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Effect Of Wet Weather Driven Dissolved Oxygen Sags On Fishes In Urban Systems

by John R. Wolfe

45,05€ + 10% CARD

 Available as eBook only. <div><br></div><div>Waters in urbanized areas often experience hypoxic events due to combined sewer overflows and urban runoff. Low dissolved oxygen is believed to negatively affect biota in the receiving waters, yet many urban areas have rich and diverse fish species assemblages. </div><div><br></div><div>This study assesses the behavioral and physiological responses of urban fish to understand how they have adapted to hypoxia Largemouth bass from the Chicago Area Waterway System (CAWS) were studied using field telemetry and laboratory experiments. Fish movement in relation to dissolved oxygen levels was tracked using acoustic transmitters and dissolved oxygen transmitters, pioneering a new technique with the latter. While there was a reduction in the number of largemouth bass during hypoxia, the fish did not depart the areas entirely. Some fish remained in hypoxic areas, while others maintained ranges at the periphery of hypoxic areas. Oxygen shock trials, field sampling and Pcrit analyses of CAWS fish showed that the study fish were not in poor nutritional condition, they were not suffering from chronic stress, nor did they exhibit an enhanced (or reduced) tolerance to low dissolved oxygen when compared to fish in control populations. The study suggests a behavioral shift, reducing time in hypoxic zones, without apparent physiological costs/adjustments. </div>
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Guidelines For Utilities Wishing To Conduct Pilot-Scale Demonstrations

by Lori Stone e Wendell Khunjar

37,10€ + 10% CARD

 As stewards of public funds, Water Resource Recovery Facilities (WRRFs) can be conservative in their approach to new technologies and processes, which hinders the advancement of technology and limits beneficial returns. This reluctance can be overcome by reducing perceived complexity surrounding pilot-scale projects, and by demonstrating applicable technologies, costs, and logistics. Sharing and documenting the lessons learned from conducting demonstration projects can encourage utilities to consider new technologies and increase confidence in decision-making. WERF’s experience with utilities engaged in the Leaders Innovation Forum for Technology (LIFT) focus groups indicates that the utilities may be inexperienced with new technologies and unfamiliar with the steps required for a successful demonstration project that empowers the utility with enough information to make informed decisions on new technologies. This project will examine the perceived and real complexities in conducting demonstration studies by featuring industry-relevant examples to elevate understanding of technologies, performance expectations, and implementation processes.
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Database Of Permitting Practices For Seawater Concentrate Disposal

by Mike Mickley e Nikolay Voutchkov

37,10€ + 10% CARD

 Permitting the disposal of concentrate and other waste streams is often one of the most challenging tasks associated with the development and implementation of desalination projects. This study focuses on the review of key regulatory requirements, support studies, and permitting practices for medium and large seawater reverse osmosis (SWRO) desalination plants in the United States and abroad. The size range (from 2.5 to 110 MGD or 9.5 to 440 ML/d) covers most plants built since 2005. The study is based on permitting experience with recent SWRO projects and is focused on the regulatory issues and considerations associated with the most commonly used concentrate management method: discharge to surface water bodies. Issues specific to the permitting of thermal desalination plants are not addressed in the report because, although popular in the Middle East, thermal desalination has not found significant application in seawater desalination in the United States and most other developed countries.The formal project objective was to identify the discharge information that permitting agencies need and the decision-making process they go through to permit discharge methods in order to help desalination project proponents focus and expedite their permitting efforts.The project involved documenting SWRO discharge regulatory information and facility information for the United States and selected countries. In the United States, the National Pollutant Discharge Elimination System (NPDES) permit is the primary permit required for discharge to surface waters. Discussion focused on events, information, and issues associated with obtaining an NPDES-type permit. One of the key limiting factors in the construction of new seawater desalination plants is the availability of suitable conditions and locations for disposal of the high-salinity sidestream commonly referred to as concentrate or brine. Concentrate is generated as a by-product of the separation of the minerals from the source water used for desalination. This liquid stream contains in concentrated form most of the source water’s dissolved solids as well as some pretreatment additives (i.e., residual amounts of coagulants, flocculants, and antiscalants) and other chemicals, as well as microbial contaminants and particulates rejected by the reverse osmosis (RO) membranes. If chemical pretreatment is used, such as coagulants, antiscalants, polymers, or disinfectants, some or all of these chemicals may reach or may be disposed of along with the plant discharge concentrate. Chapter 1 of the report provides background and contextual information for the study including the relatively new interest and recent challenges associated with the permitting complexity of medium and large SWRO desalination plants in the United States.
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Guidelines For Engineered Storage For Direct Potable Reuse

