Dissolved Air Flotation (DAF) Pilot System Achieves Removals In Excess Of 95 Percent

The aluminum casting facility of a producer of semifabricated aluminum products utilizes a closed-loop contact water system that supplies water to multiple DC casting pits. An existing induced air flotation (IAF) system was used for the reduction of TSS, NTU, oil and grease, followed by a cooling tower. The treated and cooled water was then reused in the caster as contact water. The IAF had a removal efficiency of approximately 40 percent, required regular maintenance attention, operated at 125 HP and used an excessive amount of chemistry, resulting in extraordinarily high operating costs.