Reducing environmental impact on the basis of risk calculations

Resumo

The environmental risk due to atmospheric pollution from coke plants is assessed for both organized and unorganized sources of emissions in the byproduct-capture, benzene-rectification, and tar-processing shops and the system for biochemical wastewater treatment. It is found that 19.4% of all the organized sources correspond to acceptable levels of chronic noncarcinogenic environmental risk; 30% to high risk; and 50.6% to very high risk. A system of hydraulic breather valves is proposed for utilization of the emissions in the byproduct-cap ture shop. For the tar-processing and benzene-rectification shops, delivery of the emissions to the direct coke-oven gas line is recommended. For the emissions from the biochemical wastewater treatment system, collection and purification by sorption and biochemical treatment is proposed.