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1

Biogas Production and Utilization Potential of Wastewater Treatment Sludge  

Microsoft Academic Search

Municipal wastewater treatment plants generate sludge as a by-product of the physical, chemical and biological processes used in the treatment of wastewater. Generally, this sludge must be subject to some form of treatment in order to alter its character. By using anaerobic digestion in the treatment of wastewater sludge, methane gas is produced and it is known as biogas. It

A. Berktay; B. Nas

2007-01-01

2

Textile wastewater treatment: aerobic granular sludge vs activated sludge systems.  

PubMed

Textile effluents are characterised by high content of recalcitrant compounds and are often discharged (together with municipal wastewater to increase their treatability) into centralized wastewater treatment plants with a complex treatment scheme. This paper reports the results achieved adopting a granular sludge system (sequencing batch biofilter granular reactor - SBBGR) to treat mixed municipal-textile wastewater. Thanks to high average removals in SBBGR (82.1% chemical oxygen demand, 94.7% total suspended solids, 87.5% total Kjeldahl nitrogen, 77.1% surfactants), the Italian limits for discharge into a water receiver can be complied with the biological stage alone. The comparison with the performance of the centralized plant treating the same wastewater has showed that SBBGR system is able to produce an effluent of comparable quality with a simpler treatment scheme, a much lower hydraulic residence time (11 h against 30 h) and a lower sludge production. PMID:24583525

Lotito, Adriana Maria; De Sanctis, Marco; Di Iaconi, Claudio; Bergna, Giovanni

2014-05-01

3

40 CFR 721.10667 - Slimes and sludges, aluminum and iron casting, wastewater treatment, solid waste.  

Code of Federal Regulations, 2013 CFR

...false Slimes and sludges, aluminum and iron casting, wastewater treatment, solid...10667 Slimes and sludges, aluminum and iron casting, wastewater treatment, solid...generically as slimes and sludges, aluminum and iron casting, wastewater treatment,...

2013-07-01

4

Handling, Treatment and Disposal of Wastewater Sludge.  

National Technical Information Service (NTIS)

Contents: Policy on municipal sludges; Sludge incineration systems for purification and resource recovery; Management of oil sludge from a refinery waste water treatment plant; Modern state and principal trends in technology development for Washington slu...

1975-01-01

5

Munitions Wastewater Treatment in Semicontinuous Activated Sludge Treatment Systems.  

National Technical Information Service (NTIS)

A bench-scale study for the treatment of munitions wastewater was conducted in a semicontinuous activated sludge treatment system over a period of 30 months. This work effort addressed the suitability of such systems for the treatment of munitions wastewa...

B. A. Bell W. D. Burrows

1984-01-01

6

DESIGN HANDBOOK FOR AUTOMATION OF ACTIVATED SLUDGE WASTEWATER TREATMENT PLANTS  

EPA Science Inventory

This report is a systems engineering handbook for the automation of activated sludge wastewater treatment processes. Process control theory and application are discussed to acquaint the reader with terminology and fundamentals. Successful unit process control strategies currently...

7

Treatment of Textile Wastewater by Activated Sludge and Alum Coagulation.  

National Technical Information Service (NTIS)

The report gives results of a study of the treatment of wastewater, from a textile mill producing synthetic knit fabric for the apparel and automotive markets, with a system combining biological (activated sludge) and chemical (alum coagulation) processes...

T. L. Rinker

1975-01-01

8

Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant  

PubMed Central

Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm). The effects of changes in dissolved oxygen (DO) concentration up to 3 mg/L (run 1) and up to 6 mg/L (run 2) were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. The average sludge reductions were obtained as 32% (run 1) and 33% (run 2) in worm reactor and 16% (run 1) and 12% (run 2) in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blank conditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing.

2012-01-01

9

Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant.  

PubMed

Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm). The effects of changes in dissolved oxygen (DO) concentration up to 3 mg/L (run 1) and up to 6 mg/L (run 2) were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. The average sludge reductions were obtained as 32% (run 1) and 33% (run 2) in worm reactor and 16% (run 1) and 12% (run 2) in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blank conditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing. PMID:23369451

Basim, Yalda; Farzadkia, Mahdi; Jaafarzadeh, Nematollah; Hendrickx, Tim

2012-01-01

10

Effects of Alum Water Treatment Sludge on Domestic Wastewater Sludges.  

National Technical Information Service (NTIS)

Research on the effects of alum sludge generated by water treatment plants on the properties of domestic waste water sludges is reported. Phase I of the three phase investigation was concerned with the effects of raw sewage containing alum sludge on an ac...

