Sorption of biodegradation end products of nonylphenol polyethoxylates onto activated sludge

Nonylphenol(NP), nonylphenoxy acetic acid(NP1EC), nonylphenol monoethoxy acetic acid(NP2EC), nonylphenol monoethoxylate(NP1EO) and nonylphenol diethoxylate(NP2EO) are biodegradation end products(BEPs) of nonionic surfactant nonylphenolpolyethoxylates (NPnEO). In this research, sorption of these compounds onto model activated sludge was characterized. Sorption equilibrium experiments showed that NP, NP1EO and NP2EO reached equilibrium in about 12 h, while equilibrium of NP1EC and NP2EC were reached earlier, in about 4 h. In sorption isotherm experiments, obtained equilibrium data at 28℃ fitted well to Freundlich sorption model for all investigated compounds. For NP1EC, in addition to Freundlich, equilibrium data also fitted well to Langmuir model. Linear sorption model was also tried, and equilibrium data of all NP, NP1EO, NP2EO and NP2EC except NP1EC fitted well to this model. Calculated Freundlich coefficient(K F) and linear sorption coefficient(K D) showed that sorption capacity of the investigated compounds were in order NP>NP2EO>NP1EO>NP1EC≈NP2EC. For NP, NP1EO and NP2EO, high values of calculated K F and K D indicated an easy uptake of these compounds from aqueous phase onto activated sludge. Whereas, NP1EC and NP2EC with low values of K F and K D absorbed weakly to activated sludge and tended to preferably remain in aqueous phase.

Optimal turning method of composting regarding hygienic safety

The new turning method was proposed and verified its effectiveness to pathogens by laboratory scale experiments. Considering the results obtained from the previous studies, it could be said that turning of a composting pile was essential in terms of hygienic aspects but the number of turning should be minimized. Effectiveness of inactivation was estimated for each composting run. From this estimation, turning by layers, which is different from conventional turning that mixes compost pile entirely, was proposed and investigated its performance by experiments. Composting operations with static pile method, complete mix(conventional) turning method, and proposed turning(layer turning) method were done and their effectiveness on inactivation of indicator microorganism was evaluated and compared. As results, the conventional turning method was not a proper method in terms of pathogen inactivation, whereas, the proposed turning method showed an excellent performance and should be employed in a composting operation.

Production of Safe Charcoal from Waste Construction Wood Treated With Citric Acid

For practical reuse of wastewater containing citric acid and the production of safe and healthy high-quality charcoal from waste construction wood, basic data regarding the influence of citric acid washing treatments on the physico- chemical property of charcoal was investigated in order to find the benefits of using citric acid for washing out impurities of the wood, owing to its chelate bonding ability with elements such as metals. Parameters obtained for evaluating the benefits were water content, volatile component content, ash content, fixed carbon content, and the heat value of the charcoal. All parameters, except ash content, throughout all carbonization temperatures were not significantly different between the charcoal of the wood treated with and without citric acid. However, the ash content showed significant differences between the charcoal treated with and without citric acid throughout all carbonization temperatures. Regarding the heat value, the highest heat value was shown on the charcoal carbonated at 600?C with the static washing treatment. Dioxins that were higher in content than the control sample were somehow detected in the ash of the charcoal with the shaking treatment. Further investigation is needed for the production of safe and healthy charcoal using waste citric acid.

Comparative evaluation of processes for heavy metal removal from municipal solid waste incineration fly ash

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Behavior of Cu, Pb, and Zn in Ash during the Endothermic Burning of Mixed Industrial Wastes

The behaviors of Cu, Pb, and Zn during the endothermic burning of heterogeneous wastes were investigated using a variety of operational parameters, i.e., the mixed waste ratio, burning temperature, and burning time, to obtain fundamental knowledge to generate an optimal burning operation and recycling strategy for bottom ash. Changing these parameters had no impact on the Cu content of the ash, whereas the Pb content depended on the burning temperature and the mixed ratio, and the Zn content was affected by all three parameters. It was found in this study that the optimal burning conditions were a temperature of 1100?C, a time of 15 minutes, and either the current waste conditions or waste conditions with double the waste plastic and wood content.

Total Recovery of Sinker Weights from Lead-Core Fishing Nets

The adverse effects of lead poisoning have long been of environmental concern. A large number of research papers have reported many routes of lead poisoning, of which lead sinkers used in fishing require urgent attention. Lead sinkers that are abandoned or scattered from individual fishing gear are notorious for environmental pollution and have been reported in many papers;moreover, lead-core “sinker rope” is used in fishery nets. This paper discusses the latter, which generally has limited public awareness. Preliminary work and field studies were conducted to develop a system for total treatment of lead from fishing nets with lead-cored sinker ropes, in order to prevent environmental pollution and conserve natural resources. Lead sinkers in fishing nets were successfully removed, yielding high-quality lead suitable for commercial purposes. Appropriate management of fishing nets is crucial for environmental protection and resource conservation.

An investigation on the nutrient and material effects of bark in komatsuna and tomato growing tests by using pots to determine the optimum mixed combination

The effects of bark on komatsuna (Japanese spinach) and tomato were investigated by changing the nitrogen content of chemical fertilizers and bark mixing ratio. Mixing 25 and 50% of bark with soil improved komatsuna growth, and also exceeded the growth rates obtained by using chemical fertilizers. However, komatsuna could not grow in 100% bark alone, with excessive amounts of bark majorly inhibiting komatsuna growth. The aeration of bark also did not enhance komatsuna growth. The nitrogen content and bark-mixing ratio had a much lower impact on tomato growth compared to komatsuna. In comparison, aerated bark was more effective in enhancing tomato growth compared to komatsuna growth.

Waste Research Trends in Japan in the Past Ten Years: Review of What We Had Done before the Catastrophic Events of March 2011

This study analyzes waste research of the past decade in order to determine Japanese trends as well as to learn the problems of Japanese research. The results show that waste research has focused mainly on treatment, management, and recycling, and that research on prior processes such as reduction, collection, and transportation has been very limited. It was also found that research placed stress mostly on materials rather than people and the trend was very similar to that of a ministry oriented research fund. It seems that Japanese waste research has been neither balanced nor strategic. We therefore conclude that a government direction on waste studies might be not appropriate. Japan and Japanese researchers must change their ways of thinking in order not to repeat these mistakes.

Case Study: Finding Better Solutions for Municipal Solid Waste Management in a Semi Local Authority in Sri Lanka

This case study investigates better and sustainable waste management for a given area in Sri Lanka. A questionnaire and field surveys were performed in a small local authority adjacent to Colombo, the capital city. Composting for organic waste and incineration for non-compostable waste were found to be important treatment methods for solid-waste management. The reduction of solid waste is a critical process for sustainable management. Currently, people in the area do not have much interest in waste recycling to decrease the cost of solid-waste management. It was therefore concluded that raising people’s awareness would play an important role in the reduction of solid waste. A suitable waste-management plan needs to be made for each community and area. The situation and conditions of every area is different, therefore each community needs to make an effort to find its own better and sustainable solid-waste management process.