Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Desalination as a method to provide clean drinking water has become vital – particularly in a context where drought, water scarcity and rapid quality decrease of water bodies have become an undeniable reality. After more than half a century of membrane-based desalination, fouling and scaling is still a dominant challenge. In membrane technologies, in particular, fouling and scaling are a major issue with respect to design, operation, reliability of the technologies and cost. This textbook covers theory and practice and is intended for designers, operators, consultants, suppliers and students. Principles of ultra- and nanofiltration and reverse osmosis (RO) are discussed, enabling the reader to understand the link between design, operation and fouling and scaling. Fouling (particulate, organic -including algal bloom events, inorganic, and biofouling) and scaling are treated in detail, including parameters to determine fouling and scaling potential of feed waters. Principles of conventional and advanced pre-treatment processes are highlighted and their effect on preventing fouling and scaling. In addition, the process design of RO systems and the recent advances in seawater RO and emerging membrane-based processes for seawater desalination are presented.

Membrane treatment of source water of impaired quality by an integrated membrane system (IMS), such as microfiltration (MF) pretreatment followed by RO, represents the industry standard for drinking water augmentation projects. An alternative IMS involving NF membranes and ULPRO membranes in place of conventional RO membranes provides an opportunity for lower pressure/higher flux operating conditions and higher selectivity (e.g., targeting trace organics over monovalent salts).? The purpose of this study was to explore whether nanofiltration (NF) and ultra-low pressure reverse osmosis (ULPRO) membranes can consistently meet potable water quality requirements with respect to total organic carbon (TOC), total nitrogen, and regulated and unregulated trace organic compounds. The goals were also to determine whether or not operating characteristics of NF and ULPRO membranes (such as flux, fouling/scaling, and cleaning frequencies) are comparable to conventional thin-film composite RO membranes and operating feed pressure requirements are significantly lower than conventional RO.? This work involved the development and validation of a laboratory-scale membrane testing protocol to select viable membranes for pilot- and full-scale operation. This selection protocol balanced operational characteristics with product water quality and allowed for a pre-selection of potentially viable candidate membranes. Membranes considered for selection were characterized as thin-film composite polyamide membranes and included commercially available ULPRO and NF membrane products. Three candidate membranes were selected and each tested using a 70 L/min (18 gpm) membrane pilot skid for at least 1,300 hours on microfiltered feed water at two full-scale facilities. Findings of this study were compiled into a model framework to describe and predict the rejection of organic micropollutants during NF or RO treatment.

The purpose of this project was to perform a careful evaluation of the technical and economic feasibility of advanced oxidation processes (AOPs) for methyl tertiary butyl ether (MTBE) removal. Specifically, the first objective of this project was to identify and fill data gaps related to the implementation and operation of AOPs with respect to MTBE removal. The second objective was to select and optimize the design of the most promising AOP(s) as a function of water quality parameters. The third objective was to determine conceptual-level engineering costs for these selected AOPs. The AOP technologies that were evaluated as part of this study included ozone/peroxide, continuous wave UV/peroxide, pulsed UV/peroxide, and E beam. The AOP technologies were compared with treatment costs, qualitative factors (e.g., technology reliability, flexibility), and influent and treated water quality considerations. Based on the comparative analysis, it was concluded that all the AOP technologies that were evaluated in this study are capable of removing MTBE at 95% or higher efficiencies. Ozone/peroxide and continuous UV/peroxide appear to be the most feasible technologies for AOP treatment of MTBE in drinking water sources. Originally published by AwwaRF for its subscribers in 2003 ?

The California Department of Health Services has established a provisional action level of 4 ug/L for perchlorate in drinking water due to its toxicity. There are 14 states in the United States that have thus far confirmed perchlorate in ground or surface waters. Ongoing research is investigating other treatment technologies for perchlorate rejection, including biological degradation, ion exchange, and activated carbon. The major objectives of this project were to:? determine the removal/rejection of perchlorate (ClO4-) ion by high pressure membranes, including reverse osmosis (RO), nanofiltration (NF), and tight ultrafiltration (UF);?????????????? evaluate the effects of water quality parameters, pH, ionic strength (conductivity), and co-ions and counter-ions, on process performance; and?????????????? study membrane operating conditions (e.g., recovery) on perchlorate rejection and potential scaling. Water quality is a determining factor in applying high pressure membranes to perchlorate rejection. Effective rejection of perchlorate by RO, NF, and tight UF has been demonstrated according to two rejection mechanisms: steric (size) versus electrostatic (charge) exclusion.? Based on its size (hydrodynamic radius), perchlorate is selectively rejected over chloride through size exclusion; however, based on charge exclusion, sulfate is selectively rejected over perchlorate. Originally published by AwwaRF for its subscribers in 2003. This publication can also be purchased and downloaded via Pay Per View on Water Intelligence Online

