Water Journal : Water Journal March 2011
industry news Control system failure modes were also designed to allow the treatment system to continue operation where possible. The biotrickling filter consistently achieved a discharge of less than 500 ppb H2S (> 99.8% H2S removal) and less than 3,200 OU (> 95% OU removal) during a 10-day performance testing period. The downstream chemical scrubber also met performance expectations, with a discharge of less than 100 ppb H2S and an average discharge of less than 1,000 OU. Monitoring Program Over the first year of operation, the biotrickling filters and chemical scrubbers have continued to meet performance expectations and have a high degree of reliability. The new covers and extraction system have also been highly effective, with negative pressures consistently achieved under covered areas. Generally the community has been satisfied with the reduction in odour emissions, with no odour-related complaints received in the four months to June 2010. A team of local residents was engaged to report on odour events before and during commissioning. Reports declined by more than 90 per cent as a result of the upgrade, and the team reported that the residual odour is less annoying than before. Complaints about odours from local residents necessitated a major upgrade at Woodman Point, Perth's largest WWTP.
Water Journal April 2011