WorldWideScience

Sample records for repair sewer cleaning

  1. ANFIS-based approach for predicting sediment transport in clean sewer

    Science.gov (United States)

    Azamathulla, H. Md.; Ab. Ghani, Aminuddin; Fei, Seow Yen

    2012-01-01

    The necessity of sewers to carry sediment has been recognized for many years. Typically, old sewage systems were designated based on self-cleansing concept where there is no deposition in sewer. These codes were applicable to non-cohesive sediments (typically storm sewers). This study presents adaptive neuro-fuzzy inference system (ANFIS), which is a combination of neural network and fuzzy logic, as an alternative approach to predict the functional relationships of sediment transport in sewer pipe systems. The proposed relationship can be applied to different boundaries with partially full flow. The present ANFIS approach gives satisfactory results (r2 = 0.98 and RMSE = 0.002431) compared to the existing predictor. PMID:22389640

  2. Full factorial DOE to determine the influence of the process parameters in cleaning water jets used in sewer cleaning

    OpenAIRE

    Medan Nicolae; Lobontiu Mircea; Banica Mihai

    2017-01-01

    Industrial cleaning is a classic application of water jets technology. In the late 1950s, when reliable high pressure pumps were built, the usage of water jets spread widely in the field of pipes and sewerage cleaning. In our particular case, water jets using pressure between 100 and 200 bars are being used. The operational behaviour of these systems is dependent on the process parameters, which can vary, causing variations in the impact force. The experiment consists in the research method u...

  3. Full factorial DOE to determine the influence of the process parameters in cleaning water jets used in sewer cleaning

    Directory of Open Access Journals (Sweden)

    Medan Nicolae

    2017-01-01

    Full Text Available Industrial cleaning is a classic application of water jets technology. In the late 1950s, when reliable high pressure pumps were built, the usage of water jets spread widely in the field of pipes and sewerage cleaning. In our particular case, water jets using pressure between 100 and 200 bars are being used. The operational behaviour of these systems is dependent on the process parameters, which can vary, causing variations in the impact force. The experiment consists in the research method used in the study of the impact forces that occur in the sewerage cleaning head system. To determine the influence process parameters have on impact forces, the full factorial method was used. In order to measure the impact forces between the water jet and a flat and rigid surface, a stand was designed and built for generating pressure water jets, as well as a device to measure the impact forces.

  4. Taguchi versus Full Factorial Design to Determine the Influence of Process Parameters on the Impact Forces Produced by Water Jets Used in Sewer Cleaning

    Science.gov (United States)

    Medan, N.; Banica, M.

    2016-11-01

    The regular cleaning of the materials deposed in sewer networks is realized, especially with equipment that uses high pressure water jets. The functioning of this equipment is dependent on certain process parameters that can vary, causing variations of the impact forces. The impact force directly affects the cleaning of sewer systems. In order to determine the influence of the process parameters on the impact forces produced by water jets the method of research used is the experiment. The research methods used is that Taguchi design and full factorial design. For the experimental determination of the impact forces a stand for generating water jets and a device for measuring the forces of impact are used. The processing of data is carried out using the Software Minitab 17.

  5. Sewer Processes

    DEFF Research Database (Denmark)

    Hvitved-Jacobsen, Thorkild; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    by hydrogen sulfide and other volatile organic compounds, as well as other potential health issues, have caused environmental concerns to rise. Reflecting the most current developments, Sewer Processes: Microbial and Chemical Process Engineering of Sewer Networks, Second Edition, offers the reader updated...... revisions of chapters from the previous edition, adds three new chapters, and presents extensive study questions. • Presents new modeling tools for the design and operation of sewer networks • Establishes sewer processes as a key element in preserving water quality • Includes greatly expanded coverage...... of odor formation and prediction • Details the WATS sewer process model • Highlights the importance of aerobic, anoxic, and anaerobic processes Sewer Processes: Microbial and Chemical Process Engineering of Sewer Networks, Second Edition, provides a basis for up-to-date understanding and modeling of sewer...

  6. Sewer Processes

    DEFF Research Database (Denmark)

    Hvitved-Jacobsen, Thorkild; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    and valuable information on the sewer as a chemical and biological reactor. It focuses on how to predict critical impacts and control adverse effects. It also provides an integrated description of sewer processes in modeling terms. This second edition is full of illustrative examples and figures, includes...... microbial and chemical processes and demonstrates how this knowledge can be applied for the design, operation, and the maintenance of wastewater collection systems. The authors add chemical and microbial dimensions to the design and management of sewer networks with an overall aim of improved sustainability...... by hydrogen sulfide and other volatile organic compounds, as well as other potential health issues, have caused environmental concerns to rise. Reflecting the most current developments, Sewer Processes: Microbial and Chemical Process Engineering of Sewer Networks, Second Edition, offers the reader updated...

  7. Outcome following nerve repair of high isolated clean sharp injuries of the ulnar nerve.

    Directory of Open Access Journals (Sweden)

    René Post

    Full Text Available OBJECTIVE: The detailed outcome of surgical repair of high isolated clean sharp (HICS ulnar nerve lesions has become relevant in view of the recent development of distal nerve transfer. Our goal was to determine the outcome of HICS ulnar nerve repair in order to create a basis for the optimal management of these lesions. METHODS: High ulnar nerve lesions are defined as localized in the area ranging from the proximal forearm to the axilla just distal to the branching of the medial cord of the brachial plexus. A meta-analysis of the literature concerning high ulnar nerve injuries was performed. Additionally, a retrospective study of the outcome of nerve repair of HICS ulnar nerve injuries at our institution was performed. The Rotterdam Intrinsic Hand Myometer and the Rosén-Lundborg protocol were used. RESULTS: The literature review identified 46 papers. Many articles presented outcomes of mixed lesion groups consisting of combined ulnar and median nerves, or the outcome of high and low level injuries was pooled. In addition, outcome was expressed using different scoring systems. 40 patients with HICS ulnar nerve lesions were found with sufficient data for further analysis. In our institution, 15 patients had nerve repair with a median interval between trauma and reconstruction of 17 days (range 0-516. The mean score of the motor and sensory domain of the Rosen's Scale instrument was 58% and 38% of the unaffected arm, respectively. Two-point discrimination never reached less then 12 mm. CONCLUSION: From the literature, it was not possible to draw a definitive conclusion on outcome of surgical repair of HICS ulnar nerve lesions. Detailed neurological function assessment of our own patients showed that some ulnar nerve function returned. Intrinsic muscle strength recovery was generally poor. Based on this study, one might cautiously argue that repair strategies of HICS ulnar nerve lesions need to be improved.

  8. 40 CFR 35.935-16 - Sewer use ordinance and evaluation/rehabilitation program.

    Science.gov (United States)

    2010-07-01

    .../rehabilitation program. 35.935-16 Section 35.935-16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...-Clean Water Act § 35.935-16 Sewer use ordinance and evaluation/rehabilitation program. (a) The grantee... sewer use ordinance, and the grantee is complying with the sewer system evaluation and...

  9. REMOTELY CONTROLLED SEWERS

    OpenAIRE

    2014-01-01

    The basics of remotely controlled sewers [1] are presented focusing on Leipzig Municipality’s sewer control project [2] located in Germany. The consequences of sewer surcharge events are outlined considering possible counter measures. The required data basis, the controllable sewer objects and their relevant control units are pointed out. The presentation is finished exposing the types of control network, possible control algorithms as well as important aspects regarding the decision for / ag...

  10. Sewer System Management Plan.

    Energy Technology Data Exchange (ETDEWEB)

    Holland, Robert C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    A Sewer System Management Plan (SSMP) is required by the State Water Resources Control Board (SWRCB) Order No. 2006-0003-DWQ Statewide General Waste Discharge Requirements (WDR) for Sanitary Sewer Systems (General Permit). DOE, National Nuclear Security Administration (NNSA), Sandia Field Office has filed a Notice of Intent to be covered under this General Permit. The General Permit requires a proactive approach to reduce the number and frequency of sanitary sewer overflows (SSOs) within the State. SSMPs must include provisions to provide proper and efficient management, operation, and maintenance of sanitary sewer systems and must contain a spill response plan.

  11. City sewer collectors biocorrosion

    Science.gov (United States)

    Ksiażek, Mariusz

    2014-12-01

    This paper presents the biocorrosion of city sewer collectors impregnated with special polymer sulphur binders, polymerized sulphur, which is applied as the industrial waste material. The city sewer collectors are settled with a colony of soil bacteria which have corrosive effects on its structure. Chemoautotrophic nitrifying bacteria utilize the residues of halites (carbamide) which migrate in the city sewer collectors, due to the damaged dampproofing of the roadway and produce nitrogen salts. Chemoorganotrophic bacteria utilize the traces of organic substrates and produce a number of organic acids (formic, acetic, propionic, citric, oxalic and other). The activity of microorganisms so enables the origination of primary and secondary salts which affect physical properties of concretes in city sewer collectors unfavourably.

  12. Sewer Systems and Climate Change

    NARCIS (Netherlands)

    Brandsma, T.

    1993-01-01

    In this article the impact of climate change on the overflows of sewer systems is assessed. The emphasis is on the overflows of combined sewer systems. The purpose is twofold: first, to obtain a first-order estimate of the impact of climate change on overflows of sewer systems; and second, to obtain

  13. Locations of Combined Sewer Overflow Outfalls

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer identifies the locations of Combined sewer overflow outfalls. Combined sewer systems are sewers that are designed to collect rainwater runoff,...

  14. DEP Reported Sanitary Sewer Overflows

    Data.gov (United States)

    Montgomery County of Maryland — Sanitary sewer overflows reported to the Department of Environmental Protection by the Washington Suburban Sanitary Commission or individuals in the County. Update...

  15. 75 FR 82072 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2010-12-29

    ... discharges from its combined sewer overflows (``CSOs'') violate the Clean Water Act because the discharge of... States and the State of Ohio v. Northeast Ohio Regional Sewer District, Civil Action No. 10-cv-02895 was... Water Act, 33 U.S.C. 1251 et seq., in connection with the Northeast Ohio Regional Sewer...

  16. 76 FR 45617 - Notice of Lodging of the Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2011-07-29

    ... failure to properly operate and maintain its Combined Sewer Collection System, which resulted in dry weather overflows and numerous basement backups in the homes of residents of Jersey City. Under the terms... construction projects aimed at repairing or replacing deteriorating sewers within its Combined Sewer...

  17. Sewer Systems and Climate Change

    OpenAIRE

    Brandsma, T.

    1993-01-01

    In this article the impact of climate change on the overflows of sewer systems is assessed. The emphasis is on the overflows of combined sewer systems. The purpose is twofold: first, to obtain a first-order estimate of the impact of climate change on overflows of sewer systems; and second, to obtain insight into the relevant meteorological variables that are important with respect to climate change. A reservoir model is used to assess the impact of climate change on several combinations of st...

  18. A model for methane production in sewers.

    Science.gov (United States)

    Chaosakul, Thitirat; Koottatep, Thammarat; Polprasert, Chongrak

    2014-09-19

    Most sewers in developing countries are combined sewers which receive stormwater and effluent from septic tanks or cesspools of households and buildings. Although the wastewater strength in these sewers is usually lower than those in developed countries, due to improper construction and maintenance, the hydraulic retention time (HRT) could be relatively long and resulting considerable greenhouse gas (GHG) production. This study proposed an empirical model to predict the quantity of methane production in gravity-flow sewers based on relevant parameters such as surface area to volume ratio (A/V) of sewer, hydraulic retention time (HRT) and wastewater temperature. The model was developed from field survey data of gravity-flow sewers located in a peri-urban area, central Thailand and validated with field data of a sewer system of the Gold Coast area, Queensland, Australia. Application of this model to improve construction and maintenance of gravity-flow sewers to minimize GHG production and reduce global warming is presented.

  19. Self-optimising control of sewer systems

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Montero-Castro, Ignacio; Mollerup, Ane Loft;

    The design of sewer system control is a complex task given the large size of the sewer networks, the transient dynamics of the water flows and the stochastic nature of rainfall. This contribution presents a generic methodology for the design of a self-optimising controller in sewer systems...... to design an optimising control strategy for a subcathcment area in Copenhagen....

  20. 78 FR 42108 - Notice of Extension to Public Comment Period for Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2013-07-15

    ... Florida Department of Environmental Protection v. Miami-Dade County, Civil Action No. 1:12-cv-24400-FAM..., rehabilitation, repair, and replacement work on force mains, sewer lines, manholes, and pumps, and rehabilitation... sewer maintenance and repair programs which EPA believes will dramatically reduce the incidence and...

  1. Corrosion and odor management in sewer systems.

    Science.gov (United States)

    Jiang, Guangming; Sun, Jing; Sharma, Keshab R; Yuan, Zhiguo

    2015-06-01

    Sewers emit hydrogen sulfide and various volatile organic sulfur and carbon compounds, which require control and mitigation. In the last 5-10 years, extensive research was conducted to optimize existing sulfide abatement technologies based on newly developed in-depth understanding of the in-sewer processes. Recent advances have also led to low-cost novel solutions targeting sewer biofilms. Online control has been demonstrated to greatly reduce the chemical usage. Dynamic models for both the water, air and solid (concrete) phases have been developed and used for the planning and maintenance of sewer systems. Existing technologies primarily focused on 'hotspots' in sewers. Future research should aim to achieve network-wide corrosion and emission control and management of sewers as an integrated component of an urban water system.

  2. Reducing pathogens in combined sewer overflows using performic acid.

    Science.gov (United States)

    Tondera, Katharina; Klaer, Kassandra; Koch, Christoph; Hamza, Ibrahim Ahmed; Pinnekamp, Johannes

    2016-10-01

    Combined sewer overflows contribute significantly to pathogen loads in surface water. Some chemical disinfectants such as chlorine have proved to reduce the levels of microorganisms even in complex matrices such as wastewater in combined sewer systems; however, some of them release toxic by-products into water bodies and increase costs of plant maintenance and repair. In this study, we determined if performic acid (PFA) disinfection units can be operated at decentralized treatment facilities and reduce bacteria, viruses, and protozoan parasites in combined sewer overflows (CSOs). The PFA dosing unit at the inflow of a CSO storage tank dosed a fixed flow volume into the inflowing stormwater and, thus, concentrations varied between approximately 12-24mgl(-1). The results showed a reduction of most hygienically relevant bacteria with mean removal efficiencies of 1.8log10 for Aeromonas spp. and 3.1log10 for E. coli. For viruses, however, reduction was only observed for somatic coliphages with 2.7log10. In this setting, PFA does not seem to be suitable to remove e.g. protozoan parasites such as Giardia lamblia. In terms of operation, dosing the substance is uncritical in decentralized facilities, but the PFA needs too much time to react with pathogens after being dosed into the overflow of CSO storage tanks and before dilution with surface water in most facilities.

  3. Locations of Combined Sewer Overflow Outfalls - US EPA Region 3

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer identifies the locations of Combined sewer overflow outfalls. Combined sewer systems are sewers that are designed to collect rainwater runoff,...

  4. The Sewer Research Station in Frejlev

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Hvitved-Jacobsen, T.

    This report for the 2000 activities at the sewer research station in Frejlev. Only few - if any - sewer monitoring stations like the one in Frejlev exist. Without no doubt the field data produced - especially the time series - in the course of time will serve as a unique basis for projects dealing...

  5. A Novel Model for Sewer Ventilation

    DEFF Research Database (Denmark)

    Fuglsang, Emil Dietz; Nielsen, Asbjørn Haaning; Vollertsen, Jes

    2013-01-01

    Based on the naturally occurring gas CO2 the dynamics of natural ventilation and gas flow was studied in an intercepting sewer receiving wastewater from a pressure main. A deterministic physiochemical model including description of release of CO2 into the sewer gas phase was built and validated a...... against field measurements....

  6. Information use in Dutch sewer assest management

    NARCIS (Netherlands)

    Van Riel, W.A.P.; Langeveld, J.G.; Herder, P.M.; Clemens, F.H.L.R.

    2012-01-01

    Sewer systems are capital-intensive infrastructures, requiring appropriate asset management to safeguard serviceability. In the Netherlands, effective sewer asset management is described by De Leeuw’s control paradigm. Reliable data and information are key elements in decision-making for rehabilitat

  7. The Sewer Research Station in Frejlev

    DEFF Research Database (Denmark)

    Hvitved-Jacobsen, Thorkild; Schaarup-Jensen, Kjeld

    2003-01-01

    This report for the 1999 activities at the sewer research station in Frejlev. Only few - if any - sewer monitoring stations like the one in Frejlev exist. Without no doubt the field data produced - especially the time series - in the course of time will serve as a unigue basis for projects dealing...

  8. In-place rehabilitation of process sewers

    Energy Technology Data Exchange (ETDEWEB)

    Arles, K.R.; Faller, C.C. [E.I. DuPont de Nemours and Co., Inc., Wilmington, DE (United States)

    1996-07-01

    The majority of petrochemical manufacturing facilities have thousands of feet of existing underground gravity sewers that convey the site`s industrial wastes to treatment facilities. The integrity of these sewer systems is a serious concern to owners. A potential consequence of leaks is soil and groundwater contamination. Prior to 1992, only two options were available to remedy this situation. The sewer systems could be replaced with either a new dual-walled, monitored underground pipe system via direct bury, or with an above ground pumped system. In 1992, Engineering, in conjunction with several trenchless technology vendors, developed and demonstrated modified relining systems that can rehabilitate existing sewers and result in monitored dual-walled gravity sewer systems. These proven systems have since been enhanced, upgraded, and installed at two operating facilities. With thorough sewer investigation and assessments, industry now has viable, cost effective options to rehabilitate underground chemical process sewers. These upgraded sewer systems provide the environmental security of monitored dual-walled pipe, enhanced flow characteristics, and retain accessibility for maintenance and inspections.

  9. Ventilation in Sewers Quantified by Measurements of CO2

    DEFF Research Database (Denmark)

    Fuglsang, Emil Dietz; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    2012-01-01

    H, alkalinity and sewer-air CO2 concentrations. An intercepting sewer was studied and an average sewer-air retention time of approximately 1.5-2.5 hours was found at CO2 levels around 4-6 times the natural background. Also an upstream sub-catchment was studied. In this part of the sewer system the level of CO2...

  10. Sulfide and methane production in sewer sediments.

    Science.gov (United States)

    Liu, Yiwen; Ni, Bing-Jie; Ganigué, Ramon; Werner, Ursula; Sharma, Keshab R; Yuan, Zhiguo

    2015-03-01

    Recent studies have demonstrated significant sulfide and methane production by sewer biofilms, particularly in rising mains. Sewer sediments in gravity sewers are also biologically active; however, their contribution to biological transformations in sewers is poorly understood at present. In this study, sediments collected from a gravity sewer were cultivated in a laboratory reactor fed with real wastewater for more than one year to obtain intact sediments. Batch test results show significant sulfide production with an average rate of 9.20 ± 0.39 g S/m(2)·d from the sediments, which is significantly higher than the areal rate of sewer biofilms. In contrast, the average methane production rate is 1.56 ± 0.14 g CH4/m(2)·d at 20 °C, which is comparable to the areal rate of sewer biofilms. These results clearly show that the contributions of sewer sediments to sulfide and methane production cannot be ignored when evaluating sewer emissions. Microsensor and pore water measurements of sulfide, sulfate and methane in the sediments, microbial profiling along the depth of the sediments and mathematical modelling reveal that sulfide production takes place near the sediment surface due to the limited penetration of sulfate. In comparison, methane production occurs in a much deeper zone below the surface likely due to the better penetration of soluble organic carbon. Modelling results illustrate the dependency of sulfide and methane productions on the bulk sulfate and soluble organic carbon concentrations can be well described with half-order kinetics.

  11. Model Predictive Control of Sewer Networks

    Science.gov (United States)

    Pedersen, Einar B.; Herbertsson, Hannes R.; Niemann, Henrik; Poulsen, Niels K.; Falk, Anne K. V.

    2017-01-01

    The developments in solutions for management of urban drainage are of vital importance, as the amount of sewer water from urban areas continues to increase due to the increase of the world’s population and the change in the climate conditions. How a sewer network is structured, monitored and controlled have thus become essential factors for effcient performance of waste water treatment plants. This paper examines methods for simplified modelling and controlling a sewer network. A practical approach to the problem is used by analysing simplified design model, which is based on the Barcelona benchmark model. Due to the inherent constraints the applied approach is based on Model Predictive Control.

  12. Model Predictive Control of Sewer Networks

    DEFF Research Database (Denmark)

    Pedersen, Einar B.; Herbertsson, Hannes R.; Niemann, Henrik;

    2016-01-01

    The developments in solutions for management of urban drainage are of vital importance, as the amount of sewer water from urban areas continues to increase due to the increase of the world’s population and the change in the climate conditions. How a sewer network is structured, monitored...... and controlled have thus become essential factors for efficient performance of waste water treatment plants. This paper examines methods for simplified modelling and controlling a sewer network. A practical approach to the problem is used by analysing simplified design model, which is based on the Barcelona...

  13. OPTIMAL OPERATIONAL CONTROL OF INTERCEPTOR SEWER SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper, a mathematical model was built up to solve the problem of optimal operational control by analysing the factors on an interceptor sewer system and a Fortran program was produced for this model. This paper shows that the optimal control states can be determined by working out the optimal flow rates by means of Linear Programming (LP). The result is very sensitive to interception points and the concentration weight coefficients over time. The result further highlights some practical applications for the existing sewer systems or the sewer systems under design.

  14. Solids separation efficiency of combined sewer overflows.

    Science.gov (United States)

    Luyckx, G; Vaes, G; Berlamont, J

    2005-01-01

    The removal of sewer solids at combined sewer overflow locations depends on the flow patterns inside the overflow structure on the one hand and on the sediment characteristics on the other hand. Flow conditions can be described by the residence time distribution; sewer sediments can be characterised by their settling velocity distribution. The combination of both distributions leads to a dimensionless efficiency curve, which gives the removal efficiency as a function of the Hazen number. For field conditions this efficiency curve is mainly influenced by the settling velocity distribution of the sewer sediments and, as a consequence, nearly identical efficiency curves are found for different types of prototype CSO structure. For design purposes, a methodology using return frequency analysis is proposed.

  15. The Effect of Converting Combined Sewer Catchments to Separate Sewer Catchments

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Rasmussen, Michael R.; Thorndahl, Søren Liedtke

    2011-01-01

    The overall objective of this paper is to contribute to the standing debate concerning the advantages of separate sewer systems compared to traditional combined sewers. By a case study this investigation reveals that a transformation of one fourth of a given total area from being combined to become...... separate sewer catchments decreases the amounts of storm water and pollutants diverted to the waste water treatment plant (WWTP) or as combined sewer overflows (CSO). But this happens at the expense of an increase in amounts of storm water and pollutants diverted to local receiving waters when detention...... ponds are not built-in the new separate sewer systems. If a total catchment area transformation – instead of only one fourth – is put through, the consequences could be fatal for receiving waters if no retention of pollutants is integrated in such a transformation....

  16. The Effect of Converting Combined Sewer Catchments to Separate Sewer Catchments

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Rasmussen, Michael R.; Thorndahl, Søren Liedtke

    2011-01-01

    The overall objective of this paper is to contribute to the standing debate concerning the advantages of separate sewer systems compared to traditional combined sewers. By a case study this investigation reveals that a transformation of one fourth of a given total area from being combined to become...... separate sewer catchments decreases the amounts of storm water and pollutants diverted to the waste water treatment plant (WWTP) or as combined sewer overflows (CSO). But this happens at the expense of an increase in amounts of storm water and pollutants diverted to local receiving waters when detention...... ponds are not built-in the new separate sewer systems. If a total catchment area transformation – instead of only one fourth – is put through, the consequences could be fatal for receiving waters if no retention of pollutants is integrated in such a transformation....

  17. Simulating groundwater-induced sewer flooding

    Science.gov (United States)

    Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

    2016-12-01

    During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.

  18. Predicting concrete corrosion of sewers using artificial neural network.

    Science.gov (United States)

    Jiang, Guangming; Keller, Jurg; Bond, Philip L; Yuan, Zhiguo

    2016-04-01

    Corrosion is often a major failure mechanism for concrete sewers and under such circumstances the sewer service life is largely determined by the progression of microbially induced concrete corrosion. The modelling of sewer processes has become possible due to the improved understanding of in-sewer transformation. Recent systematic studies about the correlation between the corrosion processes and sewer environment factors should be utilized to improve the prediction capability of service life by sewer models. This paper presents an artificial neural network (ANN)-based approach for modelling the concrete corrosion processes in sewers. The approach included predicting the time for the corrosion to initiate and then predicting the corrosion rate after the initiation period. The ANN model was trained and validated with long-term (4.5 years) corrosion data obtained in laboratory corrosion chambers, and further verified with field measurements in real sewers across Australia. The trained model estimated the corrosion initiation time and corrosion rates very close to those measured in Australian sewers. The ANN model performed better than a multiple regression model also developed on the same dataset. Additionally, the ANN model can serve as a prediction framework for sewer service life, which can be progressively improved and expanded by including corrosion rates measured in different sewer conditions. Furthermore, the proposed methodology holds promise to facilitate the construction of analytical models associated with corrosion processes of concrete sewers.

  19. 40 CFR 35.2024 - Combined sewer overflows.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Combined sewer overflows. 35.2024... from the State allotment for correction of combined sewer overflows provided that the project is on the... impacts of the combined sewer overflows and otherwise meets the requirements of this subpart. The...

  20. Self-optimising control of sewer systems

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Montero-Castro, I.; Mollerup, Ane Loft

    2013-01-01

    Self-optimising control is a useful concept to select optimal controlled variables from a set of candidate measurements in a systematic manner. In this study, use self-optimizing control tools and apply them to the specific features of sewer systems, e.g. the continuously transient dynamics......, the availability of a large number of measurements, the stochastic and unforeseeable character of the disturbances (rainfall). Using a subcatchment area in the Copenhagen sewer system as a case study we demonstrate, step by step, the formulation of the self-optimising control problem. The final result...... is an improved control structure aimed at optimizing the losses for a given control objective, here the minimization of the combined sewer overflows despite rainfall variations....

  1. On Hydraulic and Pollution Effects of Converting Combined Sewer Catchments to Separate Sewer Catchments

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Schaarup-Jensen, Kjeld; Rasmussen, Michael R.

    2015-01-01

    systems to become serviced with separate sewer systems decreases the volumes of storm water and pollutants diverted to the waste water treatment plant and discharged as combined sewer overflow. This happens at the expense of an increase in volumes of storm water and pollutant loads diverted to local...... receiving waters when detention ponds are not built-in the new separate sewer systems. It is concluded that consequences can be fatal for receiving waters, if no retention of pollutants is integrated into the system....

  2. Analysis and integrated modelling of groundwater infiltration to sewer networks

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Balling, Jonas Dueholm; Larsen, Uffe Bay Bøgh

    2016-01-01

    Infiltration of groundwater to sewer systems is a problem for the capacity of the system as well as for treatment processes at waste water treatment plants. This paper quantifies the infiltration of groundwater to a sewer system in Frederikshavn Municipality, Denmark, by measurements of sewer flow...... and novel model set-up, which simulates the interaction between groundwater and sewer flow. The study area has a separate waste water sewer system, but the discharged volumes from the system are approximately twice the volumes from a tight system without infiltration. The model set-up makes use of two...

  3. Value of Information for Sewer Replacement Decisions

    NARCIS (Netherlands)

    Van Riel, W.A.P.; Langeveld, J.G.; Herder, P.M.; Clemens, F.H.L.R.

    2014-01-01

    Decision-making for sewer asset management is partially based on intuition and often lacks explicit argumentation, hampering decision transparency and reproducibility. It is unknown to what extent each information source is appreciated by decision makers. Further insight into this relative

  4. Water Hammer in Pumped Sewer Mains

    DEFF Research Database (Denmark)

    Larsen, Torben

    This publication is intended for engineers seeking an introduction to the problem of water hammer in pumped pressure mains. This is a subject of increasing interest because of the development of larger and more integrated sewer systems. Consideration of water hammer is essential for structural...

  5. Agile Design of Sewer System Control

    NARCIS (Netherlands)

    Van Nooijen, R.P.; Kolechkina, A.G.; Van Leeuwen, P.E.R.M.; Van Velzen, E.

    2011-01-01

    We describe the first part of an attempt to include stakeholder participation in the design of a central automatic controller for a sewer system in a small pilot project (five subcatchments) and present lessons learned so far. The pilot is part of a project aimed at the improvement of water quality

  6. A Sediment Transport Model for Sewers

    DEFF Research Database (Denmark)

    Mark, Ole; Larsson, Johan; Larsen, Torben

    1993-01-01

    This paper describes a mathematical model for transport processes in sewers. The model consists of three sub models, a surface model for the description of the buildup and the washoff of sediment particles from the surface area, a morphological model and an advection-dispersion model. The model...

  7. Urban Runoff and Combined Sewer Overflow.

    Science.gov (United States)

    Field, Richard; Gardner, Bradford B.

    1978-01-01

    Presents a literature review of wastewater treatment, covering publications of 1976-77. This review includes areas such as: (1) urban runoff quality and quantity; (2) urban hydrology; (3) management practices; and (4) combined sewer overflows. A list of 140 references is also presented. (HM)

  8. Effects Of Leaky Sewers On Groundwater Quality

    Science.gov (United States)

    Leschik, S.; Musolff, A.; Reinstorf, F.; Strauch, G.; Oswald, S. E.; Schirmer, M.

    2007-12-01

    The impact of urban areas on groundwater quality has become an emerging research field in hydrogeology. Urban subsurface infrastructures like sewer networks are often leaky, so untreated wastewater may enter the urban aquifer. The transport of wastewater into the groundwater is still not well understood under field conditions. In the research platform WASSER Leipzig (Water And Sewershed Study of Environmental Risk in Leipzig- Germany) the effects of leaky sewers on the groundwater quality are investigated. The research is focused on the occurrence and transport of so-called "xenobiotics" such as pharmaceuticals and personal care product additives. Xenobiotics may pose a threat on human health, but can also be considered a marker for an urban impact on water resources. A new test site was established in Leipzig to quantify mass fluxes of xenobiotics into the groundwater from a leaky sewer. Corresponding to the leaks which were detected by closed circuit television inspections, monitoring wells were installed up- and downstream of the sewer. Concentrations of eight xenobiotics (technical-nonylphenol, bisphenol-a, caffeine, galaxolide, tonalide, carbamazepine, phenazone, ethinylestradiol) obtained from first sampling programmes were found to be highly heterogeneous, but a relation between the position of the sampling points and the sewer could not be clearly identified. However, concentrations of sodium, chloride, potassium and nitrate increased significantly downstream of the sewer which may be due to wastewater exfiltration, since no other source is known on the water flowpath from the upstream to the downstream wells. Because of the highly heterogeneous spatial distribution of xenobiotics at the test site, a monitoring concept was developed comprising both high-resolution sampling and an integral approach to obtain representative average concentrations. Direct-push techniques were used to gain insight into the fine-scale spatial distribution of the target compounds

  9. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  10. Characterization of Washoff Behavior of In-Sewer Deposits in Combined Sewer Systems.

    Science.gov (United States)

    Kim, WeonJae; Furumai, Hiroaki

    2016-06-01

    In-sewer deposits in combined sewer systems (CSSs) are closely related with the behavior of first foul flush and combined sewer overflows. The artificial flushing experiment separating the washoff of in-sewer deposits from the inflow of surface pollutants was carried out to simulate first foul flush in a CSS. The washoff behaviors of each pollutant including chemical pollutants, bacterial indicators, and enteric viruses were intensively investigated. By using several morphological analyses, some of which were suggested through this study, the characteristics of first foul flush were examined. As a result, the washoff behaviors of each pollutant were characterized according to their (i) event load ratios (ELRs), (ii) time-series concentration and load curves, (iii) concentration vs. flow rate curves, and (iv) dimensionless runoff concentrations (DRCs). The first foul flush patterns of each parameter were categorized into 3 typical groups: the strong-, partial-, and no first foul flush group. The order of these groups signifies their different physicochemical properties of in-sewer deposits in CSSs, their strength of first foul flush phenomena, and the washoff priority as well.

  11. Estimation of combined sewer overflow discharge

    DEFF Research Database (Denmark)

    Ahm, Malte; Thorndahl, Søren Liedtke; Nielsen, Jesper Ellerbæk;

    2016-01-01

    Combined sewer overflow (CSO) structures are constructed to effectively discharge excess water during heavy rainfall, to protect the urban drainage system from hydraulic overload. Consequently, most CSO structures are not constructed according to basic hydraulic principles for ideal measurement...... weirs. It can, therefore, be a challenge to quantify the discharges from CSOs. Quantification of CSO discharges are important in relation to the increased environmental awareness of the receiving water bodies. Furthermore, CSO discharge quantification is essential for closing the rainfall-runoff mass......-balance in combined sewer catchments. A closed mass-balance is an advantage for calibration of all urban drainage models based on mass-balance principles. This study presents three different software sensor concepts based on local water level sensors, which can be used to estimate CSO discharge volumes from hydraulic...

  12. Integrated planning of rehabilitation strategies for sewers.

    Science.gov (United States)

    Kleidorfer, Manfred; Möderl, Michael; Tscheikner-Gratl, Franz; Hammerer, Max; Kinzel, Heiko; Rauch, Wolfgang

    2013-01-01

    Building measures in sewer systems are increasingly driven by rehabilitation/retrofitting and adaptation needs. Aging infrastructure together with changing boundary conditions (due to climate change, land-use change, demographic change) and also changing design standards and legislation require a prospective design to preserve the functionality of urban drainage systems not only today, but also in a long-term perspective. To improve a prospective design of urban water infrastructure, the Austrian Research Promotion Agency funded the research project 'REHAB - Integrated planning of rehabilitation strategies of urban infrastructure systems'. Therein a novel strategic planning tool which considers these external drivers of rehabilitation strategies is developed. In this study the scope of the project is described and, as well as first results regarding sewer pipe conditions, future development and vulnerability assessment are also discussed.

  13. Water Hammer in Pumped Sewer Mains

    DEFF Research Database (Denmark)

    Larsen, Torben

    This publication is intended for students and engineers seeking an introduction to the problem of water transients in pumped sewer and water mains. This is a subject of increasing interest because of the development of larger and more integrated systems. Consideration of transients is essential...... for the structural design of pipelines and for the planning of the proper function of the systems. The text is written by Torben Larsen, who is a professor of environmental hydraulics at the Department of Civil Engineering, Aalborg University. Torben Larsen has many years of experience with computer simulations...... of transients in pumped pipeline systems. This present publication can be understood as the second and revised edition of the pamphlet ”Transients in pumped sewer mains” (2006) which was published as a technical report by The EVA committee under The Danish Water Pollution Committee (The Danish Society...

  14. Treatment of Sewer Water Using Alum Salt

    OpenAIRE

    Qaid M. Saleem; Yousif Mohamed Algamal; Majed H. Shtaiwi; Mohammad S. Aldahmashi

    2014-01-01

    This investigation was carried out to study the effect of addition of different concentrations of alum salt used in the treatment of sewer water of the pond and also to study the physico-chemical parameters such as pH ,electrical conductivity ,salinity and total sediments besides that the bacteriological analysis such as total viable count (TVC) or standard plate count (SPC) and total coliform count (MPN) content were analysed in the water sample collected from the pond estimation of viable...

  15. Measuring Flow Reductions in a Combined Sewer System using Green Infrastructure - abstract

    Science.gov (United States)

    In 2009, the Louisville and Jefferson County Metropolitan Sewer District (MSD) submitted an Integrated Overflow Abatement Plan (IOAP) addressing combined sewer overflows (CSOs) and sanitary sewer overflows. Many of the solutions involve gray infrastructure, such as large, end-of...

  16. The Historical Development of Sewers Worldwide

    Directory of Open Access Journals (Sweden)

    Giovanni De Feo

    2014-06-01

    Full Text Available Although there is evidence of surface-based storm drainage systems in early Babylonian and Mesopotamian Empires in Iraq (ca. 4000–2500 BC, it is not until after ca. 3000 BC that we find evidence of the well organized and operated sewer and drainage systems of the Minoans and Harappans in Crete and the Indus valley, respectively. The Minoans and Indus valley civilizations originally, and the Hellenes and Romans thereafter, are considered pioneers in developing basic sewerage and drainage technologies, with emphasis on sanitation in the urban environment. The Hellenes and Romans further developed these techniques and greatly increased the scale of these systems. Although other ancient civilizations also contributed, notably some of the Chinese dynasties, very little progress was made during the Dark ages from ca. 300 AD through to the middle of the 18th century. It was only from 1850 onwards that that modern sewerage was “reborn”, but many of the principles grasped by the ancients are still in use today. This paper traces the development of the sewer from those earliest of civilizations through to the present day and beyond. A 6000 year technological history is a powerful validation of the vital contribution of sewers to human history.

  17. New Findings in Hydrogen Sulfide Related Corrosion of Concrete Sewers

    DEFF Research Database (Denmark)

    Nielsen, Asbjørn Haaning; Jensen, Henriette Stokbro; Hvitved-Jacobsen, Thorkild

    2009-01-01

    This paper summarizes major findings of a long-term study of hydrogen sulfide gas (H2S) adsorption and oxidation on concrete and plastic sewer pipe surfaces. The processes have been studied using a pilot-scale setup designed to replicate conditions in a gravity sewer located downstream of a force...... H2S concentration in concrete sewers would typically amount to a few percent of the equilibrium concentration calculated from Henrys law. In plastic pipe sewers, significantly higher concentrations were predicted because of the slower adsorption and oxidation kinetics on these surfaces. Finally...

  18. Using data from monitoring combined sewer overflows to assess, improve, and maintain combined sewer systems

    OpenAIRE

    Montserrat Royuela, Albert; Bosch, Ll.; Kiser, M.A.; Poch, Manuel; Corominas Tabares, Lluís

    2015-01-01

    Using low-cost sensors, data can be collected on the occurrence and duration of overflows in each combined sewer overflow (CSO) structure in a combined sewer system (CSS). The collection and analysis of real data can be used to assess, improve, and maintain CSSs in order to reduce the number and impact of overflows. The objective of this study was to develop a methodology to evaluate the performance of CSSs using low-cost monitoring. This methodology includes (1) assessing the capacity of a C...

  19. Clean data

    CERN Document Server

    Squire, Megan

    2015-01-01

    If you are a data scientist of any level, beginners included, and interested in cleaning up your data, this is the book for you! Experience with Python or PHP is assumed, but no previous knowledge of data cleaning is needed.

  20. Identification of in-sewer sources of organic solids contributing to combined sewer overflows.

    Science.gov (United States)

    Ahyerre, M; Chebbo, G

    2002-09-01

    Previous research has shown that combined sewer systems are the main source of particle and organic pollution during rainfall events contributing to combined sewer overflow. The aim of this article is to identify in an urban catchment area called "Le Marais", in the center of Paris, the types of sediments that are eroded and contribute to the pollution of combined sewer overflow. Three sediment types are considered: granular material found in the inverts of pipes, organic biofilms and organic sediment at the water bed interface, identified as an immobile layer in the "Le Marais" catchment area. The method used consist, firstly, of sampling and assessing the organic pollutant loads and metallic loads of the particles in each type of sediment. Then, the mass of each type of sediment is assessed. The mass and the characteristics of each type of sediment is finally compared to the mass and characteristics of the particles eroded in the catchment area, estimated by mass balances, in order to find the source of eroded particles. The only identified type of deposit that can contribute to combined sewer overflows is the organic layer. Indeed, the solids of this layer have mean and metallic loads that are of the same order of magnitude as the eroded particles. Moreover, the mass of the organic layer considered over different time scales is of the same order of magnitude as the eroded masses during rainfall events and an erosion experiment showed that the organic layer is actually eroded.

  1. Recent findings on sinks for sulfide in gravity sewer networks

    DEFF Research Database (Denmark)

    Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes

    2006-01-01

    summarizes this newly obtained knowledge and emphasizes important implications of the findings. Model simulations of the in-sewer processes important for the sulfur cycle showed that sulfide oxidation in the wetted biofilm is typically the most important sink for dissolved sulfide in gravity sewers. However...

  2. A biofilm model for prediction of pollutant transformation in sewers.

    Science.gov (United States)

    Jiang, Feng; Leung, Derek Hoi-Wai; Li, Shiyu; Chen, Guang-Hao; Okabe, Satoshi; van Loosdrecht, Mark C M

    2009-07-01

    This study developed a new sewer biofilm model to simulate the pollutant transformation and biofilm variation in sewers under aerobic, anoxic and anaerobic conditions. The biofilm model can describe the activities of heterotrophic, autotrophic, and sulfate-reducing bacteria (SRB) in the biofilm as well as the variations in biofilm thickness, the spatial profiles of SRB population and biofilm density. The model can describe dynamic biofilm growth, multiple biomass evolution and competitions among organic oxidation, denitrification, nitrification, sulfate reduction and sulfide oxidation in a heterogeneous biofilm growing in a sewer. The model has been extensively verified by three different approaches, including direct verification by measurement of the spatial concentration profiles of dissolved oxygen, nitrate, ammonia, and hydrogen sulfide in sewer biofilm. The spatial distribution profile of SRB in sewer biofilm was determined from the fluorescent in situ hybridization (FISH) images taken by a confocal laser scanning microscope (CLSM) and were predicted well by the model.

  3. Integrated design of sewers and wastewater treatment plants.

    Science.gov (United States)

    Vollertsen, J; Hvitved-Jacobsen, T; Ujang, Z; Talib, S A

    2002-01-01

    Sewer system design must be integrated with wastewater treatment plant design when moving towards a more sustainable urban wastewater management. This integration allows an optimization of the design of both systems to achieve a better and more cost-effective wastewater management. Hitherto integrated process design has not been an option because the tools to predict in-sewer wastewater transformations have been inadequate. In this study the WATS model--being a new and validated tool for in-sewer microbial process simulations--is presented and its application for integrated sewer and treatment plant design is exemplified. A case study on a Malaysian catchment illustrates this integration. The effects of centralization of wastewater treatment and the subsequently longer transport distances are addressed. The layout of the intercepting sewer is optimized to meet the requirements of different treatment scenarios.

  4. Valuing information for sewer replacement decisions.

    Science.gov (United States)

    van Riel, Wouter; Langeveld, Jeroen; Herder, Paulien; Clemens, François

    Decision-making for sewer asset management is partially based on intuition and often lacks explicit argumentation, hampering decision transparency and reproducibility. This is not to be preferred in light of public accountability and cost-effectiveness. It is unknown to what extent each decision criterion is appreciated by decision-makers. Further insight into this relative importance improves understanding of decision-making of sewer system managers. As such, a digital questionnaire (response ratio 43%), containing pairwise comparisons between 10 relevant information sources, was sent to all 407 municipalities in the Netherlands to analyse the relative importance and assess whether a shared frame of reasoning is present. Thurstone's law of comparative judgment was used for analysis, combined with several consistency tests. Results show that camera inspections were valued highest, while pipe age was considered least important. The respondents were pretty consistent per individual and also showed consistency as a group. This indicated a common framework of reasoning among the group. The feedback of the group showed, however, the respondents found it difficult to make general comparisons without having a context. This indicates decision-making in practice is more likely to be steered by other mechanisms than purely combining information sources.

  5. Radar Based Flow and Water Level Forecasting in Sewer Systems

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Rasmussen, Michael R.; Grum, M.

    2009-01-01

    This paper describes the first radar based forecast of flow and/or water level in sewer systems in Denmark. The rainfall is successfully forecasted with a lead time of 1-2 hours, and flow/levels are forecasted an additional ½-1½ hours using models describing the behaviour of the sewer system. Both...... radar data and flow/water level model are continuously updated using online rain gauges and online in-sewer measurements, in order to make the best possible predictions. The project show very promising results, and show large potentials, exploiting the existing water infrastructure in future climate...

  6. Numerical Modelling Approaches for Sediment Transport in Sewer Systems

    DEFF Research Database (Denmark)

    Mark, Ole

    A study of the sediment transport processes in sewers has been carried out. Based on this study a mathematical modelling system has been developed to describe the transport processes of sediments and dissolved matter in sewer systems. The modelling system consists of three sub-models which...... constitute the basic modelling system necessary to give a discription of the most dominant physical transport processes concerning particles and dissolved matter in sewer systems: A surface model. An advection-dispersion model. A sediment transport model....

  7. A methodological approach to designing sewer system control

    DEFF Research Database (Denmark)

    Mollerup, Ane Loft

    for this thesis was therefore the wish for a methodological approach to sewer system control design. Using a case study the following research hypothesis was tested in this thesis: Using classical and modern control theory, a methodological approach can be derived for designing sewer system control. This can aid...... urban drainage planner and other professionals in the planning phase of sewer system con-trol design and effectively contribute to find novel control solution. It was investigated if the established methodology used in classic control the-ory for process control design can be applied meaningfully....... This was not unexpected, since the true potential of having optimisation arises, when a system has many control loops with limit-ing constraints and/or changing prioritisation between them. The results showed that for small sewer systems, where the complexity is limited, it is not necessarily the best option to implement...

  8. Colorado River Sewer System Joint Venture to Upgrade Wastewater System

    Science.gov (United States)

    SAN FRANCISCO -Today, the Colorado River Sewer System Joint Venture, located in Parker, Ariz. entered into an agreement with the EPA to upgrade their wastewater treatment system to meet stringent water quality standards. The cost of the upgrade is ap

  9. Safe Drinking Water Information System (SDWIS) Sewer Treatment Plants

    Data.gov (United States)

    U.S. Environmental Protection Agency — This is a point feature dataset showing the locations of sewer treatment plants. These facility locations are part of the safe drinking water information system...

  10. Sandia National Laboratories, California sewer system management plan.

    Energy Technology Data Exchange (ETDEWEB)

    Holland, Robert C.

    2010-02-01

    A Sewer System Management Plan (SSMP) is required by the State Water Resources Control Board (SWRCB) Order No. 2006-0003-DWQ Statewide General Waste Discharge Requirements (WDR) for Sanitary Sewer Systems (General Permit). DOE, National Nuclear Security Administration (NNSA), Sandia Site Office has filed a Notice of Intent to be covered under this General Permit. The General Permit requires a proactive approach to reduce the number and frequency of sanitary sewer overflows (SSOs) within the State. SSMPs must include provisions to provide proper and efficient management, operation, and maintenance of sanitary sewer systems and must contain a spill response plan. Elements of this Plan are under development in accordance with the SWRCB's schedule.

  11. Development of Sediment Deposition Height Capacity Equation in Sewer Networks

    Science.gov (United States)

    Song, Yangho; Jo, Deokjun; Lee, Jungho

    2017-04-01

    Sediment characteristics and transport processes in sewers are markedly different from river. There is a wide range of particle densities and smaller particle size variation in sewers. Sediment supply and the available erodible material are more limited in sewers, and the diverse hydraulic characteristics in sewer systems are more unsteady. Prevention of sewer sediment accumulation, which can cause major sewer operational problems, is imperative and has been an immense concern for engineers. The effects of sediment formation in sewer systems, an appropriate sediment transport modelling with the ability to determine the location and depth of sediment deposit is needed. It is necessary to design efficiently considering the transfer and settling phenomena of the sediment coming into the sewer systems. During transport in the sewer, the minimum shear flow velocity and possible shear stress at which the sediment is transported smoothly. However, the interaction of sediment and fluid within the sewer systems has been very complex and the rigorous theoretical handling of this problem has not been developed. It is derived from the empirical values obtained from the river bed. The basic theory that particles float is based on the balance between sedimentation of particles by gravity and turbulent diffusion of fluids. There are many variables related. Representative parameters include complex phenomena due to collisions between particles, particles and fluids, and interactions between particles and tube walls. In general, the main parameters that form the boundary between the main transport and sediment are particle size, density, volume fraction, pipe diameter and gravity. As the particle size and volume concentration increase, the minimum feed rate increases and the same tendency is observed for the change of the capillary diameter. Based on this tendency, this study has developed a sediment deposition height capacity formula to take into consideration the sewer discharge

  12. SEWER NETWORK DISCHARGE OPTIMIZATION USING THE DYNAMIC PROGRAMMING

    Directory of Open Access Journals (Sweden)

    Viorel MINZU

    2015-12-01

    Full Text Available It is necessary to adopt an optimal control that allows an efficient usage of the existing sewer networks, in order to avoid the building of new retention facilities. The main objective of the control action is to minimize the overflow volume of a sewer network. This paper proposes a method to apply a solution obtained by discrete dynamic programming through a realistic closed loop system.

  13. [Development of an automatic ultrasonic cleaning machine for surgical instruments].

    Science.gov (United States)

    Geng, Shu-qing; He, Wei; Tao, Ren-hai; Ma, Bao-Qiu; Lu, Hai-long; Li, Li-hua; Feng, Hui-zhi; Zheng, Jin-zhi

    2005-11-01

    The automatic cleaning machine we have developed, adopts a SCM system in automatic cleaning. The machine has five functions: ultrasonic cleaning, cold or hot water spraying, drying and greasing. The clinical applications show that the machine with a good effectiveness is suitable for the cleaning of many surgical instruments. It also raises working efficiency, cuts down on the cost of repair and maintenance and reduces the injury and infection to nurses caused by manual cleaning, satisfying the needs of clinical applications.

