This paper describes methods to make effective use of scrapped Fiber Reinforced Plastics (FRP) for admixture of mortar and concrete. The mixing method and the flexural property of discontinuous fiber reinforced mortar were investigated using glass fiber which was reproduced to reclaim and decompose the scrapped FRP with the aerial pulverizer.
From this experiment it was found that the flexural strength and toughness of mortar were improved with an increase in fiber content. Furthermore, it is possible to restrain the decrease of mortar strength with the ages by an alkali deterioration for glass fiber by replacing 30 to 50% of cement with blast-furnace slag.

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It is very important to know the dominant forms of heavy metals in fly ash generated from municipal solid waste incinerators or ash melting plants for consideration of detoxification and recycling. In this study, zinc, lead and copper in fly ash sampled in twenty municipal solid waste incinerators and five ash melting plants were analyzed using X-ray photoelectron spectroscopy. The dominant zinc compounds were 2ZnCO₃⋅3Zn (OH) ₂on the surface of fly ash and Zn or ZnO within the fly ash. PbCO₃and/or PbCl₂on the surface of fly ash were estimated. The chemical forms of copper did not depend on the fly ash type or depth and CuCl₂was not detected. Zinc and lead are therefore predominantly concentrated on the surface of fly ash.

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To clarify the effects of combustion-and composition-related parameters on the promotion and prevention of the formation of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in municipal solid waste incineration, multiple regression analysis has been carried out by analyzing the experimental data obtained at the laboratory-scale fluidized-bed combustion reactor. The laboratory-scale fluidized-bed combustion reactor, to which artificial refuse derived fuel is fed, is designed to simulate the combustion process in a municipal solid waste incinerator. The artificial refuse derived fuels used are made of pulverized materials, which are typical of municipal solid wastes. The result of multiple regression analysis shows that volatility, Cu contents in the RDF, and HCl, CO concentrations, promote the generation of PCDDs and PCDFs in the flue gas.

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Composting is one of the most popular waste treatment and recycling methods. However it is impossible to judge the possibility of composting of a new material without conducting any experiment. It is also theoretically difficult to find optimum operational conditions for composting.
In order to solve these difficulties, simulation is considered as one of useful methods. In this paper, simulation of composting reaction was attempted by consolidating experimental data which attempted to clarify the effects of operational and environmental conditions on composting kinetics. Validity and limitation of simulation was discussed by comparing its result with experimental results. How to collect important data pertaining to conditions to simulate composting is also discussed Information concerning composting material necessary to conduct simulation and how to in conclusion, it was shown that simulation of composting reaction is a useful tool in understanding composting reactions.

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The measured values of a CO₂analyzer by infrared absorption and an O₂analyzer by magnetic wind were compared at a municipal waste incinerator. Then, the methods for estimation of CO₂level emitted from the municipal waste incinerator with the continuous O₂analyzer were investigated.
The mean sum of CO₂and O₂concentrations measured by the analyzers was 20.1% and was similar to the literature data by the Orsat type analytical method. The estimated CO₂ concentrations by eq. (1) corresponded with the measured values by the CO₂analyzer. The amounts of CO₂emitted from the municipal waste incinerator estimated by eq. (5) from the O₂concentration corresponded with the calculated values from the mean carbon content and the incinerated amount of municipal waste. It was confirmed that the concentration and the emitted amount of CO₂could be precisely obtained from measured values by the O₂analyzer.

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