M. E. Burman

1975-01-01

11

Activated Sludge. Bio-Disc Treatment of Distillery Wastewater.  

National Technical Information Service (NTIS)

Plant scale evaluation of activated sludge and Bio-Disc treatment of distillery wastewater has been conducted over a period of more than one year at Pekin, Illinois. The activated sludge process consistently provided in excess of 90 percent removal of BOD...

J. L. Thomas L. G. Koehrsen

1974-01-01

12

Minimization of excess sludge production for biological wastewater treatment.  

PubMed

Excess sludge treatment and disposal currently represents a rising challenge for wastewater treatment plants (WWTPs) due to economic, environmental and regulation factors. There is therefore considerable impetus to explore and develop strategies and technologies for reducing excess sludge production in biological wastewater treatment processes. This paper reviews current strategies for reducing sludge production based on these mechanisms: lysis-cryptic growth, uncoupling metabolism, maintenance metabolism, and predation on bacteria. The strategies for sludge reduction should be evaluated and chosen for practical application using costs analysis and assessment of environmental impact. High costs still limit technologies of sludge ozonation-cryptic growth and membrane bioreactor from spreading application in full-scale WWTPs. Bioacclimation and harmful to environment are major bottlenecks for chemical uncoupler in practical application. Sludge reduction induced by oligochaetes may present a cost-effective way for WWTPs if unstable worm growth is solved. Employing any strategy for reducing sludge production may have an impact on microbial community in biological wastewater treatment processes. This impact may influence the sludge characteristics and the quality of effluent. PMID:14511716

Wei, Yuansong; Van Houten, Renze T; Borger, Arjan R; Eikelboom, Dick H; Fan, Yaobo

2003-11-01

13

Livestock wastewater treatment using aerobic granular sludge.  

PubMed

The present study demonstrated that aerobic granular sludge is capable of treating livestock wastewater from a cattle farm in a sequencing batch reactor (SBR) without the presence of support material. A lab scale SBR was operated for 80 d using 4 h cycle time with an organic loading rate (OLR) of 9 kg COD m(-3) d(-1). Results showed that the aerobic granules were growing from 0.1 to 4.1 mm towards the end of the experimental period. The sludge volume index (SVI) was 42 ml g(-1) while the biomass concentration in the reactor grew up to 10.3 g L(-1) represent excellent biomass separation and good settling ability of the granules. During this period, maximum COD, TN and TP removal efficiencies (74%, 73% and 70%, respectively) were observed in the SBR system, confirming high microbial activity in the SBR system. PMID:23453799

Othman, Inawati; Anuar, Aznah Nor; Ujang, Zaini; Rosman, Noor Hasyimah; Harun, Hasnida; Chelliapan, Shreeshivadasan

2013-04-01

14

Biological sludge solubilisation for reduction of excess sludge production in wastewater treatment process.  

PubMed

A novel sludge disintegration system (JFE-SD system) was developed for the reduction of excess sludge production in wastewater treatment plants. Chemical and biological treatments were applied to disintegrate excess sludge. At the first step, to enhance biological disintegration, the sludge was pretreated with alkali. At the second step, the sludge was disintegrated by biological treatment. Many kinds of sludge degrading microorganisms integrated the sludge. The efficiency of the new sludge disintegration system was confirmed in a full-scale experiment. The JFE-SD system reduced excess sludge production by approximately 50% during the experimental period. The quality of effluent was kept at quite a good level. Economic analysis revealed that this system could significantly decrease the excess sludge treatment cost. PMID:17087369

Yamaguchi, T; Yao, Y; Kihara, Y

2006-01-01

15

Anaerobic Granulation in Expanded Granular Sludge Bed (EGSB) Reactor Seeded with Digestion Sludge for Treatment of Actual Coking Wastewater  

Microsoft Academic Search

To obtain the rapid anaerobic granulation in expanded granular sludge bed (EGSB) reactor seeded with digestion sludge for treatment of actual coking wastewater, the rapid granulation using brewery wastewater and the quickly acclimation using coking wastewater of the EGSB reactor seeded with municipal digestion sludge and little granules were studied in this paper. The results indicated that the EGSB reactor

Chunjuan Dong; Fei An

2011-01-01

16

Wastewater cleanup: Put activated-sludge treatment to work  

SciTech Connect

Strict wastewater treatment and discharge limits continue to challenge wastewater treatment systems. For industrial wastewater, the selected system must not only meet regulatory requirements, but must also be flexible enough to handle the variations in volume, flowrate and pollutant load that typify industrial effluent streams. At existing industrial sites, the selection of a wastewater treatment system is also impacted by constraints, such as limited space or the desire to minimize downtime or process interruptions. Meanwhile, for municipalities, wastewater treatment requirements are often made or complicated by the need to add a disinfection step to destroy waterborne pathogens in the discharge stream. Biological treatment processes, based on the use of activated sludge, have long been used to degrade organic contaminants in municipal and industrial wastewater. For years, the sequencing batch reactor (SBR) has been used to treat wastewater using activated sludge. However, in recent years, the variable depth reactor (VDR) has emerged as an alternative system, by addressing some of the shortcomings of the SBR.

