Organic-waste disposal in high-temperature metallurgical systems

Abstract

Globally, organic waste is the largest component of hazardous waste. Chlorine-bearing organic waste is a particular environmental hazard. The main disposal method for organic waste is high-temperature combustion in special incinerators and in rotary cement furnaces. However, combustion is associated with the risk that secondary supertoxics such as dioxins and furans may be formed. Comparison of dioxin formation for waste combustion in incinerators, cement furnaces, and high-temperature metallurgical systems (oxygen converters) shows that oxygen converters are preferable, thanks to the high temperatures, intense heat and mass transfer, active oxidizing atmosphere, the presence of highly active basic slag, rapid cooling, and complete combustion of the waste gases. Data on the content of 17 dioxin and furan isomers in the dust transported by exhaust gas from converters containing paper and plastic waste at OAO EVRAZ ZSMK show that the total concentration is considerably below European standards for waste gases from stationary sources. No significant difference is observed in the concentrations and isomer profile of dioxins and furans in the experimental and standard melts.