Surrogate study for dioxins from municipal waste incinerator in startup condition: applicability as a dioxin control indicator and an organohalogen emission warning

Dioxins and their surrogates were continuously monitored during the startup of two municipal waste in cinerators (MWIs). The surrogates studied included low-volatility organohalogen compounds (LVOH) sampled by online systems, as well as chlorobenzenes (CBs) and chlorophenols (CPs). The changes in levels of LVOH, CBs, and CPs corresponded well with the trend of the toxicity equivalent quantity (TEQ). The correlation of LVOH with TEQ was fairly good, whereas that of CBs and CPs with TEQ was not consistent. The correlation of LVOH with TEQ involved a memory effect related to the delayed emission of less volatile compounds. The isomer analysis of the dioxins present under startup conditions showed evidence of the memory effect, i.e., highly chlorinated isomers were emitted slowly, whereas low-chlorinated isomers and LVOH decreased rapidly as the temperature rose. LVOH cannot act as a perfect dioxin surrogate, but it can give a versatile, quick, and comprehensive warning of the presence of organohalogen compounds because it is free from the memory effect and covers many kinds of organohalogen compounds, including dioxins.