The results from this research affirmed the fact that inactivation of microorganisms by chemical disinfectants is influenced by disinfection, microbial, and water quality factors and the various interactions between these factors. The results showed that for all disinfectants, temperature is a key parameter that influences disinfection efficiency. The effect of turbidity was generally of less importance than pH and temperature. The safety factors (1.5 to 2.0) that are applied in the USEPA Ct tables should be satisfactory to account for these effects, not to mention the additional safety factors that are employed during Ct calculations (Cresidual and t10). Research Partner: USEPA Originally published by AwwaRF for its subscribers in 2003 ? ? ? ? ?

In the past, relatively minor attention has been focused on DON despite observations that both low and high molecular weight molecules containing organic nitrogen (e.g., simple amino acids, peptides, algal-derived humic substances) have been implicated as precursors of DBPs such as trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), nitromethanes, and nitrosamines like nitrosodimethylamine (NDMA). Nitrogenous organic matter has also been implicated as membrane foulant material. Dissolved organic carbon (DOC) is usually used as the surrogate for natural organic matter (NOM); NOM contains various ratios of carbon, oxygen, hydrogen, nitrogen, sulfur, and trace metals. While information exists on NOM removal through DOC measurements, it is unclear if DON is distributed equally among different molecular weight fractions.? The project involved three phases. First, several pretreatment processes were evaluated to selectively remove inorganic nitrogen from samples, thus allowing more accurate and a potentially direct quantification of DON. Second, a survey of 28 water treatment plants was conducted during two different seasons to assess DON and related organic matter occurrence. Additional sampling of reclaimed wastewater systems was also conducted. Third, laboratory experiments were conducted with alum and cationic polymer coagulants, activated carbon, or disinfectants (free chlorine or monochloramine) to assess the ability to remove DON and understand its reactions with disinfectants. ?

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Disinfection By-Products in Water Treatment describes new government regulations related to disinfection by-products. It explains the formation of microorganism by-products during water treatment and the methods employed to control them.The book includes several chapters on chlorine by-products and discusses techniques for the removal of chloroform from drinking water. It also describes gamma radiation techniques for removing microorganic by-product precursors from natural waters and the removal of bromate from drinking water.

Desalination as a method to provide clean drinking water has become vital – particularly in a context where drought, water scarcity and rapid quality decrease of water bodies have become an undeniable reality. After more than half a century of membrane-based desalination, fouling and scaling is still a dominant challenge. In membrane technologies, in particular, fouling and scaling are a major issue with respect to design, operation, reliability of the technologies and cost. This textbook covers theory and practice and is intended for designers, operators, consultants, suppliers and students. Principles of ultra- and nanofiltration and reverse osmosis (RO) are discussed, enabling the reader to understand the link between design, operation and fouling and scaling. Fouling (particulate, organic -including algal bloom events, inorganic, and biofouling) and scaling are treated in detail, including parameters to determine fouling and scaling potential of feed waters. Principles of conventional and advanced pre-treatment processes are highlighted and their effect on preventing fouling and scaling. In addition, the process design of RO systems and the recent advances in seawater RO and emerging membrane-based processes for seawater desalination are presented.

Membrane treatment of source water of impaired quality by an integrated membrane system (IMS), such as microfiltration (MF) pretreatment followed by RO, represents the industry standard for drinking water augmentation projects. An alternative IMS involving NF membranes and ULPRO membranes in place of conventional RO membranes provides an opportunity for lower pressure/higher flux operating conditions and higher selectivity (e.g., targeting trace organics over monovalent salts).? The purpose of this study was to explore whether nanofiltration (NF) and ultra-low pressure reverse osmosis (ULPRO) membranes can consistently meet potable water quality requirements with respect to total organic carbon (TOC), total nitrogen, and regulated and unregulated trace organic compounds. The goals were also to determine whether or not operating characteristics of NF and ULPRO membranes (such as flux, fouling/scaling, and cleaning frequencies) are comparable to conventional thin-film composite RO membranes and operating feed pressure requirements are significantly lower than conventional RO.? This work involved the development and validation of a laboratory-scale membrane testing protocol to select viable membranes for pilot- and full-scale operation. This selection protocol balanced operational characteristics with product water quality and allowed for a pre-selection of potentially viable candidate membranes. Membranes considered for selection were characterized as thin-film composite polyamide membranes and included commercially available ULPRO and NF membrane products. Three candidate membranes were selected and each tested using a 70 L/min (18 gpm) membrane pilot skid for at least 1,300 hours on microfiltered feed water at two full-scale facilities. Findings of this study were compiled into a model framework to describe and predict the rejection of organic micropollutants during NF or RO treatment.