by Andrew Salveson, Linda Macpherson e Shane A. Snyder

37,10€ + 10% CARD

 Direct potable reuse (DPR) is the planned introduction of recycled water either directly into a public water system or into a raw water supply immediately upstream of a water treatment plant. DPR has inherent risks that differ from treatment of traditional source waters and conventional indirect potable reuse (IPR). In particular, DPR is a more closely coupled system, in which there is less time to monitor process water quality and respond to water quality concerns. This study evaluates how to replace the environmental buffer with engineered storage, called the engineered storage buffer (ESB). The ESB is a storage basin that provides sufficient time to monitor and respond to water quality concerns, called the failure response time (FRT). The ESB can also be designed to provide a measure of redundant treatment at a relatively low cost. It is envisioned as a tool to monitor process performance as it pertains to acute contaminants, with the primary focus on pathogen removal. The ESB is not envisioned as a long-term monitoring approach that could allow for FRT for chronic contaminants that have long analytical turnaround times. This report details how to determine the size of ESB through the use of advanced monitoring technologies and an evaluation of the treatment benefits of a range of processes. It also examines the public’s perception of IPR, DPR, and the environmental buffer, using a novel animation and a targeted web-based survey.
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Emerging Energy Reducing Technologies For Desalination Applications

by Joseph Jacangelo

37,10€ + 10% CARD

 The purpose of this project was to independently evaluate two emerging desalination technologies that showed promise for at least 10 to 15% savings in specific energy consumption (SEC) during seawater desalination. Thin film nanocomposite (TFN) reverse osmosis (RO) membranes from LG-NanoH2O, LLC and semi-batch RO from Desalitech, LLC were selected for evaluation at the pilot scale. The significance of performing such a study was to independently test innovative technologies and ultimately to accelerate industry adaptation of recently developed commercial products by minimizing the time to widespread testing and application. The project consisted of two major phases: (1) literature review and (2) pilot-scale evaluation of TFN RO membranes and the semi-batch RO process. A comprehensive literature review was conducted to identify emerging desalination technologies with particular focus on energy minimization during seawater desalination. Pilot-scale evaluations of TFN RO membranes, Qfx400ES, Qfx365ES, and Qfx400R, were conducted at West Basin Municipal Water District’s Ocean Water Demonstration Facility using seawater from the Pacific Ocean. Thin film composite (TFC) RO membranes from DowFilmtec, SW30ULE, and SW30XLE were used for baseline data collection and comparison with TFN RO membranes. The SEC at various flux and feed water recoveries were evaluated for the model membranes. A pilot scale evaluation of the semi-batch RO process was conducted at Israel Aerospace Industries (IAI) facility in Tel Aviv, Israel. Pretreated water from the Ashkelon Desalination Plant was used as the feed water for the pilot-scale evaluation. TFC RO membranes (SW30HRLE) were harvested from the full-scale plant and utilized in the semi-batch RO system. In addition, TFN RO membranes (Qfx400ES) also were utilized in the semi-batch RO system and SEC was evaluated at various flux and recovery conditions.
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Genifuel Hydrothermal Processing Bench-Scale Technology Evaluation Report

by Philip Marrone

37,10€ + 10% CARD

 Hydrothermal Liquefaction (HTL) and Catalytic Hydrothermal Gasification (CHG) proof-of-concept bench-scale tests were performed to assess the potential of the Genifuel hydrothermal process technology for handling municipal wastewater sludge. HTL tests were conducted at 300-350?C and 2900 psig on three different feeds: primary sludge (11.9 wt% solids), secondary sludge (9.7 wt% solids), and post-digester sludge (also referred to as digested solids) (16.0 wt% solids). Corresponding CHG tests were conducted at 350?C and 2900 psig on the HTL aqueous phase product using a ruthenium based catalyst. A comprehensive analysis of all feed and effluent phases was also performed. Total mass and carbon balances closed to within ± 15% in all but one case. Biocrude yields from HTL tests were 37%, 25%, and 34% for primary sludge, secondary sludge, and digested solids feeds, respectively. The biocrude yields accounted for 59%, 39%, and 49% of the carbon in the feed for primary sludge, secondary sludge, and digested solids feeds, respectively. It should be noted that HTL test results for secondary sludge may have been affected by equipment problems. Biocrude composition and quality were comparable to that seen with biocrudes generated from algae feeds. CHG product gas consisted primarily of methane, with methane yields (relative to CHG input) on a carbon basis of 47%, 61%, and 64% for aqueous feeds that were the product of HTL tests with primary sludge, secondary sludge, and digested solids, respectively. Siloxane concentrations in the CHG product gas were below the detection limit and well below fuel input composition limits set by several engine manufacturers. Relative to that of the sludge feeds, the HTL-CHG process resulted in a reduction in chemical oxygen demand (COD) of greater than 99.9% and a reduction in residual solids for disposal of 94-99%. The test results, as a whole, support further long-term testing in a larger scale integrated system that is representative of what would be installed at a water resource recovery facility (WRRF) in order to fully assess the technical and economic viability of this technology for wastewater sludge treatment.
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Nutrient Speciation And Refractory Compounds In Water Quality Models

