Environmental improvement works in Stonecutters Island Sewage Treatment Works (SCISTW), i.e. covering sedimentation tanks, installation of deodouriser in SCISTW under HATS 2A
Three-step mitigation measures for odour control are taken at the existing sedimentation tanks of SCISTW:
- Installation of fibreglass reinforced plastic (FRP) covers with a gas-seal design on the existing sedimentation tanks, flow channels and chambers;
- Installation of an air extraction system to collect foul gas within the covered tanks, channels and chambers; and
- Treatment of foul gas by "Biotrickling Filter" technology before discharge into open air. The "Biotrickling Filter" is a reliable and environmentally friendly biological odour removal technology with a low life-cycle cost and minimum operation and maintenance requirements. It can remove 99 per cent or more of hydrogen sulphide gas (H2S), the main source of odour in STW, for effective odour control.