Advanced Wastewater Treatment Facility Research Articles

Fate of emerging contaminants in an advanced SBR wastewater treatment and reuse facility incorporating UF, RO, and UV processes

A critical factor for widescale water reuse adoption is the capability of advanced wastewater treatment facilities to consistently produce high-quality water by efficiently removing various pollutants, including emerging contaminants (ECs). This study monitored the fate of seventeen ECs (which included pesticides, antibiotics and other pharmaceutically active compounds) over six months in an advanced wastewater reuse facility situated in the United Arab Emirates. The facility integrates a sequencing batch reactor (SBR) based sewage treatment plant (STP) with a water recycling facility featuring ultrafiltration (UF), reverse osmosis (RO), and ultraviolet (UV) disinfection. ECs were detected and quantified at the influent and effluents of the various treatment stages, using an ultra-high-performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS). The STP exhibited variable removal efficiencies, achieving >90 % removal for compounds like caffeine and acetaminophen, while others, such as carbamazepine and thiabendazole, displayed poor removal (<10 %). UF treatment broadly resulted in limited removal, with ECs in permeate typically persisting in the 1–10 ng/L range. Subsequently, after undergoing RO treatment, eight ECs were still detected in the RO permeate, albeit at <1 ng/L, except for imidacloprid (2.5 ng/L). Conversely, the final UV disinfection step led to concentration increases of certain ECs, namely imidacloprid, thiabendazole, sulfamethoxazole, sulfamethazine and caffeine. Overall, the total EC concentration levels decreased considerably from 2300 ng/L in the STP influent to 5.2 ng/L in the RO permeate. However, a subsequent increase to 27.5 ng/L was observed after UV disinfection. While the study underscores the effectiveness of advanced treatment processes, notably RO, in reducing EC concentrations, it also demonstrates the importance of continuous EC monitoring in such facilities as many compounds persist post treatment. Additionally, the potential for processes like UV disinfection to increase certain EC concentrations highlights the need to optimize treatment trains to minimize EC concentration rebound.

Development of a fluorescence EEM-PARAFAC model for potable water reuse monitoring: Implications for inter-component protein–fulvic–humic interactions

Measuring the surrogate parameters total organic carbon and dissolved organic carbon (TOC/DOC) is not adequate, alone, to reveal nuances in organic character for optimizing treatment in potable water reuse. Alternatively, analyzing each organic compound contributing to the surrogate measurement is not possible. As an additional analytical tool applied between these extremes, the use of excitation-emission matrix fluorescence spectroscopy with PARAllel FACtor (EEM-PARAFAC) analysis was investigated in this research to track categories (components) or families of organic compounds during treatment in recycled water schemes. Although not all organic molecules fluoresce, many do, and fluorescence helps track their fate through water treatment processes. The sites investigated in this research were Lake Lanier, in Gwinnett County, Georgia, USA; the F. Wayne Hill Water Resources Center (FWH WRC) advanced wastewater treatment facility; and two pilot facilities operated in parallel representing the current indirect potable reuse (IPR) scheme as well as a pilot that evaluated direct potable reuse (DPR). A four-component nonnegativity PARAFAC model—elucidating protein-like (including tyrosine- and tryptophan-like fluorescence in a single component), soluble microbial product (SMP)-like, fulvic-like, and humic-like components—was fitted to the data. Each of the four components was spectrally and mathematically separated, implying that the fluorescing SMP-like component was not comprised of protein-, fulvic-, or humic-like components. PARAFAC excitation loadings with dual (double) pairs of fluorescing regions centered at the same emission wavelengths but different excitation wavelengths oriented parallel to the excitation axis and perpendicular to the emission axis were attributed to individual PARAFAC components. Significantly, the observation of PARAFAC emission loadings with multiple peaks—where the protein-like component exhibited fluorescence in both protein and fulvic/humic regions—is proposed to signify an intermolecular energy transfer (< 10 nm). Correct identification of EEM-PARAFAC components is fundamental to understanding water treatment.