by David Clark

37,10€ + 10% CARD

 Water quality modeling efforts are designed to provide an understanding of watershed conditions to support management efforts that include control of point and nonpoint sources (NPS). Nitrogen (N) and phosphorus (P) speciation is an important area of nutrient research, both in terms of biodegradability in wastewater treatment and bioavailability in the water environment. Water quality modeling may not be reflecting all that is known about point source effluent N and P from treatment facilities that reduce the total amount of nutrients discharged and also change N and P speciation and reduce bioavailability. WERF research into advanced levels of nutrient removal treatment is revealing new information about N and P speciation and reduced bioavailability of the N and P remaining after advanced treatment.Many of the more sophisticated mechanistic water quality models have the ability to simulate N and P species, and to some degree reflect refractory organic nutrient inputs and their subsequent degradation. Selecting water quality models with the capability of simulating nutrient species, and gathering monitoring data to characterize nutrient species and refractory compounds, is important to support enhancements in modeling.
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Risks From Ebola Discharge From Hospitals To Sewer Workers

by Charles N. Haas, Kyle Bibby e Leonard Casson

37,10€ + 10% CARD

 Current World Health Organization and Centers for Disease Control and Prevention guidance for the disposal of liquid waste from patients undergoing treatment for Ebola virus disease at hospitals in the United States is to manage patient excreta as ordinary wastewater without pretreatment. The safety of non-disinfected disposal of Ebolavirus-contaminated liquid wastes and the efficacy of disinfection approaches are unknown, leading to concerns about the potential for Ebolavirus transmission to sewer workers. The goals of this research are twofold: 1) to assess a sewer worker’s potential risk of developing Ebola virus disease from inhalation exposure when performing standard occupational activities in a sewer line serving a hospital receiving Ebola patients where there is no pretreatment of the waste prior to discharge, and 2) to conduct a review of inactivation of Ebola and other highly infectious agents by various disinfectants.Results from the quantitative microbial risk assessment suggest that the potential risk that sewer workers face when operating in a wastewater collection system downstream from a hospital receiving Ebola patients warrants further attention, and that current authoritative guidance for Ebolavirus liquid waste disposal may be insufficiently protective of sewer worker safety. Results from the inactivation review suggest that the effectiveness of various disinfectants on inactivation of highly infectious agents potentially found in wastewater collection systems, especially enveloped viruses, is variable and requires further evaluation for disposal and disinfection recommendations.
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Identification Of The 'Active' Fraction And Metabolic Pathways In Trace Organic Contaminants Removal Using Stable Isotope Probing

by Kartik Chandran

37,10€ + 10% CARD

 The widespread presence of trace organic contaminants (TOrC), such as the endocrine disrupting compound bisphenol-A (BPA), has been cause for growing concern due to persistence in the environment and potential ecological impacts. Despite progress made in understanding the removal of TOrC in biological wastewater treatment processes, there is still a lack of consensus regarding the identity of microorganisms active in biodegradation and the exact removal mechanisms involved. This research aimed to develop a clear understanding of the microbial ‘active’ fraction in activated sludge which is responsible for the assimilation of a selected TOrC, BPA. Through the use of DNA stable isotope probing (DNA-SIP), BPA assimilating organisms were identified. This active fraction of BPA assimilation included bacteria related to Sphingobium spp., Sphingomonas spp., Pussilimonas spp., and Variovorax spp.. Results from this work also confirm that prior or time-course exposure to BPA as well as bioreactor process conditions influence microbial community structure and function. Added understanding of TOrC removal mechanisms could be derived through continued investigation into microbial functions associated with BPA removal.
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Next Generation Tools For Assessing Death And Decay Of Critical Wastewater Bacteria

by Amy Pruden

37,10€ + 10% CARD

 This work used a combination of traditional microbiological and molecular approaches and modeling to advance understanding of decay processes in wastewater treatment. The overall goal was to support improved design and quality control of nitrification and pathogen inactivation processes considerate of more precise estimates of decay parameters.Pathogen and indicator decay experiments were framed with respect to USPEA time-temperature requirements in biosolids. Non-specific molecular methods, such as ATP and live/dead staining, were informative in pure culture but were not suitable as a proxy for pathogen or indicator monitoring in sludge. Existing USEPA time-temperature Class A biosolid regulations are based on CFU; however, DNA persistence suggests that non-cultured microorganisms correspondingly persist. DNA-targeted monitoring holds promise for detection of intact cells in sludge, but more work is necessary to ascertain the viability and infectivity.AOB and NOB measured decay rates were lower than literature values and there was a decline in AOB decay rates at temperatures above 25°C under the conditions of this study. Reduced decay rates have the most impact under extreme conditions, such as high ammonia loading or low temperatures, where lower decay rates translate to higher active biomass concentrations, lower ammonia peaks, and reduced times without nitrification.
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Impact Of Advanced Oxidation Processes On The Composition And Biodegradability Of Soluble Organic Nutrients In Wastewater Effluents

