AWWA JAW56674

Spontaneous bubble formation (or air-binding) can reduce atreatment plant's overall efficiency and interfere with watertreatment. Yet little research has been conducted to understandor mitigate this phenomenon. This article discusses thesources of bubble formation in treatment plants, their effects onthe water treatment process, monitoring techniques for evaluatingdissolved gases in water, and a method for determining bubbleformation potential.Air entrainment and ozonation are the key causes of dissolvedgas supersaturation and bubble formation. The authors conductedcoagulation/flocculation jar tests and filtration experiments toevaluate the effects of bubble formation on these processes.These experiments' key findings were then tested in a case studyat a water utility. The experiments showed that supersaturationaltered or prevented agglomeration and increased final settledturbidity during coagulation/flocculation and increased head lossduring filtration. The case study confirmed these findings. Theauthors concluded that bubble formation during coagulation andflocculation can potentially inhibit particle sedimentation and thatgas supersaturation as low as 0.05 atm during filtration candecrease filter run time and be an important contributor tohead loss. Includes 28 references, tables, figures.

Product Details

Edition:

Vol. 94 - No. 8

Published:

08/01/2002

Number of Pages:

10

File Size:

1 file , 360 KB