The purpose of this project was to perform a careful evaluation of the technical and economic feasibility of advanced oxidation processes (AOPs) for methyl tertiary butyl ether (MTBE) removal. Specifically, the first objective of this project was to identify and fill data gaps related to the implementation and operation of AOPs with respect to MTBE removal. The second objective was to select and optimize the design of the most promising AOP(s) as a function of water quality parameters. The third objective was to determine conceptual-level engineering costs for these selected AOPs. The AOP technologies that were evaluated as part of this study included ozone/peroxide, continuous wave UV/peroxide, pulsed UV/peroxide, and E beam. The AOP technologies were compared with treatment costs, qualitative factors (e.g., technology reliability, flexibility), and influent and treated water quality considerations. Based on the comparative analysis, it was concluded that all the AOP technologies that were evaluated in this study are capable of removing MTBE at 95% or higher efficiencies. Ozone/peroxide and continuous UV/peroxide appear to be the most feasible technologies for AOP treatment of MTBE in drinking water sources. Originally published by AwwaRF for its subscribers in 2003 ?

The California Department of Health Services has established a provisional action level of 4 ug/L for perchlorate in drinking water due to its toxicity. There are 14 states in the United States that have thus far confirmed perchlorate in ground or surface waters. Ongoing research is investigating other treatment technologies for perchlorate rejection, including biological degradation, ion exchange, and activated carbon. The major objectives of this project were to:? determine the removal/rejection of perchlorate (ClO4-) ion by high pressure membranes, including reverse osmosis (RO), nanofiltration (NF), and tight ultrafiltration (UF);?????????????? evaluate the effects of water quality parameters, pH, ionic strength (conductivity), and co-ions and counter-ions, on process performance; and?????????????? study membrane operating conditions (e.g., recovery) on perchlorate rejection and potential scaling. Water quality is a determining factor in applying high pressure membranes to perchlorate rejection. Effective rejection of perchlorate by RO, NF, and tight UF has been demonstrated according to two rejection mechanisms: steric (size) versus electrostatic (charge) exclusion.? Based on its size (hydrodynamic radius), perchlorate is selectively rejected over chloride through size exclusion; however, based on charge exclusion, sulfate is selectively rejected over perchlorate. Originally published by AwwaRF for its subscribers in 2003. This publication can also be purchased and downloaded via Pay Per View on Water Intelligence Online

The results from this research affirmed the fact that inactivation of microorganisms by chemical disinfectants is influenced by disinfection, microbial, and water quality factors and the various interactions between these factors. The results showed that for all disinfectants, temperature is a key parameter that influences disinfection efficiency. The effect of turbidity was generally of less importance than pH and temperature. The safety factors (1.5 to 2.0) that are applied in the USEPA Ct tables should be satisfactory to account for these effects, not to mention the additional safety factors that are employed during Ct calculations (Cresidual and t10). Research Partner: USEPA Originally published by AwwaRF for its subscribers in 2003 ? ? ? ? ?

In the past, relatively minor attention has been focused on DON despite observations that both low and high molecular weight molecules containing organic nitrogen (e.g., simple amino acids, peptides, algal-derived humic substances) have been implicated as precursors of DBPs such as trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), nitromethanes, and nitrosamines like nitrosodimethylamine (NDMA). Nitrogenous organic matter has also been implicated as membrane foulant material. Dissolved organic carbon (DOC) is usually used as the surrogate for natural organic matter (NOM); NOM contains various ratios of carbon, oxygen, hydrogen, nitrogen, sulfur, and trace metals. While information exists on NOM removal through DOC measurements, it is unclear if DON is distributed equally among different molecular weight fractions.? The project involved three phases. First, several pretreatment processes were evaluated to selectively remove inorganic nitrogen from samples, thus allowing more accurate and a potentially direct quantification of DON. Second, a survey of 28 water treatment plants was conducted during two different seasons to assess DON and related organic matter occurrence. Additional sampling of reclaimed wastewater systems was also conducted. Third, laboratory experiments were conducted with alum and cationic polymer coagulants, activated carbon, or disinfectants (free chlorine or monochloramine) to assess the ability to remove DON and understand its reactions with disinfectants. ?