  14. Factors affecting economies of scale in combined sewer systems.

    Science.gov (United States)

    Maurer, Max; Wolfram, Martin; Anja, Herlyn

    2010-01-01

    A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.

  15. Utilities:Water:Sewer Line Nodes at Pipe Spring National Monument, Arizona (Utilities.gdb:Water:sewer_node)

    Data.gov (United States)

    National Park Service, Department of the Interior — This feature class represents sewer line nodes at Pipe Spring National Monument, Arizona. The data were collected using Trimble Global Positioning System (GPS) units...

  16. 76 FR 3159 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2011-01-19

    ... to cause violations of applicable water quality standards for E. coli in the receiving streams; (2... of Lodging of a Consent Decree Under the Clean Water Act Notice is hereby given that on January 6... and Evansville Water and Sewer Utility Board, Civil Action No. 3:09-CV-128, was lodged with the...

  17. Postural stability assessment in sewer workers.

    Science.gov (United States)

    Kuo, W; Bhattacharya, A; Succop, P; Linz, D

    1996-01-01

    In this study, postural stability was measured with a microcomputer-based force platform as an indirect assessment of central nervous system effect in 28 sewer workers (age range 23.4 to 64.5 years, standard deviation of 8.7 years). All workers performed four 30-second postural sway tests. The organic-solvent exposure was measured by a photo-ionization detector. The photo-ionization detector was calibrated to measure volatile organic solvents in total benzene equivalence, and concentrations were measured in various parts of the plant. The mean exposure was .32 parts per million (ppm) benzene equivalent (range of .02 to .95 ppm, standard deviation .19 ppm). Based on a covariate adjusted linear multiple-regression model, a statistically significant (p organic-solvent exposure. These workers also had increased postural sway compared with a nonexposed population. The statistically significant correlation between postural sway determinations and organic-solvent exposure was surprising given the very low exposures measured. It is possible that the organic-solvent exposure might not be the causative agent, but rather that the solvents themselves correlate with some other causative exposure, ie, total volatile organics as implicated in the cause of sick-building syndrome.

  18. Priority substances in combined sewer overflows: case study of the Paris sewer network.

    Science.gov (United States)

    Gasperi, J; Garnaud, S; Rocher, V; Moilleron, R

    2011-01-01

    This study was undertaken to supply data on both priority pollutant (PP) occurrence and concentrations in combined sewer overflows (CSOs). A single rain event was studied on 13 sites within the Paris sewer network. For each sample, a total of 66 substances, including metals, polycyclic aromatic hydrocarbons (PAHs), pesticides, organotins, volatile organic compounds, chlorobenzenes, phthalates and alkylphenols were analyzed. Of the 66 compounds analyzed in all, 40 PPs including 12 priority hazardous substances were detected in CSOs. As expected, most metals were present in all samples, reflecting their ubiquitous nature. Chlorobenzenes and most pesticides were never quantified above the limit of quantification, while the majority of the other organic pollutants, except DEHP (median concentration: 22 μg.l(-1)), were found to lie in the μg.l(-1) range. For the particular rain event studied, the pollutant loads discharged by CSOs were evaluated and then compared to pollutant loads conveyed by the Seine River. Under the hydraulic conditions considered and according to the estimations performed, this comparison suggests that CSOs are potentially significant local source of metals, PAHs and DEHP. Depending on the substance, the ratio between the CSO and Seine River loads varied from 0.5 to 26, underscoring the important local impact of CSOs at the scale of this storm for most pollutants.

  19. Using data from monitoring combined sewer overflows to assess, improve, and maintain combined sewer systems.

    Science.gov (United States)

    Montserrat, A; Bosch, Ll; Kiser, M A; Poch, M; Corominas, Ll

    2015-02-01

    Using low-cost sensors, data can be collected on the occurrence and duration of overflows in each combined sewer overflow (CSO) structure in a combined sewer system (CSS). The collection and analysis of real data can be used to assess, improve, and maintain CSSs in order to reduce the number and impact of overflows. The objective of this study was to develop a methodology to evaluate the performance of CSSs using low-cost monitoring. This methodology includes (1) assessing the capacity of a CSS using overflow duration and rain volume data, (2) characterizing the performance of CSO structures with statistics, (3) evaluating the compliance of a CSS with government guidelines, and (4) generating decision tree models to provide support to managers for making decisions about system maintenance. The methodology is demonstrated with a case study of a CSS in La Garriga, Spain. The rain volume breaking point from which CSO structures started to overflow ranged from 0.6 mm to 2.8 mm. The structures with the best and worst performance in terms of overflow (overflow probability, order, duration and CSO ranking) were characterized. Most of the obtained decision trees to predict overflows from rain data had accuracies ranging from 70% to 83%. The results obtained from the proposed methodology can greatly support managers and engineers dealing with real-world problems, improvements, and maintenance of CSSs.

  20. Sulfide elimination by intermittent nitrate dosing in sewer sediments

    Institute of Scientific and Technical Information of China (English)

    Yanchen Liu; Chen Wu; Xiaohong Zhou; David Z.Zhu; Hanchang Shi

    2015-01-01

    The formation of hydrogen sulfide in biofilms and sediments in sewer systems can cause severe pipe corrosions and health hazards,and requires expensive programs for its prevention.The aim of this study is to propose a new control strategy and the optimal condition for sulfide elimination by intermittent nitrate dosing in sewer sediments.The study was carried out based on lab-scale experiments and batch tests using real sewer sediments.The intermittent nitrate dosing mode and the optimal control condition were investigated.The results indicated that the sulfide-intermittent-elimination strategy by nitrate dosing is advantageous for controlling sulfide accumulation in sewer sediment.The oxidation-reduction potential is a sensitive indicator parameter that can reflect the control effect and the minimum N/S (nitrate/sulfide)ratio with slight excess nitrate is necessary for optimal conditions ofefficient sulfide control with lower carbon source loss.The opth-nal control condition is feasible for the sulfide elimination in sewer systems.

  1. Wastewater-Enhanced Microbial Corrosion of Concrete Sewers.

    Science.gov (United States)

    Jiang, Guangming; Zhou, Mi; Chiu, Tsz Ho; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

    2016-08-02

    Microbial corrosion of concrete in sewers is known to be caused by hydrogen sulfide, although the role of wastewater in regulating the corrosion processes is poorly understood. Flooding and splashing of wastewater in sewers periodically inoculates the concrete surface in sewer pipes. No study has systematically investigated the impacts of wastewater inoculation on the corrosion of concrete in sewers. This study investigated the development of the microbial community, sulfide uptake activity, and the change of the concrete properties for coupons subjected to periodic wastewater inoculation. The concrete coupons were exposed to different levels of hydrogen sulfide under well-controlled conditions in laboratory-scale corrosion chambers simulating real sewers. It was evident that the periodic inoculation induced higher corrosion losses of the concrete in comparison to noninoculated coupons. Instantaneous measurements such as surface pH did not reflect the cumulative corrosion losses caused by long-term microbial activity. Analysis of the long-term profiles of the sulfide uptake rate using a Gompertz model supported the enhanced corrosion activity and greater corrosion loss. The enhanced corrosion rate was due to the higher sulfide uptake rates induced by wastewater inoculation, although the increasing trend of sulfide uptake rates was slower with wastewater. Increased diversity in the corrosion-layer microbial communities was detected when the corrosion rates were higher. This coincided with the environmental conditions of increased levels of gaseous H2S and the concrete type.

  2. Comparison of core sampling and visual inspection for assessment of sewer pipe condition

    NARCIS (Netherlands)

    Stanic, N.; Haan, C.; Tirion, M.; Langeveld, J.G.; Clemens, F.H.L.R.

    2012-01-01

    Sewer systems are costly to construct and even more costly to replace, requiring proper asset management Sewer asset management relies to a large extent on available information. In sewer systems where pipe corrosion is the dominant failure mechanism, visual inspection (CCTV) and core sampling are a

  3. Comparison of core sampling and visual inspection for assessment of sewer pipe condition

    NARCIS (Netherlands)

    Stanic, N.; Haan, C.; Tirion, M.; Langeveld, J.G.; Clemens, F.H.L.R.

    2012-01-01

    Sewer systems are costly to construct and even more costly to replace, requiring proper asset management Sewer asset management relies to a large extent on available information. In sewer systems where pipe corrosion is the dominant failure mechanism, visual inspection (CCTV) and core sampling are a

  4. Comparison of core sampling and visual inspection for assessment of sewer pipe condition

    NARCIS (Netherlands)

    Stanic, N.; Haan, C.; Tirion, M.; Langeveld, J.G.; Clemens, F.H.L.R.

    2012-01-01

    Sewer systems are costly to construct and even more costly to replace, requiring proper asset management Sewer asset management relies to a large extent on available information. In sewer systems where pipe corrosion is the dominant failure mechanism, visual inspection (CCTV) and core sampling are

  5. Long-term pollution simulation in combined sewer networks.

    Science.gov (United States)

    Masse, B; Zug, M; Tabuchi, J P; Tisserand, B

    2001-01-01

    This paper presents results of long term pollution simulations on the example of the sewerage system of Grand-Couronne. This modelling work is part of a study where objective is to develop a method to define the reference flow of a WWTP. The model HYDROWORKS DM has been successfully validated in hydraulics and pollution for the sewer network, for long time simulations. A conceptual model has been built to model the pollution in the tank at the outlet of the combined system. One synthetic year of rain has been used to simulate the working of the "up stream system" of the WWTP (combined sewer + tank + separate sewer + pre-treatments) and has been successfully validated by measurements of the 1998-1999 year. If this paper is focused on the "up stream system", the SIMBA/SIMBAD WWTP model has been successfully calibrated and validated too, and the combination represents a fully validated "Integrated Model" for the sewerage system.

  6. Molecular survey of concrete sewer biofilm microbial communities.

    Science.gov (United States)

    Santo Domingo, Jorge W; Revetta, Randy P; Iker, Brandon; Gomez-Alvarez, Vicente; Garcia, Jarissa; Sullivan, John; Weast, James

    2011-10-01

    The microbial composition of concrete biofilms within wastewater collection systems was studied using molecular assays. SSU rDNA clone libraries were generated from 16 concrete surfaces of manholes, a combined sewer overflow, and sections of a corroded sewer pipe. Of the 2457 sequences analyzed, α-, β-, γ-, and δ-Proteobacteria represented 15%, 22%, 11%, and 4% of the clones, respectively. β-Proteobacteria (47%) sequences were more abundant in the pipe crown than any of the other concrete surfaces. While 178 to 493 Operational Taxonomic Units (OTUs) were associated with the different concrete samples, only four sequences were shared among the different clone libraries. Bacteria implicated in concrete corrosion were found in the clone libraries while archaea, fungi, and several bacterial groups were also detected using group-specific assays. The results showed that concrete sewer biofilms are more diverse than previously reported. A more comprehensive molecular database will be needed to better study the dynamics of concrete biofilms.

  7. Migrating Storms and Optimal Control of Urban Sewer Networks

    Directory of Open Access Journals (Sweden)

    Upaka Rathnayake

    2015-11-01

    Full Text Available Uniform storms are generally applied in most of the research on sewer systems. This is for modeling simplicity. However, in the real world, these conditions may not be applicable. It is very important to consider the migration behavior of storms not only in the design of combined sewers, but also in controlling them. Therefore, this research was carried out to improve Rathnayake and Tanyimboh’s optimal control algorithm for migrating storms. Promising results were found from the model improvement. Feasible solutions were obtained from the multi-objective optimization and, in addition, the role of on-line storage tanks was well placed.

  8. Risk assessment of sewer condition using artificial intelligence tools: application to the SANEST sewer system.

    Science.gov (United States)

    Sousa, V; Matos, J P; Almeida, N; Saldanha Matos, J

    2014-01-01

    Operation, maintenance and rehabilitation comprise the main concerns of wastewater infrastructure asset management. Given the nature of the service provided by a wastewater system and the characteristics of the supporting infrastructure, technical issues are relevant to support asset management decisions. In particular, in densely urbanized areas served by large, complex and aging sewer networks, the sustainability of the infrastructures largely depends on the implementation of an efficient asset management system. The efficiency of such a system may be enhanced with technical decision support tools. This paper describes the role of artificial intelligence tools such as artificial neural networks and support vector machines for assisting the planning of operation and maintenance activities of wastewater infrastructures. A case study of the application of this type of tool to the wastewater infrastructures of Sistema de Saneamento da Costa do Estoril is presented.

  9. Damage estimation of sewer pipe using subtitles of CCTV inspection video

    Science.gov (United States)

    Park, Kitae; Kim, Byeongcheol; Kim, Taeheon; Seo, Dongwoo

    2017-04-01

    Recent frequent occurrence of urban sinkhole serves as a momentum of the periodic inspection of sewer pipelines. Sewer inspection using a CCTV device needs a lot of time and efforts. Many of previous studies which reduce the laborious tasks are mainly interested in the developments of image processing S/W and exploring H/W. And there has been no attempt to find meaningful information from the existing CCTV images stored by the sewer maintenance manager. This study adopts a cross-correlation based image processing method and extracts sewer inspection device's location data from CCTV images. As a result of the analysis of location-time relation, it show strong correlation between device stand time and the sewer damages. In case of using this method to investigate sewer inspection CCTV images, it will save the investigator's efforts and improve sewer maintenance efficiency and reliability.

  10. Modeling Sulfides, pH and Hydrogen Sulfide Gas in the Sewers of San Francisco

    DEFF Research Database (Denmark)

    Vollertsen, Jes; Revilla, Nohemy; Hvitved-Jacobsen, Thorkild

    2015-01-01

    An extensive measuring campaign targeted on sewer odor problems was undertaken in San Francisco. It was assessed whether a conceptual sewer process model could reproduce the measured concentrations of total sulfide in the wastewater and H2S gas in the sewer atmosphere, and to which degree...... such simulations have potential for further improving odor and sulfide management. The campaign covered measurement of wastewater sulfide by grab sampling and diurnal sampling, and H2S gas in the sewer atmosphere was logged. The tested model was based on the Wastewater Aerobic/Anaerobic Transformations in Sewers...... (WATS) sewer process concept, which never had been calibrated to such an extensive dataset. The study showed that the model was capable of reproducing the general levels of wastewater sulfide, wastewater pH, and sewer H2S gas. It could also reproduce the general variability of these parameters, albeit...

  11. Real Rainfall Time Series for Storm Sewer Design

    DEFF Research Database (Denmark)

    Larsen, Torben

    1981-01-01

    This paper describes a simulation method for the design of retention storages, overflows etc. in storm sewer systems. The method is based on computer simulation with real real rainfall time series as input and with a simple transfer model of the ARMA-type (Autoregressive moving average) applied...

  12. Real Rainfall Time Series for Storm Sewer Design

    DEFF Research Database (Denmark)

    Larsen, Torben

    The paper describes a simulation method for the design of retention storages, overflows etc. in storm sewer systems. The method is based on computer simulation with real rainfall time series as input ans with the aply of a simple transfer model of the ARMA-type (autoregressiv moving average model...

  13. Measurements and Computations of Transients in Pumped Sewer Plastic Mains

    DEFF Research Database (Denmark)

    Larsen, Torben; Burrows, Richard

    1992-01-01

    Measurements of pressure and flow in a number of pumped plastic sewer mains have been carried out in order to compare the actual observed transients with computations. Primarily the situation following pump run-down has been studied. The investigation covered pipelines with steadily rising length...

  14. 40 CFR 35.927 - Sewer system evaluation and rehabilitation.

    Science.gov (United States)

    2010-07-01

    ... rehabilitation. 35.927 Section 35.927 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER... § 35.927 Sewer system evaluation and rehabilitation. (a) All applicants for step 2 or step 3 grant... evaluation survey and, if appropriate, a program, including an estimate of costs, for rehabilitation of...

  15. HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

    Science.gov (United States)

    This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...

  16. Incorporating Storm Sewer Exfiltration into SWMM: Proof of Concept

    Science.gov (United States)

    This study evaluates the peak flow and volume reduction achieved by exfiltration from a perforated storm sewer in an urban catchment. There are three related objectives: [1] quantify peak flow and volume reduction; [2] demonstrate adaptability to climate change; and [3] evaluate ...

  17. Online dissolved methane and total dissolved sulfide measurement in sewers.

    Science.gov (United States)

    Liu, Yiwen; Sharma, Keshab R; Fluggen, Markus; O'Halloran, Kelly; Murthy, Sudhir; Yuan, Zhiguo

    2015-01-01

    Recent studies using short-term manual sampling of sewage followed by off-line laboratory gas chromatography (GC) measurement have shown that a substantial amount of dissolved methane is produced in sewer systems. However, only limited data has been acquired to date due to the low frequency and short span of this method, which cannot capture the dynamic variations of in-sewer dissolved methane concentrations. In this study, a newly developed online measuring device was used to monitor dissolved methane concentrations at the end of a rising main sewer network, over two periods of three weeks each, in summer and early winter, respectively. This device uses an online gas-phase methane sensor to measure methane under equilibrium conditions after being stripped from the sewage. The data are then converted to liquid-phase methane concentrations according to Henry's Law. The detection limit and range are suitable for sewer application and can be adjusted by varying the ratio of liquid-to-gas phase volume settings. The measurement presented good linearity (R² > 0.95) during field application, when compared to off-line measurements. The overall data set showed a wide variation in dissolved methane concentration of 5-15 mg/L in summer and 3.5-12 mg/L in winter, resulting in a significant average daily production of 24.6 and 19.0 kg-CH₄/d, respectively, from the network with a daily average sewage flow of 2840 m³/day. The dissolved methane concentration demonstrated a clear diurnal pattern coinciding with flow and sulfide fluctuation, implying a relationship with the wastewater hydraulic retention time (HRT). The total dissolved sulfide (TDS) concentration in sewers can be determined simultaneously with the same principle.

  18. Network condition simulator for benchmarking sewer deterioration models.

    Science.gov (United States)

    Scheidegger, A; Hug, T; Rieckermann, J; Maurer, M

    2011-10-15

    An accurate description of aging and deterioration of urban drainage systems is necessary for optimal investment and rehabilitation planning. Due to a general lack of suitable datasets, network condition models are rarely validated, and if so with varying levels of success. We therefore propose a novel network condition simulator (NetCoS) that produces a synthetic population of sewer sections with a given condition-class distribution. NetCoS can be used to benchmark deterioration models and guide utilities in the selection of appropriate models and data management strategies. The underlying probabilistic model considers three main processes: a) deterioration, b) replacement policy, and c) expansions of the sewer network. The deterioration model features a semi-Markov chain that uses transition probabilities based on user-defined survival functions. The replacement policy is approximated with a condition-class dependent probability of replacing a sewer pipe. The model then simulates the course of the sewer sections from the installation of the first line to the present, adding new pipes based on the defined replacement and expansion program. We demonstrate the usefulness of NetCoS in two examples where we quantify the influence of incomplete data and inspection frequency on the parameter estimation of a cohort survival model and a Markov deterioration model. Our results show that typical available sewer inventory data with discarded historical data overestimate the average life expectancy by up to 200 years. Although NetCoS cannot prove the validity of a particular deterioration model, it is useful to reveal its possible limitations and shortcomings and quantifies the effects of missing or uncertain data. Future developments should include additional processes, for example to investigate the long-term effect of pipe rehabilitation measures, such as inliners. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Sulfide and methane production in sewer sediments: Field survey and model evaluation.

    Science.gov (United States)

    Liu, Yiwen; Tugtas, A Evren; Sharma, Keshab R; Ni, Bing-Jie; Yuan, Zhiguo

    2016-02-01

    Sewer sediment processes have been reported to significantly contribute to overall sulfide and methane production in sewers, at a scale comparable to that of sewer biofilms. The physiochemical and biological characteristics of sewer sediments are heterogeneous; however, the variability of in-sediments sulfide and methane production rates among sewers has not been assessed to date. In this study, five sewer sediment samples were collected from two cities in Australia with different climatic conditions. Batch assays were conducted to determine the rates of sulfate reduction and methane production under different flow velocity (shear stress) conditions as well as under completely mixed conditions. The tests showed substantial and variable sulfate reduction and methane production activities among different sediments. Sulfate reduction and methane production from sewer sediments were confirmed to be areal processes, and were dependent on flow velocity/shear stress. Despite of the varying characteristics and reactions kinetics, the sulfate reduction and methane production processes in all sediments could be well described by a one-dimensional sewer sediment model recently developed based on results obtained from a laboratory sewer sediment reactor. Model simulations indicated that the in-situ contribution of sewer sediment emissions could be estimated without the requirement of measuring the specific sediment characteristics or the sediment depths.

  20. 76 FR 53941 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2011-08-30

    ... Euclid's operation of its municipal wastewater and sewer system. The Complaint alleges that the City discharges combined sewer overflows (``CSOs'') and sanitary sewer overflows (``SSOs'') in violation of...

  1. Air Flows in Gravity Sewers - Determination of Wastewater Drag Coefficient

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Østertoft, Kristian; Vollertsen, Jes

    2016-01-01

    of the study shows that by integrating the top/side wall shear stresses the log-law models for the air velocity distribution along the unwetted perimeter resulted in a good agreement with the friction forces calculated by use of the Colebrook-White formula for hydraulic smooth pipes. Secondly, the water......Several experiments have been conducted in order to improve the understanding of the wastewater drag and the wall frictional force acting on the headspace air in gravity sewers. The aim of the study is to improve the data basis for a numerical model of natural sewer ventilation. The results...... surface drags were found by log-law models of the velocity distribution in turbulent flows to fit velocity profiles measured from the water surface and by integrating the water surface drags along the wetted perimeter, mean water surface drags were found and a measure of the water surface drag coefficient...

  2. Regulatory control analysis and design for sewer systems

    DEFF Research Database (Denmark)

    Mollerup, Ane Loft; Mikkelsen, Peter Steen; Thornberg, Dines

    2015-01-01

    . To this end, four distinct modes of operation are identified (dry weather, filling, saturation and emptying) and for each of these the process gain matrix is found. Based on the gain matrices a controllability analysis is performed, to screen for suitable pairings between measurements and actuators......A systematic methodology for regulatory control analysis and design is adapted for sewer system operation and evaluated. The main challenge with adapting the methodology is the handling of the stochastic and transient nature of the rainfall disturbances, inherent to sewer system operation...... in the case study area of Copenhagen. The analysis effectively reduces the number of potential controlled variables, by considering the sensitivity of the measurements towards changes in the manipulated variables. Several potential pairings are generated and the best alternative is chosen for closed...

  3. Quality of local control for simple sewer networks

    Science.gov (United States)

    Kolechkina, Alla; van Nooijen, Ronald

    2016-04-01

    Combined sewer networks, where both foul water and storm water are transported through the same system, tend to develop into complex networks due to expansion of towns and villages. The transport capacity of these systems is always limited, so occasional controlled spills into surface water, combined sewer overflows (CSO), are part of the normal operating procedure. Occasionally the ideas and rules present in the original design are not respected when the system is extended to cover a larger area. One way to deal with this problem is to implement central control. Another is to add pipes and hardware to bring the extended system into line with the original rules and ideas. We show that for a design rule often followed in the Netherlands, local control does quite well as long as the rule is respected and there are no large variations in precipitation intensity over the area covered by the system.

  4. A software-based sensor for combined sewer overflows.

    Science.gov (United States)

    Leonhardt, G; Fach, S; Engelhard, C; Kinzel, H; Rauch, W

    2012-01-01

    A new methodology for online estimation of excess flow from combined sewer overflow (CSO) structures based on simulation models is presented. If sufficient flow and water level data from the sewer system is available, no rainfall data are needed to run the model. An inverse rainfall-runoff model was developed to simulate net rainfall based on flow and water level data. Excess flow at all CSO structures in a catchment can then be simulated with a rainfall-runoff model. The method is applied to a case study and results show that the inverse rainfall-runoff model can be used instead of missing rain gauges. Online operation is ensured by software providing an interface to the SCADA-system of the operator and controlling the model. A water quality model could be included to simulate also pollutant concentrations in the excess flow.

  5. Oxidation and Precipitation of Sulfide in Sewer Networks

    DEFF Research Database (Denmark)

    Nielsen, A. H.

    wastewater and biofilms of sewer networks was studied in detail with emphasis on determination of process kinetics and stoichiometry. In the water phase, sulfide oxidation may be both chemical and biological and the investigations showed that both processes were of significant importance in the sulfur cycle...... transformations. The experiments indicated that biological sulfide oxidation in the water phase and sulfide oxidation by sewer biofilms produce elemental sulfur under the conditions investigated. The stoichiometry of chemical sulfide oxidation was apparently more complex producing both thiosulfate and sulfate......-workers at Aalborg University for more than a decade. In the basic version, the WATS model simulates changes in dissolved oxygen (DO) and organic fractions of different biodegradability under both aerobic and anaerobic conditions. Evaluation of the model concept has demonstrated that it can be successfully...

  6. Aerobic and anaerobic transformations of sulfide in a sewer system--field study and model simulations.

    Science.gov (United States)

    Nielsen, Asbjørn Haaning; Vollertsen, Jes; Jensen, Henriette Stokbro; Madsen, Heidi Ina; Hvitved-Jacobsen, Thorkild

    2008-01-01

    The formation and fate of sulfide in a force main and a downstream-located gravity sewer were investigated in an extensive field study. Sulfide formation in the force main was significant. However, during 14 minutes of transport in the gravity sewer, the sulfide concentration decreased 30%, on average. An application of a conceptual sewer process model for simulating the formation and fate of sulfide was demonstrated. Overall, the model predicted that approximately 90% of the decrease of the sulfide concentration in the gravity sewer was the result of sulfide oxidation and that only a small fraction entered the sewer atmosphere, causing odor and corrosion. Even so, the model predicted concrete corrosion rates of up to 1.2 mm/y in the gravity sewer section.

  7. [Pollutant source apportionment of combined sewer overflows using chemical mass balance method].

    Science.gov (United States)

    Dai, Mei-Hong; Li, Tian; Zhang, Wei

    2013-11-01

    Pollutant characteristics of surface runoff, sanitary sewage and sewer deposits from a combined sewer system in Shanghai were studied. It was confirmed that the content of Zn, NH4(+) -N, P, respectively in surface runoff, sanitary sewage and sewer deposits was specific and relatively stable based on contrasting pollutant characteristics of different sources. Three non-dimensional parameters-Zn/P, NH4(+) -N/Zn, P/K were proposed as characteristic index for surface runoff, sanitary sewage and sewer deposits. In order to find sources of pollutants in CSO, the application of chemical mass balance method was discussed: the average contributions to CSO were 42.8% for surface runoff, 12.2% for sanitary sewage, 23.8% for sewer deposits, and the results basically reflected the composition of CSO pollution. The research method and results can provide guidance for pollutant source apportionment of combined sewer overflows.

  8. Life cycle assessment of urban wastewater systems: Quantifying the relative contribution of sewer systems.

    Science.gov (United States)

    Risch, Eva; Gutierrez, Oriol; Roux, Philippe; Boutin, Catherine; Corominas, Lluís

    2015-06-15

    This study aims to propose a holistic, life cycle assessment (LCA) of urban wastewater systems (UWS) based on a comprehensive inventory including detailed construction and operation of sewer systems and wastewater treatment plants (WWTPs). For the first time, the inventory of sewers infrastructure construction includes piping materials and aggregates, manholes, connections, civil works and road rehabilitation. The operation stage comprises energy consumption in pumping stations together with air emissions of methane and hydrogen sulphide, and water emissions from sewer leaks. Using a real case study, this LCA aims to quantify the contributions of sewer systems to the total environmental impacts of the UWS. The results show that the construction of sewer infrastructures has an environmental impact (on half of the 18 studied impact categories) larger than both the construction and operation of the WWTP. This study highlights the importance of including the construction and operation of sewer systems in the environmental assessment of centralised versus decentralised options for UWS.

  9. Model-based analysis of control performance in sewer systems

    DEFF Research Database (Denmark)

    Mollerup, Ane Høyer; Mauricio Iglesias, Miguel; Johansen, N.B.;

    2012-01-01

    Design and assessment of control in wastewater systems has to be tackled at all levels, including supervisory and regulatory level. We present here an integrated approach to assessment of control in sewer systems based on modelling and the use of process control tools to assess the controllability...... of the process. A case study of a subcatchment area in Copenhagen (Denmark) is used to illustrate the combined approach in modelling of the system and control assessment....

  10. South Davis Sewer District Pump Station Hydraulic Capacity Evaluation

    OpenAIRE

    Dixon, James W

    2011-01-01

    In 2010, South Davis Sewer District (SDSD) determined that possible hydraulic problems existed in their various pump stations operating within their treatment plants. A hydraulic analysis was conducted for the pump stations to diagnose the problems and provide possible alternative solutions. This analysis was conducted by using hydraulic minor loss equations to determine the amount of flow that the pumps were capable of producing and then comparing those results to the required demands in the...

  11. Worcester Municipal Separate Storm Sewer System (MS4) ...

    Science.gov (United States)

    2017-04-10

    Worcester was issued NPDES Permit MAS010002 for discharging storm water from its municipal separate storm sewer system (MS4) which became effective on October 30, 1998. The permit expired five years later on October 30, 2003; however, EPA administratively continued the permit as allowed by regulation. Proceeding to reissue this NPDES permit, EPA and MassDEP have now issued a draft permit and fact sheet (which provides EPA's technical basis for establishing permit conditions).

  12. Investigation of sewer exfiltration using integral pumping tests and wastewater indicators

    Science.gov (United States)

    Leschik, Sebastian; Musolff, Andreas; Martienssen, Marion; Krieg, Ronald; Bayer-Raich, Marti; Reinstorf, Frido; Strauch, Gerhard; Schirmer, Mario

    2009-11-01

    Leaky sewers affect urban groundwater by the exfiltration of untreated wastewater. However, the impact of sewer exfiltration on the groundwater is poorly understood. Most studies on sewer exfiltration focus on water exfiltration, but not on the impact on groundwater quality. In this paper we present a new monitoring approach to estimate mass flow rates Mex of different wastewater indicators (WWIs) from leaky sewers by applying integral pumping tests (IPTs). The problem of detecting and assessing heterogeneous concentrations in the vicinity of leaky sewers can be overcome with the IPT approach by the investigation of large groundwater volumes up- and downstream of leaky sewers. The increase in concentrations downstream of a leaky sewer section can be used to calculate Mex with a numerical groundwater model. The new monitoring approach was first applied using four IPT wells in Leipzig (Germany). Over a pumping period of five days we sampled five inorganic WWIs: B , Cl -, K +, NO 3-, NH 4+ and three xenobiotics: bisphenol-a, caffeine and tonalide. The resulting concentration-time series indicated an influence of wastewater at one IPT well downstream of the leaky sewer. We defined ranges of Mex by implementing the uncertainty of chemical analyses. The results showed a Mex of 0-10.9 g m - 1 d - 1 . The combination of Mex with wastewater concentrations from the target sewer yielded an exfiltration rate Qex of 28.0-63.9 L m - 1 d - 1 for the conservative ion Cl -. Most non-conservative WWIs showed reduced mass flow rates in the groundwater downstream of the leaky sewer that indicate a mass depletion during their passage from the sewer to the pumping well. Application of the IPT methodology at other field sites is possible. The IPT monitoring approach provides reliable Mex values that can help to assess the impact of leaky sewers on groundwater.

  13. Successful Municipal Separate Storm Sewer System Programs Implemented in the Navy - NESDI #494

    Science.gov (United States)

    2014-06-01

    2014 SUCCESSFUL MUNICIPAL SEPARATE STORM SEWER SYSTEM PROGRAMS IMPLEMENTED IN THE NAVY—NESDI #494 Prepared by: Edwin Chiang, P.E...SUBTITLE 5a. CONTRACT NUMBER SUCCESSFUL MUNICIPAL SEPARATE STORM SEWER SYSTEM PROGRAMS IMPLEMENTED IN THE NAVY—PROJECT #494 5b. GRANT NUMBER...installations as lessons learned for complying with municipal separate storm sewer system (MS4) regulatory requirements. An evaluation of business practices

  14. An approach to pathogens flux simulation in a combined sewer system

    OpenAIRE

    Breil, P.; Petit, S.; Boukerb, A.; Namour, P.; McCarthy, D; Cournoyer, B

    2013-01-01

    International audience; Combined sewer systems convey organic matters and pathogens coming from human and animal faeces. They are mixed with rainfall runoff during storm event and can overflows to natural aquatic systems. Preliminary genetic analyses of pathogens were conducted in an experimental small water course and its lateral combined sewer system (OTHU site). Results indicate that natural system pathogens are an evolution of sewer system pathogens. However their presumed survival should...

  15. Impact of water source management practices in residential areas on sewer networks - a review.

    Science.gov (United States)

    Marleni, N; Gray, S; Sharma, A; Burn, S; Muttil, N

    2012-01-01

    Prolonged drought which has occurred everywhere around the world has caused water shortages, leading many countries to consider more sustainable practices, which are called source management practices (SMPs) to ensure water availability for the future. SMPs include the practices of water use reduction, potable water substitution and wastewater volume reduction such as water demand management, rainwater harvesting, greywater recycling and sewer mining. Besides the well known advantages from SMPs, they also contribute to the alteration of wastewater characteristics which finally affect the process in downstream infrastructure such as sewerage networks. Several studies have shown that the implementation of SMPs decreases the wastewater flow, whilst increasing its strength. High-strength wastewater can cause sewer problems such as sewer blockage, odour and corrosion. Yet, not all SMPs and their impact on existing sewer networks have been investigated. Therefore, this study reviews some examples of four common SMPs, the wastewater characteristics and the physical and biochemical transformation processes in sewers and the problems that might caused by them, and finally the potential impacts of those SMPs on wastewater characteristics and sewer networks are discussed. This paper provides sewer system managers with an overview of potential impacts on the sewer network due to the implementation of some SMPs. Potential research opportunities for the impact of SMPs on existing sewers are also identified.

  16. Impact of sewage treatment plants and combined sewer overflow basins on the microbiological quality of surface water.

    Science.gov (United States)

    Rechenburg, A; Koch, Ch; Classen, Th; Kistemann, Th

    2006-01-01

    In a small river catchment, microbiological quality of different sewage treatment plants under regular conditions and in case of heavy rainfall, when combined sewage overflow basins (CSOs) are activated, was examined regarding microbial indicators and pathogens. In the watercourse, no self-cleaning effects could be observed. Small compact treatment plants discharge treated wastewater with a poor microbiological quality compared to river water quality and the quality of treated wastewater of larger plants. During storm water events, concentrations of microorganisms downstream of sewer overflows were approximately two logs higher than during dry weather conditions. Concentrations of parasites decreased slowly during the overflow, in parallel to filterable matter and particle-bound substances. The annual load of microorganisms originating from CSOs significantly exceeds the load from treated effluent of the sewage plants. Thus, an improved hygienic quality of the water course could be achieved by preventing overflows and by enhancing sewage treatment plants.

  17. Design and performance evaluation of a simplified dynamic model for combined sewer overflows in pumped sewer systems

    Science.gov (United States)

    van Daal-Rombouts, Petra; Sun, Siao; Langeveld, Jeroen; Bertrand-Krajewski, Jean-Luc; Clemens, François

    2016-07-01

    Optimisation or real time control (RTC) studies in wastewater systems increasingly require rapid simulations of sewer systems in extensive catchments. To reduce the simulation time calibrated simplified models are applied, with the performance generally based on the goodness of fit of the calibration. In this research the performance of three simplified and a full hydrodynamic (FH) model for two catchments are compared based on the correct determination of CSO event occurrences and of the total discharged volumes to the surface water. Simplified model M1 consists of a rainfall runoff outflow (RRO) model only. M2 combines the RRO model with a static reservoir model for the sewer behaviour. M3 comprises the RRO model and a dynamic reservoir model. The dynamic reservoir characteristics were derived from FH model simulations. It was found that M2 and M3 are able to describe the sewer behaviour of the catchments, contrary to M1. The preferred model structure depends on the quality of the information (geometrical database and monitoring data) available for the design and calibration of the model. Finally, calibrated simplified models are shown to be preferable to uncalibrated FH models when performing optimisation or RTC studies.

  18. Tendon repair

    Science.gov (United States)

    Repair of tendon ... Tendon repair can be performed using: Local anesthesia (the immediate area of the surgery is pain-free) ... a cut on the skin over the injured tendon. The damaged or torn ends of the tendon ...

  19. Association between Gastrointestinal Illness and Precipitation in Areas Impacted by Combined Sewer Systems: Utilizing a Distributed Lag Model

    Science.gov (United States)

    Combined sewer systems collect rainwater runoff, sewage, and industrial wastewater for transit to treatment facilities. With heavy precipitation, volumes can exceed capacity of treatment facilities, and wastewater discharges directly to receiving waters. These combined sewer over...

  20. Sanitary Sewer Systems and Association with Gastrointestinal Illness: A case crossover analysis of Massachusetts Data, 2006-2008

    Science.gov (United States)

    Sanitary sewer overflows (SSOs) occur when untreated sewage is discharged into water sources before reaching the treatment facility potentially contaminating them with gastrointestinal pathogens. Causes of SSOs include heavy rainfall and rupture/blockage of sewer lines. Few studi...

  1. PIPEGUARD - A novel technology for sewerage mapping, inspection and cleaning with integrated real-time self-audit capability: Final Report Summary

    OpenAIRE

    Eicher, Frank

    2014-01-01

    Sewage systems are crucial to reduce the risks of water borne diseases and avoid flooding of cities. Cleaning processes are thus highly important to avoid health risks and environmental, economic and societal impacts which can be caused by damaged or blocked sewerage. Sewer networks must therefore not only be kept clean, they also have to be continuously inspected in order to detect structural damages, pipe deterioration and construction failures in order to avoid local city floods, backflow ...

  2. Catchment & sewer network simulation model to benchmark control strategies within urban wastewater systems

    DEFF Research Database (Denmark)

    Saagi, Ramesh; Flores Alsina, Xavier; Fu, Guangtao

    2016-01-01

    This paper aims at developing a benchmark simulation model to evaluate control strategies for the urban catchment and sewer network. Various modules describing wastewater generation in the catchment, its subsequent transport and storage in the sewer system are presented. Global/local overflow bas...

  3. Flood Grouting for Infiltration Reduction on Private Side Sewers (WERF Report INFR5R11)

    Science.gov (United States)

    The sewers in Seattle’s Broadview neighborhood, built in the 1950s, experience significant inflow and infiltration. Intense wet weather events have resulted in sewer overflows into private residences and the environment and previous work indicates that the majority of this excess...

  4. The Characteristics of Waste Water Flow in a Danish Combined Sewer

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Rasmussen, Michael R.

    2004-01-01

    have been analysed in order to extract some of their characteristics. Furthermore it is emphasised that the presence of a self-cleansing capacity of a combined sewer system is of vital importance in order to reduce the impact of combined sewer overflows on receiving waters. Whether or not the pipelines...

  5. Leveraging existing infrastructure for central automatic control of multiple sewer systems

    NARCIS (Netherlands)

    Van Loenen, A.; Van Heeringen, K.J.; Van Nooyen, R.R.P.; Van Velzen, E.

    2012-01-01

    In this paper we discuss a project in which water quality improvements of surface waters are gained by upgrading locally controlled sewer systems. The paper focuses on the reuse and extension of existing sewer systems and hardware and software infrastructure in an experimental integrated automatic

  6. Growth kinetics of hydrogen sulfide oxidizing bacteria in corroded concrete from sewers

    NARCIS (Netherlands)

    Jensen, H.S.; Lens, P.N.L.; Nielsen, J.L.; Bester, K.; Nielsen, A.H.; Hvitved-Jacobsen, Th.; Vollertsen, J.

    2011-01-01

    Hydrogen sulfide oxidation by microbes present on concrete surfaces of sewer pipes is a key process in sewer corrosion. The growth of aerobic sulfur oxidizing bacteria from corroded concrete surfaces was studied in a batch reactor. Samples of corrosion products, containing sulfur oxidizing bacteria,

  7. Flood Grouting for Infiltration Reduction on Private Side Sewers (WERF Report INFR5R11)

    Science.gov (United States)

    The sewers in Seattle’s Broadview neighborhood, built in the 1950s, experience significant inflow and infiltration. Intense wet weather events have resulted in sewer overflows into private residences and the environment and previous work indicates that the majority of this excess...

  8. THE ANALYSIS OF THE COSTS AND THE CORRELATION BETWEEN TARIFF AND COST IN THE SECTOR OF CLEAN WATER AND SEWERAGE IN ROMANIA

    Directory of Open Access Journals (Sweden)

    FÜLÖP ÁRPÁD-ZOLTÁN

    2017-08-01

    Full Text Available The analysis of the costs and of the structure of tariffs for operators in the sector of water and sewage system in Romania are a real challenge. Through this analysis we can form an overview of the costs which may involve in the service of providing clean water and the sewage and wastewater treatment. The costs is analysed both in the cost structure at the enterprise level and in comparison with the income made from the activity (supply of drinking water or treatment of wastewater. In the article we study the cost structure at the level of sector of activity and the correlation between the tariff applied to water and sewer services and size of enterprise, number of employees, wage costs, maintenance and repair costs, energy cost and other variables. The correlations results helps us to make the first steps for the realization of an equation of the cost at the level of the sector of water and sewage system. Another correlation study will be between the applied tariff and the size of the investments made with european co-financing in the framework of the SOP Environment. Through this correlation we determine if the size of the tariffs applied in this sector correlate to the size of the investments made in the SOP Environment.

  9. Flooding in urban drainage systems: Coupling hyperbolic conservation laws for sewer systems and surface flow

    CERN Document Server

    Borsche, Raul

    2014-01-01

    In this paper we propose a model for a sewer network coupled to surface flow and investigate it numerically. In particular, we present a new model for the manholes in storm sewer systems. It is derived using the balance of the total energy in the complete network. The resulting system of equations contains, aside from hyperbolic conservation laws for the sewer network and algebraic relations for the coupling conditions, a system of ODEs governing the flow in the manholes. The manholes provide natural points for the interaction of the sewer system and the run off on the urban surface modelled by shallow water equations. Finally, a numerical method for the coupled system is presented. In several numerical tests we study the influence of the manhole model on the sewer system and the coupling with 2D surface flow.

  10. Prioritizing sewer rehabilitation projects using AHP-PROMETHEE II ranking method.

    Science.gov (United States)

    Kessili, Abdelhak; Benmamar, Saadia

    2016-01-01

    The aim of this paper is to develop a methodology for the prioritization of sewer rehabilitation projects for Algiers (Algeria) sewer networks to support the National Sanitation Office in its challenge to make decisions on prioritization of sewer rehabilitation projects. The methodology applies multiple-criteria decision making. The study includes 47 projects (collectors) and 12 criteria to evaluate them. These criteria represent the different issues considered in the prioritization of the projects, which are structural, hydraulic, environmental, financial, social and technical. The analytic hierarchy process (AHP) is used to determine weights of the criteria and the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE II) method is used to obtain the final ranking of the projects. The model was verified using the sewer data of Algiers. The results have shown that the method can be used for prioritizing sewer rehabilitation projects.

  11. Simulation of sulfide buildup in wastewater and atmosphere of sewer networks.

    Science.gov (United States)

    Nielsen, A H; Yongsiri, C; Hvitved-Jacobsen, T; Vollertsen, J

    2005-01-01

    A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to--and a further development of--the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.

  12. Bladder exstrophy repair

    Science.gov (United States)

    Bladder birth defect repair; Everted bladder repair; Exposed bladder repair; Repair of bladder exstrophy ... Bladder exstrophy repair involves two surgeries. The first surgery is to repair the bladder and the second one is to attach ...

  13. 一种新型排水管道在线检测设备的设计%Design of a New Kind of Online Detection Equipment in Sewer Pipes

    Institute of Scientific and Technical Information of China (English)

    李怀正; 柏蔚; 邱平平; 刘振华

    2013-01-01

      指出了随着城镇化进程的不断深入,中国城镇的排水管网规模不断扩大,一系列的排水管道问题也暴露在公众面前,使城市排水管道检测技术急需进行变革。国内目前缺乏一种经济实用、方便可行的排水管道检测设备来快速有效地诊断排水管道症结,基于此,设计了一种新性排水管道在线监测设备,该设备集成了国内外优秀技术的模块,具有成像清晰、使用方便、运行稳定的特点,同时还具有测量管道沉积物厚度以及高压水清洗管道的实用功能。%With the furthering process of urbanization and the enlarging scale of Chinese urban drainage pipes ,a series of problems caused by sewers come into public view ,which impels sewer detection technologies to change .However ,there is no such an economic ,convenient and feasible sewer detection equipment to quickly respond to sewer syndrome in China .In this case ,the authors of this study have developed a new kind of online detection equipment w hich encompasses the advanced modules from home and abroad based on this .And now it has the properties of clear visibility ,convenience in use and stability .Also ,it has the practi-cal functions of measuring sewer sediment depth and cleaning pipes with high pressure .

  14. Detention storage volume for combined sewer overflow into a river.

    Science.gov (United States)

    Temprano, J; Tejero, I

    2002-06-01

    This article discusses the storage volume needed in a combined sewer system tank in order to preserve the water quality. There are a lot of design criteria which do not take into account the conditions of the receiving water, and as a result are inappropriate. A model was used to simulate the performance of a theoretical combined sewer system where a tank was located downstream. Results were obtained from the overflows produced by the rain recorded in Santander (Spain) for 11 years, with several combinations of storage volume and treatment capacity in the wastewater treatment plant. Quality criteria were also proposed for faecal coliforms, BOD, and total nitrogen to evaluate the effects from the overflows in the river water quality. Equations have been obtained which relate the number of overflows, the storage volume and the treatment plant capacity. The bacteriological pollution, quantified by means of faecal coliforms, was the analytical parameter which produced the most adverse effects in the river, so that more storage volume is needed (45 to 180 m3 ha(-1) net) than with other simulated pollutants (5 to 50 m3 ha(-1) net for BOD, and less than 4 m3 ha(-1) net for the total nitrogen). The increase in the treatment plant's capacity, from two to three times the flow in dry weather, reduces the impact on the river water in a more effective way, allowing a reduction of up to 65% in the number of overflows rather than increasing the storage volume.

  15. Urban flood risk assessment using sewer flooding databases.

    Science.gov (United States)

    Caradot, Nicolas; Granger, Damien; Chapgier, Jean; Cherqui, Frédéric; Chocat, Bernard

    2011-01-01

    Sustainable water management is a global challenge for the 21st century. One key aspect remains protection against urban flooding. The main objective is to ensure or maintain an adequate level of service for all inhabitants. However, level of service is still difficult to assess and the high-risk locations difficult to identify. In this article, we propose a methodology, which (i) allows water managers to measure the service provided by the urban drainage system with regard to protection against urban flooding; and (ii) helps stakeholders to determine effective strategies for improving the service provided. One key aspect of this work is to use a database of sewer flood event records to assess flood risk. Our methodology helps urban water managers to assess the risk of sewer flooding; this approach does not seek to predict flooding but rather to inform decision makers on the current level of risk and on actions which need to be taken to reduce the risk. This work is based on a comprehensive definition of risk, including territorial vulnerability and perceptions of urban water stakeholders. This paper presents the results and the methodological contributions from implementing the methodology on two case studies: the cities of Lyon and Mulhouse.

  16. Advanced maintenance, inspection & repair technology for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hinton, B.M.

    1994-12-31

    Maintenance, inspection, and repair technology for nuclear power plants is outlined. The following topics are discussed: technology for reactor systems, reactor refueling bridge, fuel inspection system, fuel shuffling software, fuel reconstitution, CEA/RCCA/CRA inspection, vessel inspection capabilities, CRDM inspection and repair, reactor internals inspection and repair, stud tensioning system, stud/nut cleaning system, EDM machining technology, MI Cable systems, core exit T/C nozzle assemblies, technology for steam generators, genesis manipulator systems, ECT, UT penetrant inspections, steam generator repair and cleaning systems, technology for balance of plant, heat exchangers, piping and weld inspections, and turbogenerators.

  17. Modeling Sulfides, pH and Hydrogen Sulfide Gas in the Sewers of San Francisco.

    Science.gov (United States)

    Vollertsen, Jes; Revilla, Nohemy; Hvitved-Jacobsen, Thorkild; Nielsen, Asbjørn Haaning

    2015-11-01

    An extensive measuring campaign targeted on sewer odor problems was undertaken in San Francisco. It was assessed whether a conceptual sewer process model could reproduce the measured concentrations of total sulfide in the wastewater and H2S gas in the sewer atmosphere, and to which degree such simulations have potential for further improving odor and sulfide management. The campaign covered measurement of wastewater sulfide by grab sampling and diurnal sampling, and H2S gas in the sewer atmosphere was logged. The tested model was based on the Wastewater Aerobic/Anaerobic Transformations in Sewers (WATS) sewer process concept, which never had been calibrated to such an extensive dataset. The study showed that the model was capable of reproducing the general levels of wastewater sulfide, wastewater pH, and sewer H2S gas. It could also reproduce the general variability of these parameters, albeit with some uncertainty. It was concluded that the model could be applied for the purpose in mind.

