AWWA ACE91077

The removal of natural aquatic dissolved organic matter (DOM) by conventional coagulation using ferric chloride was investigated. DOM was isolated by reverse osmosis from the Suwannee River in southern Georgia and from Lake Allatoona in northwestern Georgia. The two most significant differences between the waters are pH and organic carbon concentrations. Extensive jar testing identified regions of removal based on initial concentration of DOM, coagulant dosage, and pH conditions. DOM was removed by coagulation predominantly through adsorption onto solid hydroxide precipitates. At lower pH conditions corresponding to higher coagulant doses, the formation of iron-DOM precipitates contributed to removal. The combination of these mechanisms provided optimum removal of DOM. Fast atom bombardment mass spectrometry (FABMS) was used to characterize the molecular weight distributions of DOM before and after coagulation. Trends in the shape of the spectra correlated well with data for removal of DOM and provided evidence indicative of the mechanisms of coagulation.

Product Details

Published:

01/01/1991

ISBN(s):

0898675901

Number of Pages:

39

File Size:

1 file , 1.2 MB