Fluorescence excitation/emission matrices as a tool to monitor the removal of organic micropollutants from wastewater effluents by adsorption onto activated carbon

Monitoring the removal of organic micropollutants (OMPs) in advanced wastewater treatment facilities requires expensive and time-consuming analytical methods that cannot be installed online. Spectroscopic techniques such as fluorescence excitation/emission spectroscopy were demonstrated to offer the potential for monitoring OMPs removal in conventional wastewater treatment plants or ozonation pilots but their application to activated carbon (AC) adsorption processes was only investigated at lab scale and not in real treatment facilities. In this study, indexes from fluorescence emission/excitation matrices (EEMs) were used to find correlations with the removal of 28 OMPs from a large-scale AC pilot in fluidized bed employed for wastewater advanced treatment, as well as from batch experiments. Differences in OMPs removal could be observed depending on the operational conditions (i.e. pilot or batch experiments, contact time, type of AC) and the physico-chemical properties of the molecules. 7 PARAFAC components were derived from the fluorescence EEMs of 60 samples obtained before and after adsorption. Positive correlations were obtained between the removal of fluorescence indexes and most OMPs, and correlation coefficients were much higher than the ones obtained with UV254, confirming the interesting potential of fluorescence spectroscopy to accurately monitor adsorption performances at the industrial scale. The highest correlation coefficients were obtained for OMPs having the best removals while the ones that were refractory to adsorption, as well as to interactions with DOM, exhibited weak correlations. These results suggest that interactions between OMPs and fluorescing DOM and their subsequent co-adsorption onto AC were at the origin of the correlations found. Lower correlations were also found for the most biodegradable OMPs, which indicated that the occurrence of biological effects could make the monitoring of these compounds more challenging.

Evaluation of the Coupling of a Hybrid Power Plant with a Water Generation System

This paper presents the design and analysis of an energy/water system that combines a 20 MW hybrid concentrated solar/biomass power plant with an advanced wastewater treatment facility. Designed to be installed in one of the most demanding areas of the Iberian Peninsula, the Spanish region of Andalusia, this plant seeks to provide the area with potable water and electricity. The solar block works with a mixture of molten salts, while the biomass backup system of the power plant uses olive pomace. The implementation of a direct potable reuse facility further enhances the sustainability of the project. Urban sewage from the region is collected and passed through a series of purification procedures in order to generate potable water ready to be directly blended into the water distribution system. A sensitivity analysis is conducted to determine the feasibility of the co-generation of electricity and water in the area. With a capacity factor of 85% and an annual operation of 7,446 hours, the hybrid solar/biomass power plant generates 148.92 GWh. Exergetic analyses have been realized for two extreme cases: exclusive use of the solar block and exclusive use of the biomass system. An overall plant exergetic efficiency of 15% is found when the solar block is used and an efficiency of 34% is calculated when the biomass support system is used. Following an economic analysis, a total investment of 211,526,000 € is required for the full implementation of the system with a resulting levelized cost of energy of 0.25 €/kWh. We find that the selling price of the generated potable water which makes the plant operation economically viable is found to be 14.61 €/m3. At present, this price seems relatively high in view of current conditions; yet it is expected to become more realistic under future heightened water scarcity conditions, especially in arid regions.

Pilot testing of direct and indirect potable water reuse using multi-stage ozone-biofiltration without reverse osmosis

Pilot testing of direct potable reuse (DPR) using multi-stage ozone and biological filtration as an alternative treatment train without reverse osmosis (RO) was investigated. This study examined four blending ratios of advanced treated reclaimed water from the F. Wayne Hill Water Resources Center (FWH WRC) in Gwinnett County, Georgia, combined with the existing drinking water treatment plant raw water supply, Lake Lanier, for potable water production. Baseline testing with 100 percent (%) Lake Lanier water was initially conducted; followed by testing blends of 15, 25, 50, and 100% reclaimed water from FWH WRC. Finished water quality from the DPR pilot was compared to drinking water standards, and emerging microbial and chemical contaminants were also evaluated. Results were benchmarked against a parallel indirect potable reuse (IPR) pilot receiving 100% of the raw water from Lake Lanier. Finished water quality from the DPR pilot at the 15% blend complied with the United States primary and secondary maximum contaminant levels (MCLs and SMCLs, respectively). However, exceedances of one or more MCLs or SMCLs were observed at higher blends. Importantly, reclaimed water from FWH WRC was of equal or better quality for all microbiological targets tested compared to Lake Lanier, indicating that a DPR scenario could lower acute risks from microbial pathogens compared to current practices. Finished water from the DPR pilot had no detections of microorganisms, even at the 100% FWH WRC effluent blend. Microbiological targets tested included heterotrophic plate counts, total and fecal coliforms, Escherichia coli, somatic and male-specific coliphage, Clostridium perfringens, Enterococci, Legionella, Cryptosporidium, and Giardia.There were water quality challenges, primarily associated with nitrate originating from incomplete denitrification and bromate formation from ozonation at the FWH WRC. These challenges highlight the importance of upstream process monitoring and control at the advanced wastewater treatment facility if DPR is considered.This research demonstrated that ozone with biological filtration could achieve potable water quality criteria, without the use of RO, in cases where nitrate is below the MCL of 10 mg nitrogen per liter and total dissolved solids are below the SMCL of 500 mg per liter.