  18. The Ecology of Acidophilic Microorganisms in the Corroding Concrete Sewer Environment.

    Science.gov (United States)

    Li, Xuan; Kappler, Ulrike; Jiang, Guangming; Bond, Philip L

    2017-01-01

    Concrete corrosion is one of the most significant problems affecting valuable sewer infrastructure on a global scale. This problem occurs in the aerobic zone of the sewer, where a layer of surface corrosion develops on the exposed concrete and the surface pH is typically lowered from around 11-10 (pristine concrete) to pH 2-4. Acidophilic microorganisms become established as biofilms within the concrete corrosion layer and enhance the loss of concrete mass. Until recently, the acidophilic community was considered to comprise relatively few species of microorganisms, however, the biodiversity of the corrosion community is now recognized as being extensive and varying from different sewer environmental conditions. The diversity of acidophiles in the corrosion communities includes chemolithoautotrophs, chemolithoheterotrophs, and chemoorganoheterotrophs. The activity of these microorganisms is strongly affected by H2S levels in the sewer gas phase, although CO2, organic matter, and iron in the corrosion layer influence this acidic ecosystem. This paper briefly presents the conditions within the sewer that lead to the development of concrete corrosion in that environment. The review focuses on the acidophilic microorganisms detected in sewer corrosion environments, and then summarizes their proposed functions and physiology, especially in relation to the corrosion process. To our knowledge, this is the first review of acidophilic corrosion microbial communities, in which, the ecology and the environmental conditions (when available) are considered. Ecological studies of sewer corrosion are limited, however, where possible, we summarize the important metabolic functions of the different acidophilic species detected in sewer concrete corrosion layers. It is evident that microbial functions in the acidic sewer corrosion environment can be linked to those occurring in the analogous acidic environments of acid mine drainage and bioleaching.

  19. Principles and approaches for numerical modelling of sediment transport in sewers

    DEFF Research Database (Denmark)

    Mark, Ole; Larsen, Torben; Appelgren, Cecilia

    1994-01-01

    A study has been carried out at the University of Aalborg, Denmark and VBB VIAK, Sweden with the objectives to describe the effect of sediment deposits on the hydraulic capacity of sewer systems and to investigate the sediment transport in sewer systems. A results of the study is a mathematical...... model MOUSE ST which describes the sediment transport in sewers. This paper discusses the applicability and the limitations of various modelling approaches and sediment transport formulations in MOUSE ST. The study was founded by the Swedish Water and Waste Works Association and the Nordic Industrial...

  20. Sediment Transport Model For Storm Sewer Networks Towards The Operational Risks

    Directory of Open Access Journals (Sweden)

    I. RÁTKY

    2016-11-01

    Full Text Available Sediment transport in sewer networks can be critical in economical and safety point of view. To improve the operation of the sewer networks we are presenting a model, which is capable of numerical simulations of the sediment transport in storm water network. The developed model is calculating the change of the particle distribution of the sediment fractions including the effects of settling and mixing up processes. The results of the model calculations in a simplified network are also presented. We are also planning to apply the developed sediment transport module by coupling to a hydrodynamic simulation for practical tasks supporting the design and operation of sewers networks.

  1. Coordinated management of combined sewer overflows by means of advanced environmental decision support systems

    DEFF Research Database (Denmark)

    Murla, Damian; Gutierrez, Oriol; Martinez, Montse

    2016-01-01

    been tested in a specially designed virtual UWS, including two sewers systems, two WWTP and one river subjected to typical Mediterranean rain conditions. Results show that sewer systems, retention tanks and wastewater treatment plants improve their performance under wet weather conditions and that EDSS......During heavy rainfall, the capacity of sewer systems and wastewater treatment plants may be surcharged producing uncontrolled wastewater discharges and a depletion of the environmental quality. Therefore there is a need of advanced management tools to tackle with these complex problems...

  2. Principles and Approaches for Numerical Modelling of Sediment Transport in Sewers

    DEFF Research Database (Denmark)

    Mark, Ole; Appelgren, Cecilia; Larsen, Torben

    1995-01-01

    A study has been carried out with the objectives of describing the effect of sediment deposits on the hydraulic capacity of sewer systems and to investigate the sediment transport in sewer systems. A result of the study is a mathematical model MOUSE ST which describes sediment transport in sewers....... This paper discusses the applicability and the limitations of various modelling approaches and sediment transport formulations in in MOUSE ST. Further, the paper presents a simple application of MOUSE ST to the Rya catchment in Gothenburg, Sweden....

  3. Real-time control of sewer systems using turbidity measurements.

    Science.gov (United States)

    Lacour, C; Schütze, M

    2011-01-01

    Real-time control (RTC) of urban drainage systems has been proven useful as a means to reduce pollution by combined sewer overflow discharges. So far, RTC has been investigated mainly with a sole focus on water quantity aspects. However, as measurement techniques for pollution of wastewater are advancing, pollution-based RTC might be of increasing interest. For example, turbidity data sets from an extensive measurement programme in two Paris catchments allow a detailed investigation of the benefits of using pollution-based data for RTC. This paper exemplifies this, comparing pollution-based RTC with flow-based RTC. Results suggest that pollution-based RTC indeed has some potential, particularly when measurements of water-quality characteristics are readily available.

  4. Gamma and beta logging of underground sewer and process lines

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, M.J.; Martz, D.E.; Langner, G.H. Jr.

    1989-11-01

    The GammaSnake can be useful for locating uranium mill tailings used as backfill for sewer lines or storm drains where the lines can be readily accessed from a cleanout access port or other opening. The time required to determine if contamination is present using the GammaSnake method is considerably less than when using the delta gamma or drilling methods. There is, also, less potential hazard to the equipment operators when using the GammaSnake method. The GammaSnake method is generally limited to a distance of 100 feet or less. Used with the MAC-51B line locator, the GammaSnake method can provide useful information without extensive drilling or surveying. 7 figs., 2 tabs.

  5. Critical velocity of floatables in combined sewer overflow (CSO) chambers.

    Science.gov (United States)

    Cigana, J; Lefebvre, G; Marche, C

    2001-01-01

    Although the efficiency of underflow baffles has never been clearly proven, these underflow baffles have gained in popularity over the last few years as a viable means to intercept floatables in Combined Sewer Overflows (CSOs). These pilot scale essays, performed in a 17.0 metres basin at various flowrates, show that a critical horizontal velocity (V(CR)) may develop in the overflow chamber. Whenever this critical velocity is exceeded, floatables that would normally rise to the surface are kept within the flow and never intercepted, thus rendering the underflow baffle ineffective. The equation relating the critical horizontal velocity to the vertical velocity is found to be: V(CR) = 16 w R(H) 1/6.

  6. A framework for optimal reliability-based storm sewer network design in flat areas

    National Research Council Canada - National Science Library

    Haghighi, Ali; Samani, Hossein Mohammad Vali; Moussavi, Ali

    .... The model offers numerous design alternatives with various levels of reliability. The model was successfully applied to the Kianpars storm sewer network, a flat district of the city of Ahvaz in Iran...

  7. Modelling Illicit Drug Fate in Sewers for Wastewater-Based Epidemiology

    DEFF Research Database (Denmark)

    Ramin, Pedram

    . After transport in sewers, these chemicals enter wastewater treatment plants (WWTPs). Monitoring campaigns are normally performed at WWTP influent to collect representative samples. Following quantitative chemical analysis, measured drug loads are used to estimate population-normalized parent drug......, are subject to physical, chemical or biological processes in sewers (fate processes). The occurrence of these processes may lead to significant change of drug loads at WWTP influent compared to source release points. Therefore, not accounting for these variations may negatively affect drug use estimates....... Sewer systems can be considered as biological reactors, in which the concentration of organic chemicals present in wastewater can be impacted by in-sewer processes during hydraulic residence time. Illicit drug biomarkers, as trace organic chemicals in the range of nanograms to micrograms per liter...

  8. Sewerage Collection Lines, Sewer Lines, Published in unknown, North Georgia College and State University.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Sewerage Collection Lines dataset, was produced all or in part from Field Survey/GPS information as of unknown. It is described as 'Sewer Lines'. Data by this...

  9. Sewerage Treatment Plants, Sewer Treatment Plant, Published in 2008, City of Elizabeth City.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Sewerage Treatment Plants dataset, was produced all or in part from Orthoimagery information as of 2008. It is described as 'Sewer Treatment Plant'. Data by...

  10. Design Of A Laboratory Set-up For Evaluating Structural Strength Of Deteriorated Concrete Sewer Pipes

    NARCIS (Netherlands)

    Stanic, N.; Salet, T.; Langeveld, J.G.; Clemens, F.H.L.R.

    2014-01-01

    The principle of structural behaviour of buried concrete pipes is fairly understood, except for how material deterioration affects structural behaviour and performance. Consequently, information on the structural behaviour of deteriorated sewer pipes will contribute to better understanding of the ch

  11. Predicting the Probability of Failure of Cementitious Sewer Pipes Using Stochastic Finite Element Method.

    Science.gov (United States)

    Alani, Amir M; Faramarzi, Asaad

    2015-06-10

    In this paper, a stochastic finite element method (SFEM) is employed to investigate the probability of failure of cementitious buried sewer pipes subjected to combined effect of corrosion and stresses. A non-linear time-dependant model is used to determine the extent of concrete corrosion. Using the SFEM, the effects of different random variables, including loads, pipe material, and corrosion on the remaining safe life of the cementitious sewer pipes are explored. A numerical example is presented to demonstrate the merit of the proposed SFEM in evaluating the effects of the contributing parameters upon the probability of failure of cementitious sewer pipes. The developed SFEM offers many advantages over traditional probabilistic techniques since it does not use any empirical equations in order to determine failure of pipes. The results of the SFEM can help the concerning industry (e.g., water companies) to better plan their resources by providing accurate prediction for the remaining safe life of cementitious sewer pipes.

  12. Airing 'clean air' in Clean India Mission.

    Science.gov (United States)

    Banerjee, T; Kumar, M; Mall, R K; Singh, R S

    2017-03-01

    The submission explores the possibility of a policy revision for considering clean air quality in recently launched nationwide campaign, Clean India Mission (CIM). Despite of several efforts for improving availability of clean household energy and sanitation facilities, situation remain still depressing as almost half of global population lacks access to clean energy and proper sanitation. Globally, at least 2.5 billion people do not have access to basic sanitation facilities. There are also evidences of 7 million premature deaths by air pollution in year 2012. The situation is even more disastrous for India especially in rural areas. Although, India has reasonably progressed in developing sanitary facilities and disseminating clean fuel to its urban households, the situation in rural areas is still miserable and needs to be reviewed. Several policy interventions and campaigns were made to improve the scenario but outcomes were remarkably poor. Indian census revealed a mere 31% sanitation coverage (in 2011) compared to 22% in 2001 while 60% of population (700 million) still use solid biofuels and traditional cook stoves for household cooking. Further, last decade (2001-2011) witnessed the progress decelerating down with rural households without sanitation facilities increased by 8.3 million while minimum progress has been made in conversion of conventional to modern fuels. To revamp the sanitation coverage, an overambitious nationwide campaign CIM was initiated in 2014 and present submission explores the possibility of including 'clean air' considerations within it. The article draws evidence from literatures on scenarios of rural sanitation, energy practises, pollution induced mortality and climatic impacts of air pollution. This subsequently hypothesised with possible modification in available technologies, dissemination modes, financing and implementation for integration of CIM with 'clean air' so that access to both sanitation and clean household energy may be

  13. Hypospadias repair

    Science.gov (United States)

    ... the problem. If the repair is not done, problems may occur later on such as: Difficulty controlling and directing urine stream A curve in the penis during erection Decreased fertility Embarrassment about appearance of penis Surgery ...

  14. Biodegradability of organic matter associated with sewer sediments during first flush.

    OpenAIRE

    Sakrabani, R.; Vollertsen, J.; Ashley, R.M.; Hvitved-Jacobsen, T.

    2009-01-01

    The high pollution load in wastewater at the beginning of a rain event is commonly known to originate from the erosion of sewer sediments due to the increased flow rate under storm weather conditions. It is essential to characterize the biodegradability of organic matter during a storm event in order to quantify the effect it can have further downstream to the receiving water via discharges from Combined Sewer Overflow (CSO). The approach is to characterize the pollutograph during first flush...

  15. Towards better management of combined sewer systems. A methodology based on low-cost monitoring

    OpenAIRE

    Montserrat Royuela, Albert

    2015-01-01

    In combined sewer systems (CSS) wastewater and stormwater flow through the same pipes. During severe rain episodes, the excess combined flow of untreated wastewater and stormwater is released out from the system through overflow structures, producing the combined sewer overflows (CSO). CSOs represent a threat for water quality of receiving water bodies and for human health, for what current (and future) legislation on the protection of water quality, are demanding more control on this transie...

  16. Changes in water quality parameters due to in-sewer processes.

    Science.gov (United States)

    Boxall, J; Shepherd, W; Guymer, I; Fox, K

    2003-01-01

    Combined sewer systems contain a large number of organic and inorganic pollutants from both domestic and industrial sources. These pollutants are often retained within the combined sewer system for significant lengths of time before entering sewage treatment works, or being spilt to a watercourse via a combined sewer overflow (CSO) during storm conditions. Currently little knowledge exists concerning the effects of in sewer processes on pollutants. Understanding of in-sewer processes is important for the effective and efficient design of treatment works and CSO chambers and for impact assessments on receiving waters. A series of studies covering storm and dry weather flow conditions were undertaken with the aim of investigating the nature of in-sewer processes. These studies consisted of marking a body of water with a fluorescent tracer. The tracer was then monitored at a series of downstream sites, and discrete samples collected from the body of water as it progressed through the sewer. The samples were analysed for water quality parameters and these results investigated in tandem with the detailed hydraulic information gained through the tracer studies. The results highlight the hydraulic differences between storm and dry weather conditions such as increased travel times and mixing under storm conditions. The Advection Dispersion Equation (ADE) and Aggregated Dead Zone (ADZ) model parameters have been quantified for the tracer data. The ADE mixing coefficient is shown to increase by an order of magnitude for storm conditions. The ADZ dispersive fraction parameter is shown to be approximately constant with flow. Chemical reactions and decay within the sewer system were found to be consistent with oxygen limitation.

  17. Preperation for a Clean Surface

    Directory of Open Access Journals (Sweden)

    Aurimas Ralys

    2012-12-01

    Full Text Available The article reviews techniques for preparing clean surfaces used in the manufacturing process, considers the types of clean surfaces and their role in modern production and provides the classification methods of arranging such surfaces. The paper also discusses the principles of methods for solvent cleaning, aqueous cleaning, ultrasonic cleaning, precision cleaning and mechanical cleaning. The study focuses on the possibility of adjusting a clean surface using a water flow, including cavitation.Article in Lithuanian

  18. Preperation for a Clean Surface

    Directory of Open Access Journals (Sweden)

    Aurimas Ralys

    2013-02-01

    Full Text Available The article reviews techniques for preparing clean surfaces used in the manufacturing process, considers the types of clean surfaces and their role in modern production and provides the classification methods of arranging such surfaces. The paper also discusses the principles of methods for solvent cleaning, aqueous cleaning, ultrasonic cleaning, precision cleaning and mechanical cleaning. The study focuses on the possibility of adjusting a clean surface using a water flow, including cavitation.Article in Lithuanian

  19. Design of self-cleansing sanitary sewer systems with the use of flushing devices.

    Science.gov (United States)

    Goormans, T; Engelen, D; Bouteligier, R; Willems, P; Berlamont, J

    2009-01-01

    Many European countries tend to shift from constructing combined sewer systems to separate ones, in order to optimise wastewater treatment efficiency and reduce CSO impact on surface waters. An economic design minimises maintenance requirements by aiming at self-cleansing pipes. However, providing the necessary slopes for self-cleansing sanitary sewer pipes often is unfeasible in flat regions, resulting in an increased risk of loss of hydraulic capacity or blocking. To reduce these risks, flushing tanks can be installed in the sewer system. Where most other researchers contribute to a better understanding of the hydraulics of flushing, this paper rather tries to formulate a methodology to design and test flushing devices in sanitary sewer systems using standards and hydrodynamic simulations. Therefore, several aspects that require consideration when incorporating flushing devices into a sanitary sewer system are discussed. For instance, when flushing sanitary sewers the increase in discharge has to be explicitly considered. A Belgian case study is used to investigate the suitability of the developed methodology. Although the pipe slopes in the methodology are derived assuming uniform flow, the simulation results comply with it. Furthermore, pressurisation of the conduits due to multiple flushing waves remains within acceptable limits.

  20. Sedimentology, stratigraphy and chronology of a decantation tank in the sewer network of Orléans (France).

    Science.gov (United States)

    Jacob, Jérémy; Thibault, Alexandre; Simonneau, Anaëlle; Le Milbeau, Claude; DiGiovanni, Christian; Sabatier, Pierre; Reyss, Jean-Louis; Ardito, Luigi; Morio, Cédric

    2017-04-01

    Current debates on the status of the Anthropocene convey geologists and palaeoenvironmentalists toward new spatial and temporal targets. One of the most emblematic socio-ecosystem of the Anthropocene is urban areas in which the dynamics of materials are mainly controlled by human activities. This brings unprecedented elemental, molecular and isotopic concentrations and distributions that lead Norra (2009) to propose a new geological sphere: the Astysphere. Here we propose that sediments accumulated in sewer networks can provide original, integrated, and multi-thematic archives for the recent history of cities by considering urban systems as any catchment where materials are produced, transported and sedimented. The study site is a decantation tank that collects stormwater and wastewater from the north of Orléans city, upstream wastewater plants in Orléans. Sediments accumulated since 1942 over 17 m depth and were never cleaned out until 2015. Two sedimentary cores of 70 (A) and 250 cm long (B) were collected before clean out and then a third of 150 cm (C) after. Sediments are organized into layers constituted by sands and gravels alternating with silts and organic layers. Sharp contacts between those layers indicate evenemential sedimentation, as expected in sewer networks. We formulate the hypothesis that organic/mineral alternations result from a seasonal dynamic. 7Be presence in topmost sample from core A confirms it was deposited within the last 6 months. In core C, only the upper half core, mostly mineral, displays significant 7Be levels whereas 7Be is absent from the lower half, which is mostly organic. This would confirm that our hypothesis of a seasonal alternation, with organic facies deposited during spring- summer and mineral facies deposited during fall-winter. 30 14C dates measured on cores A and B by postbomb method are logically distributed with depth, the most ancient (beginning of the eighties) being recorder at 2.5m depth. This study shows that

  1. Content-Related Repairing of Inconsistencies in Distributed Data

    Institute of Scientific and Technical Information of China (English)

    Yue-Feng Du; De-Rong Shen; Tie-Zheng Nie; Yue Kou; Ge Yu

    2016-01-01

    Conditional functional dependencies (CFDs) are a critical technique for detecting inconsistencies while they may ignore some potential inconsistencies without considering the content relationship of data. Content-related conditional functional dependencies (CCFDs) are a type of special CFDs, which combine content-related CFDs and detect potential inconsistencies by putting content-related data together. In the process of cleaning inconsistencies, detection and repairing are interactive: 1) detection catches inconsistencies, 2) repairing corrects caught inconsistencies while may bring new incon-sistencies. Besides, data are often fragmented and distributed into multiple sites. It consequently costs expensive shipment for inconsistencies cleaning. In this paper, our aim is to repair inconsistencies in distributed content-related data. We propose a framework consisting of an inconsistencies detection method and an inconsistencies repairing method, which work iteratively. The detection method marks the violated CCFDs for computing the inconsistencies which should be repaired preferentially. Based on the repairing-cost model presented in this paper, we prove that the minimum-cost repairing using CCFDs is NP-complete. Therefore, the repairing method heuristically repairs the inconsistencies with minimum cost. To improve the efficiency and accuracy of repairing, we propose distinct values and rules sequences. Distinct values make less data shipments than real data for communication. Rules sequences determine appropriate repairing sequences to avoid some incorrect repairs. Our solution is proved to be more effective than CFDs by empirical evaluation on two real-life datasets.

  2. Application of the Wallingford Procedure to sewer network rehabilitation; Rehabilitacion de redes de alcantarillado. Aplicando el sistema de Wallingford

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, M. [Universidad Politecnica de de Cataluna. Barcelona (Spain); Lopez, R. [Universitat de Lleida. Lleida (Spain)

    1999-11-01

    In this paper we present a summary of the Wallingford Procedure application to sewer network rehabilitation studies. After the methodology of the Procedure is revised, an application to a sewer network of Sant Boi de Llobregat is showed. Flow survey campaigns, calibration and validation processes and the alternative proposed to improve the initial situation are described. Finally, the benefits to apply such methodologies to the sewer network rehabilitation analysis are exposed. (Author) 3 refs.

  3. Application of the Wallingford Procedure to sewer network rehabilitation. Rehabilitacion de redes de alcantarillado. Aplicando el sistema de Wallingford

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, M. (Universidad Politecnica de de Cataluna. Barcelona (Spain)); Lopez, R. (Universitat de Lleida. Lleida (Spain))

    1999-01-01

    In this paper we present a summary of the Wallingford Procedure application to sewer network rehabilitation studies. After the methodology of the Procedure is revised, an application to a sewer network of Sant Boi de Llobregat is showed. Flow survey campaigns, calibration and validation processes and the alternative proposed to improve the initial situation are described. Finally, the benefits to apply such methodologies to the sewer network rehabilitation analysis are exposed. (Author) 3 refs.

  4. Cleaning and surface properties

    CERN Document Server

    Taborelli, M

    2007-01-01

    Principles of precision cleaning for ultra high vacuum applications are reviewed together with the techniques for the evaluation of surface cleanliness. Methods to verify the effectiveness of cleaning procedures are discussed. Examples are presented to illustrate the influence of packaging and storage on the recontamination of the surface after cleaning. Finally, the effect of contamination on some relevant surface properties, like secondary electron emission and wettability is presented.

  5. Clean Energy Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    For the past several years, the IEA and others have been calling for a clean energy revolution to achieve global energy security, economic growth and climate change goals. This report analyses for the first time progress in global clean energy technology deployment against the pathways that are needed to achieve these goals. It provides an overview of technology deployment status, key policy developments and public spending on RDD&D of clean energy technologies.

  6. [Transport and sources of runoff pollution from urban area with combined sewer system].

    Science.gov (United States)

    Li, Li-Qing; Yin, Cheng-Qing

    2009-02-15

    Sampling and monitoring of runoff and sewage water in Wuhan urban area with combined sewer system were carried out during the period from 2003 to 2006, to study the transport and sources of runoff pollution at the catchment scale coupled with environmental geochemistry method. The results showed a change in quality between the runoff entering the sewer network and the combined storm water flow at the sewer's outlet. A significant increase was observed in the concentrations of total suspended solids (TSS), volatile suspended solids (VSS), COD, TN, and TP, and in the proportion of COD linked to particles. During the runoff production and transport, the concentrations of TSS and COD increased from 18.7 mg/L and 37.0 mg/L in roof runoff, to 225.3 mg/L and 176.5 mg/L in street runoff, and to 449.7 mg/L and 359.9 mg/L in combined storm water flow, respectively. The proportion of COD linked to particles was increased by 18%. In addition, the total phosphorus (P) and iron (Fe) contents in urban ground dust, storm drain sediment, sewage sewer sediment and combined sewer sediment were measured to identify the potential sources of suspended solids in the combined flow. The urban ground dust andstorm drain sediment wererich in Fe, whereas the sewage sewer sediment was rich in P. The P/Fe ratios in these groups were significantly distinct and able to differentiate them. A calculation of the two storm events based on the P/Fe rations showed that 56% +/- 26% of suspended solids in combined flow came from urban ground and storm drain. The rest wer e originated from the sewage sewer sediments which deposited in combined sewer on the dry weather days and were eroded on the wet weather days. The combined sewer network not only acts as a transport system, but also constitutes a physicochemical reactor that degrades the quality of urban water. Reducing the in-sewer pollution stocks would effectively control urban runoff pollution.

  7. Femoral hernia repair

    Science.gov (United States)

    Femorocele repair; Herniorrhaphy; Hernioplasty - femoral ... During surgery to repair the hernia, the bulging tissue is pushed back in. The weakened area is sewn closed or strengthened. This repair ...

  8. Undescended testicle repair

    Science.gov (United States)

    Orchidopexy; Inguinal orchidopexy; Orchiopexy; Repair of undescended testicle; Cryptorchidism repair ... first year of life without treatment. Undescended testicle repair surgery is recommended for patients whose testicles do ...

  9. Multi-objective evolutionary optimization for greywater reuse in municipal sewer systems.

    Science.gov (United States)

    Penn, Roni; Friedler, Eran; Ostfeld, Avi

    2013-10-01

    Sustainable design and implementation of greywater reuse (GWR) has to achieve an optimum compromise between costs and potable water demand reduction. Studies show that GWR is an efficient tool for reducing potable water demand. This study presents a multi-objective optimization model for estimating the optimal distribution of different types of GWR homes in an existing municipal sewer system. Six types of GWR homes were examined. The model constrains the momentary wastewater (WW) velocity in the sewer pipes (which is responsible for solids movement). The objective functions in the optimization model are the total WW flow at the outlet of the neighborhoods sewer system and the cost of the on-site GWR treatment system. The optimization routing was achieved by an evolutionary multi-objective optimization coupled with hydrodynamic simulations of a representative sewer system of a neighborhood located at the coast of Israel. The two non-dominated best solutions selected were the ones having either the smallest WW flow discharged at the outlet of the neighborhood sewer system or the lowest daily cost. In both solutions most of the GWR types chosen were the types resulting with the smallest water usage. This lead to only a small difference between the two best solutions, regarding the diurnal patterns of the WW flows at the outlet of the neighborhood sewer system. However, in the upstream link a substantial difference was depicted between the diurnal patterns. This difference occurred since to the upstream links only few homes, implementing the same type of GWR, discharge their WW, and in each solution a different type of GWR was implemented in these upstream homes. To the best of our knowledge this is the first multi-objective optimization model aimed at quantitatively trading off the cost of local/onsite GW spatially distributed reuse treatments, and the total amount of WW flow discharged into the municipal sewer system under unsteady flow conditions.

  10. Assessment of pollutants and gaseous emissions in sewer network in NCT of Delhi.

    Science.gov (United States)

    Aswale, P; Rao, N N; Karthik, M; Dhodapkar, R; Patkar, G; Nandy, T

    2012-04-01

    The NCT of Delhi in India handles domestic sewage through a long sewerage networks. The network is into eight divisions. The aim of the present study is to arrive at a correlation between sewage quality and gas emissions in the sewer network of various divisions. This will aid in forewarning the sewer workers about the safety precautions. The health effects due to toxic sewer gases exposure and assessment of hazardous conditions and hazard potential are discussed. The study areas were broadly classified as residential, commercial, industrial and mix (combination of residential & commercial) for comparison. Sewage samples were collected from 1020 sites and analyzed for 10 different physicochemical parameters. The analytical data revealed wide variation in the chemical composition of sewage flowing at various sewerage network sites. Based on comparison with the regulatory standard for discharge in sewers, 89 sites with higher values of BOD and sulphate were marked as critical sites. Subsequently, the concentrations of CH4 and H2S in sewer emissions were determined for the 89 critical sites through onsite monitoring. Samples from 22 sites had significantly higher concentration of CH4 than the LEL and those from 40 sites showed concentrations higher than the LFL. On the other hand, samples from 38 locations showed significantly high H2S concentration, more than permissible limit of 10 ppm. The sewer workers in North East, North West and West region of the metropolis were exposed to hazards from excessive CH4 and H2S emissions, whereas those under South and South West regions were more vulnerable to H2S related risks. The sewer network under North, Central and South poses relatively less hazard with regard to gaseous emissions.

  11. Aerobic Heterotrophic Biodégradation in Polluted Drains and Sewers: The drain and sewer as dual-phase biological reactors

    NARCIS (Netherlands)

    Cao, Y.S.

    1994-01-01

    Wastewater collection systems such as sewers, sewage drains, and polluted shallow aquatic systems such as rivers, streams, and lagoons are characterized by the fact that both suspended and attached biomass exist and function. They are dual-phase systems. Contrary to biofilm dominated systems such as

  12. Treatment of combined sewer overflows using ferrate (VI).

    Science.gov (United States)

    Gandhi, Rohan; Ray, Ajay K; Sharma, Virender K; Nakhla, George

    2014-11-01

    This paper presents the results of a study conducted on the treatment of combined sewer overflows using ferrate (VI) [Fe (VI)]. At a Fe (VI) dose of 0.24 mg/L, total chemical oxygen demand (TCOD), soluble chemical oxygen demand (SCOD), total biochemical oxygen demand (TBOD5), soluble biochemical oxygen demand (SBOD5), total suspended solids (TSS), volatile suspended solids (VSS), total phosphorus (TP), total nitrogen (TN), and soluble TN removal efficiencies of 71, 75, 69, 68, 72, 83, 64, 38, and 36%, respectively, were achieved. Kinetic studies revealed that a contact time of only 15 minutes is sufficient to achieve secondary effluent criteria. An innovative technique of using primary sludge (PS) and thickened waste activated sludge as a source for the in situ synthesis of ferrate was developed. A comparative study of treatment efficiencies achieved by Fe (VI) generated from different sources was done. At 0.1 mg/L dose of Fe (VI) synthesized from PS, TCOD, SCOD, TSS, VSS, TP, and TN removal efficiencies of 60, 62, 63, 67, 30, and 25%, respectively, were achieved.

  13. Chemical pretreatment of combined sewer overflows for improved UV disinfection.

    Science.gov (United States)

    Gibson, J; Farnood, R; Seto, P

    2016-01-01

    The aim of this research was to better understand chemical pre-treatment of combined sewer overflows (CSOs) for subsequent ultraviolet (UV) disinfection. Approximately 200 jar tests were completed. Alum (Al2(S04)3·12H2O) resulted in a higher UV light transmission (UVT), and equivalent total suspended solids (TSS) removal, than ferric chloride (FeCl3). An alum dose of 20 mg/L increased the UVT of the raw CSO from 30 to 60% after settling. The addition of 100 mg/L of alum maximized UVT reaching approximately 85%. Flocculation did not increase UVT. However, it did improve the removal of TSS. Cationic polymers worked quickly compared with metal coagulants, but only reached a UVT of 60%. A high positive charge density on the polymer improved the removal of turbidity when compared with low charge, but did not affect UVT. If the goal is to maximise UVT, a very high alum dose may be preferred. If the goal is to minimize coagulant dose with moderate UV performance, cationic polymer at approximately 3 mg/L is recommended.

  14. Mechanical cleaning of graphene

    NARCIS (Netherlands)

    Goossens, A.M.; Calado, V.E.; Barreiro, A.; Watanabe, K.; Taniguchi, T.; Vandersypen, L.M.K.

    2012-01-01

    Contamination of graphene due to residues from nanofabrication often introduces background doping and reduces electron mobility. For samples of high electronic quality, post-lithography cleaning treatments are therefore needed. We report that mechanical cleaning based on contact mode atomic force mi

  15. Intestinal obstruction repair

    Science.gov (United States)

    Repair of volvulus; Intestinal volvulus - repair; Bowel obstruction - repair ... Intestinal obstruction repair is done while you are under general anesthesia . This means you are asleep and DO NOT feel pain. ...

  16. Aortic aneurysm repair - endovascular

    Science.gov (United States)

    EVAR; Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... Endovascular aortic repair is done because your aneurysm is very large, growing quickly, or is leaking or bleeding. You may have ...

  17. Motorcycle Repair.

    Science.gov (United States)

    Hein, Jim; Bundy, Mike

    This motorcycle repair curriculum guide contains the following ten areas of study: brake systems, clutches, constant mesh transmissions, final drives, suspension, mechanical starting mechanisms, electrical systems, fuel systems, lubrication systems, and overhead camshafts. Each area consists of one or more units of instruction. Each instructional…

  18. Turbine repair process, repaired coating, and repaired turbine component

    Energy Technology Data Exchange (ETDEWEB)

    Das, Rupak; Delvaux, John McConnell; Garcia-Crespo, Andres Jose

    2015-11-03

    A turbine repair process, a repaired coating, and a repaired turbine component are disclosed. The turbine repair process includes providing a turbine component having a higher-pressure region and a lower-pressure region, introducing particles into the higher-pressure region, and at least partially repairing an opening between the higher-pressure region and the lower-pressure region with at least one of the particles to form a repaired turbine component. The repaired coating includes a silicon material, a ceramic matrix composite material, and a repaired region having the silicon material deposited on and surrounded by the ceramic matrix composite material. The repaired turbine component a ceramic matrix composite layer and a repaired region having silicon material deposited on and surrounded by the ceramic matrix composite material.

  19. Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas With and Without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007

    Science.gov (United States)

    Background: Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff discharge into waterbodies potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme pre...

  20. Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas With and Without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007

    Science.gov (United States)

    Background: Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff discharge into waterbodies potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme pre...

  1. 77 FR 37439 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2012-06-21

    ... reline sewer lines, a pilot study of combined sewer overflows, and the development of a revised operation... properly operate and maintain its combined sewer system. Under the terms of the Consent Decree, Perth...

  2. Wastewater compounds in urban shallow groundwater wells correspond to exfiltration probabilities of nearby sewers.

    Science.gov (United States)

    Lee, Do Gyun; Roehrdanz, Patrick R; Feraud, Marina; Ervin, Jared; Anumol, Tarun; Jia, Ai; Park, Minkyu; Tamez, Carlos; Morelius, Erving W; Gardea-Torresdey, Jorge L; Izbicki, John; Means, Jay C; Snyder, Shane A; Holden, Patricia A

    2015-11-15

    Wastewater compounds are frequently detected in urban shallow groundwater. Sources include sewage or reclaimed wastewater, but origins are often unknown. In a prior study, wastewater compounds were quantified in waters sampled from shallow groundwater wells in a small coastal California city. Here, we resampled those wells and expanded sample analyses to include sewage- or reclaimed water-specific indicators, i.e. pharmaceutical and personal care product chemicals or disinfection byproducts. Also, we developed a geographic information system (GIS)-based model of sanitary sewer exfiltration probability--combining a published pipe failure model accounting for sewer pipe size, age, materials of construction, with interpolated depths to groundwater--to determine if sewer system attributes relate to wastewater compounds in urban shallow groundwater. Across the wells, groundwater samples contained varying wastewater compounds, including acesulfame, sucralose, bisphenol A, 4-tert-octylphenol, estrone and perfluorobutanesulfonic acid (PFBS). Fecal indicator bacterial concentrations and toxicological bioactivities were less than known benchmarks. However, the reclaimed water in this study was positive for all bioactivity tested. Excluding one well intruded by seawater, the similarity of groundwater to sewage, based on multiple indicators, increased with increasing sanitary sewer exfiltration probability (modeled from infrastructure within ca. 300 m of each well). In the absence of direct exfiltration or defect measurements, sewer exfiltration probabilities modeled from the collection system's physical data can indicate potential locations where urban shallow groundwater is contaminated by sewage.

  3. Sewer Gas: An Indoor Air Source of PCE to Consider During Vapor Intrusion Investigations.

    Science.gov (United States)

    Pennell, Kelly G; Scammell, Madeleine Kangsen; McClean, Michael D; Ames, Jennifer; Weldon, Brittany; Friguglietti, Leigh; Suuberg, Eric M; Shen, Rui; Indeglia, Paul A; Heiger-Bernays, Wendy J

    2013-01-01

    The United States Environmental Protection Agency (USEPA) is finalizing its vapor intrusion guidelines. One of the important issues related to vapor intrusion is background concentrations of volatile organic chemicals (VOCs) in indoor air, typically attributed to consumer products and building materials. Background concentrations can exist even in the absence of vapor intrusion and are an important consideration when conducting site assessments. In addition, the development of accurate conceptual models that depict pathways for vapor entry into buildings is important during vapor intrusion site assessments. Sewer gas, either as a contributor to background concentrations or as part of the site conceptual model, is not routinely evaluated during vapor intrusion site assessments. The research described herein identifies an instance where vapors emanating directly from a sanitary sewer pipe within a residence were determined to be a source of tetrachloroethylene (PCE) detected in indoor air. Concentrations of PCE in the bathroom range from 2.1 to 190 ug/m(3) and exceed typical indoor air concentrations by orders of magnitude resulting in human health risk classified as an "Imminent Hazard" condition. The results suggest that infiltration of sewer gas resulted in PCE concentrations in indoor air that were nearly two-orders of magnitude higher as compared to when infiltration of sewer gas was not known to be occurring. This previously understudied pathway whereby sewers serve as sources of PCE (and potentially other VOC) vapors is highlighted. Implications for vapor intrusion investigations are also discussed.

  4. Influence of pipe material and surfaces on sulfide related odor and corrosion in sewers.

    Science.gov (United States)

    Nielsen, Asbjørn Haaning; Vollertsen, Jes; Jensen, Henriette Stokbro; Wium-Andersen, Tove; Hvitved-Jacobsen, Thorkild

    2008-09-01

    Hydrogen sulfide oxidation on sewer pipe surfaces was investigated in a pilot scale experimental setup. The experiments were aimed at replicating conditions in a gravity sewer located immediately downstream of a force main where sulfide related concrete corrosion and odor is often observed. During the experiments, hydrogen sulfide gas was injected intermittently into the headspace of partially filled concrete and plastic (PVC and HDPE) sewer pipes in concentrations of approximately 1,000 ppm(v). Between each injection, the hydrogen sulfide concentration was monitored while it decreased because of adsorption and subsequent oxidation on the pipe surfaces. The experiments showed that the rate of hydrogen sulfide oxidation was approximately two orders of magnitude faster on the concrete pipe surfaces than on the plastic pipe surfaces. Removal of the layer of reaction (corrosion) products from the concrete pipes was found to reduce the rate of hydrogen sulfide oxidation significantly. However, the rate of sulfide oxidation was restored to its background level within 10-20 days. A similar treatment had no observable effect on hydrogen sulfide removal in the plastic pipe reactors. The experimental results were used to model hydrogen sulfide oxidation under field conditions. This showed that the gas-phase hydrogen sulfide concentration in concrete sewers would typically amount to a few percent of the equilibrium concentration calculated from Henry's law. In the plastic pipe sewers, significantly higher concentrations were predicted because of the slower adsorption and oxidation kinetics on such surfaces.

  5. Sewage flow optimization algorithm for large-scale urban sewer networks based on network community division

    Institute of Scientific and Technical Information of China (English)

    Lihui CEN; Yugeng XI

    2008-01-01

    By considering the flow control of urban sewer networks to minimize the electricity consumption of pumping stations.a decomposition-coordination strategy for energy savings based on network community division is developed in this paper. A mathematical model characterizing the smady-state flow of urball sewer networks is first constructed,consisting of a set of algebraic equations with the structure transportation capacities captured as constraints.Since the sewer networks have no apparent natural hierarchical structure in general.it is very difficult to identify the clustered groups.A fast network division approach through calculating the betweenness of each edge is successfully applied to identify the groups and a sewer network with arbitrary configuration could be then decomposed into subnetworks.By integrating the coupling constraints of the subnetworks.the original problem is separated into N optimization subproblems in accordance with the network decomposition.Each subproblem is solved locally and the solutions to the subproblems are coordinated to form an appropriate global solution.Finally,an application to a specified large-scale sewer network is also investigated to demonstrate the validity of the proposed algorithm.

  6. The distribution dynamics and desorption behaviour of mobile pharmaceuticals and caffeine to combined sewer sediments.

    Science.gov (United States)

    Hajj-Mohamad, M; Darwano, H; Duy, S Vo; Sauvé, S; Prévost, M; Arp, H P H; Dorner, S

    2017-01-01

    Pharmaceuticals are discharged to the environment from wastewater resource recovery facilities, sewer overflows, and illicit sewer connections. To understand the fate of pharmaceuticals, there is a need to better understand their sorption dynamics to suspended sediments (SS) and settled sediments (StS) in sewer systems. In this study, such sorption dynamics to both SS and StS were assessed using a batch equilibrium method under both static and dynamic conditions. Experiments were performed with natively occurring and artificially modified concentrations of sewer pharmaceuticals (acetaminophen, theophylline, carbamazepine, and a metabolite of carbamazepine) and caffeine. Differences in apparent distribution coefficients, Kd,app, between SS and StS were related to differences in their organic carbon (OC) content, and the practice of artificially modifying the concentration. Kd,app values of modified contaminant concentrations and high OC sediments were substantially higher. Pseudo-second order desorption rates for these mobile compounds were also quantified. Successive flushing events to simulate the addition of stormwater to sewer networks revealed that aqueous concentrations would not necessarily decrease, because the added water will rapidly return to equilibrium concentrations with the sediments. Sorption and desorption kinetics must be considered in addition to dilution, to avoid underestimating the influence of dilution on concentrations of pharmaceuticals discharged to the environment.

  7. Hydrocarbons and heavy metals in the different sewer deposits in the ‘Le Marais’ catchment (Paris, France): stocks, distributions and origins

    OpenAIRE

    Rocher, Vincent; Azimi, Sam; Moilleron, Régis; Chebbo, Ghassan

    2004-01-01

    International audience; The knowledge of the pollution stored in combined sewers is of prime importance in terms of management of wet weather flow pollution since sewer deposits play a significant role as source of pollution in combined sewer overflows. This work, which focused on the hydrocarbon (aliphatic and aromatic hydrocarbons) and metallic (Fe, Zn, Pb, Cu and Cd) pollution fixed to the different kinds of sewer deposits (gross bed sediment wGBSx, organic layer wOLx and biofilm), was per...

  8. Heat modeling of wastewater in sewer networks: Determination of thermal energy content from sewage with modeling tools

    NARCIS (Netherlands)

    Elias Maxil, J.A.

    2015-01-01

    This text presents an approach to assess the energy content (flow and temperature) at any point of the sewer system based on the coupling of a stochastic model to predict drinking water demand from households and a model to estimate the temperature distribution in the sewer network. An application e

  9. Relationships between rainfall and Combined Sewer Overflow (CSO) occurrences

    Science.gov (United States)

    Mailhot, A.; Talbot, G.; Lavallée, B.

    2015-04-01

    Combined Sewer Overflow (CSO) has been recognized as a major environmental issue in many countries. In Canada, the proposed reinforcement of the CSO frequency regulations will result in new constraints on municipal development. Municipalities will have to demonstrate that new developments do not increase CSO frequency above a reference level based on historical CSO records. Governmental agencies will also have to define a framework to assess the impact of new developments on CSO frequency and the efficiency of the various proposed measures to maintain CSO frequency at its historic level. In such a context, it is important to correctly assess the average number of days with CSO and to define relationships between CSO frequency and rainfall characteristics. This paper investigates such relationships using available CSO and rainfall datasets for Quebec. CSO records for 4285 overflow structures (OS) were analyzed. A simple model based on rainfall thresholds was developed to forecast the occurrence of CSO on a given day based on daily rainfall values. The estimated probability of days with CSO have been used to estimate the rainfall threshold value at each OS by imposing that the probability of exceeding this rainfall value for a given day be equal to the estimated probability of days with CSO. The forecast skill of this model was assessed for 3437 OS using contingency tables. The statistical significance of the forecast skill could be assessed for 64.2% of these OS. The threshold model has demonstrated significant forecast skill for 91.3% of these OS confirming that for most OS a simple threshold model can be used to assess the occurrence of CSO.

  10. Design and Development of Vision Based Blockage Clearance Robot for Sewer Pipes

    Directory of Open Access Journals (Sweden)

    Krishna Prasad Nesaian

    2012-03-01

    Full Text Available Robotic technology is one of the advanced technologies, which is capable of completing tasks at situations where humans are unable to reach, see or survive. The underground sewer pipelines are the major tools for the transportation of effluent water. A lot of troubles caused by blockage in sewer pipe will lead to overflow of effluent water, sanitation problems. So robotic vehicle that is capable of traveling at underneath effluent water determining blockage using ultrasonic sensors and clearing by means of drilling mechanism is done. In addition to that wireless camera is fixed which acts as a robot vision by which we can monitor video and capture images using MATLAB tool. Thus in this project a prototype model of underground sewer pipe blockage clearance robot with drilling type will be developed

  11. Application of Morphological Segmentation to Leaking Defect Detection in Sewer Pipelines

    Directory of Open Access Journals (Sweden)

    Tung-Ching Su

    2014-05-01

    Full Text Available As one of major underground pipelines, sewerage is an important infrastructure in any modern city. The most common problem occurring in sewerage is leaking, whose position and failure level is typically identified through closed circuit television (CCTV inspection in order to facilitate rehabilitation process. This paper proposes a novel method of computer vision, morphological segmentation based on edge detection (MSED, to assist inspectors in detecting pipeline defects in CCTV inspection images. In addition to MSED, other mathematical morphology-based image segmentation methods, including opening top-hat operation (OTHO and closing bottom-hat operation (CBHO, were also applied to the defect detection in vitrified clay sewer pipelines. The CCTV inspection images of the sewer system in the 9th district, Taichung City, Taiwan were selected as the experimental materials. The segmentation results demonstrate that MSED and OTHO are useful for the detection of cracks and open joints, respectively, which are the typical leakage defects found in sewer pipelines.

  12. Uncertainties Related to Extreme Event Statistics of Sewer System Surcharge and Overflow

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Johansen, C.; Thorndahl, Søren Liedtke

    2005-01-01

    by performing long term simulations - using a sewer flow simulation model - and draw up extreme event statistics from the model simulations. In this context it is important to realize that uncertainties related to the input parameters of rainfall runoff models will give rise to uncertainties related...... to draw up extreme event statistics covering return periods of as much as 33 years. By comparing these two different extreme event statistics it is evident that these to a great extent depend on the uncertainties related to the input parameters of the rainfall runoff model....... proceeding in an acceptable manner, if flooding of these levels is having an average return period bigger than a predefined value. This practice is also often used in functional analysis of existing sewer systems. If a sewer system can fulfil recommended flooding frequencies or not, can only be verified...

  13. Controlling sewer systems – a critical review based on systems in three EU cities

    DEFF Research Database (Denmark)

    Mollerup, Ane Loft; Mikkelsen, Peter Steen; Thornberg, D.

    2017-01-01

    . With the basis of existing frameworks for control system design, a new time-scale dependent framework is proposed. We believe this comprehensive time-scale dependent framework can help water utilities to retrofit and design new control solutions and facilitate knowledge sharing about existing designs.......The term Real Time Control (RTC) is widely used to describe all types of control systems in sewer systems. Today the term covers everything from the simplest to the most advanced types of control systems, making it difficult to communicate about sewer system control in a precise manner, as well...... as search and find specific types of control systems for comparison. Through a survey of implemented control systems in three EU cities today and with the perspectives of current research within the field of sewer system control, the needs for a new control system design framework is identified...

  14. A methodological approach to the design of optimising control strategies for sewer systems

    DEFF Research Database (Denmark)

    Mollerup, Ane Loft; Mikkelsen, Peter Steen; Sin, Gürkan

    2016-01-01

    This study focuses on designing an optimisation based control for sewer system in a methodological way and linking itto a regulatory control. Optimisation based design is found to depend on proper choice of a model, formulation of objective function and tuning of optimisation parameters. Accordin......This study focuses on designing an optimisation based control for sewer system in a methodological way and linking itto a regulatory control. Optimisation based design is found to depend on proper choice of a model, formulation of objective function and tuning of optimisation parameters...... control; a rule based expert system. On the other hand, compared with a regulatory control technique designed earlier in Mollerup et al. (2015), the optimisation showed similar performance with respect to minimising overflow volume. Hence for operation of small sewer systems, regulatory control strategies...... can offer promising potential and should be considered along more advanced strategies when identifying novel solutions....

  15. The role of iron in sulfide induced corrosion of sewer concrete.

    Science.gov (United States)

    Jiang, Guangming; Wightman, Elaine; Donose, Bogdan C; Yuan, Zhiguo; Bond, Philip L; Keller, Jurg

    2014-02-01

    The sulfide-induced corrosion of concrete sewer is a widespread and expensive problem for water utilities worldwide. Fundamental knowledge of the initiation and propagation of sewer corrosion, especially the interactions between chemical reactions and physical structure changes, is still largely unknown. Advanced mineral analytical techniques were applied to identify the distribution of corrosion products and the micro-cracking that developed along the corrosion boundary. It was found that sewer concrete corrosion caused by reactions with sulfuric acid progressed uniformly in the cement of concrete. In contrast to conventional knowledge, iron rust rather than gypsum and ettringite was likely the factor responsible for cracking ahead of the corrosion front. The analysis also allowed quantitative determination of the major corrosion products, i.e., gypsum and ettringite, with the latter found closer to the corrosion front. The conceptual model based on these findings clearly demonstrated the complex interactions among different chemical reactions, diffusion, and micro-structure changes.

