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Using Fluorescence to Characterize Four Day Simulated Distribution System Trihalomethane Content in Florida Groundwaters
Title
Using Fluorescence to Characterize Four Day Simulated Distribution System Trihalomethane Content in Florida Groundwaters.
Creator
Ousley, Jonathan, Duranceau, Steven, Lee, Woo Hyoung, Sadmani, A H M Anwar, University of Central Florida
Abstract / Description
The United States Environmental Protection Agency (USEPA) regulates public water systems and has established limits for certain disinfection by products (DBPs) that have been linked to health effects, such as bladder cancer. The regulation of DBPs, specifically total trihalomethanes (TTHMs) and haloacetic acids (HAAs), have encouraged water treatment professionals to assess the type and amount of organic precursors in their supplies. Three of the more common water quality parameters that are...
Show moreThe United States Environmental Protection Agency (USEPA) regulates public water systems and has established limits for certain disinfection by products (DBPs) that have been linked to health effects, such as bladder cancer. The regulation of DBPs, specifically total trihalomethanes (TTHMs) and haloacetic acids (HAAs), have encouraged water treatment professionals to assess the type and amount of organic precursors in their supplies. Three of the more common water quality parameters that are monitored as DBP surrogates include dissolved organic carbon (DOC), ultraviolet absorbance (UV254), and specific ultraviolet absorbance (SUVA). Although DOC, UV254, and SUVA have been effectively correlated to DBP formation, efforts to correlate fluorescence excitation emission matrices (FEEM) to DBP formation remains limited within the drinking water community. In this research, a fluorescence regional integration (FRI) approach was used to compare FEEM with DOC, UV254, and SUVA as an alternative surrogate for characterizing TTHMs for groundwater sources located in south central Florida. To quantitatively evaluate FEEM, DOC, UV254, and SUVA as TTHM precursor surrogate parameters, a statistical correlation analysis was employed. Thirteen groundwater samples were collected from various Central Florida groundwater wells in Lake County, Polk County, and Palm Beach County, and analyzed for FEEM, DOC, UV254, and SUVA prior to determining the four-day TTHM concentration using a simulated distribution system dosing procedure. The FRI method was then used to quantify FEEM by dividing the three-dimensional matrix into five distinct regions, each representing a unique organic constituent. The volume under each region was determined and used for the correlation analysis.It was determined that a combinations of regions III and V of the FEEM possessed a strong linear correlation to four day TTHM content (R2 = 0.95) as compared to DOC (R2 = 0.906), UV254 (R2= 0.84), SUVA (R2 = 0.640), and the individual regions of the FEEM. However, DOC showed the strongest correlation when a second order polynomial regression was used (R2 = 0.937). Results for the individual regions of the FEEM revealed four day simulated TTHM correlation coefficients of 0.25, 0.62, 0.86, 0.74, and 0.88 for regions I through V respectively. These values indicated that a combination of regions III and V, which represent the fulvic and humic-like organic fractions detected by FEEM respectively, was the most accurate four day simulated TTHM precursor surrogate parameter based on the groundwater supplies tested. These results reveal that although DOC is still one of the strongest surrogate parameters to TTHM formation, fluorescence has also shown to also be a potentially strong surrogate for groundwaters. The implications of these results signify that fluorescence monitoring could be a viable method of measuring organic content in groundwaters once the technology further develops.
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Date Issued
2016
Identifier
CFE0006839, ucf:51782
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006839
Trihalomethane Removal and Re-Formation in Spray Aeration Processes Treating Disinfected Groundwater
Title
Trihalomethane Removal and Re-Formation in Spray Aeration Processes Treating Disinfected Groundwater.
Creator
Smith, Cassandra, Duranceau, Steven, Randall, Andrew, Lee, Woo Hyoung, University of Central Florida
Abstract / Description
Historically, chlorination has been widely utilized as a primary and secondary disinfectant in municipal water supplies. Although chlorine disinfection is effective in inactivating pathogenic microbes, the use of chlorine creates the unintentional formation of regulated chemicals. On January 4, 2006, the United States Environmental Protection Agency (EPA) promulgated the Stage 2 Disinfectants/Disinfection by-product rule (DBPR) that focuses on public health protection by limiting exposure to...