ENVISIONing the LCA of a wastewater treatment plant

Abstract In today's sustainability market where there are several tools to rate and grade the ‘green’ level of modern day infrastructure, the multi-tiered credit rating system called Envision provides an holistic approach to tackle the issue. Developed by the Institute for Sustainable Infrastructure (ISI), Envision has around 60 sustainability credits to score points in order to reach a recognized level of achievement. Life cycle assessment (LCA) is another tool that is gaining industry-wide acceptance for assessing potential environmental impacts. LCA is recognized by Envision as a good way to assess several of the available credits in their system. An LCA performed for Blue Plains Advanced Wastewater Treatment Facility (AWTF), Washington, D.C., USA was used as an example case study to show how credits could be calculated for a used water treatment facility.

Dissolved organic nitrogen recalcitrance and bioavailable nitrogen quantification for effluents from advanced nitrogen removal wastewater treatment facilities

The objective of this study was to determine the composition of nitrogen (N) in the effluents of advanced N removal (ANR) wastewater treatment plants (WWTPs). This study also tested two different experimental protocols for determining dissolved N recalcitrance. An analysis of 15 effluent samples from five WWTPs, showed effluent concentrations and especially effluent composition varied greatly from one system to the other, with total nitrogen (TN) ranging between 1.05 and 8.10 mg L−1. Nitrate (NO3−) accounted for between 38 ± 32% of TN, and ammonium accounted for a further 29 ± 28%. All of these samples were dominated by dissolved inorganic nitrogen (DIN; NO3− + NH4+), and uptake experiments indicated the DIN fraction was as expected highly bioavailable. Dissolved organic N (DON) accounted for 20 ± 11% for the total dissolved N in these effluents, and uptake experiments indicated the bioavailability of this fraction varied between 27 ± 26% depending on the WWTP assessed. These results indicate near complete DIN removal should be the primary goal of ANR treatment systems. The comparison of bioavailable nitrogen (BAN) quantification protocols showed that the dissolved nitrogen uptake bioassay approach was clearly a more reliable way to determine BAN concentrations compared to the conventional cell yield protocol. Moreover, because the nitrogen uptake experiment was much more sensitive, this protocol made it easier to detect extrinsic factors (such as biological contamination or toxicity) that could affect the accuracy of these bioassays. Based on these results, we recommend the nitrogen uptake bioassay using filtered and autoclaved samples to quantify BAN concentrations. However, for effluent samples indicating toxicity, algal bioassays will not accurately quantify BAN.

Wastewater treatment facility upgrade uses combination of technologies to solve nutrient removal challenges

New regulations required the 7.5 ML/d North East River Advanced Wastewater Treatment Facility to upgrade to meet lower annual average effluent nitrogen and phosphorus limits. At the same time, facility planning was underway to expand the facility to 17.0 ML/d to accommodate planned growth in the service area. Following a pilot study to establish the performance capabilities of the existing process and a technology alternatives evaluation, a combination of a Carrousel® 5-stage oxidation ditches followed by a membrane filtration system was used to convert the facility to a membrane bioreactor. This combination of technologies is unique among the more than 300 facilities recently upgraded for nutrient removal in the Chesapeake Bay region. The new process went into service in late 2015 and has demonstrated the ability to meet effluent performance requirements for total nitrogen and total phosphorus.

Easy as A-B-A-C 1-2-3. Case Studies of Ammonia Based Aeration Control at Multiple Advanced Wastewater Treatment Facilities

Easy as A-B-A-C 1-2-3. Case Studies of Ammonia Based Aeration Control at Multiple Advanced Wastewater Treatment Facilities

Sources and transformations of anthropogenic nitrogen along an urban river–estuarine continuum