  16. Coordinated management of combined sewer overflows by means of environmental decision support systems.

    Science.gov (United States)

    Murla, Damian; Gutierrez, Oriol; Martinez, Montse; Suñer, David; Malgrat, Pere; Poch, Manel

    2016-04-15

    During heavy rainfall, the capacity of sewer systems and wastewater treatment plants may be surcharged producing uncontrolled wastewater discharges and a depletion of the environmental quality. Therefore there is a need of advanced management tools to tackle with these complex problems. In this paper an environmental decision support system (EDSS), based on the integration of mathematical modeling and knowledge-based systems, has been developed for the coordinated management of urban wastewater systems (UWS) to control and minimize uncontrolled wastewater spills. Effectiveness of the EDSS has been tested in a specially designed virtual UWS, including two sewers systems, two WWTP and one river subjected to typical Mediterranean rain conditions. Results show that sewer systems, retention tanks and wastewater treatment plants improve their performance under wet weather conditions and that EDSS can be very effective tools to improve the management and prevent the system from possible uncontrolled wastewater discharges.

  17. Global sensitivity analysis of an in-sewer process model for the study of sulfide-induced corrosion of concrete.

    Science.gov (United States)

    Donckels, B M R; Kroll, S; Van Dorpe, M; Weemaes, M

    2014-01-01

    The presence of high concentrations of hydrogen sulfide in the sewer system can result in corrosion of the concrete sewer pipes. The formation and fate of hydrogen sulfide in the sewer system is governed by a complex system of biological, chemical and physical processes. Therefore, mechanistic models have been developed to describe the underlying processes. In this work, global sensitivity analysis was applied to an in-sewer process model (aqua3S) to determine the most important model input factors with regard to sulfide formation in rising mains and the concrete corrosion rate downstream of a rising main. The results of the sensitivity analysis revealed the most influential model parameters, but also the importance of the characteristics of the organic matter, the alkalinity of the concrete and the movement of the sewer gas phase.

  18. Fat, oil and grease deposits in sewers: characterisation of deposits and formation mechanisms.

    Science.gov (United States)

    Williams, J B; Clarkson, C; Mant, C; Drinkwater, A; May, E

    2012-12-01

    Fat, oil and grease deposits (FOG) in sewers are a major problem and can cause sewer overflows, resulting in environmental damage and health risks. Often simplistically portrayed as cooling of fats, recent research has suggested that saponification may be involved in FOG formation. However there are still questions about the mechanisms effecting transformations in sewers and the role and source of metal cations involved in saponification. This study characterises FOG deposits from pumping stations, sewers and sewage works from different water hardness zones across the UK. The sites all had previous problems with FOG and most catchments contained catering and food preparation establishments. The FOG deposits were highly variable with moisture content ranging from 15 to 95% and oil content from 0 to 548 mg/g. Generally the pumping stations had lower moisture content and higher fat content, followed by the sewers then the sewage works. The water in contact with the FOG had high levels of oil (mean of about 800 mg/L) and this may indicate poor kitchen FOG management practices. FOG fatty acid profiles showed a transformation from unsaturated to saturated forms compared to typical cooking oils. This seems to relate to ageing in the sewer network or the mechanism of formation, as samples from pumping stations had higher proportions of C18:1 compared to C16. This may be due to microbial transformations by bacteria such as Clostridium sp. in a similar process to adipocere formation. There was an association between water hardness and increased Ca levels in FOG along with harder deposits and higher melting points. A link between FOG properties and water hardness has not been previously reported for field samples. This may also be due to microbial processes, such as biocalcification. By developing the understanding of these mechanisms it may be possible to more effectively control FOG deposits, especially when combined with promotion of behavioural change.

  19. Feasibility of sulfide control in sewers by reuse of iron rich drinking water treatment sludge.

    Science.gov (United States)

    Sun, Jing; Pikaar, Ilje; Sharma, Keshab Raj; Keller, Jürg; Yuan, Zhiguo

    2015-03-15

    Dosage of iron salt is the most commonly used method for sulfide control in sewer networks but incurs high chemical costs. In this study, we experimentally investigate the feasibility of using iron rich drinking water treatment sludge for sulfide control in sewers. A lab-scale rising main sewer biofilm reactor was used. The sulfide concentration in the effluent decreased from 15.5 to 19.8 mgS/L (without dosing) to below 0.7-2.3 mgS/L at a sludge dosing rate achieving an iron to total dissolved inorganic sulfur molar ratio (Fe:S) of 1:1, with further removal of sulfide possible by prolonging the reaction time. In fact, batch tests revealed an Fe consumption to sulfide removal ratio of 0.5 ± 0.02 (mole:mole), suggesting the possible occurrence of other reactions involving the removal of sulfide. Modelling revealed that the reaction between iron in sludge and sulfide has reaction orders of 0.65 ± 0.01 and 0.77 ± 0.02 with respect to the Fe and sulfide concentrations, respectively. The addition of sludge slightly increased the total chemical oxidation demand (tCOD) concentration (by approximately 12%) as expected, but decreased the soluble chemical oxidation demand (sCOD) concentration and methane formation by 7% and 20%, respectively. Some phosphate removal (13%) was also observed at the sludge dosing rate of 1:1 (Fe:S), which is beneficial to nutrient removal from the wastewater. Overall, this study suggests that dosing iron-rich drinking water sludge to sewers could be an effective strategy for sulfide removal in sewer systems, which would also reduce the sludge disposal costs for drinking water treatment works. However, its potential side-effects on sewer sedimentation and on the wastewater treatment plant effluent remain to be investigated.

  20. Combined sewer overflows to surface waters detected by the anthropogenic marker caffeine.

    Science.gov (United States)

    Buerge, Ignaz J; Poiger, Thomas; Müller, Markus D; Buser, Hans-Rudolf

    2006-07-01

    Continuous progress in wastewater treatment technology and the growing number of households connected to wastewater treatment plants (WWTPs) have generally resulted in decreased environmental loading of many pollutants. Nonetheless, further reduction of pollutant inputs is required to improve the quality of surface waters in densely populated areas. In this context, the relative contribution of combined sewer overflows as sources of wastewater-derived contaminants has attracted more and more attention, but the quantitative importance of these overflows has barely been investigated. In this study, caffeine was successfully used as a chemical marker to estimate the fraction of sewer overflows in the catchment area of lake Greifensee, Switzerland. Caffeine is a ubiquitous compound in raw, domestic wastewater with typical per capita loads of approximately 16 mg person(-1) d(-1). In WWTPs of the Greifensee region, caffeine is largely eliminated (>99%), resulting in much smaller loads of combined sewer overflows were the most likely source of caffeine. Using a mass balance approach, it was possible to determine the fraction of wastewater (in dry weather equivalents) discharged untreated to the receiving streams (up to 10%, annual mean, approximately 2-3%). The concept of caffeine as a marker for combined sewer overflows was then applied to estimate phosphorus inputs to Greifensee with untreated and treated wastewater (approximately 1.5 and 2.0 t P y(-1), respectively), which corresponded well with P inputs determined in a separate study based on hydraulic considerations. For compounds with high elimination in WWTPs such as phosphorus (96-98% in the Greifensee area), inputs from combined sewer overflows are thus of similar magnitude as inputs from treated wastewater. The study demonstrated that caffeine is a suitable marker for untreated wastewater (from combined sewer overflows, direct discharges, etc.), but its sensitivity depends on regional conditions and decreases

  1. Clean Water Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Clean Water Act (CWA) establishes the basic structure for regulating discharges of pollutants into U.S. waters and regulating quality standards for surface...

  2. Effective Cleaning Radius Studies

    Energy Technology Data Exchange (ETDEWEB)

    Churnetski, B.V.

    2001-10-15

    This report discusses results of testing done in the Savannah River Laboratory half tank and full tank mockup facilities using kaolin clay slurries and the relationship between cleaning radius and pump and slurry characteristics.

  3. Clean Energy Finance Tool

    Science.gov (United States)

    This tool is for state and local governments interested in developing a financing program to support energy efficiency and clean energy improvements for large numbers of buildings within their jurisdiction.

  4. Clean Power Plan Toolbox

    Science.gov (United States)

    These are resources to help states as they develop state implementation plans under section 111(d) of the Clean Air Act to meet EPA's carbon pollution standards for existing power plants. Supplements www2.epa.gov/carbon-pollution-standards.

  5. Kinetics of aerobic oxidation of volatile sulfur compounds in wastewater and biofilm from sewers

    DEFF Research Database (Denmark)

    Rudelle, Elise Alice; Vollertsen, Jes; Hvitved-Jacobsen, Thorkild

    2013-01-01

    -spot downstream of a force main and the other was a gravity sewer transporting young aerobic wastewater. The kinetics of VSC oxidation for both wastewater and suspended biofilm samples followed a first-order rate equation. The average values of the reaction rate constants demonstrated the following order......) and total inorganic sulfide, which have all been reported as the main constituents of foul sewer gas. Samples of wastewater and biofilm for the experiments were obtained from two locations that differed significantly with respect to the occurrence of VSCs. One location represented an odor hot...

  6. Post-rehabilitation evaluation of the sanitary sewer system at Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Royal, D.

    1995-11-01

    We are updating a CH2M Hill study which found that the sanitary sewer system is sufficient to transport peak dry weather flow. However, under peak wet weather conditions, the system has insufficient capacity to transport the projected flows for existing and future development. This is due to the amount of infiltration/inflow (I/I) that enters the sewer system when it rains. Our goal is to examine the existing system to determine its adequacy to accommodate present and future peak flows, and also to further update and improve the CH2M Hill study. A set of alternatives was also developed to address deficiencies of the existing system.

  7. Combined Sewer Overflow pretreatment with chemical coagulation and a particle settler for improved peracetic acid disinfection

    DEFF Research Database (Denmark)

    Chhetri, Ravi Kumar; Bonnerup, Arne; Andersen, Henrik Rasmus

    2016-01-01

    Full scale disinfection by peracetic acid (PAA) was achieved on Combined Sewer Overflow (CSO) water, which was pre-treated physically by a fast settling-filtration unit. Disinfection of untreated CSO water using PAA was compared to treatment using a particle separator (HydroSeparator®) and additi......Full scale disinfection by peracetic acid (PAA) was achieved on Combined Sewer Overflow (CSO) water, which was pre-treated physically by a fast settling-filtration unit. Disinfection of untreated CSO water using PAA was compared to treatment using a particle separator (Hydro...

  8. New Approach for Receiving Water Objectives for Overflows from Sewer Systems

    DEFF Research Database (Denmark)

    Larsen, Torben

    2000-01-01

    The paper describes the results of the work for the establishment of consistent objectives for storm overflows from sewer systems in respect to the physical conditions in streams and rivers in Denmark. First the result of a questionnaire is mentioned. Next some principles of the methods for formu......The paper describes the results of the work for the establishment of consistent objectives for storm overflows from sewer systems in respect to the physical conditions in streams and rivers in Denmark. First the result of a questionnaire is mentioned. Next some principles of the methods...

  9. New approach for receiving water objectives for overflows from sewer systems

    DEFF Research Database (Denmark)

    Larsen, Torben

    1999-01-01

    The paper describes the results of the work for the establishment of consistent objectives for storm overflows from sewer systems in respect to the physical conditions in streams and rivers in Denmark. First the result of a questionnaire is mentioned. Next some principles of the methods for formu......The paper describes the results of the work for the establishment of consistent objectives for storm overflows from sewer systems in respect to the physical conditions in streams and rivers in Denmark. First the result of a questionnaire is mentioned. Next some principles of the methods...

  10. Shape Measurement of a Sewer Pipe Using a Mobile Robot with Computer Vision

    Directory of Open Access Journals (Sweden)

    Kikuhito Kawasue

    2013-01-01

    Full Text Available A mobile robot equipped with two lasers and a CCD camera for pipe inspection is proposed. Circular laser streaks that appeared on the inner surface of the pipe reveal the shape of the pipe. The 3D shape of a sewer pipe can be reconstructed considering the movement of the mobile robot along the pipe. Since the tilt of the mobile robot with respect to the axis of the pipe appears as the deformation between two circular streaks, the shape of a sewer pipe can be measured accurately, regardless of the tilt of the robot.

  11. Cleaning without chlorinated solvents

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.M.; Simandl, R.F.

    1994-12-31

    Because of health and environmental concerns, many regulations have been passed in recent years regarding the use of chlorinated solvents. The Oak Ridge Y-12 Plant has had an active program to find alternatives for these solvents used in cleaning applications for the past 7 years. During this time frame, the quantity of solvents purchased has been reduced by 92%. The program has been a twofold effort. Vapor degreasers used in batch cleaning-operations have been replaced by ultrasonic cleaning with aqueous detergent, and other organic solvents have been identified for use in hand-wiping or specialty operations. In order to qualify these alternatives for use, experimentation was conducted on cleaning ability as well as effects on subsequent operations such as welding, painting and bonding. Cleaning ability was determined using techniques such as X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) which are capable of examining monolayer levels of contamination on a surface. Solvents have been identified for removal of rust preventative oils, lapping oils, machining coolants, lubricants, greases, and mold releases. Solvents have also been evaluated for cleaning urethane foam spray guns, swelling of urethanes and swelling of epoxies.

  12. Clean Metal Finishing Alternatives

    Science.gov (United States)

    2006-05-01

    metals. Hard coating deposition unproven. 3 N/A Weld coating Electrospark Deposition / Alloying (ESD/ ESA) Microarc welding Localized repair of non...mostly soft metals. Hard coating deposition unproven. 3 N/A Weld coating Electrospark Deposition / Alloying (ESD/ ESA) Microarc welding Localized...microwelding process, electrospark deposition , ESD (or electrospark alloying, ESA), has been validated as a localized repair technology11. It is used by

  13. Clean Elements in Abelian Rings

    Indian Academy of Sciences (India)

    Angelina Y M Chin

    2009-04-01

    Let be a ring with identity. An element in is said to be clean if it is the sum of a unit and an idempotent. is said to be clean if all of its elements are clean. If every idempotent in is central, then is said to be abelian. In this paper we obtain some conditions equivalent to being clean in an abelian ring.

  14. Sulfide-iron interactions in domestic wastewater from a gravity sewer

    NARCIS (Netherlands)

    Nielsen, A.H.; Lens, P.N.L.; Vollertsen, J.; Hvitved-Jacobsen, Th.

    2005-01-01

    Interactions between iron and sulfide in domestic wastewater from a gravity sewer were investigated with particular emphasis on redox cycling of iron and iron sulfide formation. The concentration ranges of iron and total sulfide in the experiments were 0.4-5.4 mg Fe L-1 and 0-5.1 mg S L-1, respectiv

  15. Assessment of the effects of greywater reuse on gross solids movement in sewer systems.

    Science.gov (United States)

    Penn, R; Schütze, M; Friedler, E

    2014-01-01

    Onsite greywater reuse (GWR) and installation of water-efficient toilets (WETs) reduce urban freshwater demand and thus enhance urban water use sustainability. Research on GWR and WETs has generally overlooked their potential effects on municipal sewer systems: GWR and WETs affect the flow regime in sewers, and consequently also influence gross solids transport. To asses these impacts, a gross solids transport model was developed. The model is based on approaches found in the literature. Hydrodynamic calculations of sewage flow were performed using the SIMBA6 simulator and then used for the gross solid movement models. Flow characteristics in the up- and downstream sections of the sewer network differ. Therefore different approaches were used to model solids movement in each of these two parts. Each model determines whether a solid moves as a result of a momentary sewage flow, and if it moves, calculation of its velocity is possible. The paper shows the adoption and implementation of two gross solids transport models using SIMBA6 and depicts the results of the effects of various GWR and WET scenarios on gross solids movement in sewers for a real case study in Israel.

  16. Laboratory and field investigation of chemical disinfection of combined sewer overflow in Copenhagen area

    DEFF Research Database (Denmark)

    Chhetri, Ravi Kumar; Thornberg, Dines; Berner, Jesper;

    We investigated the possibility to apply performic acid (PFA) and peracetic acid (PAA) for disinfection of combined sewer overflow (CSO) in existing CSO management infrastructures. The disinfection power of PFA and PAA to Escherichia coli (E. coli) and enterococcus were studied in batch scale...

  17. Chemical disinfection of combined sewer overflow waters using performic acid or peracetic acids

    DEFF Research Database (Denmark)

    Chhetri, Ravi Kumar; Thornberg, Dines; Berner, Jesper;

    2014-01-01

    We investigated the possibility of applying performic acid (PFA) and peracetic acid (PAA) for disinfection of combined sewer overflow (CSO) in existing CSO management infrastructures. The disinfection power of PFA and PAA towards Escherichia coli (E. coli) and Enterococcus was studied in batch...

  18. Modelling Illicit Drug Fate in Sewers for Wastewater-Based Epidemiology

    DEFF Research Database (Denmark)

    Ramin, Pedram

    prevailing in sewers and were operated over 14 months. Abiotic transformation (e.g., hydrolysis) was also evaluated using mineral water and sorption to suspended solids and biofilms were additionally assessed. Overall, two sets of experiments were performed and used for model calibration and model validation...

  19. Temporal asymmetry in precipitation time series and its influence on flow simulations in combined sewer systems

    Science.gov (United States)

    Müller, Thomas; Schütze, Manfred; Bárdossy, András

    2017-09-01

    A property of natural processes is temporal irreversibility. However, this property cannot be reflected by most statistics used to describe precipitation time series and, consequently, is not considered in most precipitation models. In this paper, a new statistic, the asymmetry measure, is introduced and applied to precipitation enabling to detect and quantify irreversibility. It is used to analyze two different data sets of Singapore and Germany. The data of both locations show a significant asymmetry for high temporal resolutions. The asymmetry is more pronounced for Singapore where the climate is dominated by convective precipitation events. The impact of irreversibility on applications is analyzed on two different hydrological sewer system models. The results show that the effect of the irreversibility can lead to biases in combined sewer overflow statistics. This bias is in the same order as the effect that can be achieved by real time control of sewer systems. Consequently, wrong conclusion can be drawn if synthetic time series are used for sewer systems if asymmetry is present, but not considered in precipitation modeling.

  20. Analyzing hydrocarbons in sewer to help in PAH source apportionment in sewage sludges.

    Science.gov (United States)

    Mansuy-Huault, Laurence; Regier, Annette; Faure, Pierre

    2009-05-01

    A multi-molecular approach for polycyclic aromatic hydrocarbons (PAH) source apportionment in sewage sludge was tested. Three simple catchment areas with corresponding wastewater treatment plants (WWTP) were chosen. Sewage sludges of these WWTPs chronically exceeded the French guide values for PAHs. Aliphatic and aromatic hydrocarbons were quantified in sediments or wastewater suspended particulate matter sampled in different locations of the sewer as well as in sewage sludge. Various molecular indices including PAH ratios were calculated. The results showed that the ratios calculated from sewage sludge analyses provided a rather unspecific hydrocarbon fingerprint where combustion input appear as the main PAH sources. The complexity of the inputs as well as degradation occurring during wastewater treatment prevent any detailed diagnosis. Coupled to the analyses of samples collected in the sewer, the multi-molecular approach becomes more efficient especially for the identification of specific petroleum inputs such as fuel or used lubricating oils which can be important PAH sources. Indeed, the sampling in the sewer allows a spatial screening of the hydrocarbon inputs and facilitates the PAH source apportionment by avoiding the dilution of specific inputs with the whole wastewater inputs and by limiting the degradation of the molecular fingerprint that could occur during transfer and treatment in the WWTP. Then, the combination of PAH ratios and aliphatic distribution analyses is a very valuable approach that can help in sewer and WWTP management.

  1. Control of Sewer systems and Wastewater treatment plants using pollutant concentration profiles

    DEFF Research Database (Denmark)

    Bechmann, Henrik; Nielsen, Marinus K.; Madsen, Henrik

    1998-01-01

    On-line measurements of pollutants in the wastewater combined with grey-box modelling are used to estimate the amount of deposits in the sewer system. The pollutant mass flow at the wastewater treatment plant is found to consist of a diurnal profile minus the deposited amount of pollutants...

  2. High-Rate Disinfection Techniques for Combined Sewer Overflow (Proceedings Paper)

    Science.gov (United States)

    This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH ), a...

  3. Reliability of adaptive multivariate software sensors for sewer water quality monitoring

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen

    2015-01-01

    This study investigates the use of a multivariate approach, based on Principal Component Analysis PCA), as software sensor for fault detection and reconstruction of missing measurements in on-line monitoring of sewer water quality. The analysis was carried out on a 16-months dataset of five...

  4. 76 FR 35215 - Notice of EPA Workshop on Sanitary Sewer Overflows and Peak Wet Weather Discharges

    Science.gov (United States)

    2011-06-16

    ... Pennsylvania Avenue, NW. FOR FURTHER INFORMATION CONTACT: For further information about this notice, contact... or e-mail: schaner.greg@epa.gov . SUPPLEMENTARY INFORMATION: I. Background Properly designed..., line breaks, sewer defects that allow storm water and groundwater to overload the system, lapses in...

  5. Effects of climate and sewer condition on virus transport to groundwater

    Science.gov (United States)

    Pathogen contamination from leaky sanitary sewers poses a threat to groundwater quality in urban areas, yet the spatial and temporal dimensions of this contamination are not well understood. In this study, 16 monitoring wells and six municipal wells were repeatedly sampled for human enteric viruses....

  6. Controlling chemical dosing for sulfide mitigation in sewer networks using a hybrid automata control strategy.

    Science.gov (United States)

    Liu, Yiqi; Ganigué, Ramon; Sharma, Keshab; Yuan, Zhiguo

    2013-01-01

    Chemicals such as magnesium hydroxide (Mg(OH)2) and iron salts are widely used to control sulfide-induced corrosion in sewer networks composed of interconnected sewer pipe lines and pumping stations. Chemical dosing control is usually non-automatic and based on experience, thus often resulting in sewage reaching the discharge point receiving inadequate or even no chemical dosing. Moreover, intermittent operation of pumping stations makes traditional control theory inadequate. A hybrid automata-based (HA-based) control method is proposed in this paper to coordinate sewage pumping station operations by considering their states, thereby ensuring suitable chemical concentrations in the network discharge. The performance of the proposed control method was validated through a simulation study of a real sewer network using real sewage flow data. The physical, chemical and biological processes were simulated using the well-established SeweX model. The results suggested that the HA-based control strategy significantly improved chemical dosing control performance and sulfide mitigation in sewer networks, compared to the current common practice.

  7. Quality of visual sewer inspection data: The need for a new coding system?! (poster)

    NARCIS (Netherlands)

    Dirksen, J.; Van der Steen, A.; Langeveld, J.G.; Clemens, F.H.L.R.

    2013-01-01

    Previous research learned that the reproducibility of visual sewer inspection data is poor (Dirksen et al.). Further research by Arjan et al. showed that the applied coding system has a major influence on the reproducibility. The aim of this study was to give relevant suggestions to improve the qual

  8. Microbiologically Induced Corrosion of Concrete and Protective Coatings in Gravity Sewers

    Institute of Scientific and Technical Information of China (English)

    Marjorie Valix; Diyana Zamri; Hiro Mineyama; Wai Hung Cheung; Jeffrey Shi; Heri Bustamante

    2012-01-01

    Microbiologically induced corrosion of concrete (MICC) and its protective coatings has a high eco-nomic impact on sewer maintenance and rehabilitation. A better understanding of the micro-organisms and the bio- genie acids that are generated in the sewer is essential in controlling the corrosion of concrete pipes and protective coatings. The role of succession of micro-organisms growth in the corrosion of concrete and protective coatings was evaluated in this study. Examination of various sewer pipe materials exhibiting various extents of degradation, including concrete, cement based and epoxy based coating revealed the presence of both organic and biogenic sulphuric acids. This reflects the activity of fungi and the thiobacilli strains. Organism growth and metabolism were strongly related to the substrate pH. Fungi were found to grow and metabolise organic acids at pH from 2.0-8.0. Whilst the thiobacilli strains grew and generated sulohuric acids at oH below 3.0. The successive growth of the organisms provides an impgrtant bearing in deyeloping improved strateegies.to better manage sewers.

  9. Sulfide-iron interactions in domestic wastewater from a gravity sewer

    NARCIS (Netherlands)

    Nielsen, A.H.; Lens, P.N.L.; Vollertsen, J.; Hvitved-Jacobsen, Th.

    2005-01-01

    Interactions between iron and sulfide in domestic wastewater from a gravity sewer were investigated with particular emphasis on redox cycling of iron and iron sulfide formation. The concentration ranges of iron and total sulfide in the experiments were 0.4-5.4 mg Fe L-1 and 0-5.1 mg S L-1, respectiv

  10. Determination of kinetics and stoichiometry of chemical sulfide oxidation in wastewater of sewer networks

    DEFF Research Database (Denmark)

    Nielsen, A.H.; Vollertsen, Jes; Hvitved-jacobsen, Thorkild

    2003-01-01

    A method for determination of kinetics and stoichiometry of chemical sulfide oxidation by dissolved oxygen (DO) in wastewater is presented. The method was particularly developed to investigate chemical sulfide oxidation in wastewater of sewer networks at low DO concentrations. The method is based...

  11. Corrosion of concrete sewers--the kinetics of hydrogen sulfide oxidation.

    Science.gov (United States)

    Vollertsen, Jes; Nielsen, Asbjørn Haaning; Jensen, Henriette Stokbro; Wium-Andersen, Tove; Hvitved-Jacobsen, Thorkild

    2008-05-01

    Hydrogen sulfide absorption and oxidation by corroding concrete surfaces was quantified in a test rig consisting of 6 concrete pipes operated under sewer conditions. The test rig was placed in an underground sewer monitoring station with access to fresh wastewater. Hydrogen sulfide gas was injected into the pipe every 2nd hour to peak concentrations around 1000 ppm. After some months of operation, the hydrogen sulfide became rapidly oxidized by the corroding concrete surfaces. At hydrogen sulfide concentrations of 1000 ppm, oxidation rates as high as 1 mg S m(-2) s(-1) were observed. The oxidation process followed simple nth order kinetics with a process order of 0.45-0.75. Extrapolating the results to gravity sewer systems showed that hydrogen sulfide oxidation by corroding concrete is a fast process compared to the release of hydrogen sulfide from the bulk water, resulting in low gas concentrations compared with equilibrium. Balancing hydrogen sulfide release with hydrogen sulfide oxidation at steady state conditions demonstrated that significant corrosion rates--several millimeters of concrete per year--can potentially occur at hydrogen sulfide gas phase concentrations well below 5-10 ppm. The results obtained in the study advances the knowledge on prediction of sewer concrete corrosion and the extent of odor problems.

  12. High-throughput amplicon sequencing reveals distinct communities within a corroding concrete sewer system.

    Science.gov (United States)

    Cayford, Barry I; Dennis, Paul G; Keller, Jurg; Tyson, Gene W; Bond, Philip L

    2012-10-01

    Microbially induced concrete corrosion (MICC) is an important problem in sewers. Here, small-subunit (SSU) rRNA gene amplicon pyrosequencing was used to characterize MICC communities. Microbial community composition differed between wall- and ceiling-associated MICC layers. Acidithiobacillus spp. were present at low abundances, and the communities were dominated by other sulfur-oxidizing-associated lineages.

  13. Predicting the Probability of Failure of Cementitious Sewer Pipes Using Stochastic Finite Element Method

    Directory of Open Access Journals (Sweden)

    Amir M. Alani

    2015-06-01

    Full Text Available In this paper, a stochastic finite element method (SFEM is employed to investigate the probability of failure of cementitious buried sewer pipes subjected to combined effect of corrosion and stresses. A non-linear time-dependant model is used to determine the extent of concrete corrosion. Using the SFEM, the effects of different random variables, including loads, pipe material, and corrosion on the remaining safe life of the cementitious sewer pipes are explored. A numerical example is presented to demonstrate the merit of the proposed SFEM in evaluating the effects of the contributing parameters upon the probability of failure of cementitious sewer pipes. The developed SFEM offers many advantages over traditional probabilistic techniques since it does not use any empirical equations in order to determine failure of pipes. The results of the SFEM can help the concerning industry (e.g., water companies to better plan their resources by providing accurate prediction for the remaining safe life of cementitious sewer pipes.

  14. Mechanisms of fat, oil and grease (FOG) deposit formation in sewer lines.

    Science.gov (United States)

    He, Xia; de los Reyes, Francis L; Leming, Michael L; Dean, Lisa O; Lappi, Simon E; Ducoste, Joel J

    2013-09-01

    FOG deposits in sewer systems have recently been shown to be metallic salts of fatty acids. However, the fate and transport of FOG deposit reactant constituents and the complex interactions during the FOG deposit formation process are still largely unknown. In this study, batch tests were performed to elucidate the mechanisms of FOG deposit formation that lead to sanitary sewer overflows (SSOs). We report the first formation of FOG deposits on a concrete surface under laboratory conditions that mimic the formation of deposits in sewer systems. Results showed that calcium, the dominant metal in FOG deposits, can be released from concrete surfaces under low pH conditions and contribute to the formation process. Small amounts of additional oil to grease interceptor effluent substantially facilitated the air/water or pipe surface/water interfacial reaction between free fatty acids and calcium to produce surface FOG deposits. Tests of different fatty acids revealed that more viscous FOG deposit solids were formed on concrete surfaces, and concrete corrosion was accelerated, in the presence of unsaturated FFAs versus saturated FFAs. Based on all the data, a comprehensive model was proposed for the mechanisms of FOG deposit formation in sewer systems.

  15. Spatial Models of Sewer Pipe Leakage Predict the Occurrence of Wastewater Indicators in Shallow Urban Groundwater.

    Science.gov (United States)

    Roehrdanz, Patrick R; Feraud, Marina; Lee, Do Gyun; Means, Jay C; Snyder, Shane A; Holden, Patricia A

    2017-02-07

    Twentieth century municipal wastewater infrastructure greatly improved U.S. urban public health and water quality. However, sewer pipes deteriorate, and their accumulated structural defects may release untreated wastewater to the environment via acute breaks or insidious exfiltration. Exfiltrated wastewater constitutes a loss of potentially reusable water and delivers a complex and variable mix of contaminants to urban shallow groundwater. Yet, predicting where deteriorated sewers impinge on shallow groundwater has been challenging. Here we develop and test a spatially explicit model of exfiltration probability based on pipe attributes and groundwater elevation without prior knowledge of exfiltrating defect locations. We find that models of exfiltration probability can predict the probable occurrence in underlying shallow groundwater of established wastewater indicators including the artificial sweetener acesulfame, tryptophan-like fluorescent dissolved organic matter, nitrate, and a stable isotope of water (δ(18)O). The strength of the association between exfiltration probability and indicators of wastewater increased when multiple pipe attributes, distance weighting, and groundwater flow direction were considered in the model. The results prove that available sanitary sewer databases and groundwater digital elevation data can be analyzed to predict where pipes are likely leaking and contaminating groundwater. Such understanding could direct sewer infrastructure reinvestment toward water resource protection.

  16. Transformation of AgCl nanoparticles in a sewer system--A field study.

    Science.gov (United States)

    Kaegi, Ralf; Voegelin, Andreas; Sinnet, Brian; Zuleeg, Steffen; Siegrist, Hansruedi; Burkhardt, Michael

    2015-12-01

    Silver nanoparticles (Ag-NP) are increasingly used in consumer products and their release during the use phase may negatively affect aquatic ecosystems. Research efforts, so far, have mainly addressed the application and use of metallic Ag(0)-NP. However, as shown by recent studies on the release of Ag from textiles, other forms of Ag, especially silver chloride (AgCl), are released in much larger quantities than metallic Ag(0). In this field study, we report the release of AgCl-NP from a point source (industrial laundry that applied AgCl-NP during a piloting phase over a period of several months to protect textiles from bacterial regrowth) to the public sewer system and investigate the transformation of Ag during its transport in the sewer system and in the municipal wastewater treatment plant (WWTP). During the study period, the laundry discharged ~85 g of Ag per day, which dominated the Ag loads in the sewer system from the respective catchment (72-95%) and the Ag in the digested WWTP sludge (67%). Combined results from electron microscopy and X-ray absorption spectroscopy revealed that the Ag discharged from the laundry to the sewer consisted of about one third AgCl and two thirds Ag2S, both forms primarily occurring as nanoparticles with diameters95%). Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Biological assessment of effects of combined sewer overflows and storm water discharges.

    NARCIS (Netherlands)

    Lijklema, L.; Roijackers, R.M.M.; Cuppen, J.G.M.

    1989-01-01

    The biological effects of discharges from combined or separated sewer systems are difficult to assess or to predict due to variahilities in concentrations, environmental conditions, morphometry, susceptibility of organisms, seasonality and other factors. A general discussion of the problem results i

  18. Combined sewer overflows in urban areas - interpreting and comparing European CSO monitoring results

    NARCIS (Netherlands)

    Aarts, A.L.F.; Langeveld, J.G.; Ten Veldhuis, J.A.E.; Rietveld, L.C.

    2013-01-01

    Since the initiation of environmental legislation, monitoring campaigns have been done to estimate the characteristic pollutant concentrations of combined sewer overflow water. Such local campaigns are expensive due to the large number of events which should ideally be followed. This study focused o

  19. Assessment of pollutant load emission from combined sewer overflows based on the online monitoring.

    Science.gov (United States)

    Brzezińska, Agnieszka; Zawilski, Marek; Sakson, Grażyna

    2016-09-01

    Cities equipped with combined sewer systems discharge during wet weather a lot of pollutants into receiving waters by combined storm overflows (CSOs). According to the Polish legislation, CSOs should be activated no more than ten times per year, but in Lodz, most of the 18 existing CSOs operate much more frequently. To assess the pollutant load emitted by one of the existing CSOs, the sensors for measuring the concentration of total suspended solids (SOLITAX sc) and dissolved chemical oxygen demand (UVAS plus) installed in the overflow chamber as well as two flowmeters placed in the outflow sewer were used. In order to check the data from sensors, laboratory tests of combined wastewater quality were conducted simultaneously. For the analysis of the total pollutant load emitted from the overflow, the raw data was denoised using the Savitzky-Golay method. Comparing the load calculated from the analytical results to online smoothed measurements, negligible differences were found, which confirms the usefulness of applying the sensors in the combined sewer system. Online monitoring of the quantity and quality of wastewater emitted by the combined sewer overflows to water receivers, provides a considerable amount of data very useful for combined sewerage upgrading based on computer modelling, and allows for a significant reduction of laboratory analysis.

  20. Measuring Flow Reductions in a Combined Sewer System Using Green Infrastructure

    Science.gov (United States)

    A green infrastructure (GI) design approach was used in CSO Basin #130, a 17-acre sewershed in the Butchertown section of Louisville, Kentucky, to reduce combined sewer overflows (CSOs). For the design year, the modeled design was expected to reduce the CSO frequency from 34 to ...

  1. Research of trace metals as markers of entry pathways in combined sewers.

    Science.gov (United States)

    Gounou, C; Varrault, G; Amedzro, K; Gasperi, J; Moilleron, R; Garnaud, S; Chebbo, G

    2011-01-01

    Combined sewers receive high toxic trace metal loads emitted by various sources, such as traffic, industry, urban heating and building materials. During heavy rain events, Combined Sewer Overflows (CSO) can occur and, if so, are discharged directly into the aquatic system and therefore could have an acute impact on receiving waters. In this study, the concentrations of 18 metals have been measured in 89 samples drawn from the three pollutant Entry Pathways in Combined Sewers (EPCS): i) roof runoff, ii) street runoff, and iii) industrial and domestic effluents and also drawn from sewer deposits (SD). The aim of this research is to identify metallic markers for each EPCS; the data matrix was submitted to principal component analysis in order to determine metallic markers for the three EPCS and SD. This study highlights the fact that metallic content variability across samples from different EPCS and SD exceeds the spatio-temporal variability of samples from the same EPCS. In the catchment studied here, the most valuable EPCS and SD markers are lead, sodium, boron, antimony and zinc; these markers could be used in future studies to identify the contributions of each EPCS to CSO metallic loads.

  2. Monitoring the Startup of a Sacrificial Concrete Sewer for Odor Control

    DEFF Research Database (Denmark)

    Nielsen, Asbjørn Haaning; Vollertsen, Jes

    2014-01-01

    to reduce hydrogen sulphide gas (H2S (g)) concentrations in the sewer headspace. After being in operation for approximately half a year, the system was able to maintain average H2S (g) levels of less than 1 ppmv at the downstream end, which is the first place air can escape. The daily maximum H2S (g) levels...

  3. Resistance to anticoagulants in rats (Rattus norvegicus) in sewers in an urban area

    DEFF Research Database (Denmark)

    Lodal, Jens

    2007-01-01

    . Therefore a project for studying resistance levels in sewer rats was undertaken in an urban area of a municipality in southern Zealand from where surface rats had been tested during the foregoing years. Rats resistant to difenacoum represented the highest level of resistance in the municipality. Rats were...

  4. Sewer Lateral Electro Scan Field Verification Pilot (WERF Report INFR4R12)

    Science.gov (United States)

    Abstract:WERF selected a proposed research project to field test an emerging technology for inspecting sanitary sewer lateral pipes. The technology is called Electro Scan and is used to find defects in laterals that allow the infiltration of groundwater into the lateral. Electro ...

  5. Modelling sewer sediment deposition, erosion, and transport processes to predict acute influent and reduce combined sewer overflows and CO(2) emissions.

    Science.gov (United States)

    Mouri, Goro; Oki, Taikan

    2010-01-01

    Understanding of solids deposition, erosion, and transport processes in sewer systems has improved considerably in the past decade. This has provided guidance for controlling sewer solids and associated acute pollutants to protect the environment and improve the operation of wastewater systems. Although measures to decrease combined sewer overflow (CSO) events have reduced the amount of discharged pollution, overflows continue to occur during rainy weather in combined sewer systems. The solution lies in the amount of water allotted to various processes in an effluent treatment system, in impact evaluation of water quality and prediction technology, and in stressing the importance of developing a control technology. Extremely contaminated inflow has been a serious research subject, especially in connection with the influence of rainy weather on nitrogen and organic matter removal efficiency in wastewater treatment plants (WWTP). An intensive investigation of an extremely polluted inflow load to WWTP during rainy weather was conducted in the city of Matsuyama, the region used for the present research on total suspended solid (TSS) concentration. Since the inflow during rainy weather can be as much as 400 times that in dry weather, almost all sewers are unsettled and overflowing when a rain event is more than moderate. Another concern is the energy consumed by wastewater treatment; this problem has become important from the viewpoint of reducing CO(2) emissions and overall costs. Therefore, while establishing a prediction technology for the inflow water quality characteristics of a sewage disposal plant is an important priority, the development of a management/control method for an effluent treatment system that minimises energy consumption and CO(2) emissions due to water disposal is also a pressing research topic with regards to the quality of treated water. The procedure to improve water quality must make use of not only water quality and biotic criteria, but also

  6. Transformation of AgCl nanoparticles in a sewer system — A field study

    Energy Technology Data Exchange (ETDEWEB)

    Kaegi, Ralf, E-mail: ralf.kaegi@eawag.ch [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600 Dübendorf (Switzerland); Voegelin, Andreas; Sinnet, Brian [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600 Dübendorf (Switzerland); Zuleeg, Steffen [KUSTER + HAGER Group, Oberstrasse 222, 9014 St. Gallen (Switzerland); Siegrist, Hansruedi [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600 Dübendorf (Switzerland); Burkhardt, Michael [HSR University of Applied Sciences, Institute of Environmental and Process Engineering (UMTEC), Oberseestrasse 10, 8640 Rapperswil (Switzerland)

    2015-12-01

    Silver nanoparticles (Ag-NP) are increasingly used in consumer products and their release during the use phase may negatively affect aquatic ecosystems. Research efforts, so far, have mainly addressed the application and use of metallic Ag(0)-NP. However, as shown by recent studies on the release of Ag from textiles, other forms of Ag, especially silver chloride (AgCl), are released in much larger quantities than metallic Ag(0). In this field study, we report the release of AgCl-NP from a point source (industrial laundry that applied AgCl-NP during a piloting phase over a period of several months to protect textiles from bacterial regrowth) to the public sewer system and investigate the transformation of Ag during its transport in the sewer system and in the municipal wastewater treatment plant (WWTP). During the study period, the laundry discharged ~ 85 g of Ag per day, which dominated the Ag loads in the sewer system from the respective catchment (72–95%) and the Ag in the digested WWTP sludge (67%). Combined results from electron microscopy and X-ray absorption spectroscopy revealed that the Ag discharged from the laundry to the sewer consisted of about one third AgCl and two thirds Ag{sub 2}S, both forms primarily occurring as nanoparticles with diameters < 100 nm. During the 800 m transport in the sewer channel to the nearby WWTP, corresponding to a travel time of ~ 30 min, the remaining AgCl was transformed into nanoparticulate Ag{sub 2}S. Ag{sub 2}S-NP also dominated the Ag speciation in the digested sludge. In line with results from earlier studies, the very low Ag concentrations measured in the effluent of the WWTP (< 0.5 μg L{sup −1}) confirmed the very high removal efficiency of Ag from the wastewater stream (> 95%). - Highlights: • First field study on the transformation of AgCl nanoparticles released from a point source into the municipal sewer system. • Transformation of AgCl-NP into Ag{sub 2}S already occurred during 30-min transport in the

  7. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  8. Ventral hernia repair

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007661.htm Ventral hernia repair To use the sharing features on this page, please enable JavaScript. Ventral hernia repair is surgery to repair a ventral hernia. ...

  9. Brain aneurysm repair

    Science.gov (United States)

    ... aneurysm repair; Dissecting aneurysm repair; Endovascular aneurysm repair - brain; Subarachnoid hemorrhage - aneurysm ... Your scalp, skull, and the coverings of the brain are opened. A metal clip is placed at ...

  10. Repair of overheating linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Barkley, Walter; Baldwin, William; Bennett, Gloria; Bitteker, Leo; Borden, Michael; Casados, Jeff; Fitzgerald, Daniel; Gorman, Fred; Johnson, Kenneth; Kurennoy, Sergey; Martinez, Alberto; O’Hara, James; Perez, Edward; Roller, Brandon; Rybarcyk, Lawrence; Stark, Peter; Stockton, Jerry

    2004-01-01

    Los Alamos Neutron Science Center (LANSCE) is a proton accelerator that produces high energy particle beams for experiments. These beams include neutrons and protons for diverse uses including radiography, isotope production, small feature study, lattice vibrations and material science. The Drift Tube Linear Accelerator (DTL) is the first portion of a half mile long linear section of accelerator that raises the beam energy from 750 keV to 100 MeV. In its 31st year of operation (2003), the DTL experienced serious issues. The first problem was the inability to maintain resonant frequency at full power. The second problem was increased occurrences of over-temperature failure of cooling hoses. These shortcomings led to an investigation during the 2003 yearly preventative maintenance shutdown that showed evidence of excessive heating: discolored interior tank walls and coper oxide deposition in the cooling circuits. Since overheating was suspected to be caused by compromised heat transfer, improving that was the focus of the repair effort. Investigations revealed copper oxide flow inhibition and iron oxide scale build up. Acid cleaning was implemented with careful attention to protection of the base metal, selection of components to clean and minimization of exposure times. The effort has been very successful in bringing the accelerator through a complete eight month run cycle allowing an incredible array of scientific experiments to be completed this year (2003-2004). This paper will describe the systems, investigation analysis, repair, return to production and conclusion.

  11. Neutrino Detection With CLEAN

    CERN Document Server

    McKinsey, D N

    2005-01-01

    This article describes CLEAN, an approach to the detection of low-energy solar neutrinos and neutrinos released from supernovae. The CLEAN concept is based on the detection of elastic scattering events (neutrino-electron scattering and neutrino-nuclear scattering) in liquified noble gases such as liquid helium, liquid neon, and liquid xenon, all of which scintillate brightly in the ultraviolet. Key to the CLEAN technique is the use of a thin film of wavelength-shifting fluor to convert the ultraviolet scintillation light to the visible. This allows the same liquid to be used as both a passive shielding medium and an active self-shielding detector, allowing lower intrinsic radioactive backgrounds at low energies. Liquid neon is a particularly promising medium for CLEAN. Because liquid neon has a high scintillation yield, has no long-lived radioactive isotopes, and can be easily purified by use of cold traps, it is an ideal medium for the detection of rare nuclear events. In addition, neon is inexpensive, dense...

  12. Clean energy microgrids

    CERN Document Server

    Obara, Shin'ya

    2017-01-01

    This book describes the latest technology in microgrids and economic, environmental and policy aspects of their implementation, including microgrids for cold regions, and future trends. The aim of this work is to give this complete overview of the latest technology around the world, and the interrelation with clean energy systems.

  13. Cleanly: trashducation urban system

    DEFF Research Database (Denmark)

    Reif, Inbal; Alt, Florian; Ramos, Juan David Hincapie

    are exacerbated by a poor personal trash management culture. In this paper we present Cleanly, an urban trashducation system aimed at creating awareness of garbage production and management, which may serve as an educational plat-form in the urban environment. We report on data collected from an online survey...

  14. Clean Cities Tools

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-12-19

    The U.S. Department of Energy's Clean Cities offers a large collection of Web-based tools on the Alternative Fuels Data Center. These calculators, interactive maps, and data searches can assist fleets, fuels providers, and other transportation decision makers in their efforts to reduce petroleum use.

  15. WINDOW-CLEANING

    CERN Multimedia

    Environmental Section / ST-TFM

    2001-01-01

    The two-month window-cleaning session on the Meyrin, Prévessin and LEP sites will soon begin. The cleaning contractors will work from Monday to Saturday, every week from 4.00 a.m. to 8.00 p.m. The work will be organised so as to disturb users as little as possible. In any event, a work notice will be left in each office 24 hours beforehand. To prevent any damage to documents or items which could occur despite the precautions taken, please clear completely the window-sills and the area immediately around them. If, however, for valid reasons, the work cannot be done on the scheduled day, please inform the Environmental Section by telephoning: 73753 / 74233 / 72242 If you are going to be absent during this two-month period, we should be grateful if you would clear the above mentioned areas before your departure. REMINDER To allow more thorough cleaning of the entrance doors to buildings and also facilitate the weekly work of the cleaning contractors, we ask you to make use of the notice boards at the...

  16. WINDOW-CLEANING

    CERN Multimedia

    Environmental Section / ST-TFM

    2001-01-01

    The two-month window-cleaning session on the Meyrin, Prévessin and LEP sites will soon begin. The cleaning contractors will work from Monday to Saturday, every week from 4.00 a.m. to 8.00 p.m. The work will be organised so as to disturb users as little as possible. In any event, a work notice will be left in each office 24 hours beforehand. To prevent any damage to documents or items which could occur despite the precautions taken, please clear completely the window-sills and the area immediately around them. If, however, for valid reasons, the work cannot be done on the scheduled day, please inform the Environmental Section by telephoning: 73753 / 74233 / 72242 If you are going to be absent during this two-month period, we should be grateful if you would clear the above mentioned areas before your departure. REMINDER To allow more thorough cleaning of the entrance doors to buildings and also facilitate the weekly work of the cleaning contractors, we ask you to make use of the notice boards at the...

  17. 78 FR 24778 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2013-04-26

    ... its combined sewer system and its separated sewer system to reduce or eliminate unlawful overflows of... City of Seattle, Washington (``City'') operation of its sewer system in the Seattle area. The proposed... discharge points within the City's sewer system. The City will also pay a total of $350,000.00 in...

  18. 76 FR 49505 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2011-08-10

    ... sewage from its sanitary sewer system-- discharges that often are referred to as Sanitary Sewer Overflows or ``SSOs''--and from MSD's combined storm water and sanitary sewer system--discharges that often are referred to as Combined Sewer Overflows or ``CSOs''--violate MSD's National Pollutant Discharge...

  19. RATES OF GASTROINTESTINAL ILLNESS AMONG AREAS IMPACTED BY COMBINED SEWER FACILITIES: ANALYSIS OF MASSACHUSETTS DATA, 2003-2007

    Science.gov (United States)

    Previous studies have reported a temporal association between heavy rainfall and gastrointestinal infection (GI). Combined sewer systems (CSSs), which are present in many urban areas in the US, were designed to collect rainwater runoff, domestic sewage, and industrial wastewater ...

  20. Scanned Hardcopy Maps, All Engineering hanging files: sewer, water, construction plans, and subdivisions, Published in 2008, City of Hutchinson.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Scanned Hardcopy Maps dataset, was produced all or in part from Hardcopy Maps information as of 2008. It is described as 'All Engineering hanging files: sewer,...

  1. 78 FR 9908 - Notice of Availability of the Draft Issuance of the Small Municipal Separate Storm Sewer System...

    Science.gov (United States)

    2013-02-12

    ... sewer systems in municipalities such as systems at military bases, large hospital or prison complexes... meet the MEP standard. The iterative process of MEP consists of a municipality developing a...

  2. Effects of combined-sewer overflows and urban runoff on the water quality of Fall Creek, Indianapolis, Indiana

    Science.gov (United States)

    Martin, J.D.

    1995-01-01

    In 1986, the U.S. Geological Survey and the Indianapolis Department of Public Works began a study to evaluate the effects of combined-sewer overflows and urban runoff discharging to Fall Geek on the White River. This report describes the effects of combined-sewer overflows and urban runoff on the water quality of Fall Creek during summer 1987 by comparing the water quality during base flow with that during storm runoff and by comparing water quality in the urbanized area with that in the less urbanized area upstream from the combined-sewer overflows. Data were collected at three streamflow-gaging stations located upstream from, downstream from, and in the middle of 27 combined-sewer overflows on Fall Creek. The most downstream station also was immediately downstream from the discharge of filter backwash from a water-treatment plant for public supply.

