AWWA WKICO66065

Arsenic is a common trace inorganic contaminant present in many US drinking watersupplies and its current MCL (maximum contaminant limit), based on concerns about thelong-term health effects is 10 µg/L (USEPA, 2001). The Albuquerque Bernalillo CountyWater Utility Authority (the Authority) has 92 wells of which41 have arsenic concentrations greater than 10 µg/L. With respect to the arsenic regulation,the Authority is one of the most severely impacted utilities in the US.Bench and pilot studies were performed at the University of Houston and at the West MesaPump Station in Albuquerque, respectively, to develop a ferric coagulation-directmicrofiltration (C/MF) process. Process variables studied included arsenic speciation, initialarsenic concentration, pH, coagulant (ferric) dose, pre-formed vs. in situ coagulant use,coagulation time (prior to direct filtration), influence of co-occurring inorganic species (silicaand sulfate), mixing intensity, filter pore size, filter flux and backwash interval. These studiesproved the ability of the C/MF process to remove arsenic to meet the new MCL, andestablished design criteria for the full-scale 5.3-MGD Arsenic Removal DemonstrationFacility (ARDF), which went into operation in July 2007. Design and operational details ofthe ARDF are described in this paper, along with a discussion of findings of the bench andpilot studies. Includes 4 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

01/01/2008

Number of Pages:

14

File Size:

1 file , 350 KB