Species-dependence of cyanobacteria removal efficiency by different drinking water treatment processes

摘要: Abstract Accumulation and breakthrough of several potentially toxic cyanobacterial species within drinking water treatment plants (DWTP) have been reported recently. The objectives this project were to test the efficiency different barriers in removal. Upon observation blooms, intensive sampling was conducted inside a full scale DWTP at raw water, clarification, filtration oxidation processes. Samples taken for microscopic speciation/enumeration microcystins analysis. Total cyanobacteria cell numbers exceeded World Health Organisation local alert levels (6,90,000 cells/mL). Extensive accumulation sludge beds filters, interruption observed. Aphanizomenon cells poorly coagulated they not trapped efficiently sludge. It also demonstrated that passed through retained over filter. However, Microcystis, Anabaena, Pseudanabaena adequately removed by clarification non into DWTPs could result severe disruption leading plant shutdown. Application intervention threshold values restricted does take consideration major long term risk toxins release. Thus, regime adapted occurrence intensity is recommended.