| Disinfection By-Product Formation and Control During Chloramination Contributor(s): Speitel, Gerald E. Jr. (Author), Pope, Phillip G. (Author), Collins, M. Robin (Author) |
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ISBN: 184339930X ISBN-13: 9781843399308 Publisher: AWWARF OUR PRICE: $237.60 Product Type: Paperback Published: July 2005 * Not available - Not in print at this time * |
| Additional Information |
| BISAC Categories: - Science | Chemistry - Industrial & Technical - Technology & Engineering | Environmental - General - Science | Applied Sciences |
| Dewey: 628.166 |
| Series: Water Research Foundation Report |
| Physical Information: 0.51" H x 8.25" W x 11" (1.23 lbs) 244 pages |
| Descriptions, Reviews, Etc. |
| Publisher Description: In response to current and anticipated disinfection by-product (DBP) regulations, many utilities have begun to use chloramines as a secondary disinfectant. Chloramination produces DBPs such as haloacetic acids (HAAs), trihalomethanes (THMs), and haloacetonitriles (HANs) in lower concentrations than chlorination. Previous research has demonstrated that dihalogenated haloacetic acids (DXAAs) are the most commonly formed HAAs during chloramination. Some utilities may have difficulty meeting the new maximum contaminant level (MCL) for HAAs because chloramination does not limit the formation of DXAAs to the same extent as it does other DBPs. The objectives of this project were to: 1. better understand the reactivity of key natural organic matter (NOM) fractions and the effects of treatment processes with respect to dihaloacetic acid (DXAA) formation, 2. better delineate the influence of pH and Cl2/N ratio on DXAA formation, 3. characterize DXAA formation kinetics and the impact of treatment processes on the kinetics, especially the impact of prechlorination, 4. calculate the rate and extent of DXAA formation at elevated summer water temperatures, and 5. determine the effect of bromide concentration on DXAA speciation and kinetics. The research consisted of laboratory experimentation, mathematical modeling, and sampling of selected treatment plants and distribution systems. The first phase consisted of batch screening experiments on two water sources of differing water quality, Lake Austin, Texas and Metedeconk River, New Jersey. The selected waters were subjected to various treatments and NOM fractionations. Overall, 12 different waters were studied. Additional batch experiments wereundertaken to further study the most important variables that were identified in the initial batch screening experiments. DXAA formation kinetics were studied in four waters by measuring DXAA concentrations over chloramination contact times of 0.5 to 72 hours. Prechlorination times of 5 and 20 minutes were tested. Mathematical models were developed to predict DXAA formation during chloramination based on water quality and chloramination conditions. |