37,10€ + 10% CARD

 The characteristics and bioavailability of wastewater derived "refractory" organic nutrients and their susceptibility to removal has drawn significant attention from both regulatory agencies and wastewater utilities. As suggested by recent studies, the bioavailability of effluent organic nutrients to algae is relatively high. This implies that discharge of effluent organic nutrients from water resource recovery facilities (WRRFs) may contribute to the eutrophication potential. Therefore, investigation into alternative technologies for organic nutrients transformation and reduction, and the mechanisms involved in those processes, is warranted with the ultimate goal of improved eutrophication control. Advanced oxidation processes (AOPs) have been shown to be capable of reducing the concentrations of soluble organic nutrients and converting specific nutrient-containing organic compounds into simpler or more biodegradable forms. The overall objective of this study was to investigate the impact of AOP treatments on the speciation and composition of soluble nutrients and consequently their biodegradability in wastewater effluents. Secondary or tertiary effluents from three selected wastewater treatment plants were collected. Each effluent was treated with three different AOPs, including low-pressure ultraviolet (UV) irradiation, hydrogen peroxide (H2O2), and a combination of UV and H2O2. Both untreated and AOP-treated effluents were subjected to a comprehensive analysis for wastewater characterization, nitrogen speciation analysis, phosphorus speciation analysis, and soluble organic nitrogen (SON) biodegradability assays.The AOP processes at the conditions applied did not lead to significant changes in the SON concentrations for the wastewater effluents examined. However, fingerprinting and quantification of the dissolved organic matter (DOM) in untreated and AOP treated samples using fluorescence spectroscopy combined with parallel factor analysis revealed changes in DOM pool composition with various AOP treatments. This suggests that there may also be changes in organic nutrients composition. Based on biodegradability assessments, AOP treatments likely changed the composition and biodegradability of the SON compounds in the effluents. The impact of AOP treatments on effluent biodegradable SON (BSON) varied depending on the effluent and the AOP treatment. The BSON concentration increased by 0.02-0.2 mg/L (4-47%) after AOP treatment in one effluent, while the concentration decreased by 0.12-0.14 mg/L (60-69%) in another sample. For the secondary effluent sample, release of ammonia (0.04-0.1 mg/L) was observed during 15-day BSON incubation period for those samples treated with H2O2 or UV/H2O2, suggesting that the AOP treatments might lead to oxidation of colloidal organic matter in the filtered effluent. Comparison of the results among the three different AOPs indicated that the combined UV/H2O2 treatment was more effective at oxidizing some of the organic or organically bound nutrients.The impact of AOP treatment on effluent soluble organic phosphorus (SOP) composition varied depending on the effluents. For two WRRFs, AOP treatment at the dose conditions applied led to a decrease in the SOP level and seemed to convert it into SAHP, indicating a possible increase in effluent soluble phosphorus bioavailability. Comparison of the results among the three different AOPs indicated that the combined UV/H2O2 treatment was more effective at oxidizing some of the organic or organically-bound P compounds into a more readily removable form than either UV or H2O2 alone. With the limited number of effluents evaluated and under the conditions applied in this study, AOP treatments did not seem to significantly increase the biodegradability of SON. Therefore the proposed SON removal via AOP followed by biological treatment does not seem to be promising. Further investigation with more effluents is needed. Economic or LCA analysis should be perfo...
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Assessment Of Technology Advancements For Future Energy Reduction

37,10€ + 10% CARD

 The wastewater industry is continuously seeking new technologies that will reduce the need for purchased energy and improve its ability to beneficially recover resources. In addition, within energy-positive technologies such as codigestion that have begun to see wide levels of deployment, there are continuing efforts to improve performance. This research reviews 18 specific technology areas in an effort to assess their current level of maturity, projected impact on sector-wide energy use, and potential opportunities for adoption. Based on input from researchers active in emerging technologies, mainstream shortcut nitrogen and pyrolysis/gasification appear to be the technology areas most likely to be adopted in the near term because these technologies are closest to being ready and the deployment timeline is estimated to be relatively short. Mainstream shortcut N removal and mainstream anaerobic treatment are expected to have the greatest impact on energy use in the wastewater sector in the near term. Increased fundamental understanding of anaerobic communities was cited as a crucial component of future advancements, both in new technologies and optimization of existing technologies such as anaerobic digestion. Refining new methods to accomplish real-time monitoring of anaerobic community system functions was seen as a crucial part of this research.
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Towards A Renewable Future: Assessing Resource Recovery As A Viable Treatment Alternative - Case Studies Of Facilities Employing Extractive Nutrient Recovery Technologies

