AWWA JAW59700

This two-phase study investigated iron (Fe) coagulationfollowed directly by microfiltration (CMF) asa treatment for removing arsenic (As) fromgroundwater in Albuquerque, N.M. In the first phase,bench-scale tests were conducted to determine theeffect of As oxidation state, pH, Fe dose, silica concentration,mixing time, and filter pore size on As removal.The second phase consisted of a pilot study to investigatesuch variables as pH, Fe dose, mixing time andenergy, filtrate flux, and backwash interval.The most important variables controlling As removalwere pH and Fe dose. As removals to <2 ¿¿g/L wereachieved using either a 7 mg/L Fe dose without deliberatepH reduction or a smaller dose of 1.9 mg/L Fe after additionof sulfuric acid to reduce pH to 6.4. Continuousthree- to five-day operation of the CMF pilot-scale processverified efficient filter performance and showed noincrease in transmembrane pressure, even after five days.CMF represents an innovative treatment technologyfor removing arsenic (As) from groundwater. By eliminatingthe flocculation step, the process offers waterproviders savings in both space and cost. Designed to becompact, CMF is especially useful for smaller systems orlarger systems where space is a constraint. Includes 25 references, table, figures.

Product Details

Edition:

Vol. 96 - No. 4

Published:

04/01/2004

Number of Pages:

10

File Size:

1 file , 430 KB