Scroggins, D. [Pollution Control, Inc., Florence, KY (United States); Deiters, S. [Diffused Gas Technologies, Inc., Cincinnati, OH (United States)

1995-11-01

17

THE LOADS OF PAHS IN WASTEWATER AND SEWAGE SLUDGE OF MUNICIPAL TREATMENT PLANT  

Microsoft Academic Search

Sewage and sewage sludge from a municipal wastewater treatment plant were analyzed for 16 EPA-PAHs. This plant is a classic mechanical-biological treatment plant, consisting of activated sludge technology with additional chemical treatment for the removal of phosphorus compounds. The process of sewage sludge treatment is carried out in closed as well as open sludge digesters. Primary and mechanically thickened sludge

Maria Wlodarczyk-Makula

2005-01-01

18

Cultivation of aerobic granular sludge for rubber wastewater treatment.  

PubMed

Aerobic granular sludge (AGS) was successfully cultivated at 27±1 °C and pH 7.0±1 during the treatment of rubber wastewater using a sequential batch reactor system mode with complete cycle time of 3 h. Results showed aerobic granular sludge had an excellent settling ability and exhibited exceptional performance in the organics and nutrients removal from rubber wastewater. Regular, dense and fast settling granule (average diameter, 1.5 mm; settling velocity, 33 m h(-1); and sludge volume index, 22.3 mL g(-1)) were developed in a single reactor. In addition, 96.5% COD removal efficiency was observed in the system at the end of the granulation period, while its ammonia and total nitrogen removal efficiencies were up to 94.7% and 89.4%, respectively. The study demonstrated the capabilities of AGS development in a single, high and slender column type-bioreactor for the treatment of rubber wastewater. PMID:23317554

Rosman, Noor Hasyimah; Nor Anuar, Aznah; Othman, Inawati; Harun, Hasnida; Sulong Abdul Razak, Muhammad Zuhdi; Elias, Siti Hanna; Mat Hassan, Mohd Arif Hakimi; Chelliapan, Shreesivadass; Ujang, Zaini

2013-02-01

19

Impact of secondary treatment types and sludge handling processes on estrogen concentration in wastewater sludge.  

PubMed

Endocrine-disrupting compounds (EDCs), such as estrogen, are known to be present in the aquatic environment at concentrations that negatively affect fish and other wildlife. Wastewater treatment plants (WWTPs) are major contributors of EDCs into the environment. EDCs are released via effluent discharge and land application of biosolids. Estrogen removal in WWTPs has been studied in the aqueous phase; however, few researchers have determined estrogen concentration in sludge. This study focuses on estrogen concentration in wastewater sludge as a result of secondary treatment types and sludge handling processes. Grab samples were collected before and after multiple treatment steps at two WWTPs receiving wastewater from the same city. The samples were centrifuged into aqueous and solid phases and then processed using solid phase extraction. Combined natural estrogens (estrone, estradiol and estriol) were measured using an enzyme-linked immunosorbent assay (ELISA) purchased from a manufacturer. Results confirmed that activated sludge treatments demonstrate greater estrogen removal compared to trickling filters and mass concentration of estrogen was measured for the first time on trickling filter solids. Physical and mechanical sludge treatment processes, such as gravity thickeners and centrifuges, did not significantly affect estrogen removal based on mass balance calculations. Dissolved air flotation thickening demonstrated a slight decrease in estrogen concentration, while anaerobic digestion resulted in increased mass concentration of estrogen on the sludge and a high estrogen concentration in the supernatant. Although there are no state or federally mandated discharge effluent standards or sludge application standards for estrogen, implications from this study are that trickling filters would need to be exchanged for activated sludge treatment or followed by an aeration basin in order to improve estrogen removal. Also, anaerobic digestion may need to be replaced with aerobic digestion for sludge that is intended for land application. PMID:24239827

Marti, Erica J; Batista, Jacimaria R

2014-02-01

20

Development of anaerobic sludge bed (ASB) reactor technologies for domestic wastewater treatment: motives and perspectives  

Microsoft Academic Search

During the treatment of raw domestic wastewater in the upflow anaerobic sludge blanket (UASB) reactor, the suspended solids (SS) present in the wastewater tend to influence negatively the methanogenic activity and the chemical oxygen demand (COD) conversion efficiency. These problems led to the emergence of various anaerobic sludge bed systems such as the expanded granular sludge bed (EGSB), the upflow

Youssouf Kalogo; Willy Verstraete

1999-01-01

21

Anaerobic stabilisation of sludge produced during municipal wastewater treatment by electrocoagulation.  

