Tsunami deposits by the 2011 off the Pacific coast of Tohoku Earthquake contain much organics due to herbaceous species and/or oceanic sediments caused fire in temporal dump. Therefore, it's important to know organic matter content more precisely and more simply on site. Then, we proposed and evaluated to improve the method of loss on ignition. In conventional procedures and conditions, value is overestimated. In this work, the experimental results mainly focused on burning behavior of wood-based biomass are discussed. In any experiments, variations of the sample weight with time are continuously measured under constant temperature. From experimental results, it was found that simply mixed lignin, which was not used as adhesive to bond cellulose fibers, discouraged pyrolysis and burning itself and promoted production of solid residue such as char. When effect of initial sample weight was investigated, the larger initial weight was, the longer time taken to burn out became. Using crucibles with different shapes, on the other hand, different weight loss behavior was indicated even though initial weight was equal. Comparing between with and without a cover of crucible, it was found that the supply of oxygen was largely obstructed even though there was a certain gap.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Total reflection X-ray fluorescence spectrometry (TXRF) was applied to analysis of toxic elements eluted from fly ash of municipal solid waste combined with the leaching test of No. 13 defined by Ministry of Environment in Japan. Internal standard method was used for toxic analysis in the waste water and eluate samples as quantification method, and its method can be applied to element analysis in water sample easily and rapidly because calibration curves for quantified elements are unneeded different with other analysis methods such as Atomic Absorption Spectrometry (AAS) and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). In analytical results of the eluate from fly ash, analytical value of Pb was shown higher than standard value of the leaching test of No. 13 although Cr, As and Cd were not detected. Lower limit of detections (LLDs) of all elements were lower than standard values of the leaching test of No. 13. Therefore, it is thought that TXRF can be applied to toxic element analysis of water samples.

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[in Japanese]

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Infectious wastes generated in clinics, medical facilities, research institutes and others are classified as specific hazardous wastes and requires specific collections and treatments. This paper reports present situation of infectious wastes management and some of accidents which might cause further infections. Because of high-temperature treatment for safe disinfection, flammable materials included in infectious waste containers are prohibited. Needle-stick accidents, in which pseudo-infectious needles are stuck out from containers, cause potentially further infections to works in charge of collection. Inappropriate packing cause container deformation, partial destruction, and incomplete covering. Although statistical data of accidents and inappropriate packing are important to improve collection system, it is very limited. Basic surveys are strongly required.

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The present study analyzed organohalogenated flame retardants (OHFRs) such as polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), 1,2-bis (2,4,6-tribromohenoxy) ethane (BTBPE), decabromodiphenyl ethane (DBDPE), and dechlorane plus (DPs) in dust and soil samples collected in and around a relatively modern electronic and electrical waste (e-waste) recycling facility in Bengaluru, India, to elucidate the work environment contamination by OHFRs. In addition, serum samples were collected from seven workers in the e-waste recycling facility and OHFRs were analyzed to assess the exposure levels. PBDEs, HBCDs, BTBPE, DBDPE, and DPs were detected in all the dust and soil samples analyzed, suggesting the release of these OHFRs into the work environment during e-waste recycling activities. On the other hand, OHFRs were not detected in all the serum samples from the workers and the similar phenomenon has been observed in our previous study conducted in 2013. These results indicate the diminished intake and absorption of OHFRs by working conditions improved since 2007, e.g., continuous wearing of masks and gloves and installation of higherformance draft.

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The initial stage of waste management flow chart is waste collection. Used tools for waste collecting are well-known as trash bins or trash containers. Although trash bins seem to relate to waste separation efficiency, only a few researches are concerned about the impact of trash bins on waste segregation. Trash bins are designed to encourage waste segregation of recyclable and non-recyclable wastes in public. Normally, there are four kinds of trash bins set for waste disposers; trash bins for combustible waste (burnable waste; BU), incombustible waste (NC), PET bottles (PE), and cans (CA). A previous study of the authors researched on psychological preferences of trash bins arrangement (Jiang et al. (2017) Proceedings of the 8^th China-Japan Joint Conference on material recycling and waste management, 206-209, Hangzhou, 16-20th Sep.). In this study, the authors would like to know the impact of four trash bin arrangement preferences, which was quantified by questionnaire surveys, on real waste segregation efficiency.

