bnr-hk-gac-water
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  4. Exploring GAC Use for Drinking Water Treatment in Hong Kong

Exploring GAC Use for Drinking Water Treatment in Hong Kong

With our strong local and global technical expertise, we have been appointed to investigate the retrofitting of filters in water treatment works with granular activated carbon (GAC) in Hong Kong.

Location

  • Hong Kong

Client

  • Water Supplies Department, HKSAR Government

Project Status

  • completion in 2022

In recent years, very low concentrations of contaminants such as perfluoroalkyl substances (PFAS), pharmaceutical residues and pesticides have been detected in local water environment in Hong Kong, leading to concerns on a potential rise in future. In addition, there more reported cases in past years on taste and odour problems in some raw water sources in Hong Kong caused by natural occurring 2-methylisoborneol (MIB).

Hong Kong Government’s Water Supplies Department hence plans to formulate a contingency plan to safeguard drinking water from emerging contaminants and taste and odour problems by reviewing the feasibility of retrofitting existing filters with GAC and its implementation and performance. Key stages include:

  • Review the feasibility of retrofitting of filters with GAC and the necessary associated changes in treatment process at the facilities for the removal of contaminants such as PFAS, pharmaceutical residues, pesticides and MIB;
  • Compare the feasibility, performance and cost effectiveness of GAC with incorporating advanced oxidation process and biological activated carbon process at water treatment works (WTW) in removing contaminants in raw water;
  • Conduct a trial on retrofitting of one filter bed at Siu Ho Wan WTW with GAC for operational characteristics evaluation; and
  • Prepare implementation plans for replacement of anthracite by GAC as filter media at the facilities and the O&M plan of the GAC filter as a contingency plan for tackling contaminants in raw water

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