PubMed

Anaerobic digestion of sludge from small electrocoagulation wastewater treatment plant (SEWWTP) is described. The sludge for digestion (SEWWTP sludge) was taken from pilot-scale SEWWTP with the capacity of about 200-population equivalent (25 m3 of municipal wastewater per day). Due to the technology of wastewater treatment, the characteristics of SEWWTP sludge was different from sludge produced in conventional mechanical-biological wastewater treatment plant. Therefore, experiments were focused on possibilities of anaerobic sludge digestion and determination of conditions and parameters (amount and quality of the sludge, biogas production, etc.). Average COD removal efficiency in the pilot-scale SEWWTP exceeded 80%. Organic content of excess sludge (volatile suspended solids (VSS)) was in the range of 52.1-59.2% (these values are much lower compared to VSS content in raw sludge from conventional municipal wastewater treatment plant, where VSS is about 75%). Biogas production from anaerobic digestion of SEWWTP sludge was approximately three times lower compared to standard production in conventional municipal wastewater treatment plant. Low pH (6.5-6.7), high concentration of iron (up to 1400 mg/L) and aluminium (up to 1300 mg/L) and very low (almost zero) concentration of dissolved phosphorus in sludge water were the main factors limiting the rate of anaerobic processes. Based on these results, anaerobic digestion of SEWWTP sludge was not recommended as an appropriate stabilisation method. PMID:16297548

Hutnan, M; Drtil, M; Kalina, A

2006-04-17

22

Treatment of refinery wastewaters using various modified activated sludge processes  

SciTech Connect

Biological processes for treating refinery industry wastewater for reuse were studied. A pilot-scale biological reactor was constructed to simulate the activated sludge treatment process. Actual refinery industry wastewater collected from a regional refinery and spiked with additions of selected priority organics was fed at a rate of 1.3 liters/hour into a 6-liter pilot plant having a hydraulic retention time of 4 hours. Activated sludge (AS) which was augmented by additions of powdered activated carbon (PAC) at dosages of 10, 50 and 120 mg/l was evaluated. The AS process removed 70-80% of the BOD, COD and TOC. With the addition of PAC, removal efficiencies of the indicator compounds rose to 80-95%. The sludge physical parameters and kinetic constants were determined with and without the addition of PAC to the AS. PAC additions to the AS increased the amount of biomass in the reactor. Volatile compounds (benzene, chloroform, ethylbenzene, toluene, m-xylene and o-xylene) were removed from the reactor by volatilization which occurred from air stripping. PAC alone (without AS) was primarily responsible for removing base and acid/neutral-extractable compounds (2,4-dimethylphenol, fluorene, naphthalene and pyrene).

Al-Muzaini, S.M.

1987-01-01

23

Synergistic cooperation between wastewater-born algae and activated sludge for wastewater treatment: influence of algae and sludge inoculation ratios.  

PubMed

An algal-bacterial culture, composed of wastewater-born algae and activated sludge, was cultivated to treat domestic wastewater and accumulate biomass simultaneously. The influence of algae and sludge inoculation ratios on the treatment efficiency and the settleability of the accumulated biomass were investigated. There was no significant effect of the inoculation ratios on the chemical oxygen demand removal. Comparatively, the nutrients removal and related mechanism were varied with different inoculation ratios. The highest nitrogen and phosphorus removal efficiencies were observed with 5:1 (algae/sludge) culture (91.0±7.0% and 93.5±2.5%, respectively) within 10 days, which was 5-40% higher and 2-4 days faster than those with other inoculation ratios. The biomass settleability was improved with the assistance of sludge, and the 1:5 (algae/sludge) culture showed the best settleability. Furthermore, 16S rDNA gene analysis showed that the bacterial communities were varying with different algae and sludge inoculation ratios and some specific bacteria were enriched during operation. PMID:22189078

Su, Yanyan; Mennerich, Artur; Urban, Brigitte

2012-02-01

24

COMPOSTING OF MUNICIPAL WASTEWATER SLUDGES  

EPA Science Inventory

The seminar publication provides practical information on current methods of composting municipal wastewater sludges. It is intended for government and private sector individuals involved in the planning, design, and operation of municipal sludge treatment and disposal systems. C...