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In public places, generally, MSW can be separated into combustible waste, incombustible waste, PET bottle and CAN. In this study, authors have focused on trash bin color, since it might give non-negligible impacts on human behaviors on waste separation. Therefore, this study investigated color preferences of trash bins, in particular focusing on its structural correlation. In this research, web questionnaires data was used to scale the color preference by binary pairwise comparison method. 10 common different colors for trash bin were decided. In web questionnaires, questionees were requested to only answer the better color in each pair by imagination. The selection ratio dataset was analyzed to quantify the preference degree (Z value) using Thurston’s law of comparative judgment. Based on this, authors comparing the preference structure of the most preferable colors with other colors. Investigation of gender balance and age distribution has been conducted to the groups with low consistency. According to the web-questionnaires, the most preferred colors were red for combustible waste; gray for incombustible waste; white for PET bottle; gray for CANs, respectively. In general, colorful design is more preferable, elder people relatively preferred lighter colors relatively.

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In Japan, a signature summer event is fireworks displays. There is a fireworks show somewhere in Japan every weekend during July and August. Thousands people will join the events, at the same time, tons of waste will be produced. To collect the waste and keep event place sanitary, temporary trash bins should be set to collect the waste. In order to maximize effectiveness of trash containers, management of the temporary trash containers is very important.In the other hand, even the Japanese people are already acquainted with the waste separation and resource recycle rules, their behavior can be changed when loose supervision. Therefore, the managementof trash containersshould consider events situationand human behavior. In this study, different trash containers will be discussed.

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Appropriate designs of rubbish bins could inspire the public for separate garbage collection in efficient way. Because of that reason, we need to understand people’s psychological preference on each bin for each types of waste such as paper, recyclable cans, polyethylene terephthalate (PET) or plastic bottles, and others. Even if waste and bins are really close to our daily life, there have been few dedicated design projects about appropriate trash bin design globally. When it comes to industrial design, there are several important things to consider. Arguably, one of the most integral factors is users. This is because design should be preferred by users. However, in the future, many researchers expect, large part of our population will be the elderly. According to the United Nations, “Globally, population aged 60 or over is growing faster than all young age groups.”. Thus, we need to consider our new design research focused on average physical ability of the elder people for better waste collection and management. Universal Design could be one of solution to tackle people’s physical difficulties. In this paper, we investigated potential universal design with principles and design concepts.

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PV technology is considered as a clean source of energy. However, considering its whole lifecycle, waste management may become a huge concern. The current level of waste PV panel generations are very small due to its long lifespan, but after 25-30 years, PV panel may be one of the dominant waste to be managed. Waste generation estimation is the essential information to design the appropriate management system for any waste. The objective of this study was to estimate the future regional waste PV panel generations in China. Considering China’s huge land mass and socio-economic differences among the regions, regional estimates would be useful. The regional level was set to province in this research.The estimation was carried out in three steps: investigating the installation of PV panels, converting the installation (GW) to weight (ton), and estimating the scenarios for waste stream.From the result of Jiangsu province, it was found that: a) the difference of waste generation due to scenario settings is small before 2020, b) the maximum waste stream is roughly five times more than the minimum waste stream, c) the waste stream may decrease after 2040s.

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There are various types of packaging materials including glass, plastic, wood, paper and cardboard, and metal. In recent time, plastic packaging is of global concern due to their single use, increased extraction of fossil resources for production, low recovery for recycling, persistence in the environment and marine pollution. Globally, various 2R (reduce and reuse), command and control, voluntary, educational and economic instruments have been applied to manage plastic packaging. These strategies introduce voluntary and involuntary usage of alternate carrier options such as reusable or eco-friendly bags (also known as eco-bags/my bags). The objective of this study is to grasp the behavior of usage and stock of my bags in Japan. Various factors including usage of plastic bags, age, gender etc. were considered. Based on a web-based questionnaire in mid-march 2018 where 2,900 consumers responded, the results show that the most owned and used bags are reusable plastic based material bags and cotton bags. Eco bag ownership and usage increased with age. However, females owned and used more reusable bags than males. To reduce the environmental burden of eco-bags, the frequency of usage should be improved.

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Kyoto city as a popular travel destination has attracted over 6 million foreign visitors in 2016 and this number is predicted to be continuously increasing (Industrial Affairs and Tourism Bureau of Kyoto City, 2016). The tourism industry has a large impact on Kyoto city in many ways with waste management being no exception. To grasp current behavior and consciousness of foreign tourists to inform further development of waste management schemes in Kyoto, this research adopted a questionnaire survey method to investigate tourism waste prevention situation. 126 questionnaires were distributed face to face to foreign travelers from 19 countries and districts in Kyoto at Kinkakuji Temple, Fushimiinari Shrine on 13th and 14th June 2018. As a result, the current tourism waste prevention schemes proposed by Kyoto city is less effective, while the propositions in Shimatsu no Kokoro Guidebook in tourism sector are practiced at various extends. Engagement of accommodations, retailers and other stakeholders requires further improvement for a more efficient tourism waste management in Kyoto. Moreover, the volumes of PET bottle and plastic bags waste generated in Kyoto is larger than that generated in tourists’ home countries. Thus, efforts can be further targeted to reduce waste generated by foreign tourists.