by Ronald Latimer e Wendell Khunjar

37,10€ + 10% CARD

 Extractive nutrient recovery, defined as the production of chemical nutrient products devoid of significant organic matter, represents a complementary strategy for managing nutrients in multiple waste streams. In this option, energy and resources are used to accumulate and produce a chemical nutrient product that is recyclable and has a resale value that could potentially help offset operating costs while reducing nutrient production from raw materials for agricultural or other uses. This report (NTRY1R12b) presents a compilation of case studies of water resource recovery facilities (WRRFs) at various stages of implementation of extractive nutrient recovery technologies in the form of struvite crystallization. Of the 20 WRRFs identified in this report, six have implemented or are implementing a struvite crystallization facility and seven have performed desktop and/or pilot evaluations. Data from these thirteen utilities were used to develop the Tool for Evaluating Resource Recovery-Phosphorus (TERRY-Phosphorus), which was used to perform a conceptual level evaluation of implementing struvite recovery at seven other WRRFs.Data from the full-scale WRRFs that have implemented struvite recovery indicate that sidestream soluble phosphorus removals ranged from 80 to 90%, while ammonia removal ranged from 7 to 30%. Struvite production ranged from 64 to 421 metric tonnes per year and was found to be dependent on the site specific conditions and technology employed. Drivers for implementing nutrient recovery included reduction in supplemental carbon requirements for nitrogen removal, reduction in aeration requirements, reduction in biosolids production versus conventional treatment alternatives, reduction in costs associated with mitigating nuisance precipitate formation, benefits to sludge dewaterability, and benefits associated with manipulating the N and P content of the biosolids. Quantifying the economic and non-economic benefits of these drivers together with site specific factors can help drive the implementation of resource recovery systems at full-scale WRRFs.
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Technologies For Sidestream Nitrogen Removal

by Gregory Bowden, H.David Stensel e Ryujiro Tsuchihashi

37,10€ + 10% CARD

 Liquid streams ("reject water" or "sidestream") generated by the dewatering of digested solids generally contain high levels of ammonia and phosphorus. These liquids can be treated in separate or sidestream processes rather than being directly returned to the mainstream treatment process. Sidestream treatment processes can reduce overall energy and chemical costs and improve treatment reliability for biological nutrient removal facilities. Sidestream treatment processes can also be used for nutrient recovery and reuse. This document is a compilation of a broad range of biological and physiochemical treatment processes specifically for nitrogen removal and recovery from municipal sidestreams and ammonia-rich industrial wastewaters. The benefits of these technologies are described along with design approaches and full-scale plant experiences. Reuse of recovered ammonia in the form of aqueous ammonia and ammonium salts for industrial and agricultural applications is also discussed. Future research needs in sidestream nitrogen removal and recovery are identified and summarized.
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Towards A Renewable Future: Assessing Resource Recovery As A Viable Treatment Alternative - State Of The Science And Market Assessment

by Ronald Latimer e Wendell Khunjar

37,10€ + 10% CARD

 Extractive nutrient recovery, defined as the production of chemical nutrient products devoid of significant organic matter, represents a complementary strategy for managing nutrients in multiple waste streams. In this option, energy and resources are used to accumulate and produce a chemical nutrient product that is recyclable and has a resale value that could potentially help offset operating costs while reducing nutrient production from raw materials for agricultural or other uses. These products include a variety of nitrogen, phosphorus, and iron compounds; however, products like phosphorus-enriched biosolids are excluded from this current report.This report represents the state of the science review of extractive nutrient recovery technologies with a special emphasis on bridging the knowledge gap currently faced by utilities when considering nutrient recovery for nutrient management. A complementary interactive electronic technology summary matrix is also available. Based on the review of technology, it is proposed that extractive nutrient recovery will likely be most viable if employed within a three-step framework including accumulation, release, and extraction steps.At the time of this report (2015), phosphorus recovery in the form of struvite was the most established technology for facilitating extractive nutrient recovery at full-scale water resource recovery facilities (WRRFs). Nitrogen only recovery is also feasible but has not been implemented extensively at WRRFs. Taking this into account, it is estimated that the domestic wastewater treatment industry can optimistically bring between 100,000 and 210,000 metric tonnes of P2O5/yr (as struvite) and up to 220,000 metric tonnes N/yr to the fertilizer market. Using historical market data, this suggests that the wastewater treatment industry can optimistically meet between 2 and 5% of the total P2O5 fertilizer demand, between 30 and 100% of the specialty ornamental P2O5 fertilizer demand, up to 2% of the total N fertilizer demand, and between 30 and 194% of the specialty and ornamental N fertilizer demand. The corresponding estimated market price for the nutrient products (2012 U.S. dollars) is approximately U.S.$1.25 to 2.50 /kg of N and U.S.$5.80 to 7.50/kg of P.Strategies that could be used facilitate the implementation of struvite recovery and other extractive nutrient recovery technologies are provided. These strategies include performing a complete benefits analysis. This analysis should quantify reductions in supplemental carbon requirements, reduction in aeration requirements, reduction in biosolids production for nutrient recovery versus conventional alternative, reduction in costs associated with mitigating nuisance precipitate formation, impacts to sludge dewaterability, and benefits associated with manipulating the N and P content of the biosolids.
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Mainstream Deammonification

