Masaaki Hosomi

Tokyo University of Agriculture and Technology
(2-24-16 Nakamachi, Koganei, Tokyo 184-8588, Japan)

Abstract

About 30 years have already passed since measures dealing with PCBs such as the prohibition of manufacture, import and use in open systems were introduced. The emission of PCBs to the environment from electrical machinery and apparatus in use or being stored which contain PCBs has been a source of concern. Not only incineration but also chemical treatment processes such as chemical dechlorination and supercritical water oxidation were covered under the "Waste Disposal and Public Cleansing Law" of 1998. To begin with, this paper outlines the history of the PCB contamination problem and the chemical treatment technologies proposed. As a future problem, the necessity of re-examining the PCB problem from the viewpoint of dioxins is described. In addition, the problem concerning the practical application of solvent cleaning technology and vacuum heating separation technology as processing technologies of PCB-contaminated waste is discussed.

Key words: polychlorinated biphenyls (PCBs), waste PCB, PCB contaminated matter, chemical dechlorination technology, supercritical water oxidation technology, solvent washing technology, vacuum heating separation technology