Various kinds of industrial dust wastes were recycled by a wet ceramic process. Compounding various dusts gave allowed us compositional variation of dust wastes which originated from various places and conditions. One of the main problems for recycling wastes is caused by compositional variations. Success in recycling depends on how to control compositions and maintain the allowed purity level in the wastes. Grouping of dust wastes into three categories and compounding were introduced to raw material preparation processes for the successful recycling of various dusts. Pretreatment processes were also important to stabilize heavy metals in the raw materials. These processes consist of ion exchange, control of electrolyte concentration and pH etc. After these processes, industrial dust wastes were turned into safe, ecological construction materials such as bricks or lightweight aggregates by a final sintering process.

Diamond-like carbon (DLC) films were deposited on p-type (100) Si wafers using a plasma-enhanced chemical vapor deposition system and their structural bonding characteristics and mechanical properties were investigated as a function of the mixture ratio of methane-hydrogen gas and the bias voltage. It was found that the deposition rate increased with an increase in the flow rate of methane in the gas mixture and an increase in bias voltage. The sp3/sp2 ratio of carbon in the films and the hardness of the films increased with an increase in the flow rate of hydrogen in the gas mixture and an increase in the bias voltage.