Show moreHistorically, chlorination has been widely utilized as a primary and secondary disinfectant in municipal water supplies. Although chlorine disinfection is effective in inactivating pathogenic microbes, the use of chlorine creates the unintentional formation of regulated chemicals. On January 4, 2006, the United States Environmental Protection Agency (EPA) promulgated the Stage 2 Disinfectants/Disinfection by-product rule (DBPR) that focuses on public health protection by limiting exposure to four trihalomethanes (THM) and five haloacetic acids (HAA5), formed when chlorine is used for microbial pathogen control. This thesis examines post-aeration TTHM formation when employing spray-aeration processes to remove semi-volatile TTHMs from chlorinated potable water supplies.A bench scale air stripping unit was designed, constructed and operated to evaluate spray aeration for the removal of the four regulated trihalomethane (THM) species from potable drinking water including bromodichloromethane, bromoform, dibromochloromethane, chloroform. The study was conducted using finished bulk water samples collected from two different water treatment facilities (WTFs) located in Oviedo and Babson Park, Florida. Both treatment plants treat groundwater; however, Oviedo's Mitchell Hammock WTF (MHWTF) supply wells contain dissolved organic carbon and bromide DBP precursors whereas the Babson Park WTF #2 (BPWTF2) supply well contains dissolved organic carbon DBP precursors but is absent of bromide precursor. Three treatment scenarios were studied to monitor impacts on total trihalomethane (TTHM) removal and post-treatment (post-aeration) TTHM formation potential, including 1) no treatment (non-aerated control samples), 2) spray aeration via specially fabricated GridBee(&)#174; nozzle for laboratory-scale applications, 3) spray aeration via a commercially available manufactured BETE(&)#174; nozzle used for full-scale applications. Select water quality parameters, chlorine residual, and total trihalomethane concentrations were monitored throughout the study. The GridBee(&)#174; spray nozzle resulted in TTHM removals ranging from 45.2 (&)#177; 3.3% for the BPWTF2 samples, and 37.7 (&)#177; 3.1% for the MHWTF samples. The BETE(&)#174; spray nozzle removed 54.7(&)#177;3.9% and 48.1(&)#177;6.6% of total trihalomethanes for the Babson Park and Mitchell Hammock WTF samples, respectively. The lower percent removals at the MHWTF are attributed to the detectable presence of bromide and subsequent formation of hypobromous acid in the samples. Post spray aeration TTHM formation potentials were monitored and it was found that the MHWTF experienced significantly higher formation potentials, once again due to the presence of hypobromous acid which led to increases in overall TTHM formation over time in comparison with the Babson Park WTF #2 TTHM formation samples. In addition, chlorine residuals were maintained post spray aeration treatment, and initial chlorine residual and trihalomethane concentrations did not significantly impact overall spray nozzle performance. Among other findings, it was concluded that spray nozzle aeration is a feasible option for the Babson Park WTF #2 for TTHM compliance. For Oviedo's Mitchell Hammock WTF spray aeration was successful in removing TTHMs, however it was not effective in maintaining DBP rule compliance due to the excessive nature of DBP formation in the water samples. This study was not intended to serve as an assessment of varying nozzle technologies; rather, the focus was on the application of spray aerators for TTHM removal and post-formation in drinking water systems.
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Date Issued
2015
Identifier
CFE0005715, ucf:50117
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005715
COMPARISON OF THM FORMATION DURING DISINFECTION: FERRATE VERSUS FREE CHLORINE FOR DIFFERENT SOURCE WATERS
Title
COMPARISON OF THM FORMATION DURING DISINFECTION: FERRATE VERSUS FREE CHLORINE FOR DIFFERENT SOURCE WATERS.
