Disinfection By-product Precursor Removal by Enhanced Softening and Coagulation PDF Download

Author: Holly Louise Shorney
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description

Author:
Publisher: DIANE Publishing
ISBN:
Category : Disinfection and disinfectants
Languages : en
Pages : 270

View

Book Description

Author: Vedat Uyak
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659428609
Category :
Languages : en
Pages : 164

View

Book Description
Chlorination is the most commonly employed chemical disinfectant in drinking water treatment nowadays. However, several studies reported that chlorination of organic matter in fresh water resulted in formation of disinfection by-products (DBP). Because of concerns over the health effects of organic by-products of chlorination, the use of alternative disinfectants of chloramines, ozone, and chlorine dioxide as primary or secondary disinfection agents is increasing. However, each of these alternatives has also been shown to form its own set of DBP. Concerns regarding the potential health effects of DBP prompted several industrialized countries to develop a number of regu-lations. The disinfectant/disinfection by-product (D/DBP) regulation in United States of America (USA) has set maximum contaminant levels for trihalomethanes (THM) and haloacetic acids (HAA) of 80 and 60 ug/l, respectively.

Author: Colleen M. Kenny
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 139

View

Book Description
Treatment facilities out of compliance with EPA regulations are often not using optimal chemical treatment. Determination of the most effective chemical type, combination and concentration can aid in reduction of disinfection by-product precursors. The effects of optimal chemical treatment using enhanced coagulation and enhanced softening was tested on three surface waters (two reservoirs and one lake sources), and one ground water (alluvial wells). Results indicated enhanced coagulation was more effective at removing DBP precursors from waters with higher initial UV-254 absorbance values and lower alkalinities while enhanced softening was more effective for waters with lower initial UV-254 absorbance values and higher alkalinities. In a number of cases, ferric salts outperformed aluminum salts at reducing the DBP formation potential. Redox potential measurements were added to the list of analyses to determine trends and the feasibility of using this parameter as an additional indicator of process efficiency. It is expected that Eh will trend as the inverse of pH. However, this research presents that under constant pH conditions, the Eh readings seem to indicate the destabilization and stabilization processes expected during the coagulation step in drinking water treatment. Comparison of the Eh readings from the start of various treatment stages to the end provides some indication of the effectiveness the enhanced coagulation or enhanced softening process has on the removal of organic precursors for disinfection by-products.

Author: Justin Wassink
Publisher:
ISBN: 9780494765814
Category :
Languages : en
Pages : 300

View

Book Description
The formation of disinfection by-products (DBPs) in drinking water has become an issue of greater concern in recent years. Bench-scale jar tests were conducted on a surface water to evaluate the impact of enhanced coagulation on the removal of organic DBP precursors and the formation of trihalomethanes (THMs) and haloacetic acids (HAAs). The results of this testing indicate that enhanced coagulation practices can improve treated water quality without increasing coagulant dosage. The data generated were also used to develop artificial neural networks (ANNs) to predict THM and HAA formation. Testing of these models showed high correlations between the actual and predicted data. In addition, an experimental plan was developed to use ANNs for treatment optimization at the Peterborough pilot plant.

Author: Philip C. Singer
Publisher:
ISBN:
Category : Medical
Languages : en
Pages : 456

View

Book Description
Written by more than 30 DBP experts, this technical and managerial reference tool provides essential background and addresses recent activities of the EPA and environmental consultants. It answers important questions, such as how to balance microbial and chemical risks, and includes information on new regulation and treatment costs.

Author: Neeraj S. Pipada
Publisher:
ISBN:
Category : Drinking water
Languages : en
Pages : 94

View

Book Description
Both the proposed United States Environmental Protection Agency (USEPA) Disinfectants- Disinfection By-Products and Enhanced Surface Water Treatment rules have provisions for minimizing the formation of undesirable precursors of disinfection by-products (DBPs) in drinking water Natural Organic Matter (NOM) contains many of the precursors to the DBPs formed following disinfection of drinking water. DAX-8 resin procedures were used to isolate and fractionate NOM into six dissolved organic matter (DOM) fractions; Hydrophobic acid (FA), base (FB), neutral (FN), and hydrophilic acid (PA), base (PB) and neutral (PN). Aluminum sulfate (alum) jar coagulation tests were performed to determine the optimum coagulation ranges of each fraction. Different levels of pH, fraction concentrations, and coagulant levels were used in the experiments. Trihalomethane formation potential tests were performed on all the samples to check the removal of DBP precursors. Given the reactivities of the individual fractions to the formation of selected DBPs (i.e. trihalomethanes, halo acetonitriles, haloacetic acids), one can optimize on the removal of specific problematic fractions. Hence, if minimization of DBP formation was solely due to specific removal of precursors, microbial inactivation issues would be resolved due to the fact that CT may be increased without an increase in DBP formation.

Author:
Publisher: DIANE Publishing
ISBN: 142890249X
Category : Disinfection and disinfectants
Languages : en
Pages : 237

View

Book Description

Author: John Edward Goodwill
Publisher:
ISBN:
Category : Water
Languages : en
Pages : 496

View

Book Description

Author:
Publisher:
ISBN:
Category : Benchmarking (Management)
Languages : en
Pages : 196

View

Book Description