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According to Polluters Pay Principle (PPP), households are polluter which means that they are required to pay recycle fee. Therefore, before implementing e-waste recycle fee, there is a need to study willingness-to-pay (WTP) of households. The methodology for collecting data was interview of questionnaire by on-site suvery to 261 households. There were six district areas as location of study: North Jakarta, Central Jakarta, South Jakarta, West Jakarta, East Jakarta, and Seribu Island. The analysis of background of households and the intention to contribute in future e-waste management was conducted in the beginning in order to obtain basic conditions of households living in Jakarta. For analysis of WTP, it used doube double-bounded dichotomous choice contingent valuation method (DCCVM). Positively, 85% of households have intention to contribute in future e-waste management, especially e-waste collection and e-waste recycle fee. It means that it is potential to implement better and proper e-waste management in the future in Jakarta. Besides, about 59% of households have willingness-to-pay of e-waste recycle fee which means that there is potential to implement e-waste recycle fee in Jakarta, Indonesia. The capability of households in e-waste recycle fee is in good range of price for 4 types of house appliances (mobile phone, TV, refrigerator, and washing machine) which is 1% of their average income.

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Extended producer responsibility (EPR) has been an important concept in waste management for the last two decades, and approximately 400 EPR programs currently exist in the world (OECD, 2016). However, different perception of EPR tended to fuel policy disputes and confuse relevant arguments. We therefore surveyed stakeholders' perceptions of EPR worldwide and analyzed the results statistically to identify what kinds of stakeholders tended to have particular perceptions.

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People participation has direct effect in success of any solid waste management (SWM) plan. The main shortcomings in SWM of Kabul City are insufficient collection coverage, uncontrolled waste disposal at collection points and landfills, lack of proper waste treatment, poor management in the municipality, and poor cooperation among the populace. A study was conducted on community perceptions, expectations and their problems related to current solid waste management services in Kabul City. The people information and thoughts were collected through interviews and discussions. As a result, 75% of respondents are not satisfied with the current situation and only 48% dispose of their waste in communal bins. Low collection coverage and lack of communal bins were the people’s major concern. Income level and perceptions were identified as factors affecting willingness to pay. Results showed that only 14% are unwilling to pay and about 60% of the respondents are willing to pay 100 or more Afghanis, while about 50% of those respondents who are not currently paying are ready to pay at least 100 Afs. The study also reveals that higher collection frequencies have shown positive results with greater satisfaction.

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This study aims to exhibit an urban flood risk reduction strategy which solves urban drainage problems by managing solid debris derived from anthropogenic and natural activities, through administrative services on sewage and drainage clearing, waste collection, and citizen’s cooperation to waste disposal.

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Microplastics have in many colors and exist in many forms such as granules, fibers, fragments, films, and so on. In addition, microplastics have various materials such as PE (polyethylene), PP (polypropylene), PS (polystyrene), PVC (polyvinyl chloride), SBR (styrene butadiene rubber), and so on. Among these, SBR is a polymer mainly contained in tires. Some countries reported that SBR is the most emission of microplastics released to the environment. In this study, the microplastics existed in gutters were identified and the possibility of inflow to the sewage treatment facilities were confirmed.
The sampling sites selected were gutters located in the sides of pavement where the traffic of vehicles was seemed to be high in M city. Tire fragments accounted for more than about 60% of microplastics in the gutters. As a result of this study, it is considered that the microplastics existed on the sides of pavement flows into the sewerage by rainwater.

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Although informal recycling has been researched in many places and from many viewpoints, few studies examined how the recyclables reach a recycling factory, and how much recyclables become secondary materials, based on quantitative and qualitative research. For this study, Fieldwork was conducted 24 times within a total of 808 days between February 2010 to January 2018 with qualitative and quantitative interviews. The objectives of this work are to present (1) the estimated average weight of recyclables on an individual basis, (2) the estimated average weight of recyclables on a household basis, (3) the informal recycling rate, and (4) the estimated reduction effect of CO2 emission and energy consumption. The average amounts of recyclables were 84.5 kg for HW=0 and 66.3 kg for HW=1. The average amount of recyclables was 126.7 kg. The informal recycling rate was 2.2. It was estimated that 2.2% of all wastes and 12.3% of non-organic wastes were collected by waste pickers, that 1,384.5 tons/month of recycled materials were produced by the activity of on-site informal recyclers, and that every month at least 1,147.8 tons of CO2 and 76,015 GJ of energy consumption were reduced by the activity of on-site informal recyclers.

