On-line Monitoring Equip- ments of Dioxins and their Precursors for Incineration Plants

*1 Yokohama Dockyard & Machinery Works *2 Yokohama Research & Development Center, Technical Headquarters It usually takes a few weeks to analyze dioxins concentration in flue gas from MSW incinerators by official method. In order to reduce the required time for analysis, we have developed an on-line measuring equipment for pentachlorodibenzofuran (P5CDF) and a real-time measuring equipment for trichlorobenzene (T3CB). The following results were obtained from field tests carried out using these equipments. (1) The concentration of DXNs emitted can be estimated and monitored by measuring the concentration of P5CDF contained in flue gas using a vacuum ultraviolet ionization mass spectrometer (VUV analyzer) after automatic concentration of P5CDF. (2) Optimum operating conditions to reduce dioxins emission can be obtained by the T3CB measuring equipment which relates to dioxins' behavior inside furnaces real-timely, and (3) These equipments can be applied in adjusting operating conditions during the trial operation of an incineration plant by monitoring them and for basic research and development.