25

Production of biodegradable plastics from activated sludge generated from a food processing industrial wastewater treatment plant  

Microsoft Academic Search

Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of biodegradable plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as biodegradable plastics. However, widespread applications have been limited by high production cost. In the present study,

M Suresh Kumar; S. N Mudliar; K. M. K Reddy; T Chakrabarti

2004-01-01

26

Electro-coagulation treatment of oily wastewater with sludge analysis.  

PubMed

Experiments were carried out in a batch reactor to treat the oily effluent by electro-coagulation. The influence of operating parameters such as applied current, type of electrode and electrolysis time on electro-coagulation efficiency has been critically examined. The maximum percentage removal of chemical oxygen demand (COD) was 94% under optimum experimental conditions of pH 6.7, current density 6 mA/cm², electrolysis time 40 min, and using mild steel as anode. The remaining sludge in the reactor was analyzed by energy disperse analysis of X-rays (EDAX) and scanning electron microscope (SEM) analysis. The analysis confirms that the oily pollutant was removed by electroflotation and adsorption of the oily particles of precipitate during the electro-coagulation process. Electro-coagulation can be used as an efficient treatment technique for oily wastewater. PMID:23109567

Ibrahim, Dhorgham Skban; Sakthipriya, N; Balasubramanian, N

2012-01-01

27

A strategy in wastewater treatment process for significant reduction of excess sludge production.  

PubMed

A novel wastewater treatment process (S-TE PROCESS) with significantly reduced production of excess sludge has been developed. The process consists of two different stages, one for a biological wastewater treatment and the other for a thermophilic aerobic digestion of the resulting sludge. A portion of return sludge from the wastewater treatment step is injected into a thermophilic aerobic sludge digester (TASD), in which the injected sludge is solubilized by the action of thermophilic aerobic bacteria. The solubilized sludge is returned to the aeration tank in the wastewater treatment step for its further degradation. Pilot-scale facilities of the S-TE process and the conventional activated sludge process as a control, both treating the same industrial wastewater, were comparatively operated for totally 270 days. As a result, 93% reduction in overall excess sludge production was achieved in the S-TE operation. The SS solubilization rate in TASD was stable at around 30%. Only a slight increase in the effluent SS and TOC concentrations was observed compared with those of the control facility. Otherwise the removal efficiency of TOC was approximately 95% for both plants. A full-scale plant treating domestic sewage was operated for three years, showing 75% reduction of overall excess sludge production. It was concluded that the new process was feasible. PMID:12201093

Shiota, N; Akashi, A; Hasegawa, S

2002-01-01

28

Long term in-line sludge storage in wastewater treatment plants: the potential for phosphorus release  

Microsoft Academic Search

Phosphorus removal in on-site wastewater treatment plants is normally obtained by chemical precipitation. Aluminium-based chemicals are the favoured coagulants as they are not affected by redox potential. On-site wastewater treatment package plants do not have separate sludge treatment facilities, and sludge is normally collected on an annual basis. This can potentially increase the risk of phosphorus release into the water

Erik Johannessen; Arild Schanke Eikum; Tore Krogstad

2012-01-01

29

Continuous treatment of textile wastewater by combined coagulation, electrochemical oxidation and activated sludge  

Microsoft Academic Search

Treatment of text wastewaters from a large dyeing and finishing mill by a continuous process of combined chemical coagulation, electrochemical oxidation and activated sludge treatment is investigated. The experimental results are assessed in terms of COD and color (turbidity) reductions to determine the overall treatment efficiency of the combined process. Operating variables, such as the wastewater flow rate, conductivity, pH,

Sheng H. Lin; Chi F. Peng

1996-01-01

30

LAND TREATMENT FIELD STUDIES. VOLUME 4. SECONDARY WASTEWATER TREATMENT PLANT SLUDGE FROM A SYNTHETIC MANUFACTURING PLANT  

EPA Science Inventory

This report presents the results of field measurements and observations of a land treatment site for the management of secondary wastewater treatment sludge from a synthetics manufacturing plant. The waste, composed of 8.5% solids, contained a large concentration of cellulose and...

