Origin and Fate of Hg Total in the Jundiai City (Brazil) Wastewater Treatment Plant

摘要

Measurements of mercury in the Juindai city wastewater treatment plant are presented. The Juindai city is located in the Rio Jundiai hydrographic basin with a drainage area of approximately 1,200 km~2 and an annual medium flow of 8.0 mVs. Around one million people are living in this area, where intense industrial activities are developed. During a monitoring period, performed in 37 different days, the treatment system, composed by two 75,000 m~3 aerated lagoons and followed by four 35,000 m~3 sedimentation lagoons, showed average mercury concentration values of 170 ng/L and 55 ng/L for the affluent and effluent respectively. Approximately 1.0 m~3/s of domestic and industrial wastewater mixture, that is daily generated by the 400,000 inhabitants of Juindai city, is treated and discharged in to the river.