by Maureen O' Shaughnessy

37,10€ + 10% CARD

 The objective of this research was to investigate the feasibility of applying the deammonification concept, which is already highly successful and proven in sidestream configurations, in the mainstream treatment process. The deammonification process for nitrogen removal provides a more efficient biological pathway compared to traditional nitrification/ denitrification. The demonstrated advantages of applying deammonification to mainstream treatment include energy-neutral or even energy-positive wastewater treatment, reduction of aeration energy, and reduction in external carbon and alkalinity demands. Implementation of mainstream deammonification is compatible with existing wastewater infrastructure, often with minimal modifications. The successful application of full-plant deammonification could save wastewater utilities operations costs for aeration and external carbon costs in the life cycle. Through demonstration and conceptual application at collaborating utilities, this research develops an evaluation framework for implementing full-plant deammonification.Deammonification is a two-step biological process where ammonia-oxidizing bacteria (AOB) aerobically convert half of the ammonia present in the wastewater to nitrite. In the second step, anammox bacteria oxidize the ammonia using nitrite to produce nitrogen gas without the organic carbon substrate required for conventional heterotrophic denitrification. Deammonification requires significantly less oxygen and so less energy is needed for nitrogen removal. Deammonification requires no external carbon addition, eliminating chemical purchases such as methanol. Process configurations using mainstream deammonification maximize energy recovery by diverting more particulate organic carbon away from the nitrogen removal process and directing it toward anaerobic treatment from which methane can be captured. The implications of deammonification for sustainable, cost effective and energy positive wastewater treatment are extraordinary.The report discusses application of short-cut nitrogen removal which includes nitritation-denitritation, in which ammonia oxidation ends at the intermediate nitrite, with the mainstream deammonification pathway. Both short-cut nitrogen removal pathways result in savings in energy, carbon and alkalinity over conventional nitrification-dentrification. To be successful, short-cut nitrogen removal strategies require maximizing AOB activity, while preventing the establishment of the nitrite oxidizing bacteria (NOB) that oxidize nitrite to nitrate and this report introduces and develops concepts for NOB out-selection. To progress from nitritation-denitritaion to deammonification, the AOB activity must be controlled to oxidize only half of the influent ammonia to nitrite, and a method of retaining the slow-growing anammox bacteria must be implemented. The report presents a progressive pathway from conventional nitrification-dentrification to short-cut nitrogen removal and discusses a framework of conditions and drivers for implementation.The research concludes that mainstream deammonification can be achieved. It is possible for wastewater treatment plants to retrofit to short-cut nitrogen removal utilizing existing infrastructure, often with minor modifications. The research revealed key site-specific drivers for applying short-cut nitrogen removal technology.
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Phosphorus Analysis In Wastewater: Best Practices

by D. Scott Smith

37,10€ + 10% CARD

 Phosphorus monitoring at wastewater treatment plants is essential as phosphorus (as total phosphorus) is an important main constituent regulated in treatment plant effluents. Recent trends are towards increasingly lower phosphorus limits, requiring reliable lower and lower phosphorus measurements. There is a long history of P analysis in dilute matrices; i.e., river and lake water and best practices have been developed. These best practices for surface waters are reported herein. Potential issues in wastewater P analysis by colorimetry include, pH, proton to molybdenum ratio, color development time, and digestion method. Of equal importance are the QA/QC measurement protocols implemented by wastewater analysis labs; demonstrably well performing examples from Coeur d’Alene, Spokane, and the City of Las Vegas are presented. Total reactive phosphorus is an ambiguous analytical measurement because the quantitative results depend strongly on color development time. For low level analysis, long path lengths have advantages in more precisely resolving low concentrations. Replicate measurements are essential, especially for low level P samples, in order to capture the true value of the sample within variability.When dealing with low concentrations even a small absolute error is a large relative error; thus, replicate measurements are essential to estimate true concentrations for dilute phosphorus samples.
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Assessing The Impacts Of Pulp Loading From Non-Dispersible Materials On Downstream Sewer Systems

by John Pastore

37,10€ + 10% CARD

 This study subjected wipes from five different manufacturers to a variety of tests to determine if changes to their physical characteristics occur when introduced into a sewer system and what effect the shredded material (pulp) has on the downstream sewer. Shredded and non-shredded, wipes were used in the study utilizing specialized bench-scale testing and live sewer testing.Results from the benchmark testing and live sewer testing, within both local and regional sewer systems, indicate that the wipes used in the study were significantly reduced in size through shredding and the resulting pulp, while increasing in weight due to water absorption, does not appear to cause clogging in the downstream sewer lines or exhibit noticeable odors. The pulp recovered during live sewer testing was found to consist of individual pieces less than two square inches in size. A small amount of pulp was observed binding with other background material in the sewer when grease and hair were present. The results suggest that shredding of the wipes by a mechanical grinder can minimize impacts to the downstream sewer lines by reducing the size of the material. Recommended actions include: educating the public on what to flush down the toilet, implementing an effective fats, oils, and grease (FOG) program and employing mechanical grinders ahead of pumps, when clogging due to non-dispersible material becomes a problem.
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Current Energy Position Of New York State Wastewater Treatment Facilities