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As the economic growth and urbanization progresses, the amounts of Electrical and Electronic Equipment continue to grow in Sri Lanka. It impacts on consumer attitude and shorten the product life span.
Looking at the used home appliances called E-Waste, Majority of E-Waste are collected, dismantled and reused by informal sector, there are no national dataset available for their sales, generations, and actual condition of processing that may not be appropriate.
This survey intends to estimate E-Waste flow targeting 6 items (Mobile phone, PC, TV, Refrigerator, Air conditioner, Washing Machine) in Kurunegala Municipal Council which was selected as one of the pilot project sites in JICA Solid Waste Management project for "Expert in Pollution Control and Reduction of Environmental Burden in Solid Waste Management" conducting from February 2017 to develop their sorted recyclable waste distribution channel and E-Waste recycling approach appropriate to Sri Lanka.
The research found that the estimated result of E-Waste discharge amount in Kurunegala Municipal Council is 14,370 appliances/year (313.35 tons/year) (And 7.3 tons/year of E-Waste collected by the local authority). 60.7% of E-Waste is collected by repair/reuse shops, and 39.2% is collected by retailer/sales shops. The valuable parts are exported to more than 40 countries.

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We investigated not only increase of leaching of nickel but also recovery of lanthanum from mixed with 40 wt.% Alkaline batteries, 30 wt.% Li-ion batteries, 10 wt.% Ni-MH batteries, 10 wt.% Ni-Cd batteries accordingly generated amount of spent batteries in Korea. The leaching experiments were conducted with various factors such as kind of oxidation, ratio of solid and liquid, concentration of sulfuric acid, temperature. As a result, leaching efficiency of nickel was increased up to 98% with addition of 10 vol.% H₂O₂, while not only the nickel efficiency was increased Na₂S₂O₈ up to 94% but also the lanthanum was selectively precipitated as a La(SO₄)・2Na・H₂O by addition of Na₂S₂O₈. This process is benefit for simultaneous recovery of valuable metals and rare earth metals.

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In this study, we manufacture cobalt metal and electronic manganese dioxide from spent Li-ion batteries leaching solution which contains 21g/L cobalt, 0.46 g/L manganese, 2.5g/L nickel and 3.6g/L lithium. In first step, solvnet extraction process was applied to recover cobalt and manganese from nickel and lithium. In solvent extraction, the pure and concentrated cobalt and manganese were recovered by the experiments such as pH-isotherm, effect of saponification of 2-ethylhexyl phosphonic acid, McCabe-Thiele diagram, counter current simulation test. In second process, the electro chemical process was applied to simultaneously manufacture cobalt metal and electro manganese dioxide. The experiments were conducted such as effect of concentration of cobalt and manganese, effect current destiny, pH, effect of temperature. As result, the concentration of Mn is not affect the purity of cobalt metal which is over 99.8%. Also, for high current efficiency and low energy consumption of deposition of Co on cathode, the most important factors are pH and concentration of cobalt. Therefore, this study will contribute to recovery process of cobalt and manganese because of advantage for simultaneous recovery of Co and Mn at one energy consumption.

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A method combined of PVC swelling and centrifugal force was introduced for separating of Cu and plasticizers-imbedded PVC from thin electric cables. In the previous work, full separation and >70% extraction yield of plasticizer were achieved by stirring in acetone or ethyl acetate. In this work, mixed solvents of organic solvent and water replaced acetone or ethyl acetate to make PVC covering and Cu separated as well as keeping plasticizer imbedded in the PVC. DCM was selected as the suitable organic solvent by screening of organic solvents based on swelling rate, then, ratio optimization of organic solvent/water and feasibility of longer cable lengths were investigated. A maximum 97.5% R_sep and 4% Y_ext of 1 cm cable samples was achieved by stirring in 10 mL DCM/100 mL water.

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Phosphorus in water bodies can lead to serious eutrophication problem, such as rapid growth of algae and releasing algae toxin, which may break the ecological balance and even threat human health. However, phosphorus is also an essential nutrient and non-renewable resource for crop growth, but all the stored phosphorus resource will be consumed within 100 years. Therefore, designing a strategy for removing phosphorus from aqueous system and recycling use those phosphorus is imperative. We developed a novel adsorbent (Modified Si-Ca composite) which made of waste glass and shell composite to remove phosphate (P) from aqueous solution. Factors on phosphate adsorption including kinetic, isotherm and recovery were examined through batch experiments. Kinetic and isotherm adsorption results were well fitted with pseudo-second-order model and Langmuir model, respectively. The maximum phosphate adsorption amount calculated by Langmuir model was 61.7 mg/g. 95% phosphate from postsorption adsorbent could be recovered by 2% citric acid, indicating that the P-laden Modified Si-Ca composite has a good P bioavailability. Therefore, the Modified Si-Ca composite can not only remove a large amount of phosphate from wastewater but also apply the P-laden adsorbent directly to soil as a fertilizer for crop growth.

