To investigate the biodegradation of lignin with high molecular weight (HMW) in sulfate reducing conditions, changes in the HMW lignin concentration and chemical structure were analyzed in the presence of a cellulose cosubstrate with a continuously-operated mesophilic reactor. Acid-precipitable polymeric lignin (APPL) and lignin monomers, which are known as degradation byproducts, were isolated and detected. The results showed that HMW lignin was degraded with a maximum degradation capacity of 3.49mg/L/day. APPL was confirmed to be a polymeric degradation byproduct and accumulated along with HMW lignin reduction. We also identified the nonlinear accumulation of aromatic lignin monomers such as hydrocinnamic acid. Through our experimental results, we observed that HMW lignin biodegrades into APPL and aromatic monomers in anaerobic sulfate reducing conditions with a cosubstrate of cellulose.

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This study discusses an autoclaved lightweight concrete (ALC) recycling system and the merits of this system. This recycling process includes carbonation reaction, sintering and autoclaving. In this recycling system, first ALC reacts with CO₂ because the main contents of ALC are tobermorite (Ca₅Si₆O₁₆(OH)₂-4H₂O) and α-quartz. Tobermorite can easily react with CO₂ and then produce CaCO₃ and silica gel. Sintering carbonated ALC between 650 to 800°C, belite (Ca₂SiO₄), one type of cement mineral, is produced. Then, autoclaving calcinated ALC at 750 to 800°C using an industrial process, tobermorite is reproduced. The merits of this recycling system include not only recycling ALC but also the reduction of carbon dioxide emissions. Using this recycling system, CO₂ emissions from ALC production can be reduced about 350kg-CO₂/ton according to calculations by a life cycle assessment (LCA) method.

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Municipal solid waste incinerators (MSWIs) are exposed to high temperature gases and acid gases that cause damage to the equipment within MSWIs. MSWIs need to be inspected and repaired at least once a year, a cost that has become a large financial burden on municipalities. Periodic repairs are normally contracted out to the companies that construct the MSWIs because the constructor is considered to be the only one who has the specific technical knowledge required for making repairs. This contract system makes it difficult to know what the exact repair costs actually are.
In this paper, current MSWI repair costing is investigated and a detailed inspection method for repair costing is then proposed. The paper also reports on several case studies that have been performed at some of the existing MSWIs. Results indicate that there are large differences among MSWI facilities when it comes to repair costs. It is necessary for administrative bodies at MSWI to adopt a reasonable detailed inspection method for estimating repair costs. In addition, when planning for the construction of a new MSWI, they must take into consideration not only the initial costs but also budgeting for periodic repair costs in the future.

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In long-term operation of a fluidized bed RDF combustion boiler, gas phase chlorine compounds are exhausted together with the other flue gas, and solid and liquid phase chlorine compounds with alkali compounds are circulated with bed particles, which are deposited to the heat exchanger tube, and can possibly cause the tube corrosion. The objective in this study is to clear the mechanism of the corrosion with alkali-chlorine compounds when the erosion results from collision of bed particles. The degree of corrosion was measured by the weight loss of a small sample of heat exchanger material, surface observation of the SEM/EDX, and the acid solubility. The results revealed that the tube corrosion is more likely to progress when weak erosion occurs in the ambient air conditions. Stainless steel like SUS310S is more preceded than nichrome. Thermodynamic equilibrium calculation results suggested that Ca₃Fe₂Si₃O₁₂ and CaCr₂O₄ are possible calcium components as a cause of heat exchanger tube corrosion.

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In order to confirm the performance of a seeding material for the treatment of organic waste, a laboratory scale treatment system was fabricated and the effects of activated sludge and the seeding material on the treatment of organic waste were compared. The ability of each system was evaluated by measuring chemical oxygen demand, pH, visibility, general bacteria, suspended solids and the amount of activated sludge. The ability of the seeding agent for the treatment of sewage water of skim milk and synthetic peptones was the same as that of activated sludge. In addition, in the case of the seeding agent, the amount of sludge generation was less than that with the activated sludge. The seeding material replenished the microbe groups in the sewage treatment tank and improved the efficiency of sewage treatment. It was confirmed that the seeding agent has sufficient potential to replace other methods such as activated sludge.

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The effect of temperature in practical use on moisture adsorption and desorption characteristics of waste wood charcoal was studied in order to increase the utilization of charcoal from waste wood as a humidity control material.
The mass changes of charcoal samples were measured by changing the humidity stepwise at 10, 23 and 30°C. The mass change of the charcoal corresponding to each change in humidity is considered to be the step response. The gain constant of the step response corresponds to adsorption and desorption moisture amounts, respectively. These gain constants for each charcoal sample are not widely different at each experimental temperature. The effect of temperature on the adsorption and desorption amounts is therefore small. Comparing the time constants of the step response for each charcoal sample, the time constants decreased as the temperature increased from 10 to 30°C. Adsorption and desorption rates increased as the temperature increased.

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The concentrations of the main and hazardous components of 26 sewage sludge ashes collected from 14 incineration facilities were determined in order to evaluate the practicality of making phosphate fertilizer from sewage sludge ash. Results indicated that sewage sludge ash is one practical source for making fused phosphate fertilizer. However, due to the high concentrations of hazardous components in the sewage sludge ashes, a fusing process for sewage sludge ashes was needed to remove the hazardous components from them.
Two sewage sludge ashes with appropriate amounts of additives (MgO and CaO) were subjected to fusing processes in an electric resistance furnace, and then crushed by immediate water-cooling. The fused phosphate fertilizer made from the two sewage sludge ashes had high solubilities of over 95% for P₂O₅ and MgO in citric acid. The mol ratios of P₂O₅, MgO, and CaO in the fused phosphate fertilizer were comparable to those of commercial fused phosphate fertilizers (P₂O₅:MgO:CaO=1:2.5-3.5:2.5-3.5). In addition, except for copper, the concentrations of hazardous components in the fused phosphate fertilizer were lower than that before the fusing processes and lower than the Japanese standard values.

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