastic waste emits several hazardous air pollutants (HAPs). Therefore, the composition of plastic waste might be fundamental and preliminary information for evaluating their economic values, environmental impacts, and human health risks. LA-ICP-MS has been widely investigated as a powerful analytical technique for the direct analysis of solid matrix samples. The advantages are fast in-situ analysis, low sample consumption, and lack of polyatomic interference species. Moreover, LA does not require complicated sample-preparation procedures, so the risk of contamination or sample loss can be avoided. In this study, polyethylene (PE) materials were analyzed by LA-ICP-MS. We describe using the LA-ICP-MS equipment to explore the most optimal conditions for in-situ quantitative trace element analysis of plastic waste. The BCR-680 was used for the analytical QA/QC.

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In this work, MSWI ash and melting slag were used to prepare exterior panel. We discuss affecting factors to the flexural strength of exterior panel. The highest flexural strength was obtained at K(2). It is in the range of the standard flexural strength of extrusion concrete panel (KS F 4735).

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Several basic factors of qualification and assessment of environmental soundness such as flexural strength, compressible strength, absorption and leaching test were measured and analyzed to evaluate.

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Fly ash and bottom ash, the by-products from industrial combustion process were investigated as an alternative material to increase the alkalinity.

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Tele-communication cables of the waterproof type are widely used in internet service, high-speed internet access and voice and video services. As often in the case of non-waterproof cables, atactic polypropylene
flooding compound is applied between their protective sheaths about the cable core to prevent water entry. Recently the manufacture of traditional copper multipair cables is in decline due to the newly installed fibre optic technology. 6500 tons of jelly cable waste was evolved in 2008. Jelly cable wastes should be properly handled for environment-friendly recycling and one of the fundamental recycling process is to separate the copper and plastic fractions from jelly filled cables and to produce clean copper granules free from jelly, which is the main topic of the present study.

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Lighting is classified into filament lamps and discharge lamps, depending on lighting method. More then 80% of the households or industries use fluorescent lighting. Using energy-efficient fluorescent light bulbs saves money and help protect the environment. Fluorescent bulbs consist of all shapes and sizes : ompact fluorescents, fluorescent tubes, and high-intensity discharge bulbs used for exterior lighting. Since fluorescent bulbs and tubes contain mercury, they must be properly treated in environmentally-benign way for recycling according to EU’s WEEE and RoHS directives. Virtually every component of a fluorescent lamp can be recycled, including metal end caps, lamp glass, and mercury phosphor powder. The recycled glass can be used as feedstock in the manufacture of glass products, or as cement aggregate. The aluminum end caps are recycled as metal scrap. Mercury recovered from the mercury phosphor powder by retort process and subsequently purified could be reused in thermometers, barometers, and electronic devices.

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 The electroless nickel plating is one of the important plating technologies, and high concentration of its large amount of waste solution is generated with nickel, phosphate, hypophosphite and various organic acids [1]. Electroless plating process is simple and it does not use external electric current to produce deposit. Therefore electroless nickel plating is applied to many electronics industries due to possible the uniform layer formed onto different geometry and the possibility to control the thickness [2]. Electroless nickel plating reactions are as follows [3]:
 With time, nickel and phosphate ions are simultaneously reduced to form the coating and the spent plating solution is discarded to maintain plating quality. However this wastewater is a valuable source of Ni with other hazardous organic compound and phosphate. Currently, the spent baths are treated by alkaline precipitation, but this process generated a large amount of hazardous sludge [4]. In this study, the purpose of electroless nickel plating wastewater treatment was performed to effectively remove the harmful species (COD, P, N) and recover Ni metal. For Ni recovery, selective precipitation and electro-winning process were utilized and the organic species were removed by advanced oxidation process.

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The problem of livestock excretion disposal is issuing recently because of collectivization and scale-up of the livestock industry. Livestock wastewater is a kind of high-concentrated organic wastewater, so it is treated by anaerobic digestion process because treating by aerobic has a lot of restrictions from technical aspect. Anaerobic process is possible to decompose the organic matters and this process generate end product a little. Futhermore, it can remove intestinal parasites and produces the bio-gas which contains methane. But Anaerobic process is difficult to operate because of low temperature in the field. Therefore, to operate anaerobic process in the field, autothermal aerobic digestion has to be applied to transfer a heat. The object of study is to research treatment efficiencies, the operation property and biogas productivity by the new-type reactor which is connected the anaerobic process and the autothermal aerobic process.

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In this study, we compared the predominant microorganism after confirming the hydrogen production surface using anaerobic biological degradation in response to the extra concentration of food waste. Showed a 1268.67ml of hydrogen gas production by the highest salinity wastewater was 3g/L, but the food waste salinity was 30g/L of hydrogen gas production lowest 130.73ml. It was able to know that the salinity is the inhibition of the hydrogen production and growth of microorganisms. Result of 16S rDNA PCR-DGGE, elucidated in microorganisms most crowded Clostridium sp. or Klebsiella sp. and microbial contribution of the hydrogen generator is large, Clostridium sp. It was judged.

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