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The agglomeration and surface oxidation lead the application of nano zero valent iron (NZVI) to be difficult. Lots of works have been conducted on the utilization of supporting materials to enhance the dispersion of NZVI. However, the effect of supporting on oxidation of NZVI is not clear so far. In this study, supported NZVI on exhausted coffee ground were synthesized. Both the changes in surface characteristics and cadmium removal efficiencies of materials by aging were examined. The Fourier transformation infrared spectroscopy and X-ray photoelectron spectroscopy revealed that supported NZVI on coffee ground experienced less oxidation than bare NZVI. After the aging, there was no change in cadmium uptake by supported NZVI on coffee ground but that by bare NZVI significantly decreased. Our results showed that exhausted coffee ground is excellent stabilizing material to prevent oxidation and keep reactivity of NZVI.

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Waste glass is often recycled as a raw material for glass. Glass has a characteristic of being porous and light when it is foamed. In this study investigate the efficiency of CSOs filtration by waste glass filter. The filter media size was 2mm and 14mm. This filter media made of waste glass by high temperature molding. In small apparatus, SS removal efficiency was the highest when sand height was 200 mm. In large apparatus, SS removal efficiency was the highest when sand height was 150 mm.

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Starting from the ancient Greek sponge to the present synthetic sponge, the history of the sponge has been very long and has been widely used in a variety of fields from home to industrial. However, all of these sponges are disposed of as general garbage, and there are difficulties in recycling. In this study, we have modified the sponge of polyvinyl alcohol(PVA) with polyacrylic acid(PAA) and fixed the surface with Zerovalent Iron (ZVI), which can remove various kinds of pollutants through the oxidation/reduction, adsorption mechanism. In the case of ZVI, it will be made into nano-size to increase the surface area to improve the reactivity, and additionally, the double metal catalyst will be attached.

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The development of filtration technology for sewage reuse is increasing to solve the problem of water shortage due to the increase of water usage. In this study, two filters that coated with diatomite and celpure were compared their removal performance. In order to compare the removal efficiency, two items of SS and T-P were experimented. As a result, the removal efficiency of the filter coated with celpure was higher than removal efficiency of the filter coated with diatomite. However, despite the addition of coagulant, the removal efficiency of T-P was low in both filters. As a result, it was found that the sewage contained a lot of dissolved phosphorus. Therefore, it is considered that the technology for removal of dissolved phosphorus should be done in next studies.

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In this study, we applied an original simplified fugacity approach to figure out the phase partitioning behavior of PBDEs in biogas plants. The results indicated the fraction of organic portion in the liquid and solid phases had a variable influence on partitioning to the gaseous, liquid and solid phases. The high concentration of DOC in the liquid phase should be emphasized due to the great impact on the variation of gas partitioning of PBDEs. Both low-PBDEs and high-PBDEs prefer to partition into the liquid and solid phases. High-PBDEs with low value of log K_aw should be carefully considered in biogas plant in terms of emission to the environment.

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The odor-causing VOCs(Volatile organic compounds) were generated from the anaerobic digestion of the sewage treatment plant. These odorants should be removed by a suitable removal technology for preventing odor problems and upgrading the process of biogas. To properly control and manage odorous substances, it is necessary to know precisely the generation characteristics of odorous substances. This study was proposed to investigate the accuracy and stability of the multi-sorbent tube for VOCs sampling. The experiment has been designed to analyse the gaseous emissions from anaerobic digestion by using the thermal desorber connected to the gas chromatography mass spectrometry(TD-GC/MS), and examined the effectiveness of the multi tube compared to the single tube sampling method. For the analysis using the multi-sorbent tube, all targeted substances were detected, but for the single sorbent tube, two individual substances (i.e., n-Hexane and n-Tetradecane) were not detected by GC/MS. This demonstrates that the use of the multi-sorbent tube can effectively collect VOCs with various properties compared to the single sorbent tube. Response factors by the multi-sorbent tube were relatively higher than those by the single tube.

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This study investigated the influences of thermal hydrolysis pretreatment (THP) on mesophilic (37±1 ℃) and thermophilic (50±1 ℃) anaerobic digestion (AD) of swine manure. Anaerobic biodegradability and digestion performance were evaluated in lab-scale anaerobic reactors. The specific methane yield of THP-treated swine manure under mesophilic condition was more stable than that under thermophilic condition. The process instability and inhibited phenomena were more obvious in thermophilic reactors.