Abstract. Urbanization has altered the fate and transport of anthropogenic nitrogen (N) in rivers and estuaries globally. This study evaluates the capacity of an urbanizing river–estuarine continuum to transform N inputs from the world's largest advanced (e.g., phosphorus and biological N removal) wastewater treatment facility. Effluent samples and surface water were collected monthly along the Potomac River estuary from Washington D.C. to the Chesapeake Bay over a distance of 150 km. In conjunction with box model mass balances, nitrate stable isotopes and mixing models were used to trace the fate of urban wastewater nitrate. Nitrate concentrations and δ15N-NO3− values were higher down-estuary from the Blue Plains wastewater outfall in Washington D.C. (2.25 ± 0.62 mg L−1 and 25.7 ± 2.9 ‰, respectively) compared to upper-estuary concentrations (1.0 ± 0.2 mg L−1 and 9.3 ± 1.4 ‰, respectively). Nitrate concentration then decreased rapidly within 30 km down-estuary (to 0.8 ± 0.2 mg L−1), corresponding to an increase in organic nitrogen and dissolved organic carbon, suggesting biotic uptake and organic transformation. TN loads declined down-estuary (from an annual average of 48 000 ± 5000 kg day−1 at the sewage treatment plant outfall to 23 000 ± 13 000 kg day−1 at the estuary mouth), with the greatest percentage decrease during summer and fall. Annually, there was a 70 ± 31 % loss in wastewater NO3− along the estuary, and 28 ± 6 % of urban wastewater TN inputs were exported to the Chesapeake Bay, with the greatest contribution of wastewater TN loads during the spring. Our results suggest that biological transformations along the urban river–estuary continuum can significantly transform wastewater N inputs from major cities globally, and more work is necessary to evaluate the potential of organic nitrogen and carbon to contribute to eutrophication and hypoxia.

Mineralization Kinetics of Soluble Phosphorus and Soluble Organic Nitrogen in Advanced Nutrient Removal Effluents

Given the importance of the watershed protection plans, direct determination of phosphorus (P) mineralization kinetics in advanced wastewater treatment facility effluents is crucial for developing the most protective strategies for minimizing eutrophication in receiving surface waters. In this study, bioassays were used to determine the mineralization rate of dissolved P in effluents from a broad range of advanced nutrient removal technologies (MBR, traditional biological, tertiary membrane, Blue PRO™, etc.). Mineralization kinetics were described by a Gamma model and three first-order decay models. A traditional one-pool model correlated poorly with the experimental data (i.e., r2 = 0.73 ± 0.09), whereas two and three-pool models performed much better (i.e., r2 > 0.9). These models provided strong evidence for the existence of recalcitrant P in the effluents from these facilities. The Gamma model showed the mineralization of organic P followed a reactive continuum and further suggested the partitioning of P loads with different bioavailability levels should be accounted for the future modeling practices. Although the Gamma model should be considered a theoretically correct model, the results also suggested simpler two and three-pool models could provide similar fits depending on the effluents. This title belongs to WERF Research Report Series ISBN: 9781780407302 (eBook)

Characterization of the dissolved phosphorus uptake kinetics for the effluents from advanced nutrient removal processes

Given the importance of the watershed protection plans, direct determination of phosphorus (P) mineralization rates in advanced wastewater treatment facility effluents is crucial for developing the most protective strategies minimiz eutrophication in receiving surface waters. In this study, algal bioassays were used to determine the uptake rate of dissolved P in effluents from a broad range of advanced nutrient removal technologies (e.g., membrane biological reactor, traditional biological, tertiary membrane, Blue PRO™, etc.). Dissolved P uptake kinetics were fit to a gamma model and three first-order decay models. A traditional one-pool model correlated poorly with the experimental data (i.e., r2 = 0.73 ± 0.09), whereas two-pool model and three-pool models performed much better (i.e., r2 > 0.9). These models also provided strong evidence for the existence of recalcitrant P in the effluents from these tertiary facilities. The Gamma model showed the mineralization of organic P followed a reactive continuum and further suggested the partitioning of P loads with different bioavailability levels should be accounted for the future modeling practices. From a modeling perspective, the Gamma model should be considered to be the theoretically best model as it gave the most parsimonious fit to the data using the fewest terms. Our study suggested that the current Total Maximum Daily Load (TMDL) model could be easily modified with the updated mineralization kinetics, which should lead to both ecological and economic benefits.

Optimization of Biogas Utilization at the Durham Advanced Wastewater Treatment Facility, Clean Water Services, Tigard, OR

Optimization of Biogas Utilization at the Durham Advanced Wastewater Treatment Facility, Clean Water Services, Tigard, OR

Optimization of External Sugar Fermentation at the Rock Creek Advanced Wastewater Treatment Facility

Optimization of External Sugar Fermentation at the Rock Creek Advanced Wastewater Treatment Facility

Occurrence and fate of antibiotics in advanced wastewater treatment facilities and receiving rivers in Beijing, China

The occurrence and removal of 13 antibiotics were investigated in five wastewater treatment plants (WWTPs) with advanced wastewater treatment processes in Beijing, China. Most of the target antibiotics were detected in the secondary and tertiary effluents, with the concentrations of 4.8–1106.0 and 0.3–505.0 ng·L−1. Fluoroquinolone antibiotics showed relatively high concentrations in all samples (782–1814 ng·L−1). Different tertiary treatment processes showed discrepant antibiotics removal performances. Ozonation process was found more effective in removing target antibiotics compared to the coagulation-flocculation-sedimentation process and sand filtration process. Investigation of the target antibiotics in three typical urban rivers in Beijing was carried out to understand antibiotics occurrence in surface water environment. Eight antibiotics were detected in the studied rivers, with highest concentration of antibiotics in the river which was mainly replenished by reclaimed water. This study showed the necessity of employing more effective advanced treatment facilities to further reduce the discharge amount of antibiotics.

