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 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