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Concerns about the release of veterinary antibiotics (VAs) thorough anaerobic digestion (AD) into environmental systems are greatly increasing with the gradual increase of VAs consumption. This study was aimed to investigate the dependence of anaerobic primary degradation and transformation of chlortetracycline (CTC), which is one of the most-consumed VAs, on its inhibition to AD. Primary degradation is defined as degradation of a parent compound into lower molecular weight products. Transformation means optical (ECTC) or structure (ICTC) isomerization of a parent compound. AD of cattle manure with CTC for 30 days was conducted using batch-wise anaerobic assays at 35oC. The assays in 10, 25, 50, 100 mg-CTC/L represented 100, 90, 80, 80% (v/v) of CH₄ generation compared to that of the control, and degradation of CTC were 42, 30, 25, 25% (w/w), respectively. However, the mass ratio of ECTC (or ICTC) did not depend on the inhibition and were 30 - 40% (w/w). Lowered performance of AD by CTC can cause increased environmental exposure of CTC. ECTC and ICTC should be considered as residual CTC because they maintain the chemical structure of CTC and possibly have similar antimicrobial effects that CTC has. Retransformation can happen after ECTC are released to the environment.

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Poor soil fertility is one of the main constraint on agricultural productivity in Cambodia. We investigated the effect of rice straw biochar at different application rates on growth and yield of Brassica Juncea. The crop was grown in a sandy soil (pH 5.5) of the open field in a randomized complete block design with four different rates of biochar (0, 0.5, 1, and 2 kg/ m²). The biochar was produced by the pyrolysis of the local rice straw for 4 h 42 min. The results showed that 1 and 2 kg/m² of biochar increased leaf mass by 49% and 126%, respectively, compared to control. Moreover, the number of leaves and leaf width were also significantly by 1 and 2 kg/m² of biochar separate but the leave heights were significantly affected by treatments. These results indicate that rice straw biochar could improve the growth and yield of Brassica Juncea under the sandy soil and climate condition of Cambodia.

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The sorption of NH₄-N by biochar samples derived from banana peels, wood chips, and rice husks at 300-500℃ was studied. There were significant differences in elemental composition and functional groups among these biochars. In the study, the adsorption of ammonium on the biochars were well fitted with the Langmuir model. The banana peel biochar had the largest sorption capacity for NH₄-N, with a maximum sorption of 19.2 mg g^-1. This ammonium sorption capacity can be explained by the biochar’s high polarity and its large number of oxygen-containing functional groups. The results illustrate that the biochar is expected to act as both an effective and low cost sorbent for ammonium ion removal from aqueous systems.

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this study is samplig the waste tire in the SRF production facility to carry out the ash and elemental analysis, investigated and based on this, cause exceeding the quality standard was analyzed.

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This work focuses on investigating the interactive influence of easily biodegradable organic content and air-flow rate on drying phenomena and water removal in bio-drying process.
The lab-scale experiments were carried out using the dog food representing the degradable organic contents ratios (10, 25, 50, 75, and 100) under 3 different air-flow rates (0.4, 0.7, and 1.1 L/kg-VS/min) provision. During the experiment, the temperature of simulated waste, temperature and relative humidity of inlet/outlet air was monitored. Exhausted gas was sampled periodically to calculate the organic degradation and followed metabolic water generation by analyzing the CO2 concentration. A simple model was established based on the experiment to see the drying phenomena.
As a result, high air-flow rate provides greater replacement effects and in case of high organic contents, the more water is removed as longer the period of high temperature is maintained. However, the fast decrease in moisture content would limit the microbial activity and terminate the biodegradation earlier

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Landfill management in Asian countries mostly go to final disposal site. Due to lack of Municipal Solid Waste (MSW) recycle and utilization, nearly 100% of MSW was end up with landfill. High waste generation rate makes landfill rapidly full. From MSW characteristics, a half of MSW in Asian countries consist of organic materials that show high potential of Greenhouse Gases (GHGs) generation. In the tropical region is clearly distinguished from dry period (winter and summer seasons). This climatic condition would affect to greenhouse gas emission during biological process. The study demonstrated the GHG mitigation potential of Biodrying MBT system. As compared to conventional landfill operation, MBT Biodry-I and Biodry-II significantly reduced GHG for 88% and 84%, respectively. The result indicated that the biodrying MBT show the important rule to mitigate environmental impact in terms of global warming. The dramatically decreased of MSW volume to final disposal site improves the problem of land use that happened in some area currently. Additional benefit from this technology is the utilization of MSW. The SRF business could be promote to local authority in Asian countries in terms of compensate from waste management activities.

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There is still requirement of efficient CO₂ mitigation technologies. Carbon capture and utilization (CCU) in which CO₂ was captured and reused as useful products is rising as promising CO₂ mitigation technology. In this study, we dealt with inorganic carbonation, one of the CCU technology. Inorganic carbonation in which metal cations in various materials react with captured CO₂ produces useful products such as MgCO₃. Ready Mixed Concrete (RMC) recycling water, one of the industrial waste, was selected as metal ion (Ca²⁺) source. We used liquid and solid forms obtained from RMC recycling water. Liquid form was supernatant (RMC-L) as solvent of amine absorbents instead of water through filtering RMC recycling water and solid form as solid matter (RMC-S) dried after filtering RMC recycling water.