  3. Identification of controlling factors for the initiation of corrosion of fresh concrete sewers.

    Science.gov (United States)

    Jiang, Guangming; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

    2015-09-01

    The development of concrete corrosion in new sewer pipes undergoes an initiation process before reaching an active corrosion stage. This initiation period is assumed to last several months to years but the key factors affecting the process, and its duration, are not well understood. This study is therefore focused on this initial stage of the corrosion process and the effect of key environmental factors. Such knowledge is important for the effective management of corrosion in new sewers, as every year of life extension of such systems has a very high financial benefit. This long-term (4.5 year) study has been conducted in purpose-built corrosion chambers that closely simulated the sewer environment, but with control of three key environmental factors being hydrogen sulfide (H2S) gas phase concentration, relative humidity and air temperature. Fresh concrete coupons, cut from an industry-standard sewer pipe, were exposed to the corrosive conditions in the chambers, both in the gas phase and partially submerged in wastewater. A total of 36 exposure conditions were investigated to determine the controlling factors by regular retrieval of concrete coupons for detailed analysis of surface pH, sulfur compounds (elemental sulfur and sulfate) and concrete mass loss. Corrosion initiation times were thus determined for different exposure conditions. It was found that the corrosion initiation time of both gas-phase and partially-submerged coupons was positively correlated with the gas phase H2S concentration, but only at levels of 10 ppm or below, indicating that sulfide oxidation rate rather than the H2S concentration was the limiting factor during the initiation stage. Relative humidity also played a role for the corrosion initiation of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as these coupons were in direct contact with the sewage and hence did have sufficient moisture to enable the microbial processes to proceed. The

  4. Clean Energy Solutions Center Services

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

  5. Constructed Wetlands for Treatment of Combined Sewer Overflow in the US: A Review of Design Challenges and Application Status

    OpenAIRE

    Wendong Tao; James S. Bays; Daniel Meyer; Smardon, Richard C.; Zeno F. Levy

    2014-01-01

    As combined sewer systems and centralized wastewater treatment facilities age, many communities in the world are challenged by management of combined sewer overflow (CSO). Constructed wetlands are considered to be one of the green infrastructure solutions to CSOs in the US. Despite the wide application of constructed wetlands to different types of wastewaters, the stochastic and intermittent nature of CSO presents challenges for design and performance assessment of constructed wetlands. This ...

  6. Multi-stage cleaning plant

    Energy Technology Data Exchange (ETDEWEB)

    Kullendorff, A.; Wikner, J.

    1980-12-09

    A cleaning plant positioned within an annular fluidized bed combustion chamber is divided into a plurality of separate cleaning stages, wherein a first stage is located adjacent the fluidized bed and additional stages are arranged within the first stage. Each stage comprises a plurality of separate cleaning devices which act in parallel, while cleaning devices of different stages act in series to remove debris from the combustion gases that exit from the fluidized bed combustion chamber.

  7. Sustainable development with clean coal

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    This paper discusses the opportunities available with clean coal technologies. Applications include new power plants, retrofitting and repowering of existing power plants, steelmaking, cement making, paper manufacturing, cogeneration facilities, and district heating plants. An appendix describes the clean coal technologies. These include coal preparation (physical cleaning, low-rank upgrading, bituminous coal preparation); combustion technologies (fluidized-bed combustion and NOx control); post-combustion cleaning (particulate control, sulfur dioxide control, nitrogen oxide control); and conversion with the integrated gasification combined cycle.

  8. Resilience of sewage services to climate change uncertainty: analysis of the management of sewer overflows in two Parisian suburban areas.

    Science.gov (United States)

    Rioust, E.; Deroubaix, J. F.; Barroca, B.; Bonierbale, T.; de Gouvello, B.; Deutsch, J. C.; Hubert, G.

    2009-04-01

    This paper considers the resilience perspective as an approach for understanding social and political vulnerabilities of urban services. The authors examine to what extend uncertainty due to climate change may affect the resilience of these urban services. The resilience perspective is increasingly used for analysing social groups' capacities to adapt to and live with disturbances. A lot of work on resilience has focused on the capacity to absorb shocks and still maintain functions. But there is also another aspect of resilience, which leads to take into account systems vulnerabilities and to aim at understanding their equilibrium and re-organization capacity. The purpose with this paper is to assess sewage systems capacities to adapt to climate change. Indeed, climate change could cause an increase of extreme rain events and, as a matter of consequence, an increase of sewer overflows and flooding of urbanised areas. Sewer systems have to cope with this change that may gravely affect urban planning. In recent studies of political science, risk management has been considered as a public policy involving and resulting from complex social, political and technical processes (Gilbert et al. 2003). From this point of view, the management of wastewaters and storm waters has to be considered not only as a technical but also as a political and a social system. Therefore, political science can be a fruitful perspective to understand the stakeholders perceptions of uncertainty and the way they are going to integrate this issue in their practices. The authors analyse the adaptive capacities of two sewer systems located in the Parisian suburban area. The chosen areas are highly populated. Each network is managed within a political and administrative unit called "Département". Both authorities of these "Départements" implement a public sewage service. Nonetheless these networks are connected and part of the greater Paris sewage policy. In both areas a real time control of

  9. Modelling total suspended solids, E. coli and carbamazepine, a tracer of wastewater contamination from combined sewer overflows

    Science.gov (United States)

    Pongmala, Khemngeun; Autixier, Laurène; Madoux-Humery, Anne-Sophie; Fuamba, Musandji; Galarneau, Martine; Sauvé, Sébastien; Prévost, Michèle; Dorner, Sarah

    2015-12-01

    Urban source water protection requires knowledge of sources of fecal contamination upstream of drinking water intakes. Combined and sanitary sewer overflows (CSOs and SSOs) are primary sources of microbiological contamination and wastewater micropollutants (WWMPs) in urban water supplies. To quantify the impact of sewer overflows, predictive simulation models are required and have not been widely applied for microbial contaminants such as fecal indicator bacteria and pathogens in urban drainage networks. The objective of this study was to apply a simulation model to estimate the dynamics of three contaminants in sewer overflows - total suspended solids, Escherichia coli (E. coli) and carbamazepine, a WWMP. A mixed combined and pseudo-sanitary drainage network in Québec, Canada was studied and modelled for a total of 7 events for which water quality data were available. Model results were significantly correlated with field water quality data. The model confirmed that the contributions of E. coli from runoff and sewer deposits were minor and their dominant source was from sewage. In contrast, the main sources of total suspended solids were stormwater runoff and sewer resuspension. Given that it is not present in stormwater, carbamazepine was found to be a useful stable tracer of sewage contributions to total contaminant loads and also provided an indication of the fraction of total suspended solids originating from sewer deposits because of its similar response to increasing flowrates.

  10. Cleaning of Free Machining Brass

    Energy Technology Data Exchange (ETDEWEB)

    Shen, T

    2005-12-29

    We have investigated four brightening treatments proposed by two cleaning vendors for cleaning free machining brass. The experimental results showed that none of the proposed brightening treatments passed the swipe test. Thus, we maintain the recommendation of not using the brightening process in the cleaning of free machining brass for NIF application.

  11. A Clean Market

    Institute of Scientific and Technical Information of China (English)

    MAGGIECHEN

    2004-01-01

    If you have US$1 million, do you invest in car production or cleaning car emissions? More cars than ever are hitting the roads and demand is rising.Cleaner cars are being called for, as the government strives to reduce car emission. So there is an obvious market both for cars and for new emission control technologies.Theoretically, you should make money by investing in either of them in China today.

  12. Clean Power on Tap

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China adopts the most advanced nuclear power technologies to meet long-term energy needs Nuclear power has taken center stage in China’s nationwide cam-paign to develop new and clean energy sources. In the latest effort, Chinese state-owned nuclear power giants invested over 40 billion yuan ($5.86 billion) as an initial funding injection to build a new plant under the

  13. CLEAN: CLustering Enrichment ANalysis

    Directory of Open Access Journals (Sweden)

    Medvedovic Mario

    2009-07-01

    Full Text Available Abstract Background Integration of biological knowledge encoded in various lists of functionally related genes has become one of the most important aspects of analyzing genome-wide functional genomics data. In the context of cluster analysis, functional coherence of clusters established through such analyses have been used to identify biologically meaningful clusters, compare clustering algorithms and identify biological pathways associated with the biological process under investigation. Results We developed a computational framework for analytically and visually integrating knowledge-based functional categories with the cluster analysis of genomics data. The framework is based on the simple, conceptually appealing, and biologically interpretable gene-specific functional coherence score (CLEAN score. The score is derived by correlating the clustering structure as a whole with functional categories of interest. We directly demonstrate that integrating biological knowledge in this way improves the reproducibility of conclusions derived from cluster analysis. The CLEAN score differentiates between the levels of functional coherence for genes within the same cluster based on their membership in enriched functional categories. We show that this aspect results in higher reproducibility across independent datasets and produces more informative genes for distinguishing different sample types than the scores based on the traditional cluster-wide analysis. We also demonstrate the utility of the CLEAN framework in comparing clusterings produced by different algorithms. CLEAN was implemented as an add-on R package and can be downloaded at http://Clusteranalysis.org. The package integrates routines for calculating gene specific functional coherence scores and the open source interactive Java-based viewer Functional TreeView (FTreeView. Conclusion Our results indicate that using the gene-specific functional coherence score improves the reproducibility of the

  14. Effect of two cleaning processes for bone allografts on gentamicin impregnation and in vitro antibiotic release.

    Science.gov (United States)

    Coraça-Huber, D C; Hausdorfer, J; Fille, M; Steidl, M; Nogler, M

    2013-06-01

    Bone allografts are a useful and sometimes indispensable tool for the surgeon to repair bone defects. Microbial contamination is a major reason for discarding allografts from bone banks. To improve the number of safe allografts, we suggest chemical cleaning of the grafts followed by antibiotic impregnation. Comparison of two chemical cleaning processes for bone allografts aiming for antibiotic impregnation and consequently delivery rates in vitro. Bone chips of 5-10 mm were prepared from human femoral heads. Two cleaning methods (cleaning A and cleaning B) based on solutions containing hydrogen peroxide, paracetic acid, ethanol and biological detergent were carried out and compared. After the cleaning processes, the bone chips were impregnated with gentamicin. Bacillus subtilis bioassay was used to determine the gentamicin release after intervals of 1-7 days. Differences were compared with non-parametric Mann-Whitney U tests. The zones of inhibition obtained from the bone grafts cleaned with both cleaning processes were similar between the groups. The concentration of the released antibiotic was decreasing gradually over time, following a similar pattern for both groups. The cleaning procedure A as well as the cleaning procedure B for bone allografts allowed the impregnation with gentamicin powder in the same concentrations in both groups. The delivery of gentamicin was similar for both groups. Both cleaning procedures were easy to be carried out, making them suitable for routine use at the bone banks.

  15. DNA repair. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Setlow, R.

    1978-01-01

    Some topics discussed are as follows: difficulty in extrapolating data from E. coli to mammalian systems; mutations caused by UV-induced changes in DNA; mutants deficient in excision repair; other postreplication mechanisms; kinds of excision repair systems; detection of repair by biochemical or biophysical means; human mutants deficient in repair; mutagenic effects of UV on XP cells; and detection of UV-repair defects among XP individuals. (HLW)

  16. Clean steels for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Gelles, D.S.

    1995-03-01

    Fusion energy production has an inherent advantage over fission: a fuel supply with reduced long term radioactivity. One of the leading candidate materials for structural applications in a fusion reactor is a tungsten stabilized 9% chromium Martensitic steel. This alloy class is being considered because it offers the opportunity to maintain that advantage in the reactor structure as well as provide good high temperature strength and radiation induced swelling and embrittlement resistance. However, calculations indicate that to obtain acceptable radioactivity levels within 500 years after service, clean steel will be required because the niobium impurity levels must be kept below about 2 appm and nickel, molybdenum, nitrogen, copper, and aluminum must be intentionally restricted. International efforts are addressing the problems of clean steel production. Recently, a 5,000 kg heat was vacuum induction melted in Japan using high purity commercial raw materials giving niobium levels less than 0.7 appm. This paper reviews the need for reduced long term radioactivity, defines the advantageous properties of the tungsten stabilized Martensitic steel class, and describes the international efforts to produce acceptable clean steels.

  17. Saltstone Clean Cap Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C

    2005-04-22

    The current operation strategy for using Saltstone Vault 4 to receive 0.2 Ci/gallon salt solution waste involves pouring a clean grout layer over the radioactive grout prior to initiating pour into another cell. This will minimize the radiating surface area and reduce the dose rate at the vault and surrounding area. The Clean Cap will be used to shield about four feet of Saltstone poured into a Z-Area vault cell prior to moving to another cell. The minimum thickness of the Clean Cap layer will be determined by the cesium concentration and resulting dose levels and it is expected to be about one foot thick based on current calculations for 0.1 Ci Saltstone that is produced in the Saltstone process by stabilization of 0.2 Ci salt solution. This report documents experiments performed to identify a formulation for the Clean Cap. Thermal transient calculations, adiabatic temperature rise measurements, pour height, time between pour calculations and shielding calculations were beyond the scope and time limitations of this study. However, data required for shielding calculations (composition and specific gravity) are provided for shielding calculations. The approach used to design a Clean Cap formulation was to produce a slurry from the reference premix (10/45/45 weight percent cement/slag/fly ash) and domestic water that resembled as closely as possible the properties of the Saltstone slurry. In addition, options were investigated that may offer advantages such as less bleed water and less heat generation. The options with less bleed water required addition of dispersants. The options with lower heat contained more fly ash and less slag. A mix containing 10/45/45 weight percent cement/slag/fly ash with a water to premix ratio of 0.60 is recommended for the Clean Cap. Although this mix may generate more than 3 volume percent standing water (bleed water), it has rheological, mixing and flow properties that are similar to previously processed Saltstone. The recommended

  18. Cesium and strontium loads into a combined sewer system from rainwater runoff.

    Science.gov (United States)

    Kamei-Ishikawa, Nao; Yoshida, Daiki; Ito, Ayumi; Umita, Teruyuki

    2016-12-01

    In this study, combined sewage samples were taken with time in several rain events and sanitary sewage samples were taken with time in dry weather to calculate Cs and Sr loads to sewers from rainwater runoff. Cs and Sr in rainwater were present as particulate forms at first flush and the particulate Cs and Sr were mainly bound with inorganic suspended solids such as clay minerals in combined sewage samples. In addition, multiple linear regression analysis showed Cs and Sr loads from rainwater runoff could be estimated by the total amount of rainfall and antecedent dry weather days. The variation of the Sr load from rainwater to sewers was more sensitive to total amount of rainfall and antecedent dry weather days than that of the Cs load.

  19. Case study of a fast propagating bacteriogenically induced concrete corrosion in an Austrian sewer system

    Science.gov (United States)

    Grengg, Cyrill; Mittermayr, Florian; Baldermann, Andre; Böttcher, Michael; Leis, Albrecht; Koraimann, Günther; Dietzel, Martin

    2015-04-01

    Reaction mechanisms leading to microbially induced concrete corrosion (MICC) are highly complex and often not fully understood. The aim of the present case study is to contribute to a deeper understanding of reaction paths, environmental controls, and corrosion rates related to MICC in a modern Austrian sewer system by introducing an advanced multi proxy approach that comprises gaseous, hydro-geochemical, bacteriological, and mineralogical analyses. Various crucial parameters for detecting alteration features were determined in the field and laboratory, including (i) temperature, pH, alkalinity, chemical compositions of the solutions, (ii) chemical and mineralogical composition of solids, (iii) bacterial analysis, and (iv) concentrations of gaseous H2S, CH4 and CO2 within the sewer pipe atmosphere. An overview of the field site and analytical results, focusing on reaction mechanisms causing the corrosion, as well as possible remediation strategies will be presented.

  20. Reducing pathogens in combined sewer overflows using ozonation or UV irradiation.

    Science.gov (United States)

    Tondera, Katharina; Klaer, Kassandra; Gebhardt, Jens; Wingender, Jost; Koch, Christoph; Horstkott, Marina; Strathmann, Martin; Jurzik, Lars; Hamza, Ibrahim Ahmed; Pinnekamp, Johannes

    2015-11-01

    Fecal contamination of water resources is a major public health concern in densely populated areas since these water bodies are used for drinking water production or recreational purposes. A main source of this contamination originates from combined sewer overflows (CSOs) in regions with combined sewer systems. Thus, the treatment of CSO discharges is urgent. In this study, we explored whether ozonation or UV irradiation can efficiently reduce pathogenic bacteria, viruses, and protozoan parasites in CSOs. Experiments were carried out in parallel settings at the outflow of a stormwater settling tank in the Ruhr area, Germany. The results showed that both techniques reduce most hygienically relevant bacteria, parasites and viruses. Under the conditions tested, ozonation yielded lower outflow values for the majority of the tested parameters.

  1. EMISSION OF POLLUTANTS FROM COMBINED SEWER OVERFLOWS IN THE ASPECT OF THEIR IMPACT ON A RECEIVER

    Directory of Open Access Journals (Sweden)

    Agnieszka Brzezińska

    2016-06-01

    Full Text Available Increased efficiency of wastewater treatment highlights the role of combined sewer overflows in deterioration the quality of water receiver because pollutant loads discharged by them have a growing share in entire load discharged into a receiver. The article contains the results of the wastewater quality analyzes emitted into the receiver from the three studied combined sewer overflows of the city of Lodz. The results demonstrated a large variations in the pollutant concentration directed to the receiver during rain events. The possible impact of untreated wastewater emitted to the receiver is also presented. Apart from the pollution of the receiver, mainly by organic and nutrient substances, the microbiological contamination which is dangerous for people using the river as a recreation area and for animals that use a water receiver as a source of drinking water, should be taken into particular attention.

  2. Bacterial diversity impacts as a result of combined sewer overflow in a polluted waterway

    Directory of Open Access Journals (Sweden)

    O. Calderon

    2017-12-01

    Full Text Available Newtown Creek is an industrial waterway and former tidal wetland in New York City. It is one of the most polluted water bodies in the United States and was designated as a superfund site in 2010. For over a century, organic compounds, heavy metals, and other forms of industrial pollution have disrupted the creek’s environment. The creek is also impacted by discharges from twenty combined sewer overflow pipes, which may deposit raw sewage or partially treated wastewater directly into the creek during heavy or sustained rain events. Combined sewer overflow events and associated nutrient over-enrichment at the creek drive eutrophication and subsequent hypoxia. At the current study, three sites were sampled one week apart during a dry period and a wet period, where indication of a combined sewage overflow event could be detected. 16s rRNA high-throughput sequencing from these three sites collectively yielded over 1000 species of bacteria belonging to twenty-two classes. Based on these data, it is hypothesized that differences identified in the microbiome on wet versus dry days are as a result of combined sewage overflow, street runoff, and additional fluctuations in the creek’s environment associated with rain. It was found that after a combined sewer overflows event, the levels of Gamma Proteobacteria increased while the levels of Actinobacteria decreased. However, levels of bacteria stayed relatively unchanged at a site further away from combined sewer overflows discharge. Species found in Newtown Creek include pelagic, marine, human and animal pathogens, hydrocarbonoclastic, and other environmental microbes.

  3. Arc Based Ant Colony Optimization Algorithm for optimal design of gravitational sewer networks

    Directory of Open Access Journals (Sweden)

    R. Moeini

    2017-06-01

    Full Text Available In this paper, constrained and unconstrained versions of a new formulation of Ant Colony Optimization Algorithm (ACOA named Arc Based Ant Colony Optimization Algorithm (ABACOA are augmented with the Tree Growing Algorithm (TGA and used for the optimal layout and pipe size design of gravitational sewer networks. The main advantages offered by the proposed ABACOA formulation are proper definition of heuristic information, a useful component of the ant-based algorithms, and proper trade-off between the two conflicting search attributes of exploration and exploitation. In both the formulations, the TGA is used to incrementally construct feasible tree-like layouts out of the base layout. In the first formulation, unconstrained version of ABACOA is used to determine the nodal cover depths of sewer pipes while in the second formulation, a constrained version of ABACOA is used to determine the nodal cover depths of sewer pipes which satisfy the pipe slopes constraint. Three different methods of cut determination are also proposed to complete the construction of a tree-like network containing all base layout pipes, here. The proposed formulations are used to solve three test examples of different scales and the results are presented and compared with other available results in the literature. Comparison of the results shows that best results are obtained using the third cutting method in both the formulations. In addition, the results indicate the ability of the proposed methods and in particular the constrained version of ABACOA equipped with TGA to solve sewer networks design optimization problem. To be specific, the constrained version of ABACOA has been able to produce results 0.1%, 1% and 2.1% cheaper than those obtained by the unconstrained version of ABACOA for the first, second and the third test examples, respectively.

  4. Sewer-mining: A water reuse option supporting circular economy, public service provision and entrepreneurship.

    Science.gov (United States)

    Makropoulos, C; Rozos, E; Tsoukalas, I; Plevri, A; Karakatsanis, G; Karagiannidis, L; Makri, E; Lioumis, C; Noutsopoulos, C; Mamais, D; Rippis, C; Lytras, E

    2017-07-17

    Water scarcity, either due to increased urbanisation or climatic variability, has motivated societies to reduce pressure on water resources mainly by reducing water demand. However, this practice alone is not sufficient to guarantee the quality of life that high quality water services underpin, especially within a context of increased urbanisation. As such, the idea of water reuse has been gaining momentum for some time and has recently found a more general context within the idea of the Circular Economy. This paper is set within the context of an ongoing discussion between centralized and decentralized water reuse techniques and the investigation of trade-offs between efficiency and economic viability of reuse at different scales. Specifically, we argue for an intermediate scale of a water reuse option termed 'sewer-mining', which could be considered a reuse scheme at the neighbourhood scale. We suggest that sewer mining (a) provides a feasible alternative reuse option when the geography of the wastewater treatment plant is problematic, (b) relies on mature treatment technologies and (c) presents an opportunity for Small Medium Enterprises (SME) to be involved in the water market, securing environmental, social and economic benefits. To support this argument, we report on a pilot sewer-mining application in Athens, Greece. The pilot, integrates two subsystems: a packaged treatment unit and an information and communications technology (ICT) infrastructure. The paper reports on the pilot's overall performance and critically evaluates the potential of the sewer-mining idea to become a significant piece of the circular economy puzzle for water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Stream restoration and sewers impact sources and fluxes of water, carbon, and nutrients in urban watersheds

    Science.gov (United States)

    Pennino, Michael J.; Kaushal, Sujay S.; Mayer, Paul M.; Utz, Ryan M.; Cooper, Curtis A.

    2016-08-01

    An improved understanding of sources and timing of water, carbon, and nutrient fluxes associated with urban infrastructure and stream restoration is critical for guiding effective watershed management globally. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P) shift in response to differences in urban stream restoration and sewer infrastructure. We compared an urban restored stream with two urban degraded streams draining varying levels of urban development and one stream with upland stormwater management systems over a 3-year period. We found that there was significantly decreased peak discharge in response to precipitation events following stream restoration. Similarly, we found that the restored stream showed significantly lower (p exported most carbon, nitrogen, and phosphorus at relatively lower streamflow than the two more urban catchments, which exported most carbon and nutrients at higher streamflow. Annual exports of total carbon (6.6 ± 0.5 kg ha-1 yr-1), total nitrogen (4.5 ± 0.3 kg ha-1 yr-1), and total phosphorus (161 ± 15 kg ha-1 yr-1) were significantly lower in the restored stream compared to both urban degraded streams (p exports. However, nitrate isotope data suggested that 55 ± 1 % of the nitrate in the urban restored stream was derived from leaky sanitary sewers (during baseflow), statistically similar to the urban degraded streams. These isotopic results as well as additional tracers, including fluoride (added to drinking water) and iodide (contained in dietary salt), suggested that groundwater contamination was a major source of urban nutrient fluxes, which has been less considered compared to upland sources. Overall, leaking sewer pipes are a problem globally and our results suggest that combining stream restoration with restoration of aging sewer pipes can be critical to more effectively minimizing urban nonpoint nutrient sources. The sources, fluxes, and flowpaths of groundwater

  6. Assessment of pollutant load emission from combined sewer overflows based on the online monitoring

    OpenAIRE

    Brzezińska, Agnieszka; Zawilski, Marek; Sakson, Grażyna

    2016-01-01

    Cities equipped with combined sewer systems discharge during wet weather a lot of pollutants into receiving waters by combined storm overflows (CSOs). According to the Polish legislation, CSOs should be activated no more than ten times per year, but in Lodz, most of the 18 existing CSOs operate much more frequently. To assess the pollutant load emitted by one of the existing CSOs, the sensors for measuring the concentration of total suspended solids (SOLITAX sc) and dissolved chemical oxygen ...

  7. Effects of combined sewer overflows on a periurban stream ecosystem: Methodological approach

    OpenAIRE

    Breil, P.; Lafont, M.; Vivier, A.; Namour, P.; Schmitt, L.

    2007-01-01

    International audience; Here we develop from a long term field experiment an assessment method of interstitial fauna resilience to combined sewer overflows (CSOs) effect. We address the case of small water courses for which the ratio of CSOs to natural flow can be 1 to much more. Biotic material was collected in the benthic and hyporheic layers. Biotic material focussed mainly on oligocheates species whose diversity, species category and abundance are resumed into metrics, called functional t...

  8. Tracking artificial sweeteners and pharmaceuticals introduced into urban groundwater by leaking sewer networks.

    Science.gov (United States)

    Wolf, Leif; Zwiener, Christian; Zemann, Moritz

    2012-07-15

    There is little quantitative information on the temporal trends of pharmaceuticals and other emerging compounds, including artificial sweeteners, in urban groundwater and their suitability as tracers to inform urban water management. In this study, pharmaceuticals and artificial sweeteners were monitored over 6 years in a shallow urban groundwater body along with a range of conventional sewage tracers in a network of observation wells that were specifically constructed to assess sewer leakage. Out of the 71 substances screened, 24 were detected at above the analytical detection limit. The most frequent compounds were the iodinated X-ray contrast medium amidotrizoic acid (35.3%), the anticonvulsant carbamazepine (33.3%) and the artificial sweetener acesulfame (27.5%), while all other substances occurred in less than 10% of the screened wells. The results from the group of specifically constructed focus wells within 10 m of defective sewers confirmed sewer leaks as being a major entrance pathway into the groundwater. The spatial distribution of pharmaceuticals and artificial sweeteners corresponds well with predictions by pipeline leakage models, which operate on optical sewer condition monitoring data and hydraulic information. Correlations between the concentrations of carbamazepine, iodinated X-ray contrast media and artificial sweeteners were weak to non-existent. Peak concentrations of up to 4130 ng/l of amidotrizoic acid were found in the groundwater downstream of the local hospital. The analysis of 168 samples for amidotrizoic acid, taken at 5 different occasions, did not show significant temporal trends for the years 2002-2008, despite changed recommendations in the medical usage of amidotrizoic acid. The detailed results show that the current mass balance approaches for urban groundwater bodies must be adapted to reflect the spatially distributed leaks and the variable wastewater composition in addition to the lateral and horizontal groundwater fluxes.

  9. Effects of Contamination and Cleaning on Parachute Structural Textile Elements

    Science.gov (United States)

    Mollmann, Catherine

    2017-01-01

    Throughout their lifecycle, parachute textiles come into contact with various other substances. This contact may occur during manufacturing and repair, storage and transportation, packing, or actual use. While this interaction does not always result in negative repercussions, it may cause a loss in material strength. This paper examines the strength degradation due to several contaminants as well as the effects of cleaning agents on common parachute materials. Materials tested were: Kevlar cord and webbing, Nylon broadcloth and webbing, and Vectran cord; all of these constitute the major structural elements for CPAS (Capsule Parachute Assembly System), the parachute system for the NASA Orion Crew Module. Contaminants tested were: sewing machine oil, dried stamping ink, dirt, basting glue, Sergene, and rust. Recommendations for cleaning (or not cleaning) these materials with respect to each of the contaminants are given in this paper, as well as recommendations for future tests.

  10. Alternatives to Organic Solvents in Industrial Cleaning Processes

    DEFF Research Database (Denmark)

    Jacobsen, Thomas

    1998-01-01

    cleaning agents in offset printing companies instead of volatile, toxic organic solvents. The present study is based on a project with the aim of defining other industrial processes, where organic solvents used for cleaning or degreasing can be replaced by non-volatile, low-toxic products, which are based...... on esters from fatty acids of vegetable origin (vegetable esters - VE).The study indicates that industrial cleaning/degreasing with organic solvents may be substituted with VEs on metal surfaces and on some coated surfaces, in manufacture of paints and inks, use of paints, use of inks (printing), metal...... industry, and vehicle repair and maintenance. There are, however, other elements that influence the possibility to substitute. The requirements to the resulting surface, depending on the following treatment of the surface. The character of the soilings to be removed. The possible presence of other...

  11. Evaluation of exposure pathways to man from disposal of radioactive materials into sanitary sewer systems

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.E. Jr.; Parkhurst, M.A.; Aaberg, R.L.; Rhoads, K.C.; Hill, R.L.; Martin, J.B. [Pacific Northwest Lab., Richland, WA (United States)

    1992-05-01

    In accordance with 10 CFR 20, the US Nuclear Regulatory Commission (NRC) regulates licensees` discharges of small quantities of radioactive materials into sanitary sewer systems. This generic study was initiated to examine the potential radiological hazard to the public resulting from exposure to radionuclides in sewage sludge during its treatment and disposal. Eleven scenarios were developed to characterize potential exposures to radioactive materials during sewer system operations and sewage sludge treatment and disposal activities and during the extended time frame following sewage sludge disposal. Two sets of deterministic dose calculations were performed; one to evaluate potential doses based on the radionuclides and quantities associated with documented case histories of sewer system contamination and a second, somewhat more conservative set, based on theoretical discharges at the maximum allowable levels for a more comprehensive list of 63 radionuclides. The results of the stochastic uncertainty and sensitivity analysis were also used to develop a collective dose estimate. The collective doses for the various radionuclides and scenarios range from 0.4 person-rem for {sup 137}Cs in Scenario No. 5 (sludge incinerator effluent) to 420 person-rem for {sup 137}Cs in Scenario No. 3 (sewage treatment plant liquid effluent). None of the 22 scenario/radionuclide combinations considered have collective doses greater than 1000 person-rem/yr. However, the total collective dose from these 22 combinations was found to be about 2100 person-rem.

  12. An obstacle to China's WWTPs: the COD and BOD standards for discharge into municipal sewers.

    Science.gov (United States)

    Liao, Zhenliang; Hu, Tiantian; Roker, Scott Albert C

    2015-11-01

    In 2001, a construction campaign regarding wastewater treatment plants (WWTPs) occurred in China. Unfortunately, the treatment has not yet achieved anticipated effectiveness. A critical reason for this is that the influent chemical oxygen demand (COD) and biochemical oxygen demand (BOD) concentrations in WWTPs are unacceptably low. This paper indicates that a fundamental, but commonly overlooked contributing factor to this problem is that a large portion of easily degradable COD and BOD is degraded prematurely before entering municipal sewers, and this is directly correlated to China's standards for pollutant discharging into municipal sewers. This perspective is further unfolded through retrospection of the history of Chinese wastewater treatment and the investigation of standards among developed zones and districts. This paper suggests that in China, the standards for pollutant discharging into municipal sewers should be relaxed. Meanwhile, unnecessary pretreatment of COD and BOD should cease for the purpose of ensuring that easily degradable COD and BOD can be transferred to WWTPs to improve treatment efficiency. Moreover, additional alternatives are presented to resolve this problem.

  13. Constructed Wetlands for Combined Sewer Overflow Treatment—Comparison of German, French and Italian Approaches

    Directory of Open Access Journals (Sweden)

    Daniel Meyer

    2012-12-01

    Full Text Available Combined sewer systems are designed to transport stormwater surface run off in addition to the dry weather flows up to defined limits. In most European countries, hydraulic loads greater than the design flow are discharged directly into receiving water bodies, with minimal treatment (screening, sedimentation, or with no treatment at all. One feasible solution to prevent receiving waters from strong negative impacts seems to be the application of vertical flow constructed wetlands. In Germany, first attempts to use this ecological technology were recognized in early 1990s. Since then, further development continued until a high level of treatment performance was reached. During recent years the national “state-of-the-art” (defined in 2005 was adapted in other European countries, including France and Italy. Against the background of differing national requirements in combined sewer system design, substantial developmental steps were taken. The use of coarser filter media in combination with alternating loadings of separated filter beds allows direct feedings with untreated combined runoff. Permanent water storage in deep layers of the wetland improves the system’s robustness against extended dry periods, but contains operational risks. Besides similar functions (but different designs and layouts, correct dimensioning of all approaches suffers from uncertainties in long-term rainfall predictions as well as inside sewer system simulation tools.

  14. Clean electricity from photovoltaics

    CERN Document Server

    Green, Martin A

    2015-01-01

    The second edition of Clean Electricity from Photovoltaics , first published in 2001, provides an updated account of the underlying science, technology and market prospects for photovoltaics. All areas have advanced considerably in the decade since the first edition was published, which include: multi-crystalline silicon cell efficiencies having made impressive advances, thin-film CdTe cells having established a decisive market presence, and organic photovoltaics holding out the prospect of economical large-scale power production. Contents: The Past and Present (M D Archer); Limits to Photovol

  15. Clean Room Apparel

    Science.gov (United States)

    1989-01-01

    American Hospital Supply Corporation (AHSC), Baxter Healthcare Corporation's predecessor, used the NASA informational base on contamination control technology to improve industrial contamination control technology. When a study determined that microscopic body particles escaping through tiny "windows" in woven garments worn by workers were the greatest source of contamination, AHSC developed TYVEK. This non-woven material filters 99% of all particulate matter larger than half a micron. Baxter Healthcare added a polyimide coating which seals and ties down any loose fibers, providing greater durability. Stress points along seams have been minimized to make the garment almost tearproof. Micro-Clean 212 garments are individually packaged and disposable.

  16. Flue Gas Cleaning

    DEFF Research Database (Denmark)

    Fehrmann, Rasmus

    2014-01-01

    and sulfuric acid in the atmosphere causing precipitation of acid rain resulting in death of forests and destruction of buildings and monuments in addition to human health problems. The most common state-of-the-art methods applied today industrially for cleaning of flue gases will be addressed, including wet......-time. But the problems may also be attacked by new materials like supported ionic liquid phase (SILP) gas absorbers where the pollutants may be selectively absorbed, desorbed and finally converted to useful mineral acids of commercial grade – really a green waste-to-value approach that we persue instead...

  17. EPA, Seattle truck repair firm settle water pollution case

    Science.gov (United States)

    (SEATTLE - May 13, 2015) Western Peterbilt, LLC, a Seattle truck sales and repair shop, has reached a settlement with the U.S. Environmental Protection Agency stemming from violations of the federal Clean Water Act. As part of the settlement, the company h

  18. Water Quality of Combined Sewer Overflows, Stormwater, and Streams, Omaha, Nebraska, 2006-07

    Science.gov (United States)

    Vogel, Jason R.; Frankforter, Jill D.; Rus, David L.; Hobza, Christopher M.; Moser, Matthew T.

    2009-01-01

    The U.S. Geological Survey, in cooperation with the City of Omaha, investigated the water quality of combined sewer overflows, stormwater, and streams in the Omaha, Nebraska, area by collecting and analyzing 1,175 water samples from August 2006 through October 2007. The study area included the drainage area of Papillion Creek at Capeheart Road near Bellevue, Nebraska, which encompasses the tributary drainages of the Big and Little Papillion Creeks and Cole Creek, along with the Missouri River reach that is adjacent to Omaha. Of the 101 constituents analyzed during the study, 100 were detected in at least 1 sample during the study. Spatial and seasonal comparisons were completed for environmental samples. Measured concentrations in stream samples were compared to water-quality criteria for pollutants of concern. Finally, the mass loads of water-quality constituents in the combined sewer overflow discharges, stormwater outfalls, and streams were computed and compared. The results of the study indicate that combined sewer overflow and stormwater discharges are affecting the water quality of the streams in the Omaha area. At the Papillion Creek Basin sites, Escherichia coli densities were greater than 126 units per 100 milliliters in 99 percent of the samples (212 of 213 samples analyzed for Escherichia coli) collected during the recreational-use season from May through September (in 2006 and 2007). Escherichia coli densities in 76 percent of Missouri River samples (39 of 51 samples) were greater than 126 units per 100 milliliters in samples collected from May through September (in 2006 and 2007). None of the constituents with human health criteria for consumption of water, fish, and other aquatic organisms were detected at levels greater than the criteria in any of the samples collected during this study. Total phosphorus concentrations in water samples collected in the Papillion Creek Basin were in excess of the U.S. Environmental Protection Agency's proposed

  19. International Clean Energy Coalition

    Energy Technology Data Exchange (ETDEWEB)

    Erin Skootsky; Matt Gardner; Bevan Flansburgh

    2010-09-28

    In 2003, the National Association of Regulatory Utility Commissioners (NARUC) and National Energy Technology Laboratories (NETL) collaboratively established the International Clean Energy Coalition (ICEC). The coalition consisting of energy policy-makers, technologists, and financial institutions was designed to assist developing countries in forming and supporting local approaches to greenhouse gas mitigation within the energy sector. ICEC's work focused on capacity building and clean energy deployment in countries that rely heavily on fossil-based electric generation. Under ICEC, the coalition formed a steering committee consisting of NARUC members and held a series of meetings to develop and manage the workplan and define successful outcomes for the projects. ICEC identified India as a target country for their work and completed a country assessment that helped ICEC build a framework for discussion with Indian energy decisionmakers including two follow-on in-country workshops. As of the conclusion of the project in 2010, ICEC had also conducted outreach activities conducted during United Nations Framework Convention on Climate Change (UNFCCC) Ninth Conference of Parties (COP 9) and COP 10. The broad goal of this project was to develop a coalition of decision-makers, technologists, and financial institutions to assist developing countries in implementing affordable, effective and resource appropriate technology and policy strategies to mitigate greenhouse gas emissions. Project goals were met through international forums, a country assessment, and in-country workshops. This project focused on countries that rely heavily on fossil-based electric generation.

  20. Pectus excavatum repair

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002949.htm Pectus excavatum repair To use the sharing features on this page, please enable JavaScript. Pectus excavatum repair is surgery to correct pectus excavatum . This ...

  1. When "Other" Initiate Repair.

    Science.gov (United States)

    Schegloff, Emanuel A.

    2000-01-01

    Elaborates on the locus of other-initiated repair, and reports on a number of environments in which others initiate repair turns later than the one directly following the trouble-source turn. Describes several ways that other initiation of repair, which occurs in next-turn position, may be delayed within that position. (Author/VWL)

  2. Clean coal technologies market potential

    Energy Technology Data Exchange (ETDEWEB)

    Drazga, B. (ed.)

    2007-01-30

    Looking at the growing popularity of these technologies and of this industry, the report presents an in-depth analysis of all the various technologies involved in cleaning coal and protecting the environment. It analyzes upcoming and present day technologies such as gasification, combustion, and others. It looks at the various technological aspects, economic aspects, and the various programs involved in promoting these emerging green technologies. Contents: Industry background; What is coal?; Historical background of coal; Composition of coal; Types of coal; Environmental effects of coal; Managing wastes from coal; Introduction to clean coal; What is clean coal?; Byproducts of clean coal; Uses of clean coal; Support and opposition; Price of clean coal; Examining clean coal technologies; Coal washing; Advanced pollution control systems; Advanced power generating systems; Pulverized coal combustion (PCC); Carbon capture and storage; Capture and separation of carbon dioxide; Storage and sequestration of carbon dioxide; Economics and research and development; Industry initiatives; Clean Coal Power Initiative; Clean Coal Technology Program; Coal21; Outlook; Case Studies.

  3. Back to Basics: Instrument Cleaning.

    Science.gov (United States)

    Spruce, Lisa

    2017-03-01

    Adequately cleaning and processing surgical instruments may be challenging for perioperative team members; however, the cleaning and processing of instruments are critical steps in making instruments safe to use on patients and achieving an appropriately safe OR environment. Instruments that are cleaned properly have had organic debris and soil removed, rendering them ready for sterilization or disinfection. This Back to Basics article covers the basic steps and considerations for cleaning and processing instruments before sterilization. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  4. Modelling the effects of on-site greywater reuse and low flush toilets on municipal sewer systems.

    Science.gov (United States)

    Penn, R; Schütze, M; Friedler, E

    2013-01-15

    On-site greywater reuse (GWR) and installation of water-efficient toilets (WET) reduce urban freshwater demand. Research on GWR and WET has generally overlooked the effects that GWR may have on municipal sewer systems. This paper discusses and quantifies these effects. The effects of GWR and WET, positive and negative, were studied by modelling a representative urban sewer system. GWR scenarios were modelled and analysed using the SIMBA simulation system. The results show that, as expected, the flow, velocity and proportional depth decrease as GWR increases. Nevertheless, the reduction is not evenly distributed throughout the day but mainly occurs during the morning and evening peaks. Examination of the effects of reduced toilet flush volumes revealed that in some of the GWR scenarios flows, velocities and proportional depths in the sewer were reduced, while in other GWR scenarios discharge volumes, velocities and proportional depths did not change. Further, it is indicated that as a result of GWR and installation of WET, sewer blockage rates are not expected to increase significantly. The results support the option to construct new sewer systems with smaller pipe diameters. The analysis shows that as the penetration of GWR systems increase, and with the installation of WET, concentrations of pollutants also increase. In GWR scenarios (when toilet flush volume is not reduced) the increase in pollutant concentrations is lower than the proportional reduction of sewage flow. Moreover, the results show that the spatial distribution of houses reusing GW does not significantly affect the parameters examined.

  5. Communicating with clean technology

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, S.

    1996-09-01

    The potential role of computer-based communications on energy consumption, sustainable development, and the environment were discussed. Various potential benefits derivable from applications such as teleconferencing, videoconferencing, distance-learning, and teleworking as alternatives to travel by car or plane, data transmission by telefax, e-mail, or the Internet, and the resulting effect on paper consumption were cited as examples of how clean computer technology will have significant impact on energy policy and behaviour. It was contended that even if the environmental benefits are not yet promoted as widely as they should be, the increasing danger of air pollution and ozone depletion, combined with the falling cost of telecommunications, productivity gains and improved bottom lines will force the adoption of computer-based communication by mainstream society. 8 refs.

  6. Ultrasound cleaning of microfilters

    DEFF Research Database (Denmark)

    Hald, Jens; Bjørnø, Irina; Jensen, Leif Bjørnø

    1999-01-01

    The aim of the present work is to develop, design, and manufacture a high-power ultrasound transducer module to be used for preventing the blocking of plastic-based microfilters by organic materials, and possibly to prolong the lifetime of the filters in industry using the cavitation on the surface...... suitable for cleaning of microfilters without damaging the filter structure. The filter surface was studied using an optical microscope before and after the experiment. When high-power ultrasound (max. 75 W/cm2) was applied to the surface of some microfilters, no visible damage was found, while others...... filters were damaged. The results of the laboratory experiments formed background for the final design of an ultrasound transducer module for use by foodstuff filtration plants. [This work was financed by the EU Project WAMBIO PL96-3257 (FAIR Programme).]...

  7. Vigor Clean Tech Inc.

    Energy Technology Data Exchange (ETDEWEB)

    Brubacher-Cressman, Dale [Vigor Clean Tech Inc. (Canada)

    2011-07-01

    On May 5, 2011, the Ontario Waterpower Association hosted the emergent hydro workshop in Peterborough. The first technology presented by Vigor Clean Tech Inc. was a system with a vertical axis which is supported by a floating structure and can provide 10's of kWs. The second one is the PowerPipe, an in-conduit system which can be implemented in existing or new conduits and that generates electricity from excess head pressure in rapidly flowing water transmission pipelines; the PowerPipe can be used in low head or incremental sites. With Vigor's technology it is possible to generate renewable energy economically on a small scale and to leverage under-utilized infrastructures. However, to date, few field applications have been carried out. This presentation provided information on a technology which has the potential to produce a steady supply of reliable renewable energy on a small scale.

  8. Quick and clean cloning.

    Science.gov (United States)

    Thieme, Frank; Marillonnet, Sylvestre

    2014-01-01

    Identification of unknown sequences that flank known sequences of interest requires PCR amplification of DNA fragments that contain the junction between the known and unknown flanking sequences. Since amplified products often contain a mixture of specific and nonspecific products, the quick and clean (QC) cloning procedure was developed to clone specific products only. QC cloning is a ligation-independent cloning procedure that relies on the exonuclease activity of T4 DNA polymerase to generate single-stranded extensions at the ends of the vector and insert. A specific feature of QC cloning is the use of vectors that contain a sequence called catching sequence that allows cloning specific products only. QC cloning is performed by a one-pot incubation of insert and vector in the presence of T4 DNA polymerase at room temperature for 10 min followed by direct transformation of the incubation mix in chemo-competent Escherichia coli cells.

  9. Flue gas cleaning chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gutberlet, H. [VEBA Kraftwerke Ruhr AG, Gelsenkirchen (Germany)

    1996-12-01

    The introduction of modern flue gas cleaning technology into fossil-fueled power stations has repeatedly confronted the power station chemists with new and interesting problems over the last 15 - 20 years. Both flue gas desulphurization by lime washing and catalytic removal of nitrogen oxides are based on simple basic chemical reactions. Owing to the use of readily available starting materials, the production of safe, useful end products and, last but not least, the possibility of implementing all this on an industrial scale by means of efficient process engineering, limestone desulphurization and catalytic removal of nitrogen oxides dominate the world market and, little by little, are becoming still more widespread. The origin and thus the quality of fuels and starting materials, the firing method, the mode of operation and engineering peculiarities in each plant interact in a complex manner. Simple cause/effect relationships are frequently incapable of explaining phenomena; thinking in complex interrelationships is needed. (EG)

  10. Gas-Liquid Supersonic Cleaning and Cleaning Verification Spray System

    Science.gov (United States)

    Parrish, Lewis M.

    2009-01-01

    NASA Kennedy Space Center (KSC) recently entered into a nonexclusive license agreement with Applied Cryogenic Solutions (ACS), Inc. (Galveston, TX) to commercialize its Gas-Liquid Supersonic Cleaning and Cleaning Verification Spray System technology. This technology, developed by KSC, is a critical component of processes being developed and commercialized by ACS to replace current mechanical and chemical cleaning and descaling methods used by numerous industries. Pilot trials on heat exchanger tubing components have shown that the ACS technology provides for: Superior cleaning in a much shorter period of time. Lower energy and labor requirements for cleaning and de-scaling uper.ninih. Significant reductions in waste volumes by not using water, acidic or basic solutions, organic solvents, or nonvolatile solid abrasives as components in the cleaning process. Improved energy efficiency in post-cleaning heat exchanger operations. The ACS process consists of a spray head containing supersonic converging/diverging nozzles, a source of liquid gas; a novel, proprietary pumping system that permits pumping liquid nitrogen, liquid air, or supercritical carbon dioxide to pressures in the range of 20,000 to 60,000 psi; and various hoses, fittings, valves, and gauges. The size and number of nozzles can be varied so the system can be built in configurations ranging from small hand-held spray heads to large multinozzle cleaners. The system also can be used to verify if a part has been adequately cleaned.

  11. Assessing characteristic time and space scales of in-sewer processes by analysis of one year of continuous in-sewer monitoring data.

    Science.gov (United States)

    Schilperoort, R P S; Dirksen, J; Langeveld, J G; Clemens, F H L R

    2012-01-01

    Long-term and high-frequency in-sewer monitoring opens up a broad range of possibilities to study (influences on) water quantity and quality variations. Using data from the Eindhoven wastewater system in The Netherlands both dry weather flow and wet weather flow situations have been studied. For approximately 160 dry weather days mean diurnal variations of flow and pollutant concentrations have been derived. For wet weather situations (≈ 40 storm events) peak load factors have been studied. Generally, peak load factors for all considered pollutant parameters are larger than one. Peak load factors for particulate matter are larger than for dissolved constituents. Also, the smallest catchment area consistently shows the largest mean peak factors and vice versa.

  12. Following a drop of water from the cloud, throughout the sewer system, into the receiving water - Model predictive control of integrated sewer-wastewater treatment systems

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Vezzaro, Luca; Sharma, Anitha Kumari

    of pollutants discharged from treatment plants, etc.). The tools developed in the SWI project include (but are not limited to (i) rainfall nowcasting based on radar measurements, (ii) probabilistic flow forecasting based on data assimilation and stochastic models, (iii) prediction and optimization of wet...... measurements, flow and water levels, operational parameters at treatment plants) it is possible to dynamically optimize the integrated storm- and wastewater systems according to different criteria (e.g. utilizing the system fully at all times and reducing volumes of combined sewer overflows, loads......-weather performance of wastewater treatment plants, and (iv) integrated control of the different elements of the integrated wastewater systems. Full-scale testing of these tools in different catchment located in Denmark ensure that the developed tools can represent an important step forwards for on-line operation...

  13. Dopant-assisted negative photoionization Ion mobility spectrometry coupled with on-line cooling inlet for real-time monitoring H2S concentration in sewer gas.

