Pyrolysis and combustion experiments of dried sewage sludge were conducted using an electrically heated drop furnace to elucidate NOx formation/destruction characteristics. When the dried sewage sludge was fed into the drop furnace, the particle temperature rose rapidly and the particles swelled. The char particle structure became balloon-like. Regarding NOx formation, both NO and N₂O were formed during combustion. After N₂O was generated in the flame, NO was produced because N₂O was destroyed by H radicals formed by CO oxidation. Although conversion of fuel-N into N₂O decreased with increased furnace temperature, conversion of fuel-N into NO increased. The N₂O conversion ratio of the dried sewage sludge was higher than that of the sample coal because the dried sewage sludge emits more HCN, which more readily produces N₂O.

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Waste molding sand discharged from the casting process was treated and reformed using high-temperature and high-pressure water. The surface of the waste molding sand was stained with 1.2wt% of carbon and 0.065wt% of nitrogen. Carbon and nitrogen that were removed from the surface by high-temperature and high-pressure water reaction at 300°C, 8.6MPa were 30wt% and 64wt%, respectively. Under the same conditions, with H₂O₂ as an oxidizer, these removal rates were both 64wt%. In the reaction at 450°C, 40MPa, these removal rates were similar to those at 300°C, 8.6MPa. However, in the reaction at 450°C, 40MPa with an oxidizer, these removal rates were 88wt% and 100wt%, respectively. The acidity value had doubled because of the reaction with high-temperature and high-pressure water on the sand surface. However, it did not increase when the oxidizer was used in the reaction.

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PCBs are harmful substances. Thus, the completion of their treatment inside Japan is mandated by 2016. The purpose of this research was to formulate the reaction rate of detoxification of PCBs using the combination of microwaves and catalysts through the calculation of the rate constants in two cases: high PCB concentrations and low PCB concentrations. The rate constants for high PCB concentrations and low PCB concentrations are calculated by using the assumption that under microwave irradiation, the PCB decomposition reaction rate using catalysts is proportional to the first order of PCB concentration. Although, the sizes of lab scale and pilot scale reactors are different, the consistency of experimental data and calculation results from each experimental condition are comparatively good. Therefore, it is possible now to determine the appropriate operation conditions and reactor designs suitable for the amounts of PCBs that must be decomposed.

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To develop environmentally-benign pretreatment systems applicable to recalcitrant softwood, we studied combined pretreatments for Japanese cedar wood with white rot fungi and microwave organosolvolysis using ethanol, glycerol and propylene glycol. A white rot fungus, Phellinus sp. SKM2102, increased yields of the reducing sugars obtained by enzymatic saccharification by more than 5 times at maximum. Among the safe solvent systems producible from biomass, solvolysis with ethanol and lactic acid was the most effective for the pretreatments.

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Although it is believed that large amounts of floating marine debris are carried through rivers, there have been very few investigations done to back this up. This paper reports on the influence typhoons have on beach litter. The report is based on investigations that were conducting using periodic monitoring of major items found on the sandy beaches of Tottori, which is contiguous to the Sea of Japan and was hit by 8 typhoons in 2004. Beach litter was found to be 1.7 times more than that of 2008 when no typhoon affected the area. While typhoons increase the amount of Japanese litter and litter where the origin is not identified, there appeared to be a decrease in the litter coming from China. This is due to the strong northerly winds from the East China Sea. Summer typhoons are accompanied by southerly winds and high waves that increase the amount of litter coming from local inland sources to the beaches near the mouths of rivers. The high waves also wash up litter that had been buried onto the beaches far from outfalls. The autumn typhoons are accompanied by northerly winds and heavy rains that cause the litter to spread from outfalls to distant beaches. This paper goes on to discuss the various means by which litter can be transported by waves, as well as wind and surface outflow from rivers and the distribution of inland litter.

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