Spontaneous bubble formation (or air-binding) can reduce a
treatment plant's overall efficiency and interfere with water
treatment. Yet little research has been conducted to understand
or mitigate this phenomenon. This article discusses the
sources of bubble formation in treatment plants, their effects on
the water treatment process, monitoring techniques for evaluating
dissolved gases in water, and a method for determining bubble
formation potential.
Air entrainment and ozonation are the key causes of dissolved
gas supersaturation and bubble formation. The authors conducted
coagulation/flocculation jar tests and filtration experiments to
evaluate the effects of bubble formation on these processes.
These experiments' key findings were then tested in a case study
at a water utility. The experiments showed that supersaturation
altered or prevented agglomeration and increased final settled
turbidity during coagulation/flocculation and increased head loss
during filtration. The case study confirmed these findings. The
authors concluded that bubble formation during coagulation and
flocculation can potentially inhibit particle sedimentation and that
gas supersaturation as low as 0.05 atm during filtration can
decrease filter run time and be an important contributor to
head loss. Includes 28 references, tables, figures.
| Edition : | Vol. 94 - No. 8 |
| File Size : | 1
file
, 360 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 08/01/2002 |
