AWWA WQTC58794

Water utilities are facing the challenge of providing higher levels ofdisinfection while having to lower concentrations of disinfection byproducts. A keyfactor for meeting these goals is the removal of naturally occurring organic matter(NOM). One alternative that has emerged is a magnetized ion exchange (MIEX) process.It has been demonstrated to be highly effective in removing both low and high molecularweight dissolved organic carbon (DOC) fractions from a range of waters, and works wellin conjunction with coagulants for removal of a broad range of organic weight fractions.This process can be applied as a series of mixed contactors to treat raw water ahead ofcoagulation. The resin is magnetized to facilitate recovery in a settling compartment thatis located downstream of the contactors. Most of the recovered resin is returned to thecontactors, but a portion is regenerated to provide a steady state condition under whichion exchange capacity can be maintained in the system. A small fraction of fresh resin isadded to compensate for any losses. This project provides an evaluation of theperformance of the MIEX process under widely different conditions. Effect on removalof NOM and control of disinfection byproduct formation are examined along withassessments of the effects on selected inorganic constituents that include bromide,sulfide, arsenate, arsenite, and perchlorate. Interaction with other plant elements thatinclude disinfection and coagulation-based processes is another critical area that wasassessed.Evaluations for this work are a part of an AWWARF study to investigate theeffectiveness of the MIEX process in source waters with a wide range of characteristics,such as high DOC - low alkalinity, high DOC - high alkalinity, medium DOC - mediumalkalinity, and low DOC - high alkalinity. Bench and pilot scale testing is beingconducted at various utilities to provide these assessments. Includes 8 references, table, figures.

Product Details

Edition:

Vol. - No.

Published:

11/02/2003

Number of Pages:

13

File Size:

1 file , 410 KB