    Science.gov (United States)

    Peng, Liying; Jiang, Dandan; Wang, Zhenxin; Hua, Lei; Li, Haiyang

    2016-06-01

    Malodorous hydrogen sulfide (H2S) gas often exists in the sewer system and associates with the problems of releasing the dangerous odor to the atmosphere and causing sewer pipe to be corroded. A simple method is in demand for real-time measuring H2S level in the sewer gas. In this paper, an innovated method based on dopant-assisted negative photoionization ion mobility spectrometry (DANP-IMS) with on-line semiconductor cooling inlet was put forward and successfully applied for the real-time measurement of H2S in sewer gas. The influence of moisture was effectively reduced via an on-line cooling method and a non-equilibrium dilution with drift gas. The limits of quantitation for the H2S in ≥60% relative humidity air could be obtained at ≤79.0ng L(-1) with linear ranges of 129-2064ng L(-1). The H2S concentration in a sewer manhole was successfully determined while its product ions were identified by an ion-mobility time-of-fight mass spectrometry. Finally, the correlation between sewer H2S concentration and the daily routines and habits of residents was investigated through hourly or real-time monitoring the variation of sewer H2S in manholes, indicating the power of this DANP-IMS method in assessing the H2S concentration in sewer system. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Percutaneous mitral valve repair.

    Science.gov (United States)

    Gillinov, A Marc; Liddicoat, John R

    2006-01-01

    Surgical mitral valve repair is the procedure of choice to treat mitral regurgitation of all etiologies. Whereas annuloplasty is the cornerstone of mitral valve repair, a variety of other surgical techniques are utilized to correct dysfunction of the leaflets and subvalvular apparatus; in most cases, surgical repair entails application of multiple repair techniques in each patient. Preclinical studies and early human experience have demonstrated that some of these surgical repair techniques can be performed using percutaneous approaches. Specifically, there has been great progress in the development of novel technology to facilitate percutaneous annuloplasty and percutaneous edge-to-edge repair. The objectives of this report were to (1) discuss the surgical foundations for these percutaneous approaches; (2) review device design and experimental and clinical results of percutaneous valve repair; and (3) address future directions, including the key challenges of patient selection and clinical trial design.

  15. A generic methodology for the optimisation of sewer systems using stochastic programming and self-optimizing control

    DEFF Research Database (Denmark)

    Maurico-Iglesias, Miguel; Castro, Ignacio Montero; Mollerup, Ane Loft

    2015-01-01

    The design of sewer system control is a complex task given the large size of the sewer networks, the transient dynamics of the water flow and the stochastic nature of rainfall. This contribution presents a generic methodology for the design of a self-optimising controller in sewer systems....... Such controller is aimed at keeping the system close to the optimal performance, thanks to an optimal selection of controlled variables. The definition of an optimal performance was carried out by a two-stage optimisation (stochastic and deterministic) to take into account both the overflow during the current...... rain event as well as the expected overflow given the probability of a future rain event. The methodology is successfully applied to design an optimising control strategy for a subcatchment area in Copenhagen. The results are promising and expected to contribute to the advance of the operation...

  16. Sewer epidemiology mass balances for assessing the illicit use of methamphetamine, amphetamine and tetrahydrocannabinol.

    Science.gov (United States)

    Khan, Usman; Nicell, Jim A

    2012-04-01

    In sewer epidemiology, mass balances are used to back-extrapolate measurements of wastewater influent concentrations of appropriate drug residues to assess the parent illicit drug's level of use in upstream populations. This study focussed on developing and refining mass balances for the use of illicit methamphetamine, amphetamine and tetrahydrocannabinol. As a first step, a multi-criteria evaluation was used to select unchanged methamphetamine, unchanged amphetamine and 11-nor-9-carboxy-tetrahydrocannabinol as the most appropriate drug residues to track a selected population's use of illicit methamphetamine, amphetamine and tetrahydrocannabinol, respectively. For each of these selected drug residues, mass balances were developed by utilizing all disposition data available for their release from all their respective sources, incorporating route-of-administration considerations where relevant, and accounting for variations in the metabolic capacity of users of the various relevant licit and illicit sources. Further, since the selected drug residues for the use of methamphetamine and amphetamine cannot only result from their use but numerous other licit and illicit sources, comprehensive general source models were developed for their enantiomeric-specific release to sewers. The relative importance of the sources identified in the general source model was evaluated by performing national substance flow analyses for a number of countries. Results suggested that licit sources of methamphetamine are expected to be only of significance in populations where its illicit use is minor. Similarly, in populations where the use of illicitly produced amphetamine is currently of relevance, licit contributions to the sewer loads of amphetamine are likely to be of negligible importance. Lastly, the study of tetrahydrocannabinol back-extrapolation mass balances suggested that further research is required to assess the importance of fecal elimination of 11-nor-9-carboxy

  17. Programmed Cleaning and Environmental Sanitation.

    Science.gov (United States)

    Gardner, John C., Ed.

    Maintenance of sanitation in buildings, plants, offices, and institutions; the selection of cleaning materials for these purposes; and the organization and supervision of the cleaning program are becoming increasingly complex and needful of a higher cost of handling. This book describes these problems and gives helpful information and guidance for…

  18. Laboratory and field investigation of chemical disinfection of combined sewer overflow in Copenhagen area

    DEFF Research Database (Denmark)

    Chhetri, Ravi Kumar; Thornberg, Dines; Berner, Jesper

    We investigated the possibility to apply performic acid (PFA) and peracetic acid (PAA) for disinfection of combined sewer overflow (CSO) in existing CSO management infrastructures. The disinfection power of PFA and PAA to Escherichia coli (E. coli) and enterococcus were studied in batch scale...... and pre-field experiment. There were no toxicological effect measured by Vibrio fischeri when CSO was disinfected with PFA, slight toxicological effect was observed on CSO disinfected with PAA. When the design for PFA based disinfection was applied to CSO collected from an authentic event. Disinfection...

  19. Kinetics of aerobic oxidation of volatile sulfur compounds in wastewater and biofilm from sewers

    DEFF Research Database (Denmark)

    Rudelle, Elise Alice; Vollertsen, Jes; Hvitved-Jacobsen, Thorkild;

    2013-01-01

    ) and total inorganic sulfide, which have all been reported as main constituents of foul sewer gas. Samples of wastewater and biofilm for the experiments were obtained from two locations that differed significantly with respect to occurrence of VSCs. One location represented an odor hot-spot downstream......: total inorganic sulfide > EtSH > MeSH >> DMS. Except for total inorganic sulfide oxidation in wastewater, kinetic parameters for each VSC were of similar magnitude for the two locations. In the wastewater from the odor hot-spot, sulfide oxidation rates were approximately 12 times faster than...

  20. Graph theoretical stable allocation as a tool for central control of sewer systems

    Science.gov (United States)

    van Nooijen, Ronald; Kolechkina, Alla

    2016-04-01

    Dutch sewer networks consist of multiple sub-networks that serve both to collect waste water and as a link in the transport chain of waste water to the Waste Water Treatment Plant. Within sub-networks transport is by gravity driven flow. The sub-networks are linked by pumping stations. If the network of pipes also serves to collect precipitation then the system is called a combined system. For some of these networks it may be beneficial to implement central control. We study whether the graph theoretical concept of stable allocations can be used as a basis for the algorithm underlying such a central conrol system.

  1. Prioritising sewerage maintenance using inferred sewer age: a case study for Edinburgh.

    Science.gov (United States)

    Arthur, S; Burkhard, R

    2010-01-01

    The reported research project focuses on using a database which contains details of customer contacts and CCTV data for a key Scottish catchment to construct a GIS based sewer condition model. Given the nature of the asset registry, a key research challenge was estimating the age of individual lengths of pipe. Within this context, asset age was inferred using the estimated age of surface developments-this involved overlaying the network in a GIS with historical digital maps. The paper illustrates that inferred asset age can reliably be used to highlight assets which are more likely to fail.

  2. Monitoring and analysis of combined sewer overflows, Riverside and Evanston, Illinois, 1997-99

    Science.gov (United States)

    Waite, Andrew M.; Hornewer, Nancy J.; Johnson, Gary P.

    2002-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, collected and analyzed flow data in combined sewer systems in Riverside and Evanston, northeastern Illinois, from March 1997 to December 1999. Continuous 2- and 5-minute stage and velocity data were collected during surcharged and nonsurcharged conditions at 12 locations. Mass balances were calculated to determine the volume of water flowing through the tide-gate openings to the Des Plaines River and the North Shore Channel and to determine the volume of water flowing past the sluice gate to the deep tunnel. The sewer systems consist of circular pipes ranging in diameter from 0.83 feet to 10.0 feet, elliptical siphon pipes, ledges, and tide and sluice gates. Pipes were constructed of either brick and mortar or concrete, and ranged from having smooth surfaces to rough, pitted and crumbling surfaces. One pipe was noticeably affected by water infiltration from saturated ground. During data analysis, many assumptions were necessary because of the complexity of the flow data and sewer-system configurations. These assumptions included estimating the volume of water entering an interceptor sewer at the ''Gage Street pipe'' at Riverside, the effect of infiltration on the ''brick pipe'' at Riverside, and the minimum velocity required for the meter to make an accurate velocity determination. Other factors affecting the analysis of flow data included possible non-instrumented sources of inflow, and backwater conditions in some pipes, which could have caused error in the data analysis. Variations of these assumptions potentially could cause appreciable changes to the final massbalance calculations. Mass-balance analysis at Riverside indicated a total inflow volume into chamber 3 of approximately 721,000 cubic feet (ft3) during April 22-26, 1999. Outflow volume to the Des Plaines River at Riverside through the tide gate was approximately 132,000 ft3; outflow volume to the deep tunnel through the

  3. Probabilistic modelling of combined sewer overflow using the First Order Reliability Method

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Schaarup-Jensen, Kjeld; Jensen, Jacob Birk

    2007-01-01

    This paper presents a new and alternative method (in the context of urban drainage) for probabilistic hydrodynamical analysis of drainage systems in general and especially prediction of combined sewer overflow. Using a probabilistic shell it is possible to implement both input and parameter...... uncertainties on an application of the commercial urban drainage model MOUSE combined with the probabilistic First Order Reliability Method (FORM). Applying statistical characteristics on several years of rainfall, it is possible to derive a parameterization of the rainfall input and the failure probability...

  4. Probabilistic Modelling of Combined Sewer Overflow Using the First Order Reliability Method

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Schaarup-Jensen, Kjeld; Jensen, Jacob Birk

    2008-01-01

    This paper presents a new and alternative method (in the context of urban drainage) for probabilistic hydrodynamical analysis of drainage systems in general and especially prediction of combined sewer overflow. Using a probabilistic shell it is possible to implement both input and parameter...... uncertainties on an application of the commercial urban drainage model MOUSE combined with the probabilistic First Order Reliability Method (FORM). Applying statistical characteristics on several years of rainfall, it is possible to derive a parameterization of the rainfall input and the failure probability...

  5. Uncovering the secret lives of sewer rats (Rattus norvegicus): Movements, distribution and population dynamics revealed by a capture-mark-recapture study

    DEFF Research Database (Denmark)

    Heiberg, Ann-Charlotte; Sluydts, Vincent; Leirs, Herwig E.l.

    2012-01-01

    , half of these were juveniles. The median time an individual was present in the sewers was 4 months with maxima up to 22 months. Abundance ranged from 2 to 44 animals per sewer system and the dynamics showed no regular fluctuations. Rats were distributed throughout the study area, regardless of sewer...... dimensions. Juvenile rats were captured more in the smaller and drier sewer sections. Activity areas of rats of both sexes overlapped partially, and observations of bite wounds were rare, suggesting a high degree of tolerance. The average maximal distance covered by rats was ~200 m for both sexes. Day...... a surface area of 30 Ha. Multiple-capture live traps were placed in manholes in public sewers; animals were marked individually and data were collected every fourth week for a period of almost 3 years. Key results.: In total, 332 individual rats were trapped. Approximately one-third were only caught once...

  6. A Note on Clean Rings

    Institute of Scientific and Technical Information of China (English)

    Zhou Wang; Jianlong Chen

    2007-01-01

    Let R be a ring and g(x) a polynomial in C[x],where C=C(R) denotes the center of R.Camillo and Sim6n called the ring g(x)-clean if every element of R can be written as the sum of a unit and a root of g(x).In this paper,we prove that for a,b (E) C,the ring R is clean and b - a is invertible in R if and only if R is g1(x)-clean,where gl(x) = (x - a)(x - b).This implies that in some sense the notion of g(x)-clean rings in the Nicholson-Zhou Theorem and in the Camillo-Sim6n Theorem is indeed equivalent to the notion of clean rings.

  7. Air Cleaning Technologies

    Science.gov (United States)

    2005-01-01

    Executive Summary Objective This health technology policy assessment will answer the following questions: When should in-room air cleaners be used? How effective are in-room air cleaners? Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone? What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan? The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario’s capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry’s Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Clinical Need Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering

  8. Sewerage Pumping Stations, File name = UTILITIES - PARTIAL Data is incomplete. Contains electric trans lines, electric substations, sewer plants, sewer pumpstations, water plants, water tanks http://www.harfordcountymd.gov/gis/Index.cfm, Published in 2011, 1:600 (1in=50ft) scale, Harford County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Sewerage Pumping Stations dataset current as of 2011. File name = UTILITIES - PARTIAL Data is incomplete. Contains electric trans lines, electric substations, sewer...

  9. Sewerage Treatment Plants, File name = UTILITIES - PARTIAL Data is incomplete. Contains electric trans lines, electric substations, sewer plants, sewer pumpstations, water plants, water tanks http://www.harfordcountymd.gov/gis/Index.cfm, Published in 2011, 1:600 (1in=50ft) scale, Harford County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Sewerage Treatment Plants dataset current as of 2011. File name = UTILITIES - PARTIAL Data is incomplete. Contains electric trans lines, electric substations, sewer...

  10. Remaining Sites Verification Package for the 1607-F3 Sanitary Sewer System, Waste Site Reclassification Form 2006-047

    Energy Technology Data Exchange (ETDEWEB)

    L. M. Dittmer

    2007-04-26

    The 1607-F3 waste site is the former location of the sanitary sewer system that supported the 182-F Pump Station, the 183-F Water Treatment Plant, and the 151-F Substation. The sanitary sewer system included a septic tank, drain field, and associated pipeline, all in use between 1944 and 1965. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.

  11. Succession of Sulfur-Oxidizing Bacteria in the Microbial Community on Corroding Concrete in Sewer Systems† ▿

    OpenAIRE

    Okabe, Satoshi; Odagiri, Mitsunori; Ito, Tsukasa; Satoh, Hisashi

    2007-01-01

    Microbially induced concrete corrosion (MICC) in sewer systems has been a serious problem for a long time. A better understanding of the succession of microbial community members responsible for the production of sulfuric acid is essential for the efficient control of MICC. In this study, the succession of sulfur-oxidizing bacteria (SOB) in the bacterial community on corroding concrete in a sewer system in situ was investigated over 1 year by culture-independent 16S rRNA gene-based molecular ...

  12. Clean Metal Casting

    Energy Technology Data Exchange (ETDEWEB)

    Makhlouf M. Makhlouf; Diran Apelian

    2002-02-05

    The objective of this project is to develop a technology for clean metal processing that is capable of consistently providing a metal cleanliness level that is fit for a given application. The program has five tasks: Development of melt cleanliness assessment technology, development of melt contamination avoidance technology, development of high temperature phase separation technology, establishment of a correlation between the level of melt cleanliness and as cast mechanical properties, and transfer of technology to the industrial sector. Within the context of the first task, WPI has developed a standardized Reduced Pressure Test that has been endorsed by AFS as a recommended practice. In addition, within the context of task1, WPI has developed a melt cleanliness sensor based on the principles of electromagnetic separation. An industrial partner is commercializing the sensor. Within the context of the second task, WPI has developed environmentally friendly fluxes that do not contain fluorine. Within the context of the third task, WPI modeled the process of rotary degassing and verified the model predictions with experimental data. This model may be used to optimize the performance of industrial rotary degassers. Within the context of the fourth task, WPI has correlated the level of melt cleanliness at various foundries, including a sand casting foundry, a permanent mold casting foundry, and a die casting foundry, to the casting process and the resultant mechanical properties. This is useful in tailoring the melt cleansing operations at foundries to the particular casting process and the desired properties of cast components.

  13. Clean tracks for ATLAS

    CERN Multimedia

    2006-01-01

    First cosmic ray tracks in the integrated ATLAS barrel SCT and TRT tracking detectors. A snap-shot of a cosmic ray event seen in the different layers of both the SCT and TRT detectors. The ATLAS Inner Detector Integration Team celebrated a major success recently, when clean tracks of cosmic rays were detected in the completed semiconductor tracker (SCT) and transition radiation tracker (TRT) barrels. These tracking tests come just months after the successful insertion of the SCT into the TRT (See Bulletin 09/2006). The cosmic ray test is important for the experiment because, after 15 years of hard work, it is the last test performed on the fully assembled barrel before lowering it into the ATLAS cavern. The two trackers work together to provide millions of channels so that particles' tracks can be identified and measured with great accuracy. According to the team, the preliminary results were very encouraging. After first checks of noise levels in the final detectors, a critical goal was to study their re...

  14. 77 FR 24515 - Notice of Lodging of Consent Decree Pursuant to the Clean Water Act

    Science.gov (United States)

    2012-04-24

    ... sewer management, operation and maintenance programs, including: A sewer overflow response plan, a fats... States. Tennessee's payment will be in the form of state projects including an effluent study at the...

  15. Precision Cleaning - Path to Premier

    Science.gov (United States)

    Mackler, Scott E.

    2008-01-01

    ITT Space Systems Division s new Precision Cleaning facility provides critical cleaning and packaging of aerospace flight hardware and optical payloads to meet customer performance requirements. The Precision Cleaning Path to Premier Project was a 2007 capital project and is a key element in the approved Premier Resource Management - Integrated Supply Chain Footprint Optimization Project. Formerly precision cleaning was located offsite in a leased building. A new facility equipped with modern precision cleaning equipment including advanced process analytical technology and improved capabilities was designed and built after outsourcing solutions were investigated and found lacking in ability to meet quality specifications and schedule needs. SSD cleans parts that can range in size from a single threaded fastener all the way up to large composite structures. Materials that can be processed include optics, composites, metals and various high performance coatings. We are required to provide verification to our customers that we have met their particulate and molecular cleanliness requirements and we have that analytical capability in this new facility. The new facility footprint is approximately half the size of the former leased operation and provides double the amount of throughput. Process improvements and new cleaning equipment are projected to increase 1st pass yield from 78% to 98% avoiding $300K+/yr in rework costs. Cost avoidance of $350K/yr will result from elimination of rent, IT services, transportation, and decreased utility costs. Savings due to reduced staff expected to net $4-500K/yr.

  16. Optimality in DNA repair.

    Science.gov (United States)

    Richard, Morgiane; Fryett, Matthew; Miller, Samantha; Booth, Ian; Grebogi, Celso; Moura, Alessandro

    2012-01-07

    DNA within cells is subject to damage from various sources. Organisms have evolved a number of mechanisms to repair DNA damage. The activity of repair enzymes carries its own risk, however, because the repair of two nearby lesions may lead to the breakup of DNA and result in cell death. We propose a mathematical theory of the damage and repair process in the important scenario where lesions are caused in bursts. We use this model to show that there is an optimum level of repair enzymes within cells which optimises the cell's response to damage. This optimal level is explained as the best trade-off between fast repair and a low probability of causing double-stranded breaks. We derive our results analytically and test them using stochastic simulations, and compare our predictions with current biological knowledge.

  17. Dynamics of pollutant discharge in combined sewer systems during rain events: chance or determinism?

    Science.gov (United States)

    Hannouche, A; Chebbo, G; Joannis, C

    2014-01-01

    A large database of continuous flow and turbidity measurements cumulating data on hundreds of rain events and dry weather days from two sites in Paris (called Quais and Clichy) and one in Lyon (called Ecully) is presented. This database is used to characterize and compare the behaviour of the three sites at the inter-events scale. The analysis is probed through three various variables: total volumes and total suspended solids (TSS) masses and concentrations during both wet and dry weather periods in addition to the contributions of diverse-origin sources to event flow volume and TSS load values. The results obtained confirm the previous findings regarding the spatial consistency of TSS fluxes and concentrations between both sites in Paris having similar land uses. Moreover, masses and concentrations are proven to be correlated between Parisian sites in a way that implies the possibility of some deterministic processes being reproducible from one catchment to another for a particular rain event. The results also demonstrate the importance of the contribution of wastewater and sewer deposits to the total events' loads and show that such contributions are not specific to Paris sewer networks.

  18. Innovative framework to simulate the fate and transport of nonconservative constituents in urban combined sewer catchments

    Science.gov (United States)

    Morales, V. M.; Quijano, J. C.; Schmidt, A.; Garcia, M. H.

    2016-11-01

    We have developed a probabilistic model to simulate the fate and transport of nonconservative constituents in urban watersheds. The approach implemented here extends previous studies that rely on the geomorphological instantaneous unit hydrograph concept to include nonconservative constituents. This is implemented with a factor χ that affects the transfer functions and therefore accounts for the loss (gain) of mass associated with the constituent as it travels through the watershed. Using this framework, we developed an analytical solution for the dynamics of dissolved oxygen (DO) and biochemical oxygen demand (BOD) in urban networks based on the Streeter and Phelps model. This model breaks down the catchment into a discreet number of possible flow paths through the system, requiring less data and implementation effort than well-established deterministic models. Application of the model to one sewer catchment in the Chicago area with available BOD information proved its ability to predict the BOD concentration observed in the measurements. In addition, comparison of the model with a calibrated Storm Water Management Model (SWMM) of another sewer catchment from the Chicago area showed that the model predicted the BOD concentration as well as the widely accepted SWMM. The developed model proved to be a suitable alternative to simulate the fate and transport of constituents in urban catchments with limited and uncertain input data.

  19. Particle velocity and sediment transport at the limit of deposition in sewers.

    Science.gov (United States)

    Ota, J J; Perrusquía, G S

    2013-01-01

    This paper focuses on the sediment particle while it is transported at the limit of deposition in storm sewers, i.e. as bed load at the limit of concentration that leads to sediment deposition. Although many empirical sediment transport equations are known in the literature, there is only limited knowledge concerning particle velocity. Sediment particle and sphere velocity measurements were carried out in two pipe channels and these results led to the development of a semi-theoretical equation for sediment transport at the limit of deposition in sewers. Even in the transport process without deposition, sediment movement is slower than water velocity and depends on the angle of repose of sediment with a diameter d on the roughness k of the pipe channel. Instead of classical dimensionless bed shear stress ψ, a modified dimensionless bed shear stress ψ (d/k)(2/3) was suggested, based on the angle of repose and this parameter was proved to be significant for quantifying the transport capacity. The main purpose of this article is to emphasize the importance of careful observation of experiments. Not only number of tests, but physical understanding are essential for better empirical equations.

  20. A multi-objective optimisation model for sewer rehabilitation considering critical risk of failure.

    Science.gov (United States)

    Ward, Ben; Savić, Dragan A

    2012-01-01

    A unique methodology for the optimal specification of sewer rehabilitation investment is presented in this paper. By accounting for the critical risk of asset failure, this methodology builds on previously successful work which explored the application of multi-objective optimisation tools to assist engineers with the specification of optimal rehabilitation strategies. The conventional sewerage rehabilitation specification process relies on the expertise of professional engineers to manually evaluate CCTV inspection information when determining the nature and extent of the rehabilitation solution. This process is not only tedious and subjective but it has no quantifiable means of identifying optimal solutions or possible combinations of optimal solutions in the delivery of catchment wide rehabilitation programmes. Therefore, the purely manual process of sewer rehabilitation design leaves a number of unanswered questions, such as: (1) Does the solution offer the greatest structural benefit to the network? (2) Is the solution the most cost-effective solution available? (3) Does the solution most greatly reduce the risk of critical asset failure? The application of a multi-objective genetic algorithm optimisation model, coupled with an enhanced critical risk methodology, has successfully answered these questions when applied to a case study data set provided by South West Water (UK).

  1. Growth kinetics of hydrogen sulfide oxidizing bacteria in corroded concrete from sewers.

    Science.gov (United States)

    Jensen, Henriette Stokbro; Lens, Piet N L; Nielsen, Jeppe L; Bester, Kai; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes

    2011-05-30

    Hydrogen sulfide oxidation by microbes present on concrete surfaces of sewer pipes is a key process in sewer corrosion. The growth of aerobic sulfur oxidizing bacteria from corroded concrete surfaces was studied in a batch reactor. Samples of corrosion products, containing sulfur oxidizing bacteria, were suspended in aqueous solution at pH similar to that of corroded concrete. Hydrogen sulfide was supplied to the reactor to provide the source of reduced sulfur. The removal of hydrogen sulfide and oxygen was monitored. The utilization rates of both hydrogen sulfide and oxygen suggested exponential bacterial growth with median growth rates of 1.25 d(-1) and 1.33 d(-1) as determined from the utilization rates of hydrogen sulfide and oxygen, respectively. Elemental sulfur was found to be the immediate product of the hydrogen sulfide oxidation. When exponential growth had been achieved, the addition of hydrogen sulfide was terminated leading to elemental sulfur oxidation. The ratio of consumed sulfur to consumed oxygen suggested that sulfuric acid was the ultimate oxidation product. To the knowledge of the authors, this is the first study to determine the growth rate of bacteria involved in concrete corrosion with hydrogen sulfide as source of reduced sulfur.

  2. Growth kinetics of hydrogen sulfide oxidizing bacteria in corroded concrete from sewers

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Henriette Stokbro, E-mail: h.s.jensen@sheffield.ac.uk [Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg (Denmark); Lens, Piet N.L. [Sub-department of Environmental Technology, Agricultural University of Wageningen, Bomenweg 2, NL-6700-EV Wageningen (Netherlands); Nielsen, Jeppe L.; Bester, Kai; Nielsen, Asbjorn Haaning; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes [Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg (Denmark)

    2011-05-30

    Hydrogen sulfide oxidation by microbes present on concrete surfaces of sewer pipes is a key process in sewer corrosion. The growth of aerobic sulfur oxidizing bacteria from corroded concrete surfaces was studied in a batch reactor. Samples of corrosion products, containing sulfur oxidizing bacteria, were suspended in aqueous solution at pH similar to that of corroded concrete. Hydrogen sulfide was supplied to the reactor to provide the source of reduced sulfur. The removal of hydrogen sulfide and oxygen was monitored. The utilization rates of both hydrogen sulfide and oxygen suggested exponential bacterial growth with median growth rates of 1.25 d{sup -1} and 1.33 d{sup -1} as determined from the utilization rates of hydrogen sulfide and oxygen, respectively. Elemental sulfur was found to be the immediate product of the hydrogen sulfide oxidation. When exponential growth had been achieved, the addition of hydrogen sulfide was terminated leading to elemental sulfur oxidation. The ratio of consumed sulfur to consumed oxygen suggested that sulfuric acid was the ultimate oxidation product. To the knowledge of the authors, this is the first study to determine the growth rate of bacteria involved in concrete corrosion with hydrogen sulfide as source of reduced sulfur.

  3. Coupled 1D-2D hydrodynamic inundation model for sewer overflow: Influence of modeling parameters

    Directory of Open Access Journals (Sweden)

    Adeniyi Ganiyu Adeogun

    2015-10-01

    Full Text Available This paper presents outcome of our investigation on the influence of modeling parameters on 1D-2D hydrodynamic inundation model for sewer overflow, developed through coupling of an existing 1D sewer network model (SWMM and 2D inundation model (BREZO. The 1D-2D hydrodynamic model was developed for the purpose of examining flood incidence due to surcharged water on overland surface. The investigation was carried out by performing sensitivity analysis on the developed model. For the sensitivity analysis, modeling parameters, such as mesh resolution Digital Elevation Model (DEM resolution and roughness were considered. The outcome of the study shows the model is sensitive to changes in these parameters. The performance of the model is significantly influenced, by the Manning's friction value, the DEM resolution and the area of the triangular mesh. Also, changes in the aforementioned modeling parameters influence the Flood characteristics, such as the inundation extent, the flow depth and the velocity across the model domain.

  4. Combined sewer overflow control with LID based on SWMM: an example in Shanghai, China.

    Science.gov (United States)

    Liao, Z L; Zhang, G Q; Wu, Z H; He, Y; Chen, H

    2015-01-01

    Although low impact development (LID) has been commonly applied across the developed countries for mitigating the negative impacts of combined sewer overflows (CSOs) on urban hydrological environment, it has not been widely used in developing countries yet. In this paper, a typical combined sewer system in an urbanized area of Shanghai, China was used to demonstrate how to design and choose CSO control solutions with LID using stormwater management model. We constructed and simulated three types of CSO control scenarios. Our findings support the notion that LID measures possess favorable capability on CSO reduction. Nevertheless, the green scenarios which are completely comprised by LID measures fail to achieve the maximal effectiveness on CSO reduction, while the gray-green scenarios (LID measure combined with gray measures) achieve it. The unit cost-effectiveness of each type of scenario sorts as: green scenario > gray-green scenario > gray scenario. Actually, as the storage tank is built in the case catchment, a complete application of green scenario is inaccessible here. Through comprehensive evaluation and comparison, the gray-green scenario F which used the combination of storage tank, bio-retention and rain barrels is considered as the most feasible one in this case.

  5. Contribution of combined sewer overflows to trace contaminant loads in urban streams.

    Science.gov (United States)

    Weyrauch, Philip; Matzinger, Andreas; Pawlowsky-Reusing, Erika; Plume, Stephan; von Seggern, Dörthe; Heinzmann, Bernd; Schroeder, Kai; Rouault, Pascale

    2010-08-01

    The present study examines the contribution of combined sewer overflows (CSO) to loads and concentrations of trace contaminants in receiving surface water. A simple method to assess the ratio of CSO to wastewater treatment plant (WWTP) effluents was applied to the urban River Spree in Berlin, Germany. The assessment indicated that annual loads are dominated by CSO for substances with removal in WWTP above approximately 95%. Moreover, it showed that substances with high removal in WWTP can lead to concentration peaks in the river during CSO events. The calculated results could be verified based on eight years of monitoring data from the River Spree, collected between 2000 and 2007. Substances that are well removed in WWTP such as NTA (nitrilotriacetic acid) were found to occur in significantly increased concentration during CSO, while the concentration of substances that are poorly removable in WWTP such as EDTA (ethylenediaminetetraacetic acid) decreased in CSO-influenced samples due to dilution effects. The overall results indicate the potential importance of the CSO pathway of well-removable sewage-based trace contaminants to rivers. In particular, high concentrations during CSO events may be relevant for aquatic organisms. Given the results, it is suggested to include well-removable, sewage-based trace contaminants, a substance group often neglected in the past, in future studies on urban rivers in case of combined sewer systems. The presented methodology is suggested for a first assessment, since it is based solely on urban drainage data, which is available in most cities.

  6. Predicting combined sewer overflows chamber depth using artificial neural networks with rainfall radar data.

    Science.gov (United States)

    Mounce, S R; Shepherd, W; Sailor, G; Shucksmith, J; Saul, A J

    2014-01-01

    Combined sewer overflows (CSOs) represent a common feature in combined urban drainage systems and are used to discharge excess water to the environment during heavy storms. To better understand the performance of CSOs, the UK water industry has installed a large number of monitoring systems that provide data for these assets. This paper presents research into the prediction of the hydraulic performance of CSOs using artificial neural networks (ANN) as an alternative to hydraulic models. Previous work has explored using an ANN model for the prediction of chamber depth using time series for depth and rain gauge data. Rainfall intensity data that can be provided by rainfall radar devices can be used to improve on this approach. Results are presented using real data from a CSO for a catchment in the North of England, UK. An ANN model trained with the pseudo-inverse rule was shown to be capable of predicting CSO depth with less than 5% error for predictions more than 1 hour ahead for unseen data. Such predictive approaches are important to the future management of combined sewer systems.

  7. Toxicity and pollutant impact analysis in an urban river due to combined sewer overflows loads.

    Science.gov (United States)

    Casadio, A; Maglionico, M; Bolognesi, A; Artina, S

    2010-01-01

    The Navile Channel (Bologna, Italy) is an ancient artificial water course derived from the Reno river. It is the main receiving water body for the urban catchment of Bologna sewer systems and also for the Waste Water Treatment Plant (WWTP) main outlet. The aim of this work is to evaluate the Combined Sewer Overflows (CSOs) impact on Navile Channel's water quality. In order to collect Navile flow and water quality data in both dry and wet weather conditions, two measuring and sampling stations were installed, right upstream and downstream the WWTP outflow. The study shows that even in case of low intensity rain events, CSOs have a significant effect on both water quantity and quality, spilling a considerable amount of pollutants into the Navile Channel and presenting also acute toxicity effects. The collected data shown a good correlations between the concentrations of TSS and of chemical compounds analyzed, suggesting that the most part of such substances is attached to suspended solids. Resulting toxicity values are fairly high in both measuring points and seem to confirm synergistic interactions between heavy metals.

  8. CLEAN Technique for Polarimetric ISAR

    Directory of Open Access Journals (Sweden)

    M. Martorella

    2008-01-01

    Full Text Available Inverse synthetic aperture radar (ISAR images are often used for classifying and recognising targets. To reduce the amount of data processed by the classifier, scattering centres are extracted from the ISAR image and used for classifying and recognising targets. This paper addresses the problem of estimating the position and the scattering vector of target scattering centres from polarimetric ISAR images. The proposed technique is obtained by extending the CLEAN technique, which was introduced in radar imaging for extracting scattering centres from single-polarisation ISAR images. The effectiveness of the proposed algorithm, namely, the Polarimetric CLEAN (Pol-CLEAN is tested on simulated and real data.

  9. A REVIEW ON CONCEPT OF CLEANING VALIDATION IN PHARMACEUTICAL INDUSTRY

    National Research Council Canada - National Science Library

    Shashikant; Prashar Bharat; Kumar Satinder

    2012-01-01

    .... This article provide introduction on cleaning validation and the associated regulations, level/degree of cleaning, approaches to cleaning validation, elements of cleaning validation, validation...

  10. An experiment to use medical I-131 as tracer in a city sewer system

    Energy Technology Data Exchange (ETDEWEB)

    Ulbrich, Susanne; Fischer, Helmut W. [University of Bremen, Institute of Environmental Physics, Otto-Hahn-Allee 1, D-28359 Bremen (Germany)

    2014-07-01

    City sewer systems have to reliably carry residential and industrial wastewater to treatment plants, often mixed with rainwater. Transport in the sewer system is regularly modelled in order to predict sewerage levels, transport velocities and volume discharges. Radioisotopes would be interesting tracers, as they can be detected quickly and without the need of applying wet chemistry. Medical isotopes are released in large quantities (many MBq) by excretion from patients either at the location of administration or from elsewhere, most probably the patient's home. Depending on diagnostic or treatment modality, isotopes of different physical characteristics are used, often bound to compounds of specific metabolic behaviour. Routine environmental surveillance regularly detects the most common diagnostic ({sup 99m}Tc) and therapeutic ({sup 131}I) isotopes in city wastewater samples. Except for {sup 131}I in the case of a nuclear emergency, no contributions from sources other than medical are expected. Medical isotopes therefore might be used for tracing purposes, provided individual inputs can be identified and separated. A field experiment has been designed involving {sup 131}I releases from a single patient who had undergone radioiodine thyroid ablation therapy. This modality is applied after thyroid cancer surgery in order to destroy residual thyroid tissue. Activities up to 5 GBq of {sup 131}I are used which are excreted within few days, as no iodine-retaining thyroid tissue remains. In Germany, about 20,000 of these treatments are performed yearly. For a sewer system of 500,000 inhabitants, about 150 cases would be expected per year, making it quite improbable to have interference between individual patient releases in the same region of the city sewer system. Practically, the radiometric laboratory was informed of the expected release of an (anonymous) patient from the collaborating radiotherapy unit several days in advance, plus the approximate location of

  11. The effects of sewer infrastructure on water quality: implications for land use studies.

    Science.gov (United States)

    Vrebos, Dirk; Staes, Jan; Meire, Patrick

    2010-05-01

    The European Water Framework Directive requires a good ecological status of the European water bodies and the necessary measures to obtain this have to be implemented. The water quality of a river is the result of complex anthropogenic systems (buildings, waste water treatment infrastructure, regulations, etc.) and biogeochemical and eco-hydrological interactions. It is therefore essential to obtain more insight in the factors that determine the water quality in a river. Research into the relation between land use and water quality is necessary. Human activities have a huge impact on the flow regimes and associated water quality of river systems. Effects of land use bound activities on water quality are often investigated, but these studies generally ignore the hydrological complexity of a human influenced catchment. Infrastructure like sewer systems and wastewater treatment plants (WWTP) can displace huge quantities of polluted water. The transfers change flow paths, displace water between catchments and change the residence time of the system. If we want to correctly understand the effect of land use distribution on water quality we have to take these sewer systems into account. In this study we analyse the relation between land use and water quality in the Nete catchment (Belgium) and investigate the impact of the sewage infrastructure on this relation. The Nete catchment (1.673 km²) is a mosaic of semi natural, agricultural and urbanized areas and the land use is very fragmented. For the moment 74% of the households within the catchment are connected to a WWTP. The discharges from these WWTP's compose 15% of the total discharge of the Nete. Based on a runoff model the surface of upstream land use was calculated for 378 points. These data were then corrected for the impact of WWTP's. Using sewage infrastructure plans, urban areas connected to a WWTP were added to the upstream land use of the WWTP's water receiving stream. In order to understand the effect of

  12. 76 FR 56223 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2011-09-12

    ... time periods, related to alleged discharges of untreated sewage from Elkhart's combined sewer collection system, i.e. ``combined sewer overflows,'' during wet weather events, and some dry weather time... would require Elkhart to reduce its combined sewer overflows by comprehensively upgrading and...

  13. 77 FR 75446 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2012-12-20

    ... address combined sewer overflows by December 1, 2037 and to pay a $340,000 civil penalty, 50% to the... District of Pennsylvania in the lawsuit entitled United States v. Sewer Authority of the City of Scranton.... Scranton Sewer Authority, D.J. Ref. No. 90-5-1-1-08778. All comments must be submitted no later than...

  14. 77 FR 809 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2012-01-06

    ... relevant time periods, related to alleged discharges of untreated sewage from South Bend's combined sewer collection system, i.e. ``combined sewer overflows,'' during wet weather events, and some dry weather time... would require South Bend to reduce its combined sewer overflows by comprehensively upgrading...

  15. 77 FR 43860 - Notice of Lodging of a Consent Decree Pursuant to the Clean Water Act

    Science.gov (United States)

    2012-07-26

    ... its entire sewer collection system to eliminate overflows of untreated raw sewage. Chattanooga will... to ensure proper management, operation and maintenance of its sewer systems; and install additional controls on the Chattanooga Creek combined sewer outfalls to ensure compliance with water quality...

  16. 76 FR 50757 - Notice of Lodging of a Consent Decree Under the Clean Water Act

    Science.gov (United States)

    2011-08-16

    ... weather overflows (``DWOs'') and reduce combined sewer overflows (``CSOs'') by March 2023 by completing sewer separation projects and upgrades at an approximate cost of $4.2 million; (2) pay the United States... of its municipal wastewater and sewer system. Under the proposed Consent Decree, Elkins is...

  17. Clean coal - a national urgency

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.M.; Sahai, R. [Indian Bureau of Mines, Nagpur (India). Technical Consultancy Division

    2000-07-01

    India is the third largest producer and consumer of coal in the world. Coal generally has a high ash content, thereby requiring that it be cleaned for proper use. Technological advances now make it possible to reduce pollution considerably, even as energy use increases. However, to reduce environmental impacts, technologies for cleaning coal before combustion need to be developed. The paper focuses on the need for clean coal production and the benefits associated with it. Although the country is rich in coal reserves, the generally inferior quality of coal will lead to its depletion if it is not used cleanly. Increasing the proportion of prepared coal from the current level of less than 5% (i.e. 10-11 million tonnes per annum) of all coal consumed will lead to a massive saving. This can be achieved if new washeries are set up, preferably near the coalfields. 2 figs.

  18. First cleaning with LHC collimators

    CERN Document Server

    Wollmann, D; Arnau-Izquiedo, G; Assmann, R; Bacher, J P; Baglin, V; Bellodi, G; Bertarelli, A; Bouzoud, A; Bracco, C; Bruce, R; Brugger, M; Calatroni, S; Cerruti, F; Chamizo, R; Cherif, A; Chiaveri, E; Chiggiato, P; Dallochio, A; Dehning, B; Donze, M; Ferrari, A; Folch, R; Francon, P; Gander, P; Geisser, J M; Grudiev, A; Holzer, EB; Jacquet, D; Jeanneret, J B; Jimenez, J M; Jonker, M; Jowett, J; Kershaw, K; Lari, L; Lendaro, J; Loprete, F; Losito, R; Magistris, M; Malabaila, M; Mayer, M; Marsili, A; Masi, A; Mathot, S; Métral, E; Mitifiot, C; Mounet, N; de Morais Amaral, R; Nordt, A; Perret, R; Perrollaz, S; Rathjen, C; Redaelli, S; Robert-Demolaize, G; Roesler, S; Rossi, A; Salvant, B; Santana, M; Sexton, I; Sievers, P; Tardy, T; Timmins, M; Tsoulou, K; Veyrunes, E; Vincke, H; Vlachoudis, V; Vuillemin, V; Weiler, T; Zimmermann, F; Baishev, I; Kurochkin, I; Kaltchev, D; Caspers, F; Kadi, Y

    2010-01-01

    The LHC has two dedicated cleaning insertions: IR3 for momentum cleaning and IR7 for betatron cleaning. The collimation system has been specified and built with tight mechanical tolerances (e.g. jaw flatness ~ 40 μm ) and is designed to achieve a high accuracy and reproducibility of the jaw positions (~ 20 μm). The practically achievable cleaning efficiency of the present Phase-I system depends on the precision of the jaw centering around the beam, the accuracy of the gap size and the jaw parallelism against the beam. The reproducibility and stability of the collimation system is important to avoid the frequent repetition of beam based alignment which is currently a lengthy procedure. Within this paper we describe the method used for the beam based alignment of the LHC collimation system, its achieved accuracy and stability and its performance at 450GeV.

  19. Ultrasonic cleaning in the hospital.

    Science.gov (United States)

    Detwiler, M S

    1989-04-01

    Ultrasonic cleaning can prolong the life of expensive instruments. In the past, many fine instruments were discarded due to stiffening hinges and box locks, or sticking plungers. Hand scrubbing and spray washing could not thoroughly clean these areas. Ultrasonic cleaners effectively remove dried and baked blood, serums and medications from these instruments. Also, hinged instruments and syringes operate more smoothly during use in surgery when cleaned using ultrasonics. In addition, the use of ultrasonics alleviates the necessity for hand scrubbing of contaminated surgical instruments and laboratory apparatus, a procedure which could lead to injury or infection. The superb cleaning powers of ultrasonic cleaners, their speed and simplicity of operation, and their ability to remove blood, tissue, bacteria and microorganisms within minutes, makes them a valuable addition to any operating room suite, central service department, or emergency room. Their cost-effectiveness is considerable for the small hospital, and compelling for the large hospital.

  20. Hansen Cleaning Solvent Research Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Environmental regulation will force current baseline  precision cleaning solvent (AK-225) to be phased out starting 2015. We plan to develop  a new...

  1. Tracking Clean Energy Progress 2013

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    Tracking Clean Energy Progress 2013 (TCEP 2013) examines progress in the development and deployment of key clean energy technologies. Each technology and sector is tracked against interim 2020 targets in the IEA Energy Technology Perspectives 2012 2°C scenario, which lays out pathways to a sustainable energy system in 2050. Stark message emerge: progress has not been fast enough; large market failures are preventing clean energy solutions from being taken up; considerable energy efficiency remains untapped; policies need to better address the energy system as a whole; and energy-related research, development and demonstration need to accelerate. Alongside these grim conclusions there is positive news. In 2012, hybrid-electric vehicle sales passed the 1 million mark. Solar photovoltaic systems were being installed at a record pace. The costs of most clean energy technologies fell more rapidly than anticipated.

  2. Efficient methods of piping cleaning

    Directory of Open Access Journals (Sweden)

    Orlov Vladimir Aleksandrovich

    2014-01-01

    Full Text Available The article contains the analysis of the efficient methods of piping cleaning of water supply and sanitation systems. Special attention is paid to the ice cleaning method, in course of which biological foil and various mineral and organic deposits are removed due to the ice crust buildup on the inner surface of water supply and drainage pipes. These impurities are responsible for the deterioration of the organoleptic properties of the transported drinking water or narrowing cross-section of drainage pipes. The co-authors emphasize that the use of ice compared to other methods of pipe cleaning has a number of advantages due to the relative simplicity and cheapness of the process, economical efficiency and lack of environmental risk. The equipment for performing ice cleaning is presented, its technological options, terms of cleansing operations, as well as the volumes of disposed pollution per unit length of the water supply and drainage pipelines. It is noted that ice cleaning requires careful planning in the process of cooking ice and in the process of its supply in the pipe. There are specific requirements to its quality. In particular, when you clean drinking water system the ice applied should be hygienically clean and meet sanitary requirements.In pilot projects, in particular, quantitative and qualitative analysis of sediments adsorbed by ice is conducted, as well as temperature and the duration of the process. The degree of pollution of the pipeline was estimated by the volume of the remote sediment on 1 km of pipeline. Cleaning pipelines using ice can be considered one of the methods of trenchless technologies, being a significant alternative to traditional methods of cleaning the pipes. The method can be applied in urban pipeline systems of drinking water supply for the diameters of 100—600 mm, and also to diversion collectors. In the world today 450 km of pipelines are subject to ice cleaning method.Ice cleaning method is simple

  3. Automatic Vacuum Flushing Technology for Combined Sewer Solids: Laboratory Testing and Proposed Improvements (WERF Report INFR7SG09)

    Science.gov (United States)

    This research study included an extensive literature review on existing sewer sediment flushing technologies. An innovative vacuum flush system previously developed by the U.S. EPA was tested under laboratory conditions. The tests revealed a strong correlation between the strengt...

  4. Evaluation of Green Alternatives for Combined Sewer Overflow Mitigation: A Proposed Economic Impact Framework and Illustration of its Application

    Science.gov (United States)

    This report develops a broad framework, or taxonomy, for identifying and organizing the socio-economic impacts of sewer infrastructure projects. It focuses on a green project in Cincinnati, Ohio that has adopted broader economic goals. The report then uses this example to illustr...

  5. Clean Energy Solutions Center (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Reategui, S.

    2012-07-01

    The Clean Energy Ministerial launched the Clean Energy Solutions Center in April, 2011 for major economy countries, led by Australia and U.S. with other CEM partners. Partnership with UN-Energy is extending scope to support all developing countries: 1. Enhance resources on policies relating to energy access, small to medium enterprises (SMEs), and financing programs; 2. Offer expert policy assistance to all countries; 3. Expand peer to peer learning, training, and deployment and policy data for developing countries.

  6. Efficient methods of piping cleaning

    OpenAIRE

    Orlov Vladimir Aleksandrovich; Nechitaeva Valentina Anatol'evna; Bogomolova Irina Olegovna; Shaykhetdinova Yuliya Aleksandrovna; Daminova Yuliya Farikhovna

    2014-01-01

    The article contains the analysis of the efficient methods of piping cleaning of water supply and sanitation systems. Special attention is paid to the ice cleaning method, in course of which biological foil and various mineral and organic deposits are removed due to the ice crust buildup on the inner surface of water supply and drainage pipes. These impurities are responsible for the deterioration of the organoleptic properties of the transported drinking water or narrowing cross-section of d...

  7. A Commercial IOTV Cleaning Study

    Science.gov (United States)

    2010-04-12

    with Spot Cleaning. Page 46 of 118 3.2.5 Water/Oil Repellency Water repellency of the Cordura® fabrics cut from the vests and from new...combined with cleaning have contributed to the deterioration of the Cordura® material on water repellency . 2) The effects of laundering alone on the spray...repellency attribute appears to be more sensitive to the vest’s prior use history and laundering than water - repellency . Many unwashed vest samples

  8. 2012 Clean Energy: Project Summaries

    OpenAIRE

    Asian Development Bank

    2013-01-01

    This report summarizes the investments in clean energy made by the operations departments of the Asian Development Bank (ADB) in 2012, condensing information from project databases and formal reports in an easy-to-reference format. This report was prepared by ADB’s Clean Energy Program which provides the cohesive agenda that encompasses and guides ADB’s lending and non-lending assistance, initiatives, and plan of action for sustainable growth in Asia and the Pacific.

  9. Repairs of composite structures

    Science.gov (United States)

    Roh, Hee Seok

    Repair on damaged composite panels was conducted. To better understand adhesively bonded repair, the study investigates the effect of design parameters on the joint strength. The design parameters include bondline length, thickness of adherend and type of adhesive. Adhesives considered in this study were tested to measure their tensile material properties. Three types of adhesively bonded joints, single strap, double strap, and single lap joint were considered under changing bondline lengths, thickness of adherend and type of adhesive. Based on lessons learned from bonded joints, a one-sided patch repair method for composite structures was conducted. The composite patch was bonded to the damaged panel by either film adhesive FM-73M or paste adhesive EA-9394 and the residual strengths of the repaired specimens were compared under varying patch sizes. A new repair method using attachments has been suggested to enhance the residual strength. Results obtained through experiments were analyzed using finite element analysis to provide a better repair design and explain the experimental results. It was observed that the residual strength of the repaired specimen was affected by patch length. Method for rapid repairs of damaged composite structures was investigated. The damage was represented by a circular hole in a composite laminated plate. Pre-cured composite patches were bonded with a quick-curing commercial adhesive near (rather than over) the hole. Tensile tests were conducted on specimens repaired with various patch geometries. The test results showed that, among the methods investigated, the best repair method restored over 90% of the original strength of an undamaged panel. The interfacial stresses in the adhesive zone for different patches were calculated in order to understand the efficiencies of the designs of these patch repairs. It was found that the composite patch that yielded the best strength had the lowest interfacial peel stress between the patch and

  10. Clean Energy Application Center

    Energy Technology Data Exchange (ETDEWEB)

    Freihaut, Jim

    2013-09-30

    The Mid Atlantic Clean Energy Application Center (MACEAC), managed by The Penn State College of Engineering, serves the six states in the Mid-Atlantic region (Pennsylvania, New Jersey, Delaware, Maryland, Virginia and West Virginia) plus the District of Columbia. The goals of the Mid-Atlantic CEAC are to promote the adoption of Combined Heat and Power (CHP), Waste Heat Recovery (WHR) and District Energy Systems (DES) in the Mid Atlantic area through education and technical support to more than 1,200 regional industry and government representatives in the region. The successful promotion of these technologies by the MACEAC was accomplished through the following efforts; (1)The MACEAC developed a series of technology transfer networks with State energy and environmental offices, Association of Energy Engineers local chapters, local community development organizations, utilities and, Penn State Department of Architectural Engineering alumni and their firms to effectively educate local practitioners about the energy utilization, environmental and economic advantages of CHP, WHR and DES; (2) Completed assessments of the regional technical and market potential for CHP, WHR and DE technologies application in the context of state specific energy prices, state energy and efficiency portfolio development. The studies were completed for Pennsylvania, New Jersey and Maryland and included a set of incentive adoption probability models used as a to guide during implementation discussions with State energy policy makers; (3) Using the technical and market assessments and adoption incentive models, the Mid Atlantic CEAC developed regional strategic action plans for the promotion of CHP Application technology for Pennsylvania, New Jersey and Maryland; (4) The CHP market assessment and incentive adoption model information was discussed, on a continuing basis, with relevant state agencies, policy makers and Public Utility Commission organizations resulting in CHP favorable incentive

  11. Green-blue water in the city: quantification of impact of source control versus end-of-pipe solutions on sewer and river floods.

    Science.gov (United States)

    De Vleeschauwer, K; Weustenraad, J; Nolf, C; Wolfs, V; De Meulder, B; Shannon, K; Willems, P

    2014-01-01

    Urbanization and climate change trends put strong pressures on urban water systems. Temporal variations in rainfall, runoff and water availability increase, and need to be compensated for by innovative adaptation strategies. One of these is stormwater retention and infiltration in open and/or green spaces in the city (blue-green water integration). This study evaluated the efficiency of three adaptation strategies for the city of Turnhout in Belgium, namely source control as a result of blue-green water integration, retention basins located downstream of the stormwater sewers, and end-of-pipe solutions based on river flood control reservoirs. The efficiency of these options is quantified by the reduction in sewer and river flood frequencies and volumes, and sewer overflow volumes. This is done by means of long-term simulations (100-year rainfall simulations) using an integrated conceptual sewer-river model calibrated to full hydrodynamic sewer and river models. Results show that combining open, green zones in the city with stormwater retention and infiltration for only 1% of the total city runoff area would lead to a 30 to 50% reduction in sewer flood volumes for return periods in the range 10-100 years. This is due to the additional surface storage and infiltration and consequent reduction in urban runoff. However, the impact of this source control option on downstream river floods is limited. Stormwater retention downstream of the sewer system gives a strong reduction in peak discharges to the receiving river. However due to the difference in response time between the sewer and river systems, this does not lead to a strong reduction in river flood frequency. The paper shows the importance of improving the interface between urban design and water management, and between sewer and river flood management.

  12. Workshop on DNA repair.

    NARCIS (Netherlands)

    A.R. Lehmann (Alan); J.H.J. Hoeijmakers (Jan); A.A. van Zeeland (Albert); C.M.P. Backendorf (Claude); B.A. Bridges; A. Collins; R.P.D. Fuchs; G.P. Margison; R. Montesano; E. Moustacchi; A.T. Natarajan; M. Radman; A. Sarasin; E. Seeberg; C.A. Smith; M. Stefanini (Miria); L.H. Thompson; G.P. van der Schans; C.A. Weber (Christine); M.Z. Zdzienika

    1992-01-01

    textabstractA workshop on DNA repair with emphasis on eukaryotic systems was held, under the auspices of the EC Concerted Action on DNA Repair and Cancer, at Noordwijkerhout (The Netherlands) 14-19 April 1991. The local organization of the meeting was done under the auspices of the Medical Genetic C

  13. Laparoscopic lumbar hernia repair.

    Science.gov (United States)

    Madan, Atul K; Ternovits, Craig A; Speck, Karen E; Pritchard, F Elizabeth; Tichansky, David S

    2006-04-01

    Lumbar hernias are rare clinical entities that often pose a challenge for repair. Because of the surrounding anatomy, adequate surgical herniorraphy is often difficult. Minimally invasive surgery has become an option for these hernias. Herein, we describe two patients with lumbar hernias (one with a recurrent traumatic hernia and one with an incisional hernia). Both of these hernias were successfully repaired laparoscopically.

  14. Removal of nutrients from combined sewer overflows and lake water in a vertical-flow constructed wetland system.

    Science.gov (United States)

    Gervin, L; Brix, H

    2001-01-01

    Lake Utterslev is situated in a densely built-up area of Copenhagen, and is heavily eutrophicated from combined sewer overflows. At the same time the lake suffers from lack of water. Therefore, a 5,000 m2 vertical flow wetland system was constructed in 1998 to reduce the phosphorus discharge from combined sewer overflows without reducing the water supply to the lake. During dry periods the constructed wetland is used to remove phosphorus from the lake water. The system is designed as a 90 m diameter circular bed with a bed depth of c. 2 m. The system is isolated from the surroundings by a polyethylene membrane. The bed medium consists of a mixture of gravel and crushed marble, which has a high binding capacity for phosphorus. The bed is located within the natural littoral zone of the lake and is planted with common reed (Phragmites australis). The constructed wetland is intermittently loaded with combined sewer overflow water or lake water and, after percolation through the bed medium, the water is collected in a network of drainage pipes at the bottom of the bed and pumped to the lake. The fully automated loading cycle results in alternating wet and dry periods. During the initial two years of operation, the phosphorus removal for combined sewer overflows has been consistently high (94-99% of inflow concentrations). When loaded with lake water, the phosphorus removal has been high during summer (71-97%) and lower during winter (53-75%) partly because of lower inlet concentrations. Effluent phosphorus concentrations are consistently low (0.03-0.04 mg/L). Ammonium nitrogen is nitrified in the constructed wetland, and total suspended solids and COD are generally reduced to concentrations below 5 mg/L and 25 mg/L, respectively. The study documents that a subsurface flow constructed wetland system can be designed and operated to effectively remove phosphorus and other pollutants from combined sewer overflows and eutrophicated lake water.

  15. Mechanisms of single bubble cleaning.

    Science.gov (United States)

    Reuter, Fabian; Mettin, Robert

    2016-03-01

    The dynamics of collapsing bubbles close to a flat solid is investigated with respect to its potential for removal of surface attached particles. Individual bubbles are created by nanosecond Nd:YAG laser pulses focused into water close to glass plates contaminated with melamine resin micro-particles. The bubble dynamics is analysed by means of synchronous high-speed recordings. Due to the close solid boundary, the bubble collapses with the well-known liquid jet phenomenon. Subsequent microscopic inspection of the substrates reveals circular areas clean of particles after a single bubble generation and collapse event. The detailed bubble dynamics, as well as the cleaned area size, is characterised by the non-dimensional bubble stand-off γ=d/Rmax, with d: laser focus distance to the solid boundary, and Rmax: maximum bubble radius before collapse. We observe a maximum of clean area at γ≈0.7, a roughly linear decay of the cleaned circle radius for increasing γ, and no cleaning for γ>3.5. As the main mechanism for particle removal, rapid flows at the boundary are identified. Three different cleaning regimes are discussed in relation to γ: (I) For large stand-off, 1.8substrate and remove particles without significant contact of the gas phase. (II) For small distances, γsubstrate are driven by the jet impact with its subsequent radial spreading, and by the liquid following the motion of the collapsing and rebounding bubble wall. Both flows remove particles. Their relative timing, which depends sensitively on the exact γ, appears to determine the extension of the area with forces large enough to cause particle detachment. (III) At intermediate stand-off, 1.1substrate, but acts with cleaning mechanisms similar to an effective small γ collapse: particles are removed by the jet flow and the flow induced by the bubble wall oscillation. Furthermore, the observations reveal that the extent of direct bubble gas phase contact to the solid is partially smaller than the

  16. Wastewater effluent, combined sewer overflows, and other sources of organic compounds to Lake Champlain

    Science.gov (United States)

    Phillips, P.; Chalmers, A.

    2009-01-01

    Some sources of organic wastewater compounds (OWCs) to streams, lakes, and estuaries, including wastewater-treatment-plant effluent, have been well documented, but other sources, particularly wet-weather discharges from combined-sewer-overflow (CSO) and urban runoff, may also be major sources of OWCs. Samples of wastewater-treatment-plant (WWTP) effluent, CSO effluent, urban streams, large rivers, a reference (undeveloped) stream, and Lake Champlain were collected from March to August 2006. The highest concentrations of many OWCs associated with wastewater were in WWTP-effluent samples, but high concentrations of some OWCs in samples of CSO effluent and storm runoff from urban streams subject to leaky sewer pipes or CSOs were also detected. Total concentrations and numbers of compounds detected differed substantially among sampling sites. The highest total OWC concentrations (10-100 ??g/l) were in samples of WWTP and CSO effluent. Total OWC concentrations in samples from urban streams ranged from 0.1 to 10 ??g/l, and urban stream-stormflow samples had higher concentrations than baseflow samples because of contributions of OWCs from CSOs and leaking sewer pipes. The relations between OWC concentrations in WWTP-effluent and those in CSO effluent and urban streams varied with the degree to which the compound is removed through normal wastewater treatment. Concentrations of compounds that are highly removed during normal wastewater treatment [including caffeine, Tris(2-butoxyethyl)phosphate, and cholesterol] were generally similar to or higher in CSO effluent than in WWTP effluent (and ranged from around 1 to over 10 ??g/l) because CSO effluent is untreated, and were higher in urban-stream stormflow samples than in baseflow samples as a result of CSO discharge and leakage from near-surface sources during storms. Concentrations of compounds that are poorly removed during treatment, by contrast, are higher in WWTP effluent than in CSO, due to dilution. Results indicate

  17. DNA repair protocols

    DEFF Research Database (Denmark)

    Bjergbæk, Lotte

    In its 3rd edition, this Methods in Molecular Biology(TM) book covers the eukaryotic response to genomic insult including advanced protocols and standard techniques in the field of DNA repair. Offers expert guidance for DNA repair, recombination, and replication. Current knowledge of the mechanisms...... that regulate DNA repair has grown significantly over the past years with technology advances such as RNA interference, advanced proteomics and microscopy as well as high throughput screens. The third edition of DNA Repair Protocols covers various aspects of the eukaryotic response to genomic insult including...... recent advanced protocols as well as standard techniques used in the field of DNA repair. Both mammalian and non-mammalian model organisms are covered in the book, and many of the techniques can be applied with only minor modifications to other systems than the one described. Written in the highly...

  18. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Bill Bruce; Nancy Porter; George Ritter; Matt Boring; Mark Lozev; Ian Harris; Bill Mohr; Dennis Harwig; Robin Gordon; Chris Neary; Mike Sullivan

    2005-07-20

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without

  19. Megasonic cleaning: effect of dissolved gas properties on cleaning

    Science.gov (United States)

    Shende, Hrishi; Singh, Sherjang; Baugh, James; Dietze, Uwe; Dress, Peter

    2013-06-01

    Current and future lithography techniques require complex imaging improvement strategies. These imaging improvement strategies require printing of sub-resolution assist-features (SRAF) on photomasks. The size of SRAF's has proven to be the main limiting factor in using high power Megasonic cleaning process on photomasks. These features, due to high aspect ratio are more prone to damage at low Megasonic frequencies and at high Megasonic powers. Additionally the non-uniformity of energy dissipated during Megasonic cleaning is a concern for exceeding the damage threshold of the SRAFs. If the cavitation events during Megasonic cleaning are controlled in way to dissipate uniform energy, better process control can be achieved to clean without damage. The amount and type of gas dissolved in the cleaning liquid defines the cavitation behavior. Some of the gases possess favourable solubility and adiabatic properties for stable and controlled cavitation behaviour. This paper particularly discusses the effects of dissolved Ar gas on Megasonic characteristics. The effect of Ar Gas is characterized by measuring acoustic energy and Sonoluminscense. The phenomenon is further verified with pattern damage studies.

  20. Electromagnetically Clean Solar Arrays

    Science.gov (United States)

    Stem, Theodore G.; Kenniston, Anthony E.

    2008-01-01

    The term 'electromagnetically clean solar array' ('EMCSA') refers to a panel that contains a planar array of solar photovoltaic cells and that, in comparison with a functionally equivalent solar-array panel of a type heretofore used on spacecraft, (1) exhibits less electromagnetic interferences to and from other nearby electrical and electronic equipment and (2) can be manufactured at lower cost. The reduction of electromagnetic interferences is effected through a combination of (1) electrically conductive, electrically grounded shielding and (2) reduction of areas of current loops (in order to reduce magnetic moments). The reduction of cost is effected by designing the array to be fabricated as a more nearly unitary structure, using fewer components and fewer process steps. Although EMCSAs were conceived primarily for use on spacecraft they are also potentially advantageous for terrestrial applications in which there are requirements to limit electromagnetic interference. In a conventional solar panel of the type meant to be supplanted by an EMCSA panel, the wiring is normally located on the back side, separated from the cells, thereby giving rise to current loops having significant areas and, consequently, significant magnetic moments. Current-loop geometries are chosen in an effort to balance opposing magnetic moments to limit far-0field magnetic interactions, but the relatively large distances separating current loops makes full cancellation of magnetic fields problematic. The panel is assembled from bare photovoltaic cells by means of multiple sensitive process steps that contribute significantly to cost, especially if electomagnetic cleanliness is desired. The steps include applying a cover glass and electrical-interconnect-cell (CIC) sub-assemble, connecting the CIC subassemblies into strings of series-connected cells, laying down and adhesively bonding the strings onto a panel structure that has been made in a separate multi-step process, and mounting the

  1. A method and device for cleaning air

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to a method and device for cleaning pollution from air wherin the air to be cleaned is subjected to a sequence of physical and chemical treatments.......The present invention relates to a method and device for cleaning pollution from air wherin the air to be cleaned is subjected to a sequence of physical and chemical treatments....

  2. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-12-31

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without

  3. Are Breast Surgical Operations Clean or Clean Contaminated?

    Science.gov (United States)

    Kataria, Kamal; Bagdia, Amit; Srivastava, Anurag

    2015-12-01

    The breast surgeries are classically taught as clean surgical procedures. The infection rates following breast surgery ranges from 3 to 15 %, which is much higher than infection rates after clean surgery (ranging from 1.5 to 3 %). This high infection rate following breast surgery can be explained by opening of the ductal system to outside world through nipple similar to the gastrointestinal and genitourinary system. We conducted a systematic review of infection following breast surgeries. We searched various randomized controlled trials, meta-analysis, and Cochrane Reviews over PubMed and Medline via the Internet. These evidences were found to support the thesis, "Breast surgeries need to be reclassified as clean-contaminated". We recommend the use of prophylactic antibiotics in breast surgery.

  4. Reliability of adaptive multivariate software sensors for sewer water quality monitoring

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen

    2015-01-01

    mainly originated from wastewater sources (such as ammonia) than when used for pollutants affected by several processes (such as TSS). Overall, this study provides a first insight in the application of multivariate methods for software sensors, highlighting drawback and potential development areas......This study investigates the use of a multivariate approach, based on Principal Component Analysis PCA), as software sensor for fault detection and reconstruction of missing measurements in on-line monitoring of sewer water quality. The analysis was carried out on a 16-months dataset of five...... validation. However, the study also showed a dramatic drop in predictive capability of the software sensor when used for reconstructing missing values, with performance quickly deteriorating after 1 week since parameter estimation. The software sensor provided better results when used to estimate pollutants...

  5. Development of a glass polymer composite sewer pipe from waste glass. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rayfiel, R.; Kukacka, L.E.

    1980-02-01

    A range of polymer-aggregate composites for applications in industry which appear to be economically attractive and contribute to energy conservation were developed at BNL. Waste glass is the aggregate in one such material, which is called glass-polymer-composite (GPC). This report assays the economics and durability of GPC in piping for storm drains and sewers. The properties of the pipe are compared statistically with the requirements of industrial specifications. These establish the raw materials requirements. The capital and operating costs for producing pipe are then estimated. Using published sales values for competing materials, the return on investment is calculated for two cases. The ultimate energy requirement of the raw materials in GPC is compared with the corresponding requirement for vitrified clay pipe. The strengths of GPC, reinforced concrete, vitrified clay and asbestos cement pipe are compared after extended exposure to various media. The status of process and product development is reviewed and recommendations are made for future work.

  6. Combined sewer overflows: an environmental source of hormones and wastewater micropollutants

    Science.gov (United States)

    Phillips, P.J.; Chalmers, A.T.; Gray, J.L.; Kolpin, D.W.; Foreman, W.T.; Wall, G.R.

    2012-01-01

    Data were collected at a wastewater treatment plant (WWTP) in Burlington, Vermont, USA, (serving 30,000 people) to assess the relative contribution of CSO (combined sewer overflow) bypass flows and treated wastewater effluent to the load of steroid hormones and other wastewater micropollutants (WMPs) from a WWTP to a lake. Flow-weighted composite samples were collected over a 13 month period at this WWTP from CSO bypass flows or plant influent flows (n = 28) and treated effluent discharges (n = 22). Although CSO discharges represent 10% of the total annual water discharge (CSO plus treated plant effluent discharges) from the WWTP, CSO discharges contribute 40–90% of the annual load for hormones and WMPs with high (>90%) wastewater treatment removal efficiency. By contrast, compounds with low removal efficiencies (hormones and many WMPs in samples from treated discharges can increase with increasing flow due to decreasing removal efficiency.

  7. Experimental and Numerical Analysis of Egg-Shaped Sewer Pipes Flow Performance

    Directory of Open Access Journals (Sweden)

    Manuel Regueiro-Picallo

    2016-12-01

    Full Text Available A Computational Fluid Dynamics (CFD model was developed to analyze the open-channel flow in a new set of egg-shaped pipes for small combined sewer systems. The egg-shaped cross-section was selected after studying several geometries under different flow conditions. Once the egg-shaped cross-section was defined, a real-scale physical model was built and a series of partial-full flow experiments were performed in order to validate the numerical simulations. Furthermore, the numerical velocity distributions were compared with an experimental formulation for analytic geometries, with comparison results indicating a satisfactory concordance. After the hydraulic performance of the egg-shaped pipe was analyzed, the numerical model was used to compare the average velocity and shear stress against an equivalent area circular pipe under low flow conditions. The proposed egg shape showed a better flow performance up to a filling ratio of h/H = 0.25.

  8. Sulfate attack in sewer pipes: Derivation of a concrete corrosion model via two-scale convergence

    CERN Document Server

    Fatima, Tasnim

    2010-01-01

    We explore the homogenization limit and rigorously derive upscaled equations for a microscopic reaction-diffusion system modeling sulfate corrosion in sewer pipes made of concrete. The system, defined in a periodically-perforated domain, is semi-linear, partially dissipative and weakly coupled via a non-linear ordinary differential equation posed on the solid-water interface at the pore level. Firstly, we show the well-posedness of the microscopic model. We then apply homogenization techniques based on two-scale convergence for an uniformly periodic domain and derive upscaled equations together with explicit formulae for the effective diffusion coefficients and reaction constants. We use a boundary unfolding method to pass to the homogenization limit in the non-linear ordinary differential equation. Finally, besides giving its strong formulation, we also prove that the upscaled two-scale model admits a unique solution.

  9. Modeling of hydrogen sulfide oxidation in concrete corrosion products from sewer pipes.

    Science.gov (United States)

    Jensen, Henriette Stokbro; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes

    2009-04-01

    Abiotic and biotic oxidation of hydrogen sulfide related to concrete corrosion was studied in corrosion products originating from a sewer manhole. The concrete corrosion products were suspended in an acidic solution, mimicking the conditions in the pore water of corroded concrete. The removal of hydrogen sulfide and dissolved oxygen was measured in parallel in the suspension, upon which the suspension was sterilized and the measurement repeated. The results revealed the biotic oxidation to be fast compared with the abiotic oxidation. The stoichiometry of the hydrogen sulfide oxidation was evaluated using the ratio between oxygen and hydrogen sulfide uptake. The ratio for the biotic oxidation pointed in the direction of elemental sulfur being formed as an intermediate in the oxidation of hydrogen sulfide to sulfuric acid. The experimental results were applied to suggest a hypothesis and a mathematical model describing the hydrogen sulfide oxidation pathway in a matrix of corroded concrete.

  10. Toxicity of combined sewer overflows on river phytoplankton: the role of heavy metals.

    Science.gov (United States)

    Seidl, M; Huang, V; Mouchel, J M

    1998-01-01

    The toxic effect of a combined sewer overflow (CSO) on the phytoplankton community of the river Seine has been studied by means of short-term primary production measurements. As the discharged solids usually do not remain in the water column, only filtered or centrifugated fractions were tested. The collected phytoplankton were grown in the laboratory for 2 days, after addition of N, P and EDTA. Stock cultures in exponential growth were directly tested with heavy metals, but resuspended algal cells were used for effluent testing. The results show an increase of EC50 value for the single metal species in the order Cu

  11. Modeling climate change impacts on combined sewer overflow using synthetic precipitation time series.

    Science.gov (United States)

    Bendel, David; Beck, Ferdinand; Dittmer, Ulrich

    2013-01-01

    In the presented study climate change impacts on combined sewer overflows (CSOs) in Baden-Wuerttemberg, Southern Germany, were assessed based on continuous long-term rainfall-runoff simulations. As input data, synthetic rainfall time series were used. The applied precipitation generator NiedSim-Klima accounts for climate change effects on precipitation patterns. Time series for the past (1961-1990) and future (2041-2050) were generated for various locations. Comparing the simulated CSO activity of both periods we observe significantly higher overflow frequencies for the future. Changes in overflow volume and overflow duration depend on the type of overflow structure. Both values will increase at simple CSO structures that merely divide the flow, whereas they will decrease when the CSO structure is combined with a storage tank. However, there is a wide variation between the results of different precipitation time series (representative for different locations).

  12. Assessing combined sewer overflows with long lead time for better surface water management.

    Science.gov (United States)

    Abdellatif, Mawada; Atherton, William; Alkhaddar, Rafid

    2014-01-01

    During high-intensity rainfall events, the capacity of combined sewer overflows (CSOs) can exceed resulting in discharge of untreated stormwater and wastewater directly into receiving rivers. These discharges can result in high concentrations of microbial pathogens, biochemical oxygen demand, suspended solids, and other pollutants in the receiving waters. The frequency and severity of the CSO discharge are strongly influenced by climatic factors governing the occurrence of urban stormwater runoff, particularly the amount and intensity of the rainfall. This study attempts to assess the impact of climate change (change in rainfall amount and frequency) on CSO under the high (A1FI) and low (B1) Special Report on Emissions Scenarios of the greenhouse concentration derived from three global circulation models in the north west of England at the end of the twenty-first century.

  13. [Study on the characteristics of combined sewer overflow from the high density residential area in Shanghai].

    Science.gov (United States)

    Li, He; Li, Tian

    2006-08-01

    The urban non-point pollution has become main pollution resource of urban water bodies of Shanghai. Character of combined sewer overflow from watershed SA in Shanghai was studied, and the correlation of influence factors to the EMCs of overflows was discussed. It is found that the EMCs of COD, BOD, SS, NH3-N, TN, TP are 614 mg/L, 208.5 mg/L, 684 mg/L, 17.6 mg/L, 29.8 mg/L, 3.0 mg/L respectively, and the values obtained herein are much higher than the documented data from other countries. From the probability plot of the EMCs, it is found that the BOD has the best fitness for lognormal distribution; and correlation between the EMCs of COD, SS and the ratio of antecedent dry weather time to rain duration is quite good.

  14. Determination of kinetics and stoichiometry of chemical sulfide oxidation in wastewater of sewer networks

    DEFF Research Database (Denmark)

    Nielsen, A.H.; Vollertsen, Jes; Hvitved-jacobsen, Thorkild

    2003-01-01

    A method for determination of kinetics and stoichiometry of chemical sulfide oxidation by dissolved oxygen (DO) in wastewater is presented. The method was particularly developed to investigate chemical sulfide oxidation in wastewater of sewer networks at low DO concentrations. The method is based...... parameters determined in a triplicate experiment. The kinetic parameters determined in 25 experiments on wastewater samples from a single site exhibited good constancy with a variation of the same order of magnitude as the precision of the method. It was found that the stoichiometry of the reaction could...... be considered constant during the course of the experiments although intermediates accumulated. This was explained by an apparent slow oxidation rate of the intermediates. The method was capable of determining kinetics and stoichiometry of chemical sulfide oxidation at DO concentrations lower than 1 g of O2 m...

  15. Cleaning properties of dry adhesives

    Institute of Scientific and Technical Information of China (English)

    J.; P.; DíAZ; TéLLEZ; D.; SAMEOTO; C.; MENON

    2010-01-01

    In this paper we present a study into the cleaning properties of synthetic dry adhesives. We have manufactured the adhesive micro-fibres through a low-cost, high yield fabrication method using Sylgard 184 Polydimethylsiloxane (PDMS) as the structural material. We deliberately contaminated the adhesive samples with different sized particles in the micro and macro scales and tested different cleaning methods for their efficacy with respect to each particle size. We investigated different cleaning methods, which included the use of wax moulding, vibration and pressure sensitive adhesives. For adhesion testing we used a custom system with a linear stage and a force sensor indenting a hemispherical probe into the adhesive surface and measuring the pull-off force. To characterize the cleaning efficacy we visually inspected each sample in a microscope and weighed the samples with a microgram-accuracy analytical balance. Results showed that the moulding method induced adhesion recovery in a greater percentage than the other cleaning methods and even helped with the recovery of collapsed posts in some cases. On the other hand pressure sensitive adhesives seem to have the upper hand with regards to certain particle sizes that can potentially pose problems with the moulding method.

  16. Evaluation of Sulfide Control by Air-Injection in Sewer Force Mains: Field and Laboratory Study

    Directory of Open Access Journals (Sweden)

    Juan T. García

    2017-03-01

    Full Text Available Chemical and biological processes consume dissolved oxygen (DO in urban wastewater during transportation along sewer systems. Anaerobic conditions (DO < 0.2 mg/L are easily reached, leading to sulfide (S2− generation. Release of free sulfide, hydrogen sulfide gas (H2S, from the liquid to the gaseous phase, causes odor, corrosion of pipes and supposes a risk for health of people working in sewers. These issues get worse in force mains, due to inability to take oxygen from the gaseous phase of pipe. Air injection is a suggested practice to control H2S emission in force mains. That technique aims to keep aerobic conditions in wastewater in order to avoid sulfide generation and favor a decrease of Biochemical Organic Demand (BOD. However, several force mains with air injection are not achieving their goals due to a limited oxygen transfer. Field measurements of dissolved oxygen in urban wastewater are presented in an existing force main with air injection during the summer of 2014 in the southeast of Spain. A laboratory scale model is constructed to quantify two-phase flow conditions in pipe due to air injection for different incoming flows rates of water and air. Particularly, for the case of plug flow, also known as elongated bubble flow. Velocity field measurement of water phase in laboratory allows estimating turbulent diffusivity of oxygen in the water, Em, and inter-phase mass transfer coefficient KL(T. In the laboratory, flow and air depth, bubble length, water velocity field, pressure inside force main and water and airflow rates are determined experimentally. These variables are used to assess DO in water phase of force main by comparison with those obtained from field measurements. This work allows assessing air injection efficiency in wastewater, and, therefore, to predict DO in wastewater in force mains.

  17. Organic micropollutants discharged by combined sewer overflows - Characterisation of pollutant sources and stormwater-related processes.

    Science.gov (United States)

    Launay, Marie A; Dittmer, Ulrich; Steinmetz, Heidrun

    2016-11-01

    To characterise emissions from combined sewer overflows (CSOs) regarding organic micropollutants, a monitoring study was undertaken in an urban catchment in southwest Stuttgart, Germany. The occurrence of 69 organic micropollutants was assessed at one CSO outfall during seven rain events as well as in the sewage network at the influent of the wastewater treatment plant (WWTP) and in the receiving water. Several pollutant groups like pharmaceuticals and personal care products (PPCPs), urban biocides and pesticides, industrial chemicals, organophosphorus flame retardants, plasticisers and polycyclic aromatic hydrocarbons (PAHs) were chosen for analysis. Out of the 69 monitored substances, 60 were detected in CSO discharges. The results of this study show that CSOs represent an important pathway for a wide range of organic micropollutants from wastewater systems to urban receiving waters. For most compounds detected in CSO samples, event mean concentrations varied between the different events in about one order of magnitude range. When comparing CSO concentrations with median wastewater concentrations during dry weather, two main patterns could be observed depending on the source of the pollutant: (i) wastewater is diluted by stormwater; (ii) stormwater is the most important source of a pollutant. Both wastewater and stormwater only play an important role in pollutant concentration for a few compounds. The proportion of stormwater calculated with the conductivity is a suitable indicator for the evaluation of emitted loads of dissolved wastewater pollutants, but not for all compounds. In fact, this study demonstrates that remobilisation of in-sewer deposits contributed from 10% to 65% to emissions of carbamazepine in CSO events. The contribution of stormwater to CSO emitted loads was higher than 90% for all herbicides as well as for PAHs. Regarding the priority substance di(2-ethylhexyl)phthalate (DEHP), this contribution varied between 39% and 85%. The PAH

  18. Modelling the impacts of Combined Sewer Overflows on the river Seine water quality.

    Science.gov (United States)

    Even, Stéphanie; Mouchel, Jean-Marie; Servais, Pierre; Flipo, Nicolas; Poulin, Michel; Blanc, Stéphanie; Chabanel, Matthieu; Paffoni, Catherine

    2007-04-01

    To achieve the objectives of the European Water Framework Directive (EWFD), the Seine basin Water Authority has constructed a number of prospective scenarios forecasting the impact of planned investments in water quality. Paris and its suburbs were given special attention because of their impact on the river Seine. Paris sewer system and overflow control is of major concern in future management plans. The composition and fate of the urban effluents have been characterized through numerous in situ samplings, laboratory experiments and modelling studies. The PROSE model was especially designed to simulate the impact on the river of both permanent dry-weather effluents and of highly transient Combined Sewer Overflow (CSO). It was also used to represent the impact of Paris at large spatial and temporal scales. In addition to immediate effects on oxygen levels, heavy particulate organic matter loads that settle downstream of the outlets contribute to permanent oxygen consumption. Until the late 90s, the 50 km long reach of the Seine inside Paris was permanently affected by high oxygen consumption accounting for 112% of the flux upstream of the city. 20% of this demand resulted from CSO. However, the oxygenation of the system is strong due to high phytoplankton activity. As expected, the model results predict a reduction of both permanent dry-weather effluents and CSOs in the future that will greatly improve the oxygen levels (concentrations higher than 7.3 mgO(2) L(-1), 90% of the time instead of 4.0 mgO(2) L(-1) in the late 90s). The main conclusion is that, given the spatial and temporal extent of the impact of many CSOs, water quality models should take into account the CSOs in order to be reliable.

  19. Cumulative effects of fecal contamination from combined sewer overflows: Management for source water protection.

    Science.gov (United States)

    Jalliffier-Verne, Isabelle; Heniche, Mourad; Madoux-Humery, Anne-Sophie; Galarneau, Martine; Servais, Pierre; Prévost, Michèle; Dorner, Sarah

    2016-06-01

    The quality of a drinking water source depends largely on upstream contaminant discharges. Sewer overflows can have a large influence on downstream drinking water intakes as they discharge untreated or partially treated wastewaters that may be contaminated with pathogens. This study focuses on the quantification of Escherichia coli discharges from combined sewer overflows (CSOs) and the dispersion and diffusion in receiving waters in order to prioritize actions for source water protection. E. coli concentrations from CSOs were estimated from monitoring data at a series of overflow structures and then applied to the 42 active overflow structures between 2009 and 2012 using a simple relationship based upon the population within the drainage network. From these estimates, a transport-dispersion model was calibrated with data from a monitoring program from both overflow structures and downstream drinking water intakes. The model was validated with 15 extreme events such as a large number of overflows (n > 8) or high concentrations at drinking water intakes. Model results demonstrated the importance of the cumulative effects of CSOs on the degradation of water quality downstream. However, permits are typically issued on a discharge point basis and do not consider cumulative effects. Source water protection plans must consider the cumulative effects of discharges and their concentrations because the simultaneous discharge of multiple overflows can lead to elevated E. coli concentrations at a drinking water intake. In addition, some CSOs have a disproportionate impact on peak concentrations at drinking water intakes. As such, it is recommended that the management of CSOs move away from frequency based permitting at the discharge point to focus on the development of comprehensive strategies to reduce cumulative and peak discharges from CSOs upstream of drinking water intakes.

  20. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-08-17

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners

  1. Salvage hypospadias repairs

    Directory of Open Access Journals (Sweden)

    Sripathi V

    2008-01-01

    Full Text Available Aim: Review of our experience and to develop an algorithm for salvage procedures in the management of hypospadias cripples and treatment of urethral strictures following hypospadias repair. Methods: This is a retrospective review of hypospadias surgeries over a 41-month period. Out of a total 168 surgeries, 20 were salvage/re-operative repairs. In three children a Duplay repair was feasible, while in four others a variety of single-stage repairs could be done. The repair was staged in seven children - buccal mucosal grafts (BMGs in five, buccal mucosal tube in one, and skin graft in one. Five children with dense strictures were managed by dorsal BMG inlay grafting in one, vascularized tunical onlay grafting on the ventrum in one, and a free tunical patch in one. Three children were treated by internal urethrotomy and stenting for four weeks with a poor outcome. Results: The age of children ranged from 1.5-15 years (mean 4.5. Follow-up ranged from 3 months to 3.5 years. Excellent results were obtained in 10 children (50% with a well-surfaced erect penis and a slit-like meatus. Glans closure could not be achieved and meatus was coronal in three. Two children developed fistulae following a Duplay repair and following a staged BMG. Three repairs failed completely - a composite repair broke down, a BMG tube stenosed with a proximal leak, and a stricture recurred with loss of a ventral free tunical graft. Conclusions: In salvage procedures performed on hypospadias cripples, a staged repair with buccal mucosa as an inlay in the first stage followed by tubularization 4-6 months later provides good results. A simple algorithm to plan corrective surgery in failed hypospadias cases and obtain satisfactory results is devised.

  2. Laser cleaning of tungsten ribbon

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Aniruddha, E-mail: nontee65@rediffmail.com [Advanced Fuel Fabrication Facility, Bhabha Atomic Research Centre, Tarapur, Maharashtra, 401504 (India); Sonar, V.R.; Das, D.K.; Bhatt, R.B.; Behere, P.G.; Afzal, Mohd.; Kumar, Arun [Advanced Fuel Fabrication Facility, Bhabha Atomic Research Centre, Tarapur, Maharashtra, 401504 (India); Nilaya, J.P.; Biswas, D.J. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, 400085 (India)

    2014-07-01

    Removal of a thin oxide layer from a tungsten ribbon was achieved using the fundamental, second and third harmonic radiation from a Q- switched Nd-YAG laser. It was found that beyond the threshold, oxide removal was achieved at all wavelengths for a wide range of fluence values. The removal mechanism of the oxide layer was found to be critically dependent on both wavelength and fluence of the incident radiation and has been identified as ejection or sublimation. The un-cleaned and cleaned surfaces were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS) and atomic force microscopy (AFM). Laser cleaned tungsten ribbons were used in a thermal ionization mass spectrometer (TIMS) to determine isotopic composition of Neodymium atoms.

  3. Clean Air OnLine

    Energy Technology Data Exchange (ETDEWEB)

    Finney, D. [Environment Canada, Gatineau, PQ (Canada). Air Pollution Prevention Directorate

    2004-04-07

    This presentation describes Clean Air OnLine, a multi-tiered website dedicated to providing Canadians with information on air quality. The website is under development to support action to reduce air emissions, demonstrate the links between air emissions and environmental impacts, and enhance the understanding of sustainable community development issues such as health, energy, and urban sprawl. Partners in the Clean Air OnLine (CAOL) initiative include Environment Canada and the Clean Air Partnership which includes the Greater Toronto Area pilot project. The audience for CAOL includes municipal decision makers, local decision makers, community leaders, and the general public. The project provides Canadians with air pollution contextual information on pollution sources, pollutants, and related issues. It also provides information on health, environmental and economic impacts and the interrelationships with climate change issues and energy use. tabs., figs.

  4. Clean air in the Anthropocene.

    Science.gov (United States)

    Lelieveld, Jos

    2017-08-24

    In atmospheric chemistry, interactions between air pollution, the biosphere and human health, often through reaction mixtures from both natural and anthropogenic sources, are of growing interest. Massive pollution emissions in the Anthropocene have transformed atmospheric composition to the extent that biogeochemical cycles, air quality and climate have changed globally and partly profoundly. It is estimated that mortality attributable to outdoor air pollution amounts to 4.33 million individuals per year, associated with 123 million years of life lost. Worldwide, air pollution is the major environmental risk factor to human health, and strict air quality standards have the potential to strongly reduce morbidity and mortality. Preserving clean air should be considered a human right, and is fundamental to many sustainable development goals of the United Nations, such as good health, climate action, sustainable cities, clean energy, and protecting life on land and in the water. It would be appropriate to adopt "clean air" as a sustainable development goal.

  5. Clean Coal Diesel Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Robert Wilson

    2006-10-31

    A Clean Coal Diesel project was undertaken to demonstrate a new Clean Coal Technology that offers technical, economic and environmental advantages over conventional power generating methods. This innovative technology (developed to the prototype stage in an earlier DOE project completed in 1992) enables utilization of pre-processed clean coal fuel in large-bore, medium-speed, diesel engines. The diesel engines are conventional modern engines in many respects, except they are specially fitted with hardened parts to be compatible with the traces of abrasive ash in the coal-slurry fuel. Industrial and Municipal power generating applications in the 10 to 100 megawatt size range are the target applications. There are hundreds of such reciprocating engine power-plants operating throughout the world today on natural gas and/or heavy fuel oil.

  6. Senate passes clean air bill

    Science.gov (United States)

    In an 89 to 11 vote the Senate passed a clean air bill aimed at reducing pollution by the turn of the century by imposing tougher controls on American industry. The bill is the first revision of the Clean Air Act of 1970 in 13 years and calls for new limits on auto pollution to clean up smog in most U.S. cities, decreasing by half emissions by power plants that cause acid rain to protect the ecology, and increasing technological controls on factories to protect against cancer-causing and toxic substances. The bill will add about $20 billion per year to the estimated $33 billion cost of complying with current pollution laws.

  7. Hyperbolic Divergence Cleaning for SPH

    CERN Document Server

    Tricco, Terrence S

    2012-01-01

    We present SPH formulations of Dedner et al's hyperbolic/parabolic divergence cleaning scheme for magnetic and velocity fields. Our implementation preserves the conservation properties of SPH which is important for stability. This is achieved by deriving an energy term for the Psi field, and imposing energy conservation on the cleaning subsystem of equations. This necessitates use of conjugate operators for divB and gradPsi in the numerical equations. For both the magnetic and velocity fields, the average divergence error in the system is reduced by an order of magnitude with our cleaning algorithm. Divergence errors in SPMHD are maintained to < 1%, even for realistic 3D applications with a corresponding gain in numerical stability. Density errors for an oscillating elliptic water drop using weakly compressible SPH are reduced by a factor of two.

  8. Green Solvents for Precision Cleaning

    Science.gov (United States)

    Grandelli, Heather; Maloney, Phillip; DeVor, Robert; Surma, Jan; Hintze, Paul

    2013-01-01

    Aerospace machinery used in liquid oxygen (LOX) fuel systems must be precision cleaned to achieve a very low level of non-volatile residue (< 1 mg0.1 m2), especially flammable residue. Traditionally chlorofluorocarbons (CFCs) have been used in the precision cleaning of LOX systems, specifically CFC 113 (C2Cl3F3). CFCs have been known to cause the depletion of ozone and in 1987, were banned by the Montreal Protocol due to health, safety and environmental concerns. This has now led to the development of new processes in the precision cleaning of aerospace components. An ideal solvent-replacement is non-flammable, environmentally benign, non-corrosive, inexpensive, effective and evaporates completely, leaving no residue. Highlighted is a green precision cleaning process, which is contaminant removal using supercritical carbon dioxide as the environmentally benign solvent. In this process, the contaminant is dissolved in carbon dioxide, and the parts are recovered at the end of the cleaning process completely dry and ready for use. Typical contaminants of aerospace components include hydrocarbon greases, hydraulic fluids, silicone fluids and greases, fluorocarbon fluids and greases and fingerprint oil. Metallic aerospace components range from small nuts and bolts to much larger parts, such as butterfly valves 18 in diameter. A fluorinated grease, Krytox, is investigated as a model contaminant in these preliminary studies, and aluminum coupons are employed as a model aerospace component. Preliminary studies are presented in which the experimental parameters are optimized for removal of Krytox from aluminum coupons in a stirred-batch process. The experimental conditions investigated are temperature, pressure, exposure time and impeller speed. Temperatures of 308 - 423 K, pressures in the range of 8.3 - 41.4 MPa, exposure times between 5 - 60 min and impeller speeds of 0 - 1000 rpm were investigated. Preliminary results showed up to 86 cleaning efficiency with the

  9. Laser paper cleaning: the method of cleaning historical books

    Science.gov (United States)

    Zekou, Evangelini; Tsilikas, Ioannis; Chatzitheodoridis, Elias; Serafetinides, Alexander A.

    2016-01-01

    Conservation of cultural heritage treasures is the most important issue for transferring knowledge to the public through the next generation of students, academics, and researchers. Although this century is authenticating e-books and information by means of electronic text, still historical manuscripts as content as well as objects are the main original recourses of keeping a record of this transformation. The current work focuses on cleaning paper samples by the application of pulsed light, which is interventional. Experiments carried out using paper samples that are artificially colonized with Ulocladium chartarum. Paper is treated by Nd:YAG laser light. The available wavelength is 1064 nm, at various fluences, repetition rates and number of pulses. Two types of paper are stained with fungi colonies, which grow on substrates of clean paper, as well as on paper with ink text. The first type of paper is Whatman No.1056, which is closer to pure cellulose. The second type of paper is a page of a cultural heritage book published in 1926. Cleaning is performed using laser irradiation, thus defining the damage threshold of each sample. The treatment on paper Watman showed a yellowing, especially on areas with high concentration of fungi. The second sample was more durable to the exposure, performing the best results at higher fluences. Eventually, the paper samples are characterized, with optical microscopy and SEM/EDX analyses, prior to and after cleaning.

  10. 300 Area process sewer piping upgrade and 300 Area treated effluent disposal facility discharge to the City of Richland Sewage System, Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The U.S. Department of Energy (DOE) is proposing to upgrade the existing 300 Area Process Sewer System by constructing and operating a new process sewer collection system that would discharge to the 300 Area Treated Effluent Disposal Facility. The DOE is also considering the construction of a tie-line from the TEDF to the 300 Area Sanitary Sewer for discharging the process wastewater to the City of Richland Sewage System. The proposed action is needed because the integrity of the old piping in the existing 300 Area Process Sewer System is questionable and effluents might be entering the soil column from leaking pipes. In addition, the DOE has identified a need to reduce anticipated operating costs at the new TEDF. The 300 Area Process Sewer Piping Upgrade (Project L-070) is estimated to cost approximately $9.9 million. The proposed work would involve the construction and operation of a new process sewer collection system. The new system would discharge the effluents to a collection sump and lift station for the TEDF. The TEDF is designed to treat and discharge the process effluent to the Columbia River. The process waste liquid effluent is currently well below the DOE requirements for radiological secondary containment and is not considered a RCRA hazardous waste or a State of Washington Hazardous Waste Management Act dangerous waste. A National Pollutant Discharge Elimination, System (NPDES) permit has been obtained from the U.S. Environmental Protection Agency for discharge to the Columbia River. The proposed action would upgrade the existing 300 Area Process Sewer System by the construction and operation of a new combined gravity, vacuum, and pressurized process sewer collection system consisting of vacuum collection sumps, pressure pump stations, and buried polyvinyl chloride or similar pipe. Two buildings would also be built to house a main collection station and a satellite collection station.

  11. Progress of peripheral nerve repair

    Institute of Scientific and Technical Information of China (English)

    陈峥嵘

    2002-01-01

    Study on repair of peripheral nerve injury has been proceeding over a long period of time. With the use of microsurgery technique since 1960s,the quality of nerve repair has been greatly improved. In the past 40 years, with the continuous increase of surgical repair methods, more progress has been made on the basic research of peripheral nerve repair.

  12. Achilles tendon repair

    Science.gov (United States)

    Achilles tendon rupture-surgery; Percutaneous Achilles tendon rupture repair ... To fix your torn Achilles tendon, the surgeon will: Make a cut down the back of your heel Make several small cuts rather than one large cut ...

  13. Diaphragmatic hernia repair - slideshow

    Science.gov (United States)

    ... presentations/100014.htm Diaphragmatic hernia repair - series—Normal anatomy To use the sharing ... Overview The chest cavity includes the heart and lungs. The abdominal cavity includes the liver, the stomach, ...

  14. Eye muscle repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  15. Tracheoesophageal fistula repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100103.htm Tracheoesophageal fistula repair - series—Normal anatomy To use the sharing ... Editorial team. Related MedlinePlus Health Topics Esophagus Disorders Fistulas Tracheal Disorders A.D.A.M., Inc. is ...

  16. Inguinal hernia repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100027.htm Inguinal hernia repair - series—Normal anatomy To use the sharing ... to slide 4 out of 4 Overview A hernia occurs when part of an organ protrudes through ...

  17. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; Nancy Porter; Mike Sullivan; Chris Neary

    2004-04-12

    The two broad categories of deposited weld metal repair and fiber-reinforced composite liner repair technologies were reviewed for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Preliminary test programs were developed for both deposited weld metal repair and for fiber-reinforced composite liner repair. Evaluation trials have been conducted using a modified fiber-reinforced composite liner provided by RolaTube and pipe sections without liners. All pipe section specimens failed in areas of simulated damage. Pipe sections containing fiber-reinforced composite liners failed at pressures marginally greater than the pipe sections without liners. The next step is to evaluate a liner material with a modulus of elasticity approximately 95% of the modulus of elasticity for steel. Preliminary welding parameters were developed for deposited weld metal repair in preparation of the receipt of Pacific Gas & Electric's internal pipeline welding repair system (that was designed specifically for 559 mm (22 in.) diameter pipe) and the receipt of 559 mm (22 in.) pipe sections from Panhandle Eastern. The next steps are to transfer welding parameters to the PG&E system and to pressure test repaired pipe sections to failure. A survey of pipeline operators was conducted to better understand the needs and performance requirements of the natural gas transmission industry regarding internal repair. Completed surveys contained the following principal conclusions: (1) Use of internal weld repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling (HDD) when a new bore must be created

  18. Pectus excavatum repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100035.htm Pectus excavatum repair - series—Normal anatomy To use the sharing ... Go to slide 4 out of 4 Overview Pectus excavatum is a deformity of the front of the ...

  19. Hiatal hernia repair - slideshow

    Science.gov (United States)

    ... presentations/100028.htm Hiatal hernia repair - series—Normal anatomy To use the sharing features on ... Overview The esophagus runs through the diaphragm to the stomach. It functions to carry food from the mouth ...

  20. Repairing ceramic insulating tiles

    Science.gov (United States)

    Dunn, B. R.; Laymance, E. L.

    1980-01-01

    Fused-silica tiles containing large voids or gauges are repaired without adhesives by plug insertion method. Tiles are useful in conduits for high-temperature gases, in furnaces, and in other applications involving heat insulation.

  1. Rotator cuff repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100229.htm Rotator cuff repair - series—Normal anatomy To use the sharing ... to slide 4 out of 4 Overview The rotator cuff is a group of muscles and tendons that ...

  2. Cleft lip repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100010.htm Cleft lip repair - series—Normal anatomy To use the sharing ... abnormal opening in the middle of the upper lip. A cleft palate is an opening in the roof of ...

  3. Distribution of selected PCB congeners in the Babcock Street sewer district: a multimedia approach to identify PCB sources in combined sewer overflows (CSOs) discharging to the Buffalo River, New York.

    Science.gov (United States)

    Loganathan, B G; Irvine, K N; Kannan, K; Pragatheeswaran, V; Sajwan, K S

    1997-08-01

    To evaluate sources of PCBs in combined sewer overflows (CSOs) to the Buffalo River, New York, combined sewage, sanitary flow, atmospheric wet and dry depositions, and street dust samples were collected from the Babcock Street sewer district and analyzed. Total PCB concentrations (sum of the PCB congeners quantitated) in particulate and dissolved phases of sanitary flow were 101-269 ng g-1 dry weight and 50% of the total PCB load in street dust samples. PCB congener composition in the particulate phase of CSOs reflects the congener pattern of the street dusts. In this context, it can be suggested that the local contaminated street dusts are one of the potential sources of PCBs in CSOs, which is a source of PCBs to the Buffalo River.

  4. Grey Repairable System Analysis

    Institute of Scientific and Technical Information of China (English)

    Renkuan Guo; Charles Ernie Love

    2006-01-01

    In this paper, we systematically discuss the basic concepts of grey theory, particularly the grey differential equation and its mathematical foundation, which is essentially unknown in the reliability engineering community. Accordingly,we propose a small-sample based approach to estimate repair improvement effects by partitioning system stopping times into intrinsic functioning times and repair improvement times. An industrial data set is used for illustrative purposes in a stepwise manner.

  5. Sociology: Clean-energy conservatism

    Science.gov (United States)

    McCright, Aaron M.

    2017-03-01

    US conservatives receive a steady stream of anti-environmental messaging from Republican politicians. However, clean-energy conservatives sending strong counter-messages on energy issues could mobilize moderate conservatives to break away from the dominant right-wing defence of fossil fuels.

  6. Cleaning Validation of Fermentation Tanks

    DEFF Research Database (Denmark)

    Salo, Satu; Friis, Alan; Wirtanen, Gun

    2008-01-01

    Reliable test methods for checking cleanliness are needed to evaluate and validate the cleaning process of fermentation tanks. Pilot scale tanks were used to test the applicability of various methods for this purpose. The methods found to be suitable for validation of the clenlinees were visula...

  7. Partnership for a Clean Future

    Institute of Scientific and Technical Information of China (English)

    WANG HAIRONG

    2010-01-01

    @@ Having lived in China for almost three decades,Sabina Brady is a de facto China hand.Currently,she is the cxecutive director of the U.S.-China Energy Cooperation Program (ECP),a nonprofit organization that engages in market development and promotion of clean energy within the framework of China-U.S.bilateral government commitments on the environrnent and energy.

  8. Clean coal initiatives in Indiana

    Science.gov (United States)

    Bowen, B.H.; Irwin, M.W.; Sparrow, F.T.; Mastalerz, Maria; Yu, Z.; Kramer, R.A.

    2007-01-01

    Purpose - Indiana is listed among the top ten coal states in the USA and annually mines about 35 million short tons (million tons) of coal from the vast reserves of the US Midwest Illinois Coal Basin. The implementation and commercialization of clean coal technologies is important to the economy of the state and has a significant role in the state's energy plan for increasing the use of the state's natural resources. Coal is a substantial Indiana energy resource and also has stable and relatively low costs, compared with the increasing costs of other major fuels. This indigenous energy source enables the promotion of energy independence. The purpose of this paper is to outline the significance of clean coal projects for achieving this objective. Design/methodology/approach - The paper outlines the clean coal initiatives being taken in Indiana and the research carried out at the Indiana Center for Coal Technology Research. Findings - Clean coal power generation and coal for transportation fuels (coal-to-liquids - CTL) are two major topics being investigated in Indiana. Coking coal, data compilation of the bituminous coal qualities within the Indiana coal beds, reducing dependence on coal imports, and provision of an emissions free environment are important topics to state legislators. Originality/value - Lessons learnt from these projects will be of value to other states and countries.

  9. Wanted: Clean Coal Burning Technology

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    China is intent on developing clean coal burning technology, an objective it can achieve through installing desulfurization facilities at coal-burning power plants that will control SO2 emissions and environmental pollution. According to kuo Yi, deputy director general of the Department of Science and Technology of the State Environmental Protection Agency, China is a major coal-buming country:

  10. Teaming up for Clean Energy

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    On October 22, the China Institute of Strategy and Management and the U.S. Brookings Institution jointly held the China-U.S. Strategic Forum on Clean Energy Cooperation. At the opening session of the forum, Zheng Bijian, Chairman of the China Institute of Strategy and Management, gave a keynote speech. Edited excerpts follow:

  11. Laser cleaning on Roman coins

    Science.gov (United States)

    Drakaki, E.; Karydas, A. G.; Klinkenberg, B.; Kokkoris, M.; Serafetinides, A. A.; Stavrou, E.; Vlastou, R.; Zarkadas, C.

    Ancient metal objects react with moisture and environmental chemicals to form various corrosion products. Because of the unique character and high value of such objects, any cleaning procedure should guarantee minimum destructiveness. The most common treatment used is mechanical stripping, in which it is difficult to avoid surface damage when employed. Lasers are currently being tested for a wide range of conservation applications. Since they are highly controllable and can be selectively applied, lasers can be used to achieve more effective and safer cleaning of archaeological artifacts and protect their surface details. The basic criterion that motivated us to use lasers to clean Roman coins was the requirement of pulsed emission, in order to minimize heat-induced damages. In fact, the laser interaction with the coins has to be short enough, to produce a fast removal of the encrustation, avoiding heat conduction into the substrate. The cleaning effects of three lasers operating at different wavelengths, namely a TEA CO2 laser emitting at 10.6 μm, an Er:YAG laser at 2.94 μm, and a 2ω-Nd:YAG laser at 532 nm have been compared on corroded Romans coins and various atomic and nuclear techniques have also been applied to evaluate the efficiency of the applied procedure.

  12. Pollute first, clean up later?

    NARCIS (Netherlands)

    Azadi, Hossein; Verheijke, Gijs; Witlox, Frank

    2011-01-01

    There is a growing concern with regard to sustainability in emerging economies like China. The Chinese growth is characterized by a strategy which is known as "pollute first, clean up later". Here we show that based on this strategy, the pollution alarm can often be postponed by a tremendous economi

  13. Cleaning Validation of Fermentation Tanks

    DEFF Research Database (Denmark)

    Salo, Satu; Friis, Alan; Wirtanen, Gun

    2008-01-01

    Reliable test methods for checking cleanliness are needed to evaluate and validate the cleaning process of fermentation tanks. Pilot scale tanks were used to test the applicability of various methods for this purpose. The methods found to be suitable for validation of the clenlinees were visula o...

  14. Clean Energy Infrastructure Educational Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Hallinan, Kevin; Menart, James; Gilbert, Robert

    2012-08-31

    The Clean Energy Infrastructure Educational Initiative represents a collaborative effort by the University of Dayton, Wright State University and Sinclair Community College. This effort above all aimed to establish energy related programs at each of the universities while also providing outreach to the local, state-wide, and national communities. At the University of Dayton, the grant has aimed at: solidfying a newly created Master's program in Renewable and Clean Energy; helping to establish and staff a regional sustainability organization for SW Ohio. As well, as the prime grantee, the University of Dayton was responsible for insuring curricular sharing between WSU and the University of Dayton. Finally, the grant, through its support of graduate students, and through cooperation with the largest utilities in SW Ohio enabled a region-wide evaluation of over 10,000 commercial building buildings in order to identify the priority buildings in the region for energy reduction. In each, the grant has achieved success. The main focus of Wright State was to continue the development of graduate education in renewable and clean energy. Wright State has done this in a number of ways. First and foremost this was done by continuing the development of the new Renewable and Clean Energy Master's Degree program at Wright State . Development tasks included: continuing development of courses for the Renewable and Clean Energy Master's Degree, increasing the student enrollment, and increasing renewable and clean energy research work. The grant has enabled development and/or improvement of 7 courses. Collectively, the University of Dayton and WSU offer perhaps the most comprehensive list of courses in the renewable and clean energy area in the country. Because of this development, enrollment at WSU has increased from 4 students to 23. Secondly, the grant has helped to support student research aimed in the renewable and clean energy program. The grant helped to solidify

  15. Half saturation constants for nitrate and nitrite by in-sewer anoxic transformations of wastewater organic matter

    DEFF Research Database (Denmark)

    Abdul-Talib, Suhaimi; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes

    2001-01-01

     significant breakthrough and progress have been made in the study of the kinetics of microbial transformation in sewers under aerobic and under changing aerobic/anaerobic conditions. Fundamental knowledge on anoxic kinetics of wastewater is still lacking, so it is not now possible to apply...... an integrated approach to municipal wastewater treatment incorporating sewer networks as a bio-chemical reactor. This paper presents the results of studies on determining half saturation constants for nitrate, KNO3, and nitrite, KNO2, in raw wastewater. The average values of KNO3 and KNO2, determined from...... experiments conducted on 7 different wastewater samples were found to be 0.76 gNO3.N/m3 and 0.33 gNO2-N/m3 respectively....

  16. Calculation of Intercepted Volume of Sewer Overflows: a Model for Control of Nonpoint Pollution Sources in Urban Areas

    Institute of Scientific and Technical Information of China (English)

    S. C. Choi; D. I. Jung; C. H. Won; J. M. Rim

    2006-01-01

    The authors discovered large differences in the characteristics of overflows by the calculation of 1) intercepting volume of overflows for sewer systems using SWMM model which takes into consideration the runoff and pollutants from rainfalls and 2) the intercepted volume in the total flow at an investigation site. The intercepting rate at the investigation point of CSOs showed higher values than the SSDs. Based on the modeling of the receiving water quality after calculating the intercepting amount of overflows by considering the characteristics of outflows for a proper management of the overflow of sewer systems with rainfalls, it is clear that the BOD decreased by 82.9%-94.0% for the discharge after intercepting a specific amount of flows compared to the discharge from unprocessed overflows.

  17. Release of hydrogen sulfide in a sewer system under intermittent flow conditions: the Ericeira case study, in Portugal

    DEFF Research Database (Denmark)

    Matias, Natércia; Matos, Rita Ventura; Ferreira, Filipa

    2017-01-01

    The presence and fate of hydrogen sulfide in wastewater systems were studied in two stretches of an intercepting sewer system located in a coastal village, in Portugal. A range of hydraulic parameters were obtained and liquid and gas phase measurements were carried out, both continuously...... and through intensive sampling campaigns. Upstream, where flow rates were relatively low, dissolved sulfide concentrations around 12 mg S L1 and hydrogen sulfide gas concentrations above 250 ppm were observed, along with limited corrosion damage. It is believed this is due to the low relative humidity...... detected along the atmosphere of the studied sewer system. Downstream, gas concentrations were always below 40 ppm. Despite that, high signs of corrosion were detected, particularly in manholes with drop structures. It is thought that condensation of spray produced by the fall is the main cause...

  18. Benchmarks of Global Clean Energy Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Sandor, Debra [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chung, Donald [National Renewable Energy Lab. (NREL), Golden, CO (United States); Keyser, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mann, Margaret [National Renewable Energy Lab. (NREL), Golden, CO (United States); Engel-Cox, Jill [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-01-01

    The Clean Energy Manufacturing Analysis Center (CEMAC), sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), provides objective analysis and up-to-date data on global supply chains and manufacturing of clean energy technologies. Benchmarks of Global Clean Energy Manufacturing sheds light on several fundamental questions about the global clean technology manufacturing enterprise: How does clean energy technology manufacturing impact national economies? What are the economic opportunities across the manufacturing supply chain? What are the global dynamics of clean energy technology manufacturing?

  19. Evaluating rain gardens as a method to reduce the impact of sewer overflows in sources of drinking water.

    Science.gov (United States)

    Autixier, Laurène; Mailhot, Alain; Bolduc, Samuel; Madoux-Humery, Anne-Sophie; Galarneau, Martine; Prévost, Michèle; Dorner, Sarah

    2014-11-15

    The implications of climate change and changing precipitation patterns need to be investigated to evaluate mitigation measures for source water protection. Potential solutions need first to be evaluated under present climate conditions to determine their utility as climate change adaptation strategies. An urban drainage network receiving both stormwater and wastewater was studied to evaluate potential solutions to reduce the impact of combined sewer overflows (CSOs) in a drinking water source. A detailed hydraulic model was applied to the drainage basin to model the implementation of best management practices at a drainage basin scale. The model was calibrated and validated with field data of CSO flows for seven events from a survey conducted in 2009 and 2010. Rain gardens were evaluated for their reduction of volumes of water entering the drainage network and of CSOs. Scenarios with different levels of implementation were considered and evaluated. Of the total impervious area within the basin directly connected to the sewer system, a maximum of 21% could be alternately directed towards rain gardens. The runoff reductions for the entire catchment ranged from 12.7% to 19.4% depending on the event considered. The maximum discharged volume reduction ranged from 13% to 62% and the maximum peak flow rate reduction ranged from 7% to 56%. Of concern is that in-sewer sediment resuspension is an important process to consider with regard to the efficacy of best management practices aimed at reducing extreme loads and concentrations. Rain gardens were less effective for large events, which are of greater importance for drinking water sources. These practices could increase peak instantaneous loads as a result of greater in-sewer resuspension during large events. Multiple interventions would be required to achieve the objectives of reducing the number, total volumes and peak contaminant loads of overflows upstream of drinking water intakes.

  20. High prevalence of Leptospira spp. in sewer rats (Rattus norvegicus)

    DEFF Research Database (Denmark)

    Krøjgaard, L H; Villumsen, S; Markussen, M D K

    2009-01-01

    Earlier studies on the ecology of leptospirosis in temperate regions focused mainly on free-ranging rats in rural areas. Here we report on the occurrence of Leptospira spp. in Rattus norvegicus living in sewers in a suburban area in Copenhagen, Denmark. In 2006-2007, about 30 rats were captured i......, the urprisingly high level of infection calls for an increased public health concern. ...

  1. Determining the long-term effects of H₂S concentration, relative humidity and air temperature on concrete sewer corrosion.

    Science.gov (United States)

    Jiang, Guangming; Keller, Jurg; Bond, Philip L

    2014-11-15

    Many studies of sewer corrosion are performed in accelerated conditions that are not representing the actual corrosion processes. This study investigated the effects of various factors over 3.5 years under controlled conditions simulating the sewer environment. Concrete coupons prepared from precorroded sewers were exposed, both in the gas phase and partially submerged in wastewater, in laboratory controlled corrosion chambers. Over the 45 month exposure period, three environmental factors of H2S concentration, relative humidity and air temperature were controlled at different levels in the corrosion chambers. A total of 36 exposure conditions were investigated to determine the long term effects of these factors by regular retrieval of concrete coupons for detailed analysis of surface pH, corrosion layer sulfate levels and concrete loss. Corrosion rates were also determined for different exposure periods. It was found that the corrosion rate of both gas-phase and partially-submerged coupons was positively correlated with the H2S concentration in the gas phase. Relative humidity played also a role for the corrosion activity of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as the surfaces of these coupons were saturated due to capillary suction of sewage on the coupon surface. The effect of temperature on corrosion activity varied and possibly the acclimation of corrosion-inducing microbes to temperature mitigated effects of that factor. It was apparent that biological sulfide oxidation was not the limiting step of the overall corrosion process. These findings provide real insights into the long-term effects of these key environmental factors on the sewer corrosion processes.

  2. Experimental calibration and validation of sewer/surface flow exchange equations in steady and unsteady flow conditions

    Science.gov (United States)

    Rubinato, Matteo; Martins, Ricardo; Kesserwani, Georges; Leandro, Jorge; Djordjević, Slobodan; Shucksmith, James

    2017-09-01

    The linkage between sewer pipe flow and floodplain flow is recognised to induce an important source of uncertainty within two-dimensional (2D) urban flood models. This uncertainty is often attributed to the use of empirical hydraulic formulae (the one-dimensional (1D) weir and orifice steady flow equations) to achieve data-connectivity at the linking interface, which require the determination of discharge coefficients. Because of the paucity of high resolution localised data for this type of flows, the current understanding and quantification of a suitable range for those discharge coefficients is somewhat lacking. To fulfil this gap, this work presents the results acquired from an instrumented physical model designed to study the interaction between a pipe network flow and a floodplain flow. The full range of sewer-to-surface and surface-to-sewer flow conditions at the exchange zone are experimentally analysed in both steady and unsteady flow regimes. Steady state measured discharges are first analysed considering the relationship between the energy heads from the sewer flow and the floodplain flow; these results show that existing weir and orifice formulae are valid for describing the flow exchange for the present physical model, and yield new calibrated discharge coefficients for each of the flow conditions. The measured exchange discharges are also integrated (as a source term) within a 2D numerical flood model (a finite volume solver to the 2D Shallow Water Equations (SWE)), which is shown to reproduce the observed coefficients. This calibrated numerical model is then used to simulate a series of unsteady flow tests reproduced within the experimental facility. Results show that the numerical model overestimated the values of mean surcharge flow rate. This suggests the occurrence of additional head losses in unsteady conditions which are not currently accounted for within flood models calibrated in steady flow conditions.

  3. Evaluation of Ecotoxicological Risks Related to the Discharge of Combined Sewer Overflows (CSOs) in a Periurban River

    OpenAIRE

    Evens Emmanuel; Yves Perrodin; Ruth Angerville; Christine Bazin

    2013-01-01

    Discharges of Combined Sewer Overflows (CSOs) into periurban rivers present risks for the concerned aquatic ecosystems. In this work, a specific ecotoxicological risk assessment methodology has been developed as management tool to municipalities equipped with CSOs. This methodology comprises a detailed description of the spatio-temporal system involved, the choice of ecological targets to be preserved, and carrying out bioassays adapted to each compartment of the river receiving CSOs. Once fo...

  4. Field validation of a new low-cost method for determining occurrence and duration of combined sewer overflows.

    Science.gov (United States)

    Montserrat, A; Gutierrez, O; Poch, M; Corominas, Ll

    2013-10-01

    Combined sewer overflow (CSO) events produced in combined sewer systems (CSS) during wet weather conditions are a threat for the receiving water bodies. The large number of CSO structures normally present in a CSS makes that the monitoring of the complete CSO network in a simultaneous way would drastically increase the investment costs. In this paper, a new methodology is presented aiming to characterize the occurrence and duration of CSO events by means of low-cost temperature sensors. Hence, a large number of CSO structures can be simultaneously monitored and the system can be characterized as a whole. The method assumes temperature differences between the overflowing mix of wastewater and stormwater and the sewer gas phase, so the temperature shift produced during a rainfall episode is related to a CSO event occurrence. The method has been tested and validated in La Garriga CSS (Spain) where the temperature at 13 CSO weirs was monitored for a period of 1 year (57 rainfall episodes). For the whole set of CSO events, occurrence and duration were successfully determined in 80% of cases. Advantages, limitations and potential applications of the method are discussed at the end of the paper.

  5. Succession of sulfur-oxidizing bacteria in the microbial community on corroding concrete in sewer systems.

    Science.gov (United States)

    Okabe, Satoshi; Odagiri, Mitsunori; Ito, Tsukasa; Satoh, Hisashi

    2007-02-01

    Microbially induced concrete corrosion (MICC) in sewer systems has been a serious problem for a long time. A better understanding of the succession of microbial community members responsible for the production of sulfuric acid is essential for the efficient control of MICC. In this study, the succession of sulfur-oxidizing bacteria (SOB) in the bacterial community on corroding concrete in a sewer system in situ was investigated over 1 year by culture-independent 16S rRNA gene-based molecular techniques. Results revealed that at least six phylotypes of SOB species were involved in the MICC process, and the predominant SOB species shifted in the following order: Thiothrix sp., Thiobacillus plumbophilus, Thiomonas intermedia, Halothiobacillus neapolitanus, Acidiphilium acidophilum, and Acidithiobacillus thiooxidans. A. thiooxidans, a hyperacidophilic SOB, was the most dominant (accounting for 70% of EUB338-mixed probe-hybridized cells) in the heavily corroded concrete after 1 year. This succession of SOB species could be dependent on the pH of the concrete surface as well as on trophic properties (e.g., autotrophic or mixotrophic) and on the ability of the SOB to utilize different sulfur compounds (e.g., H2S, S0, and S2O3(2-)). In addition, diverse heterotrophic bacterial species (e.g., halo-tolerant, neutrophilic, and acidophilic bacteria) were associated with these SOB. The microbial succession of these microorganisms was involved in the colonization of the concrete and the production of sulfuric acid. Furthermore, the vertical distribution of microbial community members revealed that A. thiooxidans was the most dominant throughout the heavily corroded concrete (gypsum) layer and that A. thiooxidans was most abundant at the highest surface (1.5-mm) layer and decreased logarithmically with depth because of oxygen and H2S transport limitations. This suggested that the production of sulfuric acid by A. thiooxidans occurred mainly on the concrete surface and the

  6. Clean Cities Now Vol. 17, No. 1

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-05-24

    Biannual newsletter for the U.S. Department of Energy's Clean Cities initiative. The newsletter includes feature stories on advanced vehicle deployment, idle reduction, and articles on Clean Cities coalition successes across the country.

  7. Clean Cities Now Vol. 16.1

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-05-01

    Biannual newsletter for the U.S. Department of Energy's Clean Cities initiative. The newsletter includes feature stories on advanced vehicle deployment, idle reduction, and articles on Clean Cities coalition successes across the country.

  8. The MiniCLEAN Experiment

    Science.gov (United States)

    Wang, Jui-Jen (Ryan); Gold, Michael; Miniclean Collaboration

    2017-01-01

    The MiniCLEAN (Cryogenic Low-Energy Astrophysics with Noble liquid) dark matter experiment will exploit a single-phase liquid argon detector instrumented with 92 photomultiplier tubes placed in the cryogen with 4- π coverage of a 500 kg (150 kg) target (fiducial) mass. The detector design strategy emphasizes scalability to target masses of order 10 tons or more. It is designed also for a liquid neon target that allows for an independent verification of signal and background and a test of the expected dependence of the WIMP-nucleus interaction rate. For MiniCLEAN, PMT stability and calibration are essential. The Light-Emitting Diode (LED) based light injection system provide single photon for the calibration which can be performed in near real-time, providing a continuous monitor on the condition of the detector. This talk will summarize the status of detector and upcoming commissioning at SNOLAB in Sudbury, Canada.

  9. Detecting and Correcting Speech Repairs

    CERN Document Server

    Heeman, P A; Heeman, Peter; Allen, James

    1994-01-01

    Interactive spoken dialog provides many new challenges for spoken language systems. One of the most critical is the prevalence of speech repairs. This paper presents an algorithm that detects and corrects speech repairs based on finding the repair pattern. The repair pattern is built by finding word matches and word replacements, and identifying fragments and editing terms. Rather than using a set of prebuilt templates, we build the pattern on the fly. In a fair test, our method, when combined with a statistical model to filter possible repairs, was successful at detecting and correcting 80\\% of the repairs, without using prosodic information or a parser.

  10. Low cost, high tech seed cleaning

    Science.gov (United States)

    Robert P. Karrfalt

    2013-01-01

    Clean seeds are a great asset in native plant restoration. However, seed cleaning equipment is often too costly for many small operations. This paper introduces how several tools and materials intended for other purposes can be used directly or made into simple machines to clean seeds.

  11. Clean Energy Solutions Center Services (French Translation)

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    This is a French translation of the Clean Energy Solutions Center fact sheet. The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

  12. Clean Energy Solutions Center Services (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-04-01

    The Clean Energy Solutions Center (Solutions Center) helps governments, advisors and analysts create policies and programs that advance the deployment of clean energy technologies. The Solutions Center partners with international organizations to provide online training, expert assistance, and technical resources on clean energy policy.

  13. Air cleaning using regenerative silica gel wheel

    DEFF Research Database (Denmark)

    Fang, Lei

    2011-01-01

    This paper discussed the necessity of indoor air cleaning and the state of the art information on gas-phase air cleaning technology. The performance and problems of oxidation and sorption air cleaning technology were summarized and analysed based on the literature studies. Eventually, based on an...

  14. 7 CFR 51.606 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.606 Section 51.606 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Consumer Standards for Celery Stalks Definitions § 51.606 Clean. Clean means that the stalk is...

  15. 7 CFR 51.1553 - Fairly clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly clean. 51.1553 Section 51.1553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Potatoes 1 Definitions § 51.1553 Fairly clean. Fairly clean means that at least...

  16. 7 CFR 51.1581 - Fairly clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly clean. 51.1581 Section 51.1581 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Consumer Standards for Potatoes Definitions § 51.1581 Fairly clean. Fairly clean means that from...

  17. 7 CFR 51.1316 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.1316 Section 51.1316 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Winter Pears 1 Definitions § 51.1316 Clean. Clean means free from excessive dirt, dust,...

  18. 7 CFR 29.2256 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 29.2256 Section 29.2256 Agriculture Regulations... INSPECTION Standards Official Standard Grades for Virginia Fire-Cured Tobacco (u.s. Type 21) § 29.2256 Clean. Tobacco is described as clean when it contains only a normal amount of sand or soil particles....

  19. 7 CFR 51.1552 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.1552 Section 51.1552 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Potatoes 1 Definitions § 51.1552 Clean. Clean means that at least 90 percent of...

  20. 7 CFR 29.3507 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 29.3507 Section 29.3507 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3507 Clean. Tobacco is described as clean when it contains only a normal amount of...

  1. 7 CFR 51.2288 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.2288 Section 51.2288 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2288 Clean. Clean means that...

  2. 7 CFR 51.1867 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.1867 Section 51.1867 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Fresh Tomatoes 1 Definitions § 51.1867 Clean. Clean means that the tomato is practically...

  3. 7 CFR 51.2965 - Fairly clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly clean. 51.2965 Section 51.2965 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Walnuts in the Shell Definitions § 51.2965 Fairly clean. Fairly clean means...

  4. 7 CFR 51.2654 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.2654 Section 51.2654 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades for Sweet Cherries 1 Definitions § 51.2654 Clean. Clean means that the cherries...

  5. 7 CFR 51.2083 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.2083 Section 51.2083 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Almonds in the Shell Definitions § 51.2083 Clean. Clean means that the shell...

  6. 7 CFR 29.1004 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 29.1004 Section 29.1004 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1004 Clean. Tobacco is described as clean when it contains only a normal amount of...

  7. 7 CFR 51.2118 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.2118 Section 51.2118 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Shelled Almonds Definitions § 51.2118 Clean. Clean means that the kernel...

  8. 7 CFR 29.3009 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 29.3009 Section 29.3009 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Clean. Tobacco is described as clean when it contains only a normal amount of sand or soil...

  9. 7 CFR 51.3061 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.3061 Section 51.3061 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Florida Avocados Definitions § 51.3061 Clean. Clean means that the avocado is practically...

  10. 7 CFR 51.1275 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.1275 Section 51.1275 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Summer and Fall Pears 1 Definitions § 51.1275 Clean. Clean means free from excessive...

  11. 7 CFR 51.570 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.570 Section 51.570 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Celery Definitions § 51.570 Clean. Clean means that the stalk is practically free from dirt...

  12. 48 CFR 36.512 - Cleaning up.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Cleaning up. 36.512... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.512 Cleaning up. The contracting officer shall insert the clause at 52.236-12, Cleaning Up, in solicitations and contracts when a...

  13. Clean Energy Manufacturing Analysis Center (CEMAC)

    Energy Technology Data Exchange (ETDEWEB)

    2015-12-01

    The U.S. Department of Energy's Clean Energy Manufacturing Analysis Center (CEMAC) provides objective analysis and up-to-date data on global supply chains and manufacturing of clean energy technologies. Policymakers and industry leaders seek CEMAC insights to inform choices to promote economic growth and the transition to a clean energy economy.

  14. Clean Cities Now, Vol. 18, No. 2

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-01-19

    This is version 18.2 of Clean Cities Now, the official biannual newsletter of the Clean Cities program. Clean Cities is an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

  15. Clean Energy Solutions Center Services (Arabic Translation)

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    This is an Arabic translation of the Clean Energy Solutions Center fact sheet. The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

  16. Clean Energy Solutions Center Services (Vietnamese Translation)

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    This is a Vietnamese translation of the Clean Energy Solutions Center fact sheet. The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

  17. Clean Energy Solutions Center Services (Chinese Translation)

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    This is a Mandarin translation of the Clean Energy Solutions Center fact sheet. The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

  18. 7 CFR 29.6007 - Clean.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 29.6007 Section 29.6007 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6007 Clean. Tobacco is described as clean when it contains only...

  19. Clean Energy Solutions Center Services (Portuguese Translation)

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    This is a Portuguese translation of the Clean Energy Solutions Center Services fact sheet. The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

  20. Clean Air Act. Revision 5

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-15

    This Reference Book contains a current copy of the Clean Air Act, as amended, and those regulations that implement the statute and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. This Reference Book has been completely revised and is current through February 15, 1994.

  1. Battery Technology Stores Clean Energy

    Science.gov (United States)

    2008-01-01

    Headquartered in Fremont, California, Deeya Energy Inc. is now bringing its flow batteries to commercial customers around the world after working with former Marshall Space Flight Center scientist, Lawrence Thaller. Deeya's liquid-cell batteries have higher power capability than Thaller's original design, are less expensive than lead-acid batteries, are a clean energy alternative, and are 10 to 20 times less expensive than nickel-metal hydride batteries, lithium-ion batteries, and fuel cell options.

  2. Waterless Clothes-Cleaning Machine

    Science.gov (United States)

    Johnson, Glenn; Ganske, Shane

    2013-01-01

    A waterless clothes-cleaning machine has been developed that removes loose particulates and deodorizes dirty laundry with regenerative chemical processes to make the clothes more comfortable to wear and have a fresher smell. This system was initially developed for use in zero-g, but could be altered for 1-g environments where water or other re sources are scarce. Some of these processes include, but are not limited to, airflow, filtration, ozone generation, heat, ultraviolet light, and photocatalytic titanium oxide.

  3. 'How To' Clean Room Video

    Science.gov (United States)

    McCarty, Kaley Corinne

    2013-01-01

    One of the projects that I am completing this summer is a Launch Services Program intern 'How to' set up a clean room informational video. The purpose of this video is to go along with a clean room kit that can be checked out by employees at the Kennedy Space Center and to be taken to classrooms to help educate students and intrigue them about NASA. The video will include 'how to' set up and operate a clean room at NASA. This is a group project so we will be acting as a team and contributing our own input and ideas. We will include various activities for children in classrooms to complete, while learning and having fun. Activities that we will explain and film include: helping children understand the proper way to wear a bunny suit, a brief background on cleanrooms, and the importance of maintaining the cleanliness of a space craft. This project will be shown to LSP management and co-workers; we will be presenting the video once it is completed.

  4. Small Engine Repair Modules (Workbook) = Reparacion de Motores Pequenos (Guia de Trabajo)

    Science.gov (United States)

    New York State Dept. of Correctional Services, Albany.

    This package contains an English-Language set of task procedure sheets dealing with small-engine repair and a Spanish translation of the same material. Addressed in the individual sections of the manual are the following aspects of engine tune-up, reconditioning, and troubleshooting: servicing air cleaners; cleaning gas tanks, fuel lines, and fuel…

  5. Small Engine Repair Modules (Workbook) = Reparacion de Motores Pequenos (Guia de Trabajo)

    Science.gov (United States)

    New York State Dept. of Correctional Services, Albany.

    This package contains an English-Language set of task procedure sheets dealing with small-engine repair and a Spanish translation of the same material. Addressed in the individual sections of the manual are the following aspects of engine tune-up, reconditioning, and troubleshooting: servicing air cleaners; cleaning gas tanks, fuel lines, and fuel…

  6. A study of surface optical properties for characterizing the cleaning process of paintings

    Science.gov (United States)

    Fontana, R.; Barucci, M.; Pampaloni, E.; Pezzati, L.; Daffara, C.

    2013-05-01

    "Cleaning" is a process of carefully identifying the cause of any deterioration or discolouration and then removing or treating these layers. The skill of the restorer is not only to understand the techniques and media used by the artist, but also to recognize what beauty lies beneath the veils of many years of neglect or adverse conditions. Surface cleaning is then one of the most important and sometimes controversial stages of the conservation process: it is an irreversible process that generally results in substantial physical changes of the object surface, raising thus a series of questions regarding aesthetics, the potential loss of historical information, and the ability to control the cleaning process adequately. Decisions have to be made regarding partial or complete removal of varnish: technical considerations include selection of a method that allows a great deal of control in the cleaning process, so that undesired layers can be removed without damaging the underlying ones by means of traditional cleaning methods, including mechanical or chemical removal. In this work we present a study of the optical properties of painting surfaces for the characterization of the cleaning process. Analyses were carried out by means of laser micro-profilometry and confocal microscopy. Measurements were carried out on a few paintings which are under repair at the Opificio delle Pietre Dure in Florence. Selected areas were surveyed with the two above mentioned techniques and results were correlated.

  7. Clean

    Institute of Scientific and Technical Information of China (English)

    何伟文

    2005-01-01

    Core competitiveness is a notion familiar to most managers with an MBA degree, These days, this is what is taught at renowned business schools and colleges. And in the real world,large and small enterprises are increasingly following this course of action, To concentrate on one or two single lines of business in most cases makes sense and boosts profit, There are, however,

  8. Combining a Novel Computer Vision Sensor with a Cleaning Robot to Achieve Autonomous Pig House Cleaning

    DEFF Research Database (Denmark)

    Andersen, Nils Axel; Braithwaite, Ian David; Blanke, Mogens

    2005-01-01

    Cleaning of livestock buildings is the single most health-threatening task in the agricultural industry and a transition to robot-based cleaning would be instrumental to improving working conditions for employees. Present cleaning robots fall short on cleanness quality, as they cannot perform...

  9. Chemical disinfection of combined sewer overflow waters using performic acid or peracetic acids.

    Science.gov (United States)

    Chhetri, Ravi Kumar; Thornberg, Dines; Berner, Jesper; Gramstad, Robin; Öjstedt, Ulrik; Sharma, Anitha Kumari; Andersen, Henrik Rasmus

    2014-08-15

    We investigated the possibility of applying performic acid (PFA) and peracetic acid (PAA) for disinfection of combined sewer overflow (CSO) in existing CSO management infrastructures. The disinfection power of PFA and PAA towards Escherichia coli (E. coli) and Enterococcus was studied in batch-scale and pre-field experiments. In the batch-scale experiment, 2.5 mg L(-1) PAA removed approximately 4 log unit of E. coli and Enterococcus from CSO with a 360 min contact time. The removal of E. coli and Enterococcus from CSO was always around or above 3 log units using 2-4 mg L(-1) PFA; with a 20 min contact time in both batch-scale and pre-field experiments. There was no toxicological effect measured by Vibrio fischeri when CSO was disinfected with PFA; a slight toxic effect was observed on CSO disinfected with PAA. When the design for PFA based disinfection was applied to CSO collected from an authentic event, the disinfection efficiencies were confirmed and degradation rates were slightly higher than predicted in simulated CSO.

  10. Assessment of sewer source contamination of drinking water wells using tracers and human enteric viruses.

    Science.gov (United States)

    Hunt, Randall J; Borchardt, Mark A; Richards, Kevin D; Spencer, Susan K

    2010-10-15

    This study investigated the source, transport, and occurrence of human enteric viruses in municipal well water, focusing on sanitary sewer sources. A total of 33 wells from 14 communities were sampled once for wastewater tracers and viruses. Wastewater tracers were detected in four of these wells, and five wells were virus- positive by qRT-PCR. These results, along with exclusion of wells with surface water sources, were used to select three wells for additional investigation. Viruses and wastewater tracers were found in the groundwater at all sites. Some wastewater tracers, such as ionic detergents, flame retardants, and cholesterol, were considered unambiguous evidence of wastewater. Sampling at any given time may not show concurrent virus and tracer presence; however, given sufficient sampling over time, a relation between wastewater tracers and virus occurrence was identified. Presence of infectious viruses at the wellhead demonstrates that high-capacity pumping induced sufficiently short travel times for the transport of infectious viruses. Therefore, drinking-water wells are vulnerable to contaminants that travel along fast groundwater flowpaths even if they contribute a small amount of virus-laden water to the well. These results suggest that vulnerability assessments require characterization of "low yield-fast transport" in addition to traditional "high yield-slow transport", pathways.

  11. A forward osmosis-membrane distillation hybrid process for direct sewer mining: system performance and limitations.

    Science.gov (United States)

    Xie, Ming; Nghiem, Long D; Price, William E; Elimelech, Menachem

    2013-01-01

    This study demonstrates the robustness and treatment capacity of a forward osmosis (FO)-membrane distillation (MD) hybrid system for small-scale decentralized sewer mining. A stable water flux was realized using a laboratory-scale FO-MD hybrid system operating continuously with raw sewage as the feed at water recovery up to 80%. The hybrid system also showed an excellent capacity for the removal of trace organic contaminants (TrOCs), with removal rates ranging from 91 to 98%. The results suggest that TrOC transport through the FO membrane is governed by "solute-membrane" interaction, whereas that through the MD membrane is strongly correlated to TrOC volatility. Concentrations of organic matter and TrOCs in the draw solution increased substantially as the water recovery increased. This accumulation of some contaminants in the draw solution is attributed to the difference in their rejection by the FO and MD systems. We demonstrate that granular activated carbon adsorption or ultraviolet oxidation could be used to prevent contaminant accumulation in the draw solution, resulting in near complete rejection (>99.5%) of TrOCs.

  12. Production of durable and cost effective sewer pipes using petroleum and industrial waste by-products

    Directory of Open Access Journals (Sweden)

    El Gamal Maisa

    2017-01-01

    Full Text Available The Arabian Gulf environment has an adverse impact on concrete structures because of the high ambient temperature, humidity, salt contaminated dust, sea water and underground salts. As an innovative solution, reinforced modified sulfur concrete (MSC pipes are recognized as a durable and economical solution for deterioration of pipelines. This work describes the manufacture and characterization of new MSC based on a cost effective sulfur modification process. Bitumen, a by-product from crude oil refining process was used to modify elemental sulfur and enhance its physical, mechanical properties, and mostly to increase its corrosive resistivity. The study has focused on optimizing the proportions of an offered MSC mixes that are composed of modified sulfur (MS as a binder, crushed sand, dune sand and ladle furnace (LF slag as aggregates, and ground granulated blast furnace slag (GGFBS as a filler. To maximize the physical and mechanical properties of MSC sewer pipes, different mixtures were prepared and investigated. The optimum mix of MSC has a maximum compressive strength of 64 MPa, maximum splitting tensile strength of 4.5 MPa, maximum flexural strength of 21 MP, with a high corrosion resistance in acidic and salty environments.

  13. The evaluation of rainfall influence on combined sewer overflows characteristics: the Berlin case study.

    Science.gov (United States)

    Sandoval, S; Torres, A; Pawlowsky-Reusing, E; Riechel, M; Caradot, N

    2013-01-01

    The present study aims to explore the relationship between rainfall variables and water quality/quantity characteristics of combined sewer overflows (CSOs), by the use of multivariate statistical methods and online measurements at a principal CSO outlet in Berlin (Germany). Canonical correlation results showed that the maximum and average rainfall intensities are the most influential variables to describe CSO water quantity and pollutant loads whereas the duration of the rainfall event and the rain depth seem to be the most influential variables to describe CSO pollutant concentrations. The analysis of partial least squares (PLS) regression models confirms the findings of the canonical correlation and highlights three main influences of rainfall on CSO characteristics: (i) CSO water quantity characteristics are mainly influenced by the maximal rainfall intensities, (ii) CSO pollutant concentrations were found to be mostly associated with duration of the rainfall and (iii) pollutant loads seemed to be principally influenced by dry weather duration before the rainfall event. The prediction quality of PLS models is rather low (R² < 0.6) but results can be useful to explore qualitatively the influence of rainfall on CSO characteristics.

  14. Micropollutants in stormwater runoff and combined sewer overflow in the Copenhagen area, Denmark.

    Science.gov (United States)

    Birch, H; Mikkelsen, P S; Jensen, J K; Lützhøft, H-C Holten

    2011-01-01

    Stormwater runoff contains a broad range of micropollutants. In Europe a number of these substances are regulated through the Water Framework Directive, which establishes Environmental Quality Standards (EQSs) for surface waters. Knowledge about discharge of these substances through stormwater runoff and combined sewer overflows (CSOs) is essential to ensure compliance with the EQSs. Results from a screening campaign including more than 50 substances at four stormwater discharge locations and one CSO in Copenhagen are reported here. Heavy metal concentrations were detected at levels similar to earlier findings, e.g., with copper found at concentrations up to 13 times greater than the Danish standard for surface waters. The concentration of polyaromatic hydrocarbons (PAHs) exceeded the EQSs by factors up to 500 times for stormwater and 2,000 times for the CSO. Glyphosate was found in all samples whilst diuron, isoproturon, terbutylazine and MCPA were found only in some of the samples. Diethylhexylphthalate (DEHP) was also found at all five locations in concentrations exceeding the EQS. The results give a valuable background for designing further monitoring programmes focusing on the chemical status of surface waters in urban areas.

  15. Management of combined sewer overflows based on observations from the urbanized Liguori catchment of Cosenza, Italy.

    Science.gov (United States)

    Piro, P; Carbone, M; Garofalo, G; Sansalone, J J

    2010-01-01

    This paper examines an urbanized catchment in Cosenza, Italy where an off-line basin intercepting CSOs was studied to illustrate reduction in CSO discharges to the Crati River. While the hydrologic transport of pollutant mass is never known a-priori and can be flow-limited, the volumetric requirements of the basin were modeled based on the classic assumption that wet weather flows transport urban and sewer loads in a mass-limited (first-flush) delivery. The volumetric capacity of the basin was varied from 10 to 50 m(3)/ha. Operational basin control was simulated with historical datasets from the Liguori catchment, event-based loading data, and continuous simulation modelling with SWMM. Utilizing data from the catchment, the SWMM simulations were conducted considering the storage basin with or without sedimentation treatment. Results illustrate the potential benefits of the off-line operation for the system with respect to the volume and mass reduction of CSOs into the Crati River. Results demonstrate the importance of particle size distribution (PSD) as an index of basin efficiency, coupled with analysis of the hydrodynamic response of the basin. The basin model attenuated influent PSDs, separating the coarser fraction of the PSD, and reduced the load of influent particulate matter (PM).

  16. An elutriation apparatus for assessing settleability of combined sewer overflows (CSOs).

    Science.gov (United States)

    Marsalek, J; Krishnappan, B G; Exall, K; Rochfort, Q; Stephens, R P

    2006-01-01

    An elutriation apparatus was proposed for testing the settleability of combined sewer outflows (CSOs) and applied to 12 CSO samples. In this apparatus, solids settling is measured under dynamic conditions created by flow through a series of settling chambers of varying diameters and upward flow velocities. Such a procedure reproduces better turbulent settling in CSO tanks than the conventional settling columns, and facilitates testing coagulant additions under dynamic conditions. Among the limitations, one could name the relatively large size of the apparatus and samples (60 L), and inadequate handling of floatables. Settleability results obtained for the elutriation apparatus and a conventional settling column indicate large inter-event variation in CSO settleability. Under such circumstances, settling tanks need to be designed for "average" conditions and, within some limits, the differences in test results produced by various settleability testing apparatuses and procedures may be acceptable. Further development of the elutriation apparatus is under way, focusing on reducing flow velocities in the tubing connecting settling chambers and reducing the number of settling chambers employed. The first measure would reduce the risk of floc breakage in the connecting tubing and the second one would reduce the required sample size.

  17. Modelling of E. coli distribution in coastal areas subjected to combined sewer overflows.

    Science.gov (United States)

    De Marchis, Mauro; Freni, Gabriele; Napoli, Enrico

    2013-01-01

    Rivers, lakes and the sea were the natural receivers of raw urban waste and storm waters for a long time but the low sustainability of such practice, the increase of population and a renewed environmental sensibility increased researcher interest in the analysis and mitigation of the impact of urban waters on receiving water bodies (RWB). In Europe, the integrated modelling of drainage systems and RWB has been promoted as a promising approach for implementing the Water Framework Directive. A particular interest is given to the fate of pathogens and especially of Escherichia coli, in all the cases in which an interaction between population and the RWB is foreseen. The present paper aims to propose an integrated water quality model involving the analysis of several sewer systems (SS) discharging their polluting overflows on the coast in a sensitive marine environment. From a modelling point of view, the proposed application integrated one-dimensional drainage system models with a complex three-dimensional model analysing the propagation in space and time of E. coli in the coastal marine area. The integrated approach was tested in a real case study (the Acicastello bay in Italy) where data were available both for SS model and for RWB propagation model calibration. The analysis shows a good agreement between the model and monitored data. The integrated model was demonstrated to be a valuable tool for investigating the pollutant propagation and to highlight the most impacted areas.

  18. Combined Sewer Overflows as a Source of Hormones to Surface Water

    Science.gov (United States)

    Phillips, P.; Chalmers, A.; Gray, J. L.; Foreman, W.; Kolpin, D. W.; Wall, G.; Esposito, K.

    2009-12-01

    Some sources of hormones to surface water, such as wastewater-treatment-plant (WWTP) effluent, have been well documented, but other sources, particularly wet-weather discharges from combined-sewer-overflows (CSOs), are not well characterized. Flow-weighted composite samples of secondarily treated WWTP effluent and untreated sewage discharges from WWTP inflows and CSO discharges were collected during 12 storms and 6 non-storm conditions from November 2007-December 2008 at the main Burlington Vermont WWTP. Concentrations of many androgens and estrogens were highest in samples from untreated sewage, and lower in samples from treated sewage. For example, concentrations of estriol in CSO samples ranged from 5 to over 100 ng/L (nanograms per liter), but were generally less than 1 ng/L in treated sewage. Many androgens were detected in CSO discharge samples in concentrations ranging from 1 to over 1000 ng/L, but were not detected above 1 ng/L in treated samples. For many of the hormones, including androgens and estriol, CSO discharges comprised over half of the total load discharged by the WWTP, even though annual CSO discharge is less than 10% of the treated plant discharge. These results indicate that untreated discharges during CSO events can be a major source of some hormones and other wastewater compounds to the environment.

  19. Model evaluation of faecal contamination in coastal areas affected by urban rivers receiving combined sewer overflows.

    Science.gov (United States)

    Shibata, T; Kojima, K; Lee, S A; Furumai, H

    2014-01-01

    Odaiba seaside park is one of the most popular waterfronts in Tokyo Bay, but is easily affected by wet weather pollutant loads through combined sewer overflows (CSOs). The monitoring data of Escherichia coli clearly showed high faecal contamination after a rainfall event on 9-11 November 2007. We estimated the amounts of discharge volume and E. coli pollutant loads of urban rivers receiving CSO from rainfall chambers as well as pumping stations and primary effluent discharge. The result suggested that Sumida River and Meguro River were more influential to the Odaiba coastal area than other sources including the nearest wastewater treatment plant. Subsequently, we simulated the dynamic behaviour of E. coli by a three-dimensional (3D) hydro-dynamic and water quality model. The model simulation reproduced that E. coli concentration after the rainfall event increased rapidly at first and later gradually decreased. The simulations with and without inflow pollutant loads from urban rivers suggested that the E. coli concentration can be influenced by the Meguro River just after the rainfall event and Sumida River about 1 week later. From the spatial and temporal distribution of surface E. coli concentration, after at least 6 days from the rainfall event, high faecal contamination spread to the whole of the coastal area.

  20. London Tideway Tunnels: tackling London's Victorian legacy of combined sewer overflows.

    Science.gov (United States)

    Thomas, G B; Crawford, D

    2011-01-01

    It takes a few millimetres of rainfall to cause the 34 most polluting combined sewer overflows (CSOs) to discharge into the River Thames. Currently, in a typical year, spillages to the tidal reaches of the River Thames occur about 60 times, with an estimated spill volume of 39 million cubic metres. Both the UK Government and the European Union have determined that the CSO discharges have an adverse environmental impact on fish species, introduce unacceptable aesthetics and elevate the health risks for recreational users of the Thames, with a frequency of discharge which is in breach of the Urban Wastewater Treatment Directive. Studies have established that the environmental objectives can be fully met on the most cost-effective basis by completing both quality improvements to treatment works and by the provision of a storage and transfer tunnel to intercept unsatisfactory CSOs. Extensive modelling has been undertaken to develop an optimised solution. In parallel with the design development a rigorous and comprehensive site selection methodology has been established to select sites and consult stakeholders and the public on the preferred sites and scheme, with the first stage of public consultation planned for later in 2010. The London Tideway Tunnels are an essential part of the delivery of improvements to the water quality of the tidal River Thames, and this ambitious, historic scheme represents a vital strategic investment in London's infrastructure.