Characteristics of typical heavy metals removal abilities in Fuzhou domestic wastewater treatment process

摘要

In this paper, the removal characteristics of five heavymetals (Mn, Fe, Zn, Cr,As) in two urban wastewater treatment plants calledAand B in Fuzhou were studied. The results showed: (1) The influents of these two wastewater treatment plants weren???t seriously polluted by heavy metal heavily except for Mn and Fe, this may result from the environmental background of Fuzhou; (2) A takes A/O process as the biological unit, the removal efficiencies for these heavy metals of the whole process ranged from 7.5% for Zn to 93.1% for Fe. (3) B utilizes CASS process for secondary treatment, it yielded lower removal efficiencies than A/O process on the whole, ranging from28.5%forMn to 88.2%for Fe except Zn; (4) BothA and Bwere excellent in removing Fe while had little removal efficiency for Zn, thismay result fromthe re-dissolution of particulate Zn; (5) the removal capacities for heavy metals of these two wastewater treatment plants were calculated respectively, ranging from0.03 kg ???d-1 to 18.10 kg ???d-1.