Flow analysis and fate of mercury in Chinese polyvinyl chloride production

The production of polyvinyl chloride (PVC) via the calcium carbide process is one of the most important sources of anthropogenic mercury (Hg) in China. However, detailed information about the quantity and fate of Hg in the PVC production process is unavailable. In this study, the fate and transport of Hg in PVC production was quantified and determined via material flow analysis (MFA). In addition, the content and fate of Hg in deposits on the inner surface of converters and downstream pipelines were quantified. The results indicated that the average Hg output accounted for 89.29 % of annual Hg input and that 10.72 % of the Hg was “missing”. An average 80.77 % of the Hg input was discharged into the waste catalysts, pipeline sediments and waste activated carbon. The waste catalysts, pipeline sediments and waste activated carbon discharged from the PVC production process should be properly disposed as hazardous solid waste.