Creator
Mukattash, Adhem, Randall, Andrew, University of Central Florida
Abstract / Description
The objective of the study was to compare the trihalomethanes (THMs) produced from ferrate with hypochlorite and to determine how different the THM production would be for a given degree of disinfection (3 log reduction in Heterotrophic Plate Count (HPC)). Different water samples were collected from Lake Claire, Atlantic Ocean, and secondary effluent from an advanced wastewater treatment plant. THM formation was determined using a standard assay over 7 days at room temperature. In addition...
Show moreThe objective of the study was to compare the trihalomethanes (THMs) produced from ferrate with hypochlorite and to determine how different the THM production would be for a given degree of disinfection (3 log reduction in Heterotrophic Plate Count (HPC)). Different water samples were collected from Lake Claire, Atlantic Ocean, and secondary effluent from an advanced wastewater treatment plant. THM formation was determined using a standard assay over 7 days at room temperature. In addition samples were tested for Total Coliform Escherichia coli (TC/E.coli), and heterotrophic bacteria using HPC by spreadplating on R2A agar. Dissolved organic carbon (DOC) was measured as well. Dosages of 2, 5, and 10 ppm of hypochlorite and ferrate were used for Lake Claire and Atlantic Ocean water, while 1, 2, and 5 ppm dosages were used for wastewater treatment effluent. Ferrate resulted in 48.3% ± 11.2% less THM produced for the same level of disinfection (i.e. approximately 3 logs reduction in HPC). Oxidation of DOC was relatively small with a 6.1 to 11.6 % decrease in DOC being observed for ferrate doses from 2 to 10 mg/L. Free chlorine oxidation of DOC was negligible.
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Date Issued
2007
Identifier
CFE0001734, ucf:47324
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0001734
COMPARISON OF THE EFFECTIVENESS OF ALTERNATIVE FERRATE (VI) SYNTHESIS FORMULAS AS DISINFECTANTS FOR WASTEWATER AND RIVER WATER
Title
COMPARISON OF THE EFFECTIVENESS OF ALTERNATIVE FERRATE (VI) SYNTHESIS FORMULAS AS DISINFECTANTS FOR WASTEWATER AND RIVER WATER.
Creator
Ginart, Rachelle, Reinhart, Debra, University of Central Florida
Abstract / Description
Ferrate (VI) has been studied as an alternative chemical to disinfect water and wastewater in recent years. The disinfection effectiveness of two different wet oxidation ferrate (VI) synthesis formulas in wastewater and Econlockhatchee River water was evaluated. Ferrate (VI) is synthesized by addition of ferric chloride to a mixture of sodium hydroxide and calcium hypochlorite (refer to U.S. Patent 6,790,429). One ferrate (VI) synthesis formula uses below the stoichiometric requirement of...
Show moreFerrate (VI) has been studied as an alternative chemical to disinfect water and wastewater in recent years. The disinfection effectiveness of two different wet oxidation ferrate (VI) synthesis formulas in wastewater and Econlockhatchee River water was evaluated. Ferrate (VI) is synthesized by addition of ferric chloride to a mixture of sodium hydroxide and calcium hypochlorite (refer to U.S. Patent 6,790,429). One ferrate (VI) synthesis formula uses below the stoichiometric requirement of hypochlorite (Low Chlorine Formula) while the other ferrate (VI) synthesis formula uses more than the stoichiometric requirement of hypochlorite (Standard Chlorine Formula). For applications requiring low chlorine residual effluent quality, the Low Chlorine Formula intuitively is a more suitable disinfectant than the Standard Formula. For applications where chlorine residual is of little or no significance, the Standard Formula is logically a more suitable disinfectant due to lower production cost and production of higher ferrate (VI) concentrations than the Low Chlorine Formula. The total chlorine concentration, unfiltered and filtered ferrate (VI) concentration, and dissolved organic carbon concentration before and after treatment using both ferrate (VI) formulas in wastewater and Econ River water was measured at a contact time of 30 minutes. Disinfection capabilities were measured by comparing the quantity of Heterotrophic bacteria, Total Coliform, Escherichia coli, and Enterococcus bacteria pre-ferrate (VI) to post-ferrate (VI) at dosages of 2, 4, and 7.5 mg/L as ferrate (VI) using both ferrate (VI) formulas. The rate of disappearance of both ferrate (VI) formulas in wastewater at an unadjusted pH and pH of 6.0-6.35 was determined. In addition the total oxidant absorbance and total chlorine concentration were measured over a 30-minute period. Both ferrate (VI) formulas were effective at inactivating Total Coliform, E. Coli, Enterococcus, and heterotrophic bacteria at a 30-minute contact time and lowering DOC concentrations in Econlockhatchee River water and secondary wastewater. The Standard Formula demonstrated better disinfection at lower dosages than the Low Chlorine Formula. In both ferrate (VI) formulas, there was a presence of an instantaneous demand of ferrate (VI) and a first-order reaction rate of ferrate (VI) over 30 minutes. The chlorine residual of 7.5 mg/L ferrate (VI) dose in wastewater at a 30-minute contact time was 0.2 to 0.6 mg/L Cl2 for the Low Chlorine Formula and 0.8 to 1.4 mg/L Cl2 for the Standard Formula. These experiments indicate that both ferrate (VI) formulas can serve as effective environmentally friendly disinfectants for wastewater and Econ River water.
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Date Issued
2008
Identifier
CFE0002284, ucf:47843
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0002284
Disinfection By-Product Reduction Study of a Small Central Florida Public Water System
Title
Disinfection By-Product Reduction Study of a Small Central Florida Public Water System.
Creator
Staubus, Paul, Duranceau, Steven, Sadmani, A H M Anwar, Randall, Andrew, University of Central Florida
Abstract / Description
The disinfection of water for potabilization has proven to be one of the most significant public achievements of the 20th century. Although chemical disinfectants are successfully utilized to inactivate acute pathogenic organisms, they may react with natural organic matter (NOM) to produce potentially-harmful disinfection by-products (DBPs). As a result, the United States Environmental Protection Agency regulates DBPs such as total trihalomethanes (TTHMs) and haloacetic acids (HAAs). The...
Show moreThe disinfection of water for potabilization has proven to be one of the most significant public achievements of the 20th century. Although chemical disinfectants are successfully utilized to inactivate acute pathogenic organisms, they may react with natural organic matter (NOM) to produce potentially-harmful disinfection by-products (DBPs). As a result, the United States Environmental Protection Agency regulates DBPs such as total trihalomethanes (TTHMs) and haloacetic acids (HAAs). The research herein is focused on the formation, removal, and control of TTHMs and HAAs in a small public water system (PWS) in Polk County, Florida (County). Pilot-scale tests were implemented to determine the efficacy of stripping TTHMs using single-pass spray and recirculating tray aeration systems, both operating at flows of 3 gallons per minute. In the spray aerator evaluation, an average TTHM reduction of 29.5% was recorded. With tray aeration, a 46.7% reduction of TTHMs was observed after a single pass through the assembly. The benefits of additional recirculation appeared to decrease significantly after four passes, at a TTHM removal of 85.5%. A raw water blending effort was conducted to model bypass around granular activated carbon (GAC) adsorption vessels. The results demonstrated the feasibility of a 50% blend in full-scale treatment operations. With this blend, chlorine residuals and HAA concentrations were able to be controlled throughout 48 hours of incubation at 30(&)deg;C. From the data collected, a water quality plan was developed for the County's Waverly PWS. The plan to control the formation of DBPs integrated a recirculating tray aeration process for TTHM stripping complemented with GAC adsorption process for removing DBP precursors.The estimated conceptual operating cost was approximated at $24,000 annually. This cost considered carbon replacement as well as the recirculation pump operation. If the recommended 50% GAC bypass is applied, the conceptual operating cost reduces to approximately $15,250 annually.
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Date Issued
2018
Identifier
CFE0007249, ucf:52175
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007249
Investigating Novel Water Treatment Methods and Monitoring Techniques for Sulfide-Laden Groundwater Supplies
Title
Investigating Novel Water Treatment Methods and Monitoring Techniques for Sulfide-Laden Groundwater Supplies.
