The charcoal brick made from beer lees (CBBL) was investigated as the material for purification of lake water. The beer lees containing 67wt% water were first dried and then the dried beer lees were pressed at high temperature and pressure to make beer lees brick without any binder. The beer lees brick was carbonized in a low oxygen atmosphere to produce charcoal brick.
The CBBL is useful for the carrier of microorganisms and it is possible to reduce soluble organisms and soluble nitrogen as same as charcoal. The CBBL contains phosphorus at the ratio of about 2wt%, which is soluble in water. The addition of 20wt% CaCO₃ to the dried beer lees in the pressing process is beneficial to prevent solubilization of phosphorus in the CBBL. The CBBL does not have a weak point that it is abased in the purification column compared with the charcoal used in usual water purification.

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In this article, a number of preliminary concepts relating to the effects of some inorganic additives on electrokinetic behavior of El Maghara coal surface have been introduced. EL Maghara coal generally exhibits a point of zero charge (PZC) at a certain pH value. Removing the siliceous minerals from coal by deashing process would increase its PZC value. Solution chemistry models were used to elucidate the mechanism of action of some inorganic ions. Electrokinetic potential measurement is considered as one of the tools could be used to understand the nature of the interface and the mechanism of adsorption of solute species at the interface. Zeta potential values usually are considered as important information that determines the stability of colloidal dispersion.

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At the advent of the 21st century, mankind is facing a global environmental problem, and the indsutrial sector is required to take initiatives in the establishment of recycling society for efficienet utilization of natural resources. The coke-making process is considered suitable for a waste plastic recycling process, because the process involves coal carbonization in a high-temperature and reducing atomosphere. Through tests, it was found that waste plastics recycling process using coke ovens is feasible to recover coke, tar, light oil and gas from general waste plastics mixed in coal by carbonization in coke ovens without deterioratating the quality of coke.

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Legal framework for enhancing 3R society in Japan has been established during the past 10 years, based on the notion of Extended Producer Responsibility (EPR) . After the introduction of the law for sorted collection of containers and packaging, recycling of PET bottles and other plastics has been increasing, and burdened enterprises have shown preference for lighter packaging. Recycling system of consumer electronics, automobile and PC also started or are starting soon.
At the same time, trade flow of materials for recycling has been expanding among Asian countries, due to enhanced awareness of environmental protection and scarcity of natural resources, which should influence the domestic recycling market more in the future.

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This paper aims to clarify the issues and new tasks for building a materials-cycle sustainable society. Change in materials flow and materials balance generated from the mandatory recycling laws should be evaluated from the viewpoint of environmental impact assessment. Choice of technology is also very critical for the transformation from mass-waste society to materials-cycle sustainable society because technological option for recycling is very variable from source separation oriented recycling system to large-scaie fusing furnace oriented recycling system. Design of cost allocation system for recycling should be reconsidered from the pointo of view of fairness and incentive structure.

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Recently, the quantity of food waste has increased, and it has become a critical environmental problem. Then we have been studying on the food waste reclaiming technology by sub-critical water treatment. In this work, many kinds of useful materials (monosaccharides, organic acids, amino acids and so on) could be produced by hydrolysis of the food wastes. We expect that this technique will be of practical use in the near future.

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