The removal of cadmium from the waste products of scallop processing was examined. In Hokkaido, the production of scallops has been increasing annually, and waste product appears to be increasing in proportion to the processing volume.
Because the waste products of scallop, especially the mid-gut gland, contains a large quantity of heavy metals, such as cadmium, effective use is impossible. Studies of cadmium distribution in various tissues which were made during each of the seasons showed that the concentration of cadmium is the highest in the mid-gut gland and the increases in accordance with the growth of the animal.
Cadmium can be removed by one process as described below.
(1) The mid-gut gland is soaked in a dilute sulfuric acid solution which dissolves the cadmium.
(2) When an electric current is passed through the solution, the cadmium is deposited on the cathode surface.
Treatment using the above method removed more than 90% of the cadmium from the mid-gut gland. After the removal of cadmium, the dried and crushed wastes products of the scallops were used as feed and fertilizer materials.

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Up to this time, demolished waste has been treated not strategically but“trial and error”in Japan.
This study is aimed at developing an efficient supporting system for hauling and transportation of the demolished waste under the confusing conditions of post disaster.
This system also supplies visual information which will enable rapid decisions by using a Geographic Information System.
As a result of this study, a reasonable supporting system for demolished waste treatment could be concretely showed by using this developed model and simulation.

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In order to assess the progression of the degradation characteristics of cellulose and lignin under sulfate reducing and methanogenic conditions, four pilot scale simulated landfill columns were prepared and operated.
According to the results of this research, very favorable pH and extreme reducing conditions prevailed in partially and fully saturated sulfate reducing reactors.
Higher concentrations of hydrolysis products of cellulose (i.e., glucose) and lignin (i.e., aromatic lignin derivatives) along with higher COD and TOC in the leachates from the sulfate reducing columns as compared to those from the methanogenic columns, indicated a faster rate of mineralization of cellulose and lignin loaded in the columns.
In the sulfate reducing columns, methane and carbon dioxide gas production was effectively suppressed.

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Cooking and bleaching conditions of chemical pulp are mainly high alkaline. We screened for microorganism producing alkaline lignin-degrading enzymes using the alkaline cooking of Manila hemp as a medium. One fungus screened was identified as Aspergillus terreus. This fungus secretes alkaline lignin-degrading enzymes (lignin peroxidase, manganese peroxidase, phenol oxidase) into the medium.
This fungus and its enzymes may be useful for the treatments of alkaline black liquor or bleaching waste and biobleaching of pulp.

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Air-sorting is widely used for solid wastes separation for its low-cost and easy-operation. However, it has the disadvantage of unstable performance due to fluctuation in the properties of fed materials, such as particle size and shape. Yet, little is known about the characteristics of air-sorting, and factors which affect separation efficiency have not been clearly reported. This paper presents some findings on the basic characteristics of air-sorting, and a new method for separating shredded aluminum and copper with a high separation efficiency. Preliminary tests to examine the relationship between recovery ratio and wind velocity showed that recovery ratio can be described as an integral calculus of normal distribution as a function of wind velocity. Experiments using rectangular block samples to study the effect of particle shape showed that the wind velocity whereat the particles are blown-up depends on the thickness of particle. This characteristic was supported by a calculation based on a terminal velocity equation. Based on these findings, three alternative air-sorting methods were suggested and tested. A proposed method to roll feeds before sorting showed high separation efficiency with a maximum aluminum and copper recovery ratio of 98-99%, which is higher than 87% of the conventional method.

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Interference of 15 coexistent gases on the continuous CO analyzers with infrared absorption for the flue gas were investigated, and the measured values by the different types CO analyzers were compared at a municipal waste incinerator.
CO₂and N₂O interfered with the CO analyzers. Then, there was a difference of about 4 ppm between the measured values from the double beam IR CO analyzer and those from the single beam IR CO analyzer. In order to precisely measure low CO concentrations, it is necessary to correct the measured values from the CO analyzers by taking their characteristics and mean concentrations of CO₂and N₂O concentrations in the flue gas.

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