31

A CRITICAL REVIEW OF WASTEWATER TREATMENT PLANT SLUDGE DISPOSAL BY LANDFILLING  

EPA Science Inventory

This report evaluates the landfilling of wastewater treatment plant sludge for purposes of describing current practices, determining environmental and public health impacts, describing available control technology, and evaluating management options. The potential environmental/pu...

32

American Advances in Wastewater Treatment Related to Toxics Control and to Sludge Management,  

National Technical Information Service (NTIS)

Research emphasis by the United States Environmental Protection Agency in wastewater treatment has focussed on control of toxics and sludge management. The paper describes highlights of the Environmental Protection Agency's research in these areas. The re...

D. F. Bishop J. B. Farrell K. M. Lee

1987-01-01

33

Activated Sludge with Powdered Activated Carbon Treatment of a Dyes and Pigments Processing Wastewater.  

National Technical Information Service (NTIS)

This paper discusses completed efforts in the treatment of dyes and pigments processing wastewater utilizing the activated sludge process (ASP) enhanced with powdered activated carbon (PAC). The independent variables of the study were solids retention tim...

G. M. Shaul M. W. Barnett T. W. Neiheisel K. A. Dostal

1983-01-01

34

AMERICAN ADVANCES IN WASTEWATER TREATMENT RELATED TO TOXICS CONTROL AND TO SLUDGE MANAGEMENT  

EPA Science Inventory

Research emphasis by the United States Environmental Protection Agency in wastewater treatment has focussed on control of toxics and sludge management. The paper describes highlights of the Environmental Protection Agency's research in these areas. The research on toxics control ...

35

Conversion of Municipal Wastewater Treatment Plant Residual Sludges into Earthworm Castings for Use as Topsoil.  

National Technical Information Service (NTIS)

Vermicomposting, or biodegradation of waste water sludge from the San Jose and Santa Clara Wastewater Treatment Plants in California, was accomplished by the use of earthworms of the redworm (Eisenia foetida) species. Ninety tons of earthworm manure were ...

J. E. Collier D. Livingstone

1981-01-01

36

BIOLOGICAL RISKS ASSOCIATED WITH THE COMPOSTING OF WASTEWATER TREATMENT PLANT SLUDGE  

EPA Science Inventory

Personnel employed at wastewater treatment plant sludge composting operations are exposed to a variety of viable gram-negative bacteria, and fungi as well as microbial products such as endotoxin (lipopolysaccharide (LPS)) in their work environment. This investigation was designed...

37

Reed beds: constructed wetlands for municipal wastewater treatment plant sludge dewatering  

Microsoft Academic Search

Reed beds are an alternative technology wastewater treatment system that mimic the biogeochemical processes inherent in natural wetlands. The purpose of this project was to determine the effectiveness of a reed bed sludge treatment system (RBSTS) in southern New England after a six-year period of operation by examining the concentrations of selected metals in the reed bed sludge biomass and

J. S. Begg; R. L. Lavigne; P. L. M. Veneman

38

Use of Pulverized Coal to Enhance Sludge Dewatering and Incineration at Amherst Wastewater Treatment Facility.  

National Technical Information Service (NTIS)

The addition of pulverized coal to sewage sludge prior to incineration was investigated as a cost-saving measure for the 24 mgd two-stage complete-mix 'UNOX' activated sludge wastewater treatment plant with a physical-chemical tertiary treatment system in...

L. T. Thiem R. R. Roll

1983-01-01

39

Municipal wastewater treatment by periodic biofilter without excess sludge production.  

PubMed

The paper reports the results of an investigation aimed at evaluating the performances of a periodic biofilter (SBBR) for treating municipal wastewater. The investigation was carried out at laboratory scale on real primary effluent coming from a municipal wastewater treatment plant located in Southern Italy. The SBBR was designed for carbon and nitrogen removal through one single stage. The results have shown that even at maximum organic load (i.e., 7 kg COD/m3.d), the COD in the effluent was lower than 60 mg/L. TKN removal efficiencies resulted high (i.e. 90-95%) up to an organic load of 5.7 kg COD/m3.d corresponding to a nitrogen load of 0.8 kg TKN/m3.d. NO3-N concentration in the treated effluent was lesser than 6 mg/L although in the SBBR treatment cycle no anoxic phase was scheduled. This indicated that denitrification extensively took place in the biofilter. The process was characterized by high suspended solids removal (about 90%) and by a negligible sludge production (lower than 0.01 kgVSS/kgCODremoved). In the SBBR, biomass grew as granules and was characterised by different measurements (biomass concentration, cellular protein and biomass density). Biomass density resulted very high, i.e. 200 gTSS/Lbiomass, and this permitted to achieve a biomass concentration such high as 40 gTSS/Lbed. Such biomass concentration did not cause any decrease of biomass metabolic activity as proved by its total protein content (29% of organic matter) and maximum oxygen uptake rate value (i.e. 50 mgO2/gVSS h). PMID:16136839

Di Iaconi, Claudio; Ramadori, Roberto; Lopez, Antonio; Passino, Roberto

2005-06-01

40

Optimization of diclofenac quantification from wastewater treatment plant sludge by ultrasonication assisted extraction.  

