Managing the Environment

Odour Management

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:

1. Installation of fibreglass reinforced plastic (FRP) covers with a gas-seal design on the existing sedimentation tanks, flow channels and chambers;
2. Installation of an air extraction system to collect foul gas within the covered tanks, channels and chambers; and
3. 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.