Creator
Yoakum, Benjamin, Duranceau, Steven, Lee, Woo Hyoung, Sadmani, A H M Anwar, Moore, Sean, University of Central Florida
Abstract / Description
This dissertation reports on research related to novel water treatment and monitoring techniques for sulfide-laden groundwater supplies. The dissertation is divided into several chapters with four core chapters focused on investigations studying a novel water treatment method or monitoring technique. The first investigation assessed the efficacy of multi-pass spray aeration treatment to remove trihalomethanes (THMs) and to reduce the total THM formation potential (TTHMFP) of an aerated water...
Show moreThis dissertation reports on research related to novel water treatment and monitoring techniques for sulfide-laden groundwater supplies. The dissertation is divided into several chapters with four core chapters focused on investigations studying a novel water treatment method or monitoring technique. The first investigation assessed the efficacy of multi-pass spray aeration treatment to remove trihalomethanes (THMs) and to reduce the total THM formation potential (TTHMFP) of an aerated water column post-aeration. A recirculating spray aeration pilot unit was constructed to make this assessment. To assess the effect of multi-pass spray aeration on the TTHMFP, water was recirculated through a fabricated spray nozzle for various lengths of time. Results showed that multi-pass spray aeration can remove chloroform, dichlorobromomethane, dibromochloromethane and bromoform to below detection levels ((<) 0.7 ppb) for the waters investigated. Additionally, spray aeration reduced the TTHMFP of chlorinated water. Results suggest multi-pass spray aeration may be a viable treatment option for some bromide container waters. Results also indicate that multi-pass spray aeration removes bromide from the bulk water in the form of organically bound volatile compounds.The second investigation assessed the efficacy of using pre-existing tray aeration infrastructure to comply with disinfection by-product (DBP) regulations. To assess the efficacy of tray aerators to reduce the concentration TTHMs a pilot tray aerator was constructed. Results showed that after five tray passes (each pass consisting of water being passed over five trays) the concentration of TTHMs was below the detection limit ((<) 0.7 ppb) for the water investigated. To assess the efficacy of tray aeration at full-scale, a water treatment plant and the distribution system it serves were monitored for eight months. Results showed an approximate 40 ppb reduction in the TTHM concentration at two on-site monitoring locations and the one off-site monitoring location (initial concentrations being approximately 54 ppb, 60 ppb and 73 ppb, respectively). Results suggest that the utility managing the full-scale system could comply with DBP regulations by using the pre-existing tray aeration infrastructure to reduce formed THMs on-site where regulated haloacetic acids are not predominant.The third investigation assessed the efficacy of using biological activated carbon (BAC) to remove disinfection by-product precursor matter to comply with DBP regulations. To research this method, a pilot scale BAC filter was operated for three independent test runs. In addition, two full-scale WTPs using BAC were monitored over time. Results showed an approximate 40 percent removal of dissolved organic carbon (DOC) during the three pilot runs and an approximate 55 percent removal of DOC during full-scale monitoring. Results showed that the reduction in DOC reduced the TTHMFP of BAC treated water. Results suggest that BAC treatment could be a viable treatment option to comply with DBP regulations in the sulfide-laden water studied.The fourth investigation assessed the suitability of oxidation reduction potential (ORP) to monitor the effectiveness of an oxidizing media filter used to remove sulfur from a sulfide-laden groundwater. Results showed that ORP was more useful as a measurement technique as compared to free chlorine residual when assessing filter bed health and regeneration effectiveness. It was determined that when the ORP measurement taken from within the oxidative media layer was below 500 mV, the filter bed was not providing treatment, and manganese could be released. Results showed a significant increase in turbidity ((>) 2 NTU) and total manganese ((>) 0.05 mg/L) occurred when the ORP within the filter bed dropped below 400 mV. More frequent cycling of the filters was found to be an effective treatment option to maintain ORP values above an identified 400 mV operational threshold.
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Date Issued
2017
Identifier
CFE0007141, ucf:52317
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007141