Abstract:
Halcrow Scotland were appointed by Grampian Regional Council (now North of
Scotland Water Authority) in April 1993 to carry out the Aberdeen Wastewater
Treatment Feasibility Study. The study started with a verification of the flows and
polluting loads generated within the catchment followed by a review of the treatment
technologies available. The purpose of examining the available technologies was to
ascertain the land areas required. Different technologies had different land
requirements, and it was important to evaluate this for the site selection stage.
Inevitably, conventional activated sludge treatment processes required the greater land
take, but it was the only proven technology as far as the client was concerned.
Other treatment processes, loosely termed "small footprint", could be accommodated
within a much smaller area. The most promising of these processes was Biological
Aerated Flooded Filters (BAFF), but at that time there were very few plants operating
in the UK and none in Scotland. Halcrow recommended that the client establish pilot
plant trials of the BAFF process. For minimal land take lamella plate separators would
be required in the primary treatment stage and it was decided to include this compact
settlement process (with or without chemical assistance) in the pilot plant trials.
