Observed data of NaCl transport experiments with unsaturated and steady water flow in medium sand, incinerator ash and artificial refuse layer were simulated by a dispersion model, ortwo-component model. Parameters of each model were obtained as functions of flow rate. The two-component model can simulate observed data in the ash and refuse layer. The dispersion model can also simulate observed data at a very low flow rate. According to this result and theoretical consideration, it is suggested that the two-component model should be a model for high flow rate for convenience.
Secondly, solute wash-out experiments by step-like or random pulse-like precipitations were done. The characteristics of solute wash-out in solid waste layers were also discussed. These observed curves were simulated by the dispersion model, or two-component model with the above obtained parameters. Consequently, the simulation almost succeeded for the sand layer and were less successful for the ash layer and refuse layer.

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Genotoxicity of fly ash samples from 23 plants and bottom ash samples from 10 plants were estimated by Ames mutagenicity after using the extraction method reported in the previous paper.
Mutagenicity was clearly observed in 8 fly ash samples, especially in TA98+S9 which shows mutagenicity of the frame shift type. Low level mutagenicity was detected in 3 bottom ash samples. Considering the information for the plants, high mutagenicity of the fly ash was estimated for the stoker type incinerator, which was operated in shorter residence time of gas. In the test at a stoker type incinerator operated in various feed volumes of waste and air flow rates, mutagenicity was increased with increases of CO concentration in flue gas and ignition loss of the fly ash. Namely, mutagens in the fly ash may be produced in incomplete incineration.
The mutagenicity of fly ash was lost after heating it at 400°C for 30 minutes, and some of the mutagens were decomposed by treatments with 2N HCl or 2N NaOH.

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Gas concentration profiles in landfill layers, behavior of organic and inorganic contents in leachate and self-purification capacity in the bottom landfill layers were investigated. Three large scale lysimeters simulating semi-aerobic landfill were used in this study. Lysimeter“A”has only one leachate drain pipe, and lysimeter“B”has a vertical gas venting facility and a leachate drain pipe. Lysimeter“C”has a largely air permeable layer consisting of 60-80mmφ converter slag in the middle of the landfill layer together with a leachate drain pipe and gas venting facility.
An area of more than 10% of oxygen concentration was enlarged by 2 times in“B”and 3 times in“C”, compared to lysimeter “A”. Simultaneously, it was observed that the decomposition of organic matters, e.g., TOC and T-N was accelerated, and a smaller amount of leachate was produced in lysimeter“C”, with higher air permeability. Behavior of inorganic contents, such as Fe, Mn, Ca, Cu, Zn, and Pb in landfill layers were found to have a tendency similar to those of the organic contents, which differ largely in concentration with depth. All heavy metals contained in the leachate were found not to exceed the effluent standards of Water Pollution Control Law. The leaching amounts of Mn, Ca, Cu, Zn, and Pb were also less than 1% of leachable amounts in the original adjusted solid waste over a period of 600 days after landfilling. Self-purification capacity in the bottom landfill layer was evaluated as BOD₅ of 0.23kg/m³⋅d.

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Hemicellulose has been extracted from peanut shells by alkali (24% KOH) treatment and ethanol (99.5%) precipitation. On TLC, its acid hydrolysis with 10% sulfuric acid at 100°C for 2 hr gave only one spot that corresponded to D-xylose with a yield of 45.5%. Also the hemicellulose was digested by crude xylanases from Aeromonas caviae ME-1 and Enterobacter agglomerans ME-2 producing mainly xylose, xylobiose and xylose, respectively.

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This paper describes an investigation of the water diffusivity of dairy cattle solid waste including cattle manure and the sawdust of Japanese cedar. The dairy cattle solid waste was dried at 40°C in an electric drying oven, then the dried matter was packed in an acrylic column to be used for measurements. The water diffusivity was measured by the horizontal infiltration method at 20°C atmosphere.
The result shows that the water diffusivity of the dairy cattle solid waste is from 10^-9 to 10^-7 m²⋅ s^-1. The water diffusivity is presented as a function of volumetric water ratio (water vol. / solid vol.) at the range of 9.2-13.8% of solid ratio.

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