Would cascading water flow in the treatment plant be considered an air stripping type of treatment? How efficient could it be?

Some stripping of VOCs can occur any time air and water mix. However, the efficiency of VOC transfer in cascading water flow would be very low compared to a conventional air stripper using counter-current mass transfer unit like a tray air stripper. Cascading water creates very little surface area for air to contact for VOC transfer (low air/water ratio), resulting in very little VOC removal from the water.

Tray air strippers have been used in water treatment applications to vastly lower the volume of off-gas in cases where air treatment is required (such as in the aeration step on a SBR). The water is routed through the tray stripper prior to the main treatment unit (SBR), which eliminates the need to treat the high air volume exiting an aerobic bio-treatment process.