by Diane Nascimento, John Willis e Nancy Andrews

37,10€ + 10% CARD

 In 2008, the New York State Energy Research and Development Authority (NYSERDA) published the "Statewide Assessment of Energy Use by the Municipal Water and Wastewater Sector" documenting 2003/2004 energy use at New York State wastewater facilities. Since the publication of these data, interest in energy efficiency and energy generation has grown considerably. Survey data indicated that a third of the respondents had completed capital projects to reduce energy use, and 65 percent indicated that they have future energy projects planned. At the same time, regulatory and technology changes such as tighter nutrient limits have added to many plants’ electrical demands.This research assesses the magnitude of energy performance shifts over the past 10 years based on the net effect of efficiency gains, increased electrical production, and increased process equipment loads. In facilities larger than 75 mgd, an overall trend toward increased average electrical energy consumption was observed, with recent implementation of nutrient removal being the most significant factor in this trend. Small and medium-sized facilities (less than 75 mgd) appear to be slightly improving their energy performance based on analysis of biochemical oxygen demand (BOD)-normalized energy metrics (kilowatt-hours per pound of BOD). Water resource recovery facilities with more developed energy approaches in their organization were more likely to have completed capital projects, operational optimization, and building-related improvements to reduce energy use.
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Visual Decision Support Tool For Supporting Asset Management Performance, Risk, And Cost Analysis In Collaboration With Gwinnett County Department Of

by Bradley Jurkovac, David Kerr, Diogo Vitorino, Helena Alegre, Rita S. Brito e Sergio T. Coelho

37,10€ + 10% CARD

 Managing urban water infrastructures faces the challenge of jointly dealing with assets of diverse types, useful life, cost, ages and condition. Service quality and sustainability require sound long-term planning, well aligned with tactical and operational planning and management. In summary, the objective of an integrated approach to infrastructure asset management is to assist utilities in answering the following questions:Who are we at present, and what service do we deliver? What do we own? Where do we want to be in the long-term? How do we get there?The AWARE-P approach (www.aware-p.org) offers a coherent methodological framework and a valuable portfolio of software tools. It is designed to assist water supply and wastewater utility decision-makers in their analyses and planning processes. It is based on a Plan-Do-Check-Act process and is in accordance with the key principles of the International Standards Organization (ISO) 55000 standards on asset management. It is compatible with, and complementary to WERF’s SIMPLE framework. The software assists in strategic, tactical, and operational planning, through a non-intrusive, web-based, collaborative environment where objectives and metrics drive IAM planning. It is aimed at industry professionals and managers, as well as at the consultants and technical experts that support them. It is easy to use and maximizes the value of information from multiple existing data sources, both in data-rich and data-stressed environments.This project aimed at testing, validating and tailoring the AWARE-P approach and software in the U.S. wastewater services context; developing new open-source software tools. The project produced:• A portfolio of tools for the Advanced Water Management and Rehabilitation-Portugal (AWARE-P) software validated at Gwinnett County Department of Water Resources (GCDWR), the main pilot case, and at two other U.S. cases, where a large amount of GIS and inspection data from a major utility, and GIS and operational data from a small utility were extensively explored;• A new, enhanced version of the tool to assess infrastructure value and support long-term re-investment policies; and• A new set of tools directed at data mining and condition-based inspection analysis and prediction.
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Evaluation Of Performance And Greenhouse Gas Emissions For Plants Achieving Low Phosphorus Effluents

by Christine De Barbadillo

37,10€ + 10% CARD

 This project was conducted under the WERF Nutrient Challenge program and included evaluation of operational practices and performance results for wastewater treatment plants designed to meet very low effluent total phosphorus (TP) concentrations. <div><br></div><div>As stringent phosphorus limits of 0.1 mg/L and lower are becoming more common, there is a need to better understand factors impacting the sustainability of operating to meet these limits. This effort focuses on maximizing what can be learned from existing facilities to help utilities operate more sustainably while achieving the necessary level of performance. </div><div><br></div><div>Eleven plants participated in this study. A number of these facilities had participated in earlier studies identifying phosphorus removal technologies and performance achieved and evaluating the reliability for achieving the needed effluent quality. Building upon this earlier work, each plant was assessed for its level of performance and operating practices associated with meeting low phosphorus limits. A carbon footprint calculation was developed to provide a comparison between facilities for greenhouse gas emissions associated with phosphorus removal operation. Several facilities also offered demonstration testing information and operating data to support an assessment of key issues that impact sustainable operation.</div>
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Wwtp Design And Operation Modifications To Improve Management Of Biosolids Regrowth, Odors, And Sudden Increase In Indicator Organisms

by Ana Deletic, Matthew J. Higgins, Peter Krebs, Sudhir Murthy, T. Koegst, Thammarat Koottatep e Tim Fletcher