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This study deals with the Carbon Capture and Utilization (CCU) technology using alkanolamine absorbents solutions and pretreated brine solution which is produced as wastewater in refined salt production facility. Alkanolamine solutions were saturated by 15 vol% CO₂-N₂ mixed gas which assumed to be industrial flue gas emitted from normal coal-fired power plant. Unlike direct carbon fixation method, all of the experiments were performed under normal temperature range (298.15 - 343.15 K) and ambient pressure (101.325 Pa). Ca²⁺ ions contained in pretreated brine solution is used as metal ion supplying source. 30 wt% of aqueous monoethanolamine (MEA), diethanolamine (DEA), and methyldiethanolamine (MDEA) solutions were used as absorbents, respectively, Also, calcium ions included in the wastewater was separated by using sodium sulfate producing calcium sulfate. After that, carbon dioxide was carbonated by the reaction between calcium sulfate. Though Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) analysis, precipitated salts were turned out to be calcite.

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In Kyoto, Japan on 11 December 1997, The Kyoto Protocol was adopted where leaders from various countries gathered to fight global warming by reducing greenhouse gas concentrations in the atmosphere to "a level that would prevent dangerous anthropogenic interference with the climate system". As they agreed to outline emissions targets such as CO₂, various methods such as CO₂ capture and storage were taken into considerations. Additionally, as a part of CCUS (Carbon Capture Utilization and Storage) technology, mineral carbonation technology (MCT) has caught attention in research as the “CO₂ is chemically reacted with calcium- and/or magnesium-containing minerals to form stable carbonate materials which do not incur any long-term liability or monitoring commitments”.
MCT can be categorized into direct and indirect carbonation as illustrated in the Table 1. Direct carbonation was used for this study as it can be approached more easily in contrast to the indirect carbonation. In addition, in case of advanced electric power generation technologies such as the integration of coal gasification with combined cycles (IGCC) or with molten carbonate fuel cells (IGMCFC), direct gas-solid reaction reflects more efficiency of CO₂ capture maintaining power generation. However, the disadvantage it holds is low carbonation rate and recycling the material.

MSW (Municipal Solid Waste) was utilized for mineral carbonation in this study. MSW thermal treatments generate fly ash and bottom ash. The latter is landfilled in South Korea after intermediate processing such as Solidification/Stabilization as it meets the allowable standard value of heavy metals although it has recyclable components. Also, the ash spawned could be exploited as an additive in cement or building materials. Therefore, we aim to perform mineral carbonation using MSW ash.
A comparative analysis of the efficiency of carbonation in context to the combustion method employing fluidized bed reactor and a fixed bed reactor was carried out. Furthermore, different experimental parameters were also examined to determine optimal experimental conditions for achieving maximum efficacy.

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Large amounts of CFBC fly ash are discharged from coal-power plant in Korea. And waste limestones(WL) are also dischaged. But these wastes are improperly managed and bring out the secodary contamination. Therefore, it is needed urgently to treat them safely. We studid the method to use them as geopolymer brick. In this study, we adopted CFBC fly ash and WL as raw materials. And also akali activator is used to leach and react Si and Al ions from them. Mixing ratio of CaO/SiO2, reacting temperature, L/S ratio and so on, are used as affecting factors. Compressive strength was over 30 MPa at 4.73 of CaO/SiO2. Acording to rhe results, CFBC fly ash can be used as raw material for preparing geopolymer brick. But It is needed to discuss alternative material and the preparation condition to enhance the recycling quality of them.

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Coal fly ash (FA) is one of the major by-products from coal-fired power generation. Global FA generation is estimated to be 800 million Mg/yr. Huge amounts of FA were disposed at open-air dumping site or landfilling without appropriate utilization. The storage and handling of FA are ongoing challenges in the context of environment impact. New applications of FA are significantly required. Research on recycling and reuse FA as eco-friendly products and engineering composites have been considered since the past decade. Functional polymers are promising candidates in fabrication of high performance composites as they are able to maximize the interaction between filler and polymer matrix. In this study, biodegradable polymer polyvinyl alcohol (PVA) was used as matrix; cellulose was used as the crosslinking holder to form supporting structures of fly ash based porous composites. Scanning Electron Microscope (SEM) observed the morphology of the composites, and the micrograph showed porosity of the composites varied with different temperatures in fabrication process. The objective of this research is to develop high strength biodegradable PVA/ cellulose/FA composites, thus recycle FA in fabrication of the composites with high FA concentration, which will be a potential candidate in application of industrial fields.

