Waste Treatment Technologies in Japan, including Ash-Melting

Concern over dioxin emissions led the Japanese government to launch a novel thermal technology thrust Technologies for the 21st century, generally involving gasification or pyrolysis systems, while ash recycling and disposal problems were addressed by melting this ash, followed by granulating the slag melt in a water quench. These programs also include tight emissions limits, investment in new efficient facilities with better emissions control technologies and alternatives to MSW combustion. Major grounds for introducing such new thermal processes has been the claim to be environmentally more acceptable than incineration, especially with respect to total output of dioxins and avoidance of landfill. Energy recovered from MSW, a consideration neglected in the past, is also ascending. In Japan MSW elimination is still a public service, severely constrained and thus subject to institutional inefficiencies, such as redundant treatment capacity, high operating cost, and low energetic efficiency.