Assessment of human adenovirus removal by qPCR in an advanced water reclamation plant in Georgia, USA

To assess human adenoviruses (HAdVs) removal in an advanced wastewater treatment facility and compare two parallel tertiary treatment methods for the removal of HAdVs. Tangential flow ultrafiltration was used to concentrate the water samples, and HAdVs were precipitated by polyethylene glycol. HAdVs were detected only by TaqMan real-time PCR, and HAdV genotype was determined by DNA sequence. HAdVs were detected in 100% of primary clarification influent, secondary clarification effluent and granular media (GM) filtration effluent samples but only in 31·2% of membrane filtration (MF) effluent and 41·7% of final effluent (FE) samples, respectively. The average HAdVs loads were significantly reduced along the treatments but HAdVs were still present in FE. Comparison of two parallel treatments (GM vs MF) showed that MF was technically superior to GM for the removal of HAdVs. These findings indicate that adenoviruses are not completely removed by treatment processes. MF is a better treatment for removal of adenoviruses than GM filtration. Because only qPCR was used, the results only indicate the removal of adenovirus DNA and not the infectivity of viruses. Presence of HAdVs in FE by qPCR suggests a potential public health risk from exposure to the treated wastewater and using the FE for recreational or water reuse purposes should be cautious.

Optimizing Biotreatment: Integrated Process Models and Control Strategies

The overall objective of this research project is to develop and implement model-based control strategies for improving biological treatment and document the methodology, benefits, and effort required. The project phase documented in this report include performing a literature review, installing extensive instrumentation at a full-scale advanced wastewater treatment facility, and developing real-time, dynamic models for biological nutrient removal that are suitable for control.The literature review was published as a separate report entitled Model-Based Control: Literature Review and Primer. It provides a detailed description of model predictive control and examines case studies from the process industries and the environment utility industry.Considerable on-line analytical instrumentation was installed at the Stamford WPCA wastewater treatment plant where all the full-scale experimental work was performed. The instrumentation includes five ammonia, six nitrate/nitrite, one suspended solids, four dissolved oxygen, and two ORP analyzers. The analyzers have performed reliably and accurately with minimal periodic maintenance.Artificial neural network models were developed for the nitrification and denitrification processes. These models provide adequately accurate results for the purpose of control. However, additional field work will be required to collect data with sufficient variability to include the effects of some parameters known to affect the nitrification and denitrification processes.This title belongs to WERF Research Report Series.ISBN: 9781843393924 (eBook)

RO System Design in Advanced Wastewater Treatment Facilities

RO System Design in Advanced Wastewater Treatment Facilities

Dynamic and Steady State Modeling for the Design of the Enhanced Nutrient Removal Facility at the Blue Plains Advanced Wastewater Treatment Facility

Dynamic and Steady State Modeling for the Design of the Enhanced Nutrient Removal Facility at the Blue Plains Advanced Wastewater Treatment Facility

City of Lancaster, Pennsylvania Biosolids Management Solution: New Facilities, New Processing and New Disposal/Use

City of Lancaster, Pennsylvania Biosolids Management Solution: New Facilities, New Processing and New Disposal/UseThe City of Lancaster, Pennsylvania's advanced wastewater treatment facility (AWWTF) produces approximately 30,000 wet tons per year of dewatered wastewater solids. Up until recent months, the primary and secondary solids have been landfilled without any stabilization method.In 2004, the City selected CDM to develop a plan to stabilize solids to meet Pennsylvania Department of Environmental...Author(s)Elaine SistareMark GouldSourceProceedings of the Water Environment FederationSubjectSession 11 - Planning Case HistoriesDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2009ISSN1938-6478SICI1938-6478(20090101)2009:3L.706;1-DOI10.2175/193864709793846547Volume / Issue2009 / 3Content sourceResiduals and Biosolids ConferenceFirst / last page(s)706 - 722Copyright2009Word count465Subject keywordsBiofilterscrubberlime stabilizationbeneficial use