The filters are part of an extensive refitting programme that Scottish Water is undertaking to meet tighter consent requirements.
“At Ashgill, Scottish Water Solutions’ requirement was to reduce the ammonia content and BOD, so the two new Dynasand Oxy sand filters are installed to promote nitrification, as well as removing solids,” explained project engineer Duncan Smith for engineering consultant Grontmij UK.
At Coalburn, a filter has been installed for final polishing through solids removal, while at Blackridge, two Dynasand Oxy sand filters are being used to remove ammonia.
The work at Ashgill, Coalburn and Blackridge, which includes suspended air flotation for improved aerobic secondary treatment followed by tertiary treatment by the sand filters, is being undertaken by Jacobs Engineering Services.