37,10€ + 10% CARD

 Available as eBook only <div><br></div><div>The overall goal of this project was develop approaches to manage the issues of regrowth, odors, and sudden increase (ROSI) of indicator and pathogenic bacteria in biosolids. </div><div><br></div><div>The project entailed two phases. The first phase was focused on filling critical research gaps that provided the fundamental insights for developing solutions to these issues which includes method development. The second phase focused on developing and implementing solutions in the field. </div><div><br></div><div>The hypothesis that sudden increase is a result of incomplete inactivation of indicators was supported by the results from this work. The results suggest that Method 1680 underestimates the viable density of indicators in samples after thermal treatment. In addition, that results showed that to achieve complete inactivation of indicators, a slightly higher time-temperature regime will be needed and this new "best practices" time-temperature curve has been developed as part of the work. It should be emphasized that the current EPA time-temperature requirements appear to be sufficient for <i>Salmonella</i>, the bacterial pathogen used in the regulations. Several processes that utilize temperature about 75°C were able to eliminate SI. Gas chromatography-olfactometry was used to identify the persistent/long term odorants in centrifuged biosolids. The main persistent odorants contributing to cake odors were indole, skatole, p-cresol, and butyric acid. Interestingly, all of these compounds are breakdown products of organics such as proteins, carbohydrates and fats, suggesting that processes which eliminate these precursors will help reduce odors in biosolids. Odor panel results showed that the level of odors measured after longer term storage, was correlated to the shorter term TVOSC concentrations. Mechanistically this was expected since the short term TVOSCs and longer term odorants are produced by similar pathways. </div><div><br></div><div>Several amendments added to centrifuge cake were able to significantly reduce odors and/or regrowth. The incubation of anaerobically digested biosolids with protein degrading enzymes resulted in additional gas production as well as a reduction in odors after dewatering. Also, better digestion was associated with lower odors, and primary sludges produced greater odors compared to secondary sludges.</div>
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Developing A Standardized Protocol For Assessing The Biodegradability Of Trace Organic Contaminants

by Werf

44,52€ + 10% CARD

 This work was performed to better understand the factors that impact trace organic compound (TOrC) biodegradation kinetics in mixed microbial cultures. To accomplish this goal, optimized short-term batch tests using TOrC and identified TOrC surrogates were conducted using lab-scale activated sludge cultures. In these optimization experiments, the initial TOrC/surrogate concentration, readily biodegradable carbon concentration (rbCOD) and dissolved oxygen (DO) concentrations were varied. Once developed, these batch tests were deployed at three full-scale wastewater treatment facilities to estimate in-situ biotransformation kinetics. <div><br></div><div>This work confirms that TOrC biotransformation is best described using pseudo-first order kinetics. In contrast, results from surrogate experiments indicate that the current approach to aerobic respirometry is not sufficiently sensitive for resolving TOrC biotransformation versus endogenous respiration. Results from short-term batch test optimization also indicate that parameters estimated from depletion tests performed at artificially high TOrC concentrations are statistically similar to parameters estimated at low TOrC concentrations. This suggests that interrogation of the biomass can be performed at high TOrC concentrations, which would reduce the cost of sample processes associated with working at lower concentrations. </div><div><br></div><div>It was also found that the presence of excess readily biodegradable substrates suppress biotransformation rates for specific TOrC under aerobic and anoxic conditions. These results indicate that accurate estimation of biotransformation parameters requires careful design of the batch test to match the in-situ carbon conditions. An initial attempt to incorporate existing biotransformation and sorption parameters into current activated sludge process models was also performed. Results from this simulation indicate that modeling results are highly sensitive to the processes of sorption and desorption.</div>
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Best Practices For Sustainable Wastewater Treatment - Initial Case Study Incorporating European Experience And Evaluation Tool Concept

by George V. Crawford

158,99€ + 10% CARD

 The primary goal of the Optimization Challenge is to develop an approach that will allow the wastewater sector to achieve treatment goals while reducing the resources expended by 20% or more. The greater energy and chemical demands of facilities that provide nutrient removal make them a particularly challenging target, yet one with a significant potential return. This report has three objectives: To evaluate the European Experience with energy reduction and best practices at wastewater treatment plants (WWTPs). To evaluate the best practices employed at a European WWTP exhibiting significant energy reductions and energy management. To develop a viable template for a mass and energy balance model to be used as the basis for a subscriber-accessible tool that will be developed later. The project team considered European facilities that have a history of process optimization and could serve as examples of best practices for the industry. One of these is the Strass im Zillertal WWTP near Innsbruck, Austria, a municipal facility that provides for both nitrogen and phosphorus removal. A lengthy optimization process spanning more than a decade has enabled the Strass plant to attain the singular goal of producing more electricity on an annual basis than it consumes. Factors specific to the plant contributed to the Strass WWTP’s transformation into a net electricity producer, including the facility’s need for only low level (5 meter static head) influent pumping. However, the bulk of the energy and process optimization resulted from a combination of national programs, concerted efforts by a highly-educated operations team, and an energy-conscious mindset. WERF and its subscribers can readily apply these success factors to North American facilities. This study examined the context, drivers, and decisions behind the Strass WWTP enhancements toward energy self-sufficiency. These included: Examining regional and national energy and resource conservation programs that target wastewater treatment facilities in Scandinavia, Holland, Germany, Switzerland, and Austria. Assessing Energy Conservation manuals used to promote resource conservation in European WWTPs. Defining metrics applicable to WWTP operations optimization. Evaluating Strass WWTP performance, including interviews with the plant operations staff. Formalizing and extending the approaches used by the Strass team to quantify and evaluate the sustainability of treatment plant operations, and developing an approach to adapt them to the North American reality.
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