AWWA WQTC55022

The effluent of wastewater treatment plants contains between 5 and 15 mg/L of dissolved organic carbon (DOC), with biological treatment removing a majority of the organic matter present in untreated wastewater. Characterizing this remaining bulk organic matter and its constituents, and removing them from secondary effluents was the aim of this study. A bench-scale filtration cell was used for testing different microfiltration and ultrafiltration membranes. The main problem is the fouling of the membranes by effluent organic matter (EfOM) which prevents an efficient operation. Isolation of effluent organic matter from the WWTP in Boulder, Colorado, was done with non-ionic macroporous resins (Amberlite XAD 8 and XAD 4). The obtained isolates were used to identify the DOC fraction that contributes most to the fouling. Experiments showed significant flux decline over a period of one to two hours in stirred cell tests. Of the total DOC delivered to the membrane surface, only a small percentage contributes to the fouling layer. Interestingly, a second passage of the obtained permeate through the membrane still induces flux decline in a second stage and fouling, although to a lesser extent. Size exclusion chromatography revealed that mainly proteins and polysaccharides, which can be attributed to the colloidal fraction of residual organic matter, cause the most severe fouling. Includes 16 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

01/01/2001

Number of Pages:

12

File Size:

1 file , 290 KB