Final/Primary Settlement Tanks

Carlow Concrete offer a state of the art solution for precast circular tank structures which incorporate launder or weir channels.
Precast Launder channels are cast integrally with the external wall unit. Both inboard and outboard channels are available dependent on our customers requirements. A precast concrete cone unit is located in the middle of the cast insitu conical floor. The cone unit is prepared for each site specific application. Electrical conduits and pipe couplings/starters are cast-in during production ensuring the installation on site is fast, accurate, safe and cost effective.

Our inhouse design team prepare design calculations, drawings and specifications in compliance with Eurocode or British Standard requirements, all of which is protected by our extensive professional indemity insurance cover.
Final settlement tanks (FSTs) are similar in design to primary settlement tanks and are an integral part of the activated sludge process. This type of tank settles out the biological material flowing from the secondary treatment plant producing supernatant that has low levels of organic material and suspended matter that is suitable for additional tertiary treatment or discharge into a water course.

Humus tanks perform a very similar function in conjunction with the more traditional percolating filter type plants that are still in common use. In this application the settled solids are normally extracted for treatment in a sludge processing plant.