AWWA WQTC64092

This presentation describes an innovative bench-scale method for determining ozonedemand in test waters in the field along with three case studies to demonstrate theeffectiveness of the method. Current industry practice for determining ozone demand isoften calculated by comparing water quality data with demand values from literature, amethod that can underestimate demand if unknown or unquantified contaminants arepresent. The method described in this paper is an effective and efficient way ofaccurately ascertaining ozone demand for properly sizing ozone treatment equipment.The method described in this paper uses an onsite ozone generator and distilled water toquantify gas transfer relationships. The ozone is sparged into the distilled water inmultiple trials of varying duration with the ozone concentration being measured at theend of the sparging using the standard indigo method. A curve of measured ozone versustime is used to develop transfer equations relating ozone transfer to ozone concentration.These relationships are then used to ascertain gas transfer into the test water during ozonesparging tests and subsequent ozone residual testing. The results of these tests allow acalculation of ozone demand in the test water. Three case studies are presented todemonstrate the method. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2006

Number of Pages:

17

File Size:

1 file , 430 KB