In 2020, the Ruthven Water Treatment Plant, owned by UWSS and located at Kingsville, ON, started the upgrades of the existing clarification process to increase operational flexibility and overall efficiency. For this project, Napier-Reid designed and supplied a Dissolved Air Flotation (DAF) equipment for the retrofit of the clarifier system. DAF has become an accepted process in drinking treatment systems for the removal of suspended solids, algae, and other dissolved matter. It is a process that relies on uniting air bubbles coming from the solution with suspended particles and subsequently, raising the suspended particles to the surface for removal

The DAF system was designed to treat an influent flow rate of 9.8~70ML/d (408~2917m3/h), producing clarified water that meets the performance requirements. The DAF mechanism consists of one inlet well, one flocculation well with eight vertical flocculators, one flotation tank, one air-saturated water dispersion assembly, one set of scum skimmer mechanism including four skimming arm assemblies & four scum troughs, one sludge scraper mechanism including two sludge scraper arm assemblies, one effluent trough with an adjustable weir, scum baffle, and support structure.

The scope of supply also includes one inline dynamic mixer, one set of air saturation system, one power panel to supply power to all motors in the proposed DAF package, and PLC control panel.