Sand filter tertiary polishing plant

Designed to remove excess suspended solids (SS) and biological oxygen demand (BOD) from wastewater treatment plants. The WPL  sand filter meets stringent discharge consent standards above what is normally expected from a biological process or an industry standard clarifier. The WPL Sand Filters will remove typically a minimum of 60% SS and 40% BOD dependent on particle size distribution.

Why choose a Sand Filter:

 Low maintenance and operating costs

  • No chemical dosing consumables
  • Minimal serviceable parts reduce planned and reactive maintenance risks
  • Timed backwash sequence combines air scour and backwash
  • Backwash pump for sludge discharge to ensure minimal manual intervention required

System design and manufacture

  • Influent can flow by gravity or pumped into the filter unit
  • Backwash removes solids trapped in sand filter media
  • Waste backwash water is returned to the plant for co-settlement and re-treatment
  • No need to inhibit inflow to filter during backwash cycle
  • Above and below ground installations
  • Available in a range of sizes to tackle flow rates
  • Single units can cope with population equivalents up to 600 but can also be linked in parallel to treat higher populations
  • Can be retrofitted where an existing system is failing discharge consent conditions, for both SS and BOD
  • Manufactured in glass reinforced plastic (GRP) with an ultra violet (UV) stabilised external gel coat finish to extend the asset life to 25 years

Technical specification

Download the Sand Filter datasheet within the Assets section on this page.


Image (above) of an above ground option