A B S T R A C T : In the Water Framework Directive, a list of priority substances that are deemed to be persistent, toxic, and liable to bioaccumulate have been identified. Within this list, a range of polycyclic aromatic hydrocarbons (PAHs) and certain trace metals are relevant to the steel industry. This study summarizes work carried out by Tata Steel Europe (Rotherham, U.K.) to characterize the emissions of PAHs and trace metals from wastewater streams at one of its main integrated steelworks in the United Kingdom over a 3-year period (2010 to 2012). The emissions inventory revealed that PAH emissions to water were almost entirely attributable to the cokemaking process, with emissions factors ranging from 20 to 55 mg/tonne of coke. Furthermore, analysis of the PAH distribution in coke oven effluents revealed that medium-and high-molecular-weight PAHs were associated with the suspended solids (particle-bound). Regarding trace metals, both ironmaking and steel making processes were the most important emission sources. Water Environ. Res., 87, 132 (2015).K E Y W O R D S : priority hazardous substances, Water Framework Directive, polycyclic aromatic hydrocarbons, trace metals, emissions inventory, integrated steel industry.

Water resources play an important role in industrial, agricultural, and public activities. Chlorinated paraffins (CPs) in wastewater generated by these activities provide an important source of CP contamination. In this study, the occurrences of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were simultaneously studied in a typical sewage treatment plant (STP) near China’s second-largest oil production base over a 1-year period. High levels of SCCPs and MCCPs (3809 ± 670 and 4803 ± 478 ng/L) were found in the influent due to receiving 75% of industrial wastewater. C14-CPs was the predominant congener group, accounting for 37% of the total CP concentrations. The dissolved removal efficiency of CPs was 83.5%. Mass balance results demonstrated that 3.2% of the initial CPs was found in the final effluent, and 66.3% of the initial CPs was found in the dehydrated sludge, while 30.4% of the initial CPs was lost due to the biodegradation and volatilization. This indicated that sorption onto sludge was the main fate of CPs in wastewater treatment. High mass fractions of CPs were found in the final effluent and dewatered sludge in the winter season due to the low biodegradation, biotransformation, and volatilization.