Dissolved air flotation in hot water

The effects of increased water temperature on dissolved air flotation have been measured. At temperatures up to 80°C the efficiency of air dissolution by spraying water over proprietory packing, bubble size distributions and the air-solids ratios required for iron floc flotation were found to be close to the values commonly found for those obtained at ambient temperature. Bubble rise rates at 80°C were three times faster than at 20°C and the onset of severe bubble coalescence at 80°C occurred at air dissolution pressures above 350 kPa.