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Million tons of coal fly ash each year are generated after thermal energy production worldwide. Most of by-product fly ash after coal burning is disposed by landfilling. The management of this waste material becomes an environmental concern. In order to eliminate environmental problems and achieve economic benefits, recycling of fly ash waste into usable and valuable material is significant. Coal fly ash primarily contains alumino-silicate component which can be used as a source to form geopolymer synthesized by reacting with an alkali activator through geopolymerization reaction. Moreover, geopolymer has been used for many applications and also used as effective adsorbents for various heavy metals and organic compounds.

Geopolymerization induced to form aluminosilicate framework structures onto fly ash. The conventional geopolymer products have closed cell solid structure, low water permeability, and low porosity, limitting the adsorption ability. In term of removal applications of toxic compounds, a high porosity and large surface area of adsorbent material is very important. This study aims to report the obtained porous material which synthesized through geopolymerization of coal fly ash and effects of additional calcination treatment on the fly ash-based porous geopolymer.

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Introduction
Diapers are consumer products designed to absorb excretory fluid from the human body, such as urine and feces. In this research, five major types of adult diapers (tape, pull-on, flat, pad, and light incontinence pad) and two major types of baby diapers (tape and pull-on) were studied. The aim of the research was to analyze representative and reproducible compositions, to estimate fossil carbon fractions, and to quantify fossil CO₂ emissions for different types of diapers in Japan. The composition of a diaper depends on the manufacturing region, manufacturing year, and type of diaper, and affects the fossil carbon fractions and related emissions from diapers. Therefore, it is necessary to analyze the actual compositions of different diapers.
Methodology
The criteria for selecting samples were: brands with major market share, percentage of production weight and numbers, coverage of different functions, capacities, and gender. A total of 70 samples of 7 different types of diapers were analyzed in this study. Each sample was manually dismantled and weighed to determine the weight and percentage of its constituents. There are five different layers/materials in a diaper: surface layer, absorbing layer, leakage prevention layer, binder/tape material, and elastic/stretch material. From the information on the diaper labels and through Fourier-transform infrared spectroscopy, the following were identified as the constituents: polyolefin non-woven fabric (polypropylene) for the surface layer, cellulose pulp and superabsorbent polymers (SAP) for the absorbing layer, polyolefin (polyethylene) for the leakage prevention layer, polystyrene (PS) for the binder/tape material, and polyurethane for the elastic/stretch material. The carbon fraction (CF) of each diaper was calculated by multiplying the percentage of each constituent in the diaper with the carbon percentage of that constituent according to its molecular formula. The fossil carbon fraction (FCF) was calculated as the ratio of CF excluding biomass carbon from cellulose pulp to the total CF. The fossil carbon emission factor of diaper incineration (dry basis) was obtained by multiplying CF, FCF, oxidation factor, and 44/12 (total atomic weight of CO₂ divided by atomic number of a carbon atom). The fossil carbon emissions from different diapers were then calculated by multiplying the fossil carbon emission factor with the annual weight of incinerated diaper (ton), which in turn was based on annual production weight data for various diapers, obtained from the Ministry of Economy, Trade and Industry (METI, 2017).

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Industrial biomass is the byproduct of light-industry, such as spirit lees, herb residue, bagasse and so on. It is not only a kind of biomass resource, but also a serious environmental pollution source. Gasification is promising and attractive because of cleanness, high efficiency and large treating capacity. However, due to high content of moisture, nitrogen, and organic residue, the existing direct gasification process faces challenges, such as low efficiency, large temperature fluctuation and high tar content in fuel gas. So, innovating gasification process and reactor structure become essential and necessary. In this study, a new fluidized bed two-stage (FBTS) gasification process, mainly consisting of a fluidized bed (FB) pyrolyzer and a transport fluidized bed (TFB) gasifier, has been proposed by the Institute of Process Engineering, Chinese Academy of Sciences. This process decouples direct gasification process into two sub-processes, namely feedstock pyrolysis and char gasification. Depending on thermal cracking, partial oxidation and catalytic reforming by char, the produced tar will be removed to a very low level. To research and develop the FBTS gasification process successfully, the synergistic effect of thermal cracking, partial oxidation and catalytic reforming by char was examined systematically on a laboratory FBTS reaction apparatus.

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Traditional biomass in the form of firewood remains a major contributor to the total energy supply in Africa. Access to clean and sustainable energy is still low in most parts of Africa. This has negatively impacted the environment as deforestration, land degradation, desertification have been experienced at alarming levels against a backdrop of climate change. The promotion of green energy is needed to counteract the negative impact of greenhouse pollution. In this study, the potential of grape marc, a lignocellulosic solid waste stream from wine making, is accessed as feedstock for hydrothermal carbonization for the production of a carbon neutral fuel. Probabilty modelling is adopted in this study to overcome challenges in data reliabilty and uncertainty.

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