PubMed

A rapid quantification method of diclofenac from sludge samples through ultrasonication assisted extraction and solid phase extraction (SPE) was developed and used for the quantification of diclofenac concentrations in sludge samples with liquid chromatography/tandem mass spectrometry (LC-MS/MS). Although the concentration of diclofenac in sludge samples taken from different units of wastewater treatment plants in Istanbul was below the limit of quantification (LOQ; 5ng/g), an optimized method for sludge samples along with the total mass balances in a wastewater treatment plant can be used to determine the phase with which diclofenac is mostly associated. Hence, the results will provide information on fate and transport of diclofenac, as well as on the necessity of alternative removal processes. In addition, since the optimization procedure is provided in detail, it is possible for other researchers to use this procedure as a starting point for the determination of other emerging pollutants in wastewater sludge samples. PMID:24704687

Topuz, Emel; Sari, Sevgi; Ozdemir, Gamze; Aydin, Egemen; Pehlivanoglu-Mantas, Elif; Okutman Tas, Didem

2014-05-01

41

Micro-Aerobic Granulation of Digestion Sludge in an EGSB Reactor for the Treatment of Actual Coking Wastewater  

Microsoft Academic Search

.. . ) To accomplish rapidly the micro-aerobic granulation process of digestion sludge for the treatment of actual coking wastewater and meanwhile achieve high COD, phenol SCN and CN removal, the EGSB reactor was employed with two operation stages. Stage?: Granular sludge was formed from digestion sludge using brewery wastewater as substrate in the anaerobic way (meanwhile adding little granules,

Chunjuan Dong; Wenying Li

2011-01-01

42

Micro-aerobic granulation for actual coking wastewater treatment in an expanded granular sludge bed (EGSB) reactor: Intermittent oxygenation  

Microsoft Academic Search

To accomplish rapidly the micro-aerobic granulation process of digestion sludge for the treatment of actual coking wastewater and meanwhile achieve high COD, the EGSB reactor was employed with two operation stages. Stage?? : Granular sludge was formed from digestion sludge using brewery wastewater as substrate in the anaerobic way (meanwhile adding little granules, which were 1\\/7 of the total biomass).

Dong Chunjuan; Geng Zhaoyu; Li Wenying

2011-01-01

43

Critical operational parameters for zero sludge production in biological wastewater treatment processes combined with sludge disintegration.  

PubMed

Mathematical models were developed to elucidate the relationships among process control parameters and the effect of these parameters on the performance of anoxic/oxic biological wastewater processes combined with sludge disintegrators (A/O-SD). The model equations were also applied for analyses of activated sludge processes hybrid with sludge disintegrators (AS-SD). Solubilization ratio of sludge in the sludge disintegrator, alpha, hardly affected sludge reduction efficiencies if the biomass was completely destructed to smaller particulates. On the other hand, conversion efficiency of non-biodegradable particulates to biodegradable particulates, beta, significantly affected sludge reduction efficiencies because beta was directly related to the accumulation of non-biodegradable particulates in bioreactors. When 30% of sludge in the oxic tank was disintegrated everyday and beta was 0.5, sludge reduction was expected to be 78% and 69% for the A/O-SD and AS-SD processes, respectively. Under this condition, the sludge disintegration number (SDN), which is the amount of sludge disintegrated divided by the reduced sludge, was calculated to be around 4. Due to the sludge disintegration, live biomass concentration decreased while other non-biodegradable particulates concentration increased. As a consequence, the real F/M ratio was expected to be much higher than the apparent F/M. The effluent COD was maintained almost constant for the range of sludge disintegration rate considered in this study. Nitrogen removal efficiencies of the A/O-SD process was hardly affected by the sludge disintegration until daily sludge disintegration reaches 40% of sludge in the oxic tank. Above this level of sludge disintegration, autotrophic biomass concentration decreases overly and TKN in the effluent increases abruptly in both the A/O-SD and AS-SD processes. Overall, the trends of sludge reduction and effluent quality according to operation parameters matched well with experimental results found in literatures. PMID:16061269

Yoon, Seong-Hoon; Lee, Sangho

2005-09-01

44

40 CFR 721.10636 - Slimes and sludges, automotive coating, wastewater treatment, solid waste.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Slimes and sludges, automotive coating, wastewater...Chemical Substances § 721.10636 Slimes and sludges, automotive coating, wastewater...The chemical substance identified as slimes and sludges, automotive...

2013-07-01

45

Aluminium Salts Hydrolysis Products from Industrial Anodising Sludges in Wastewater Treatment  

NASA Astrophysics Data System (ADS)

The wastewaters resulting from industrial aluminium anodising processes must be treated in a wastewater treatment plant usually involving the main operations of neutralisation, flocculation, settling and filtration with a press-filter. In Portugal the annual quantity of sludges, resulting from these wastewaters treatment, is estimated in 15 000 t/year (2002) and in the EU a large quantity is also involved. No use has been found for these sludges and they are sent to landfills or disposed of in uncontrolled places. Recycling is an economical and environmentally friendly way to handle hazardous wastes, reducing the amounts disposed in landfills. So the effect of the anodising sludge as flocculant of municipal wastewaters instead of inorganic salts commonly used was studied.

Chambino, Teresa; Correia, Anabela; Barany, Sandor

46

Operating aerobic wastewater treatment at very short sludge ages enables treatment and energy recovery through anaerobic sludge digestion.  

PubMed

Conventional abattoir wastewater treatment processes for carbon and nutrient removal are typically designed and operated with a long sludge retention time (SRT) of 10-20 days, with a relatively high energy demand and physical footprint. The process also generates a considerable amount of waste activated sludge that is not easily degradable due to the long SRT. In this study, an innovative high-rate sequencing batch reactor (SBR) based wastewater treatment process with short SRT and hydraulic retention time (HRT) is developed and characterised. The high-rate SBR process was shown to be most effective with SRT of 2-3 days and HRT of 0.5-1 day, achieving >80% reduction in chemical oxygen demand (COD) and phosphorus and approximately 55% nitrogen removal. A majority of carbon removal (70-80%) was achieved by biomass assimilation and/or accumulation, rather than oxidation. Anaerobic degradability of the sludge generated in the high-rate SBR process was strongly linked to SRT, with measured degradability extent being 85% (2 days SRT), 73% (3 days), and 63% (4 days), but it was not influenced by digestion temperature. However, the rate of degradation for 3 and 4 days SRT sludge was increased by 45% at thermophilic conditions compared to mesophilic conditions. Overall, the treatment process provides a very compact and energy efficient treatment option for highly degradable wastewaters such as meat and food processing, with a substantial space reduction by using smaller reactors and a considerable net energy output through the reduced aerobic oxidation and concurrent increased methane production potential through the efficient sludge digestion. PMID:24045213

Ge, Huoqing; Batstone, Damien J; Keller, Jurg

2013-11-01

47

A Guide for Developing Standard Operating Job Procedures for the Sludge Conditioning & Dewatering Process Wastewater Treatment Facility. SOJP No. 11.  

ERIC Educational Resources Information Center

This guide describes standard operating job procedures for the sludge conditioning and dewatering process of wastewater treatment facilities. In this process, sludge is treated with chemicals to make the sludge coagulate and give up its water more easily. The treated sludge is then dewatered using a vacuum filter. The guide gives step-by-step…

Schwing, Carl M.

48

Physicochemical and thermal characteristics of the sludge produced after thermochemical treatment of petrochemical wastewater.  

PubMed

The present work describes the physicochemical and thermal characteristics of the sludge generated after thermochemical treatment of wastewater from a petrochemical plant manufacturing purified terephthalic acid (PTA). Although FeCl3 was found to be more effective than CuSO4 in removing COD from wastewater, the settling and filtration characteristics of FeCl3 sludge were poorer. Addition of cationic polyacrylamide (CPAA; 0.050kg/m3) to the FeCl3 wastewater system greatly improved the values of the filter characteristics of specific cake resistance (1.2 x 10(8) m/kg) and resistance of filter medium (9.9 x 10(8) m(-1)) from the earlier values of 1.9 x 10(9) m/kg and 1.7 x 10(8) m(-1), respectively. SEM-EDAX and FTIR studies were undertaken, to understand the sludge structure and composition, respectively. The moisture distribution in the CuSO4 sludge, FeCl3 sludge and FeCl3 + CPAA sludge showed that the amount of bound water content in the CuSO4 and FeCl3 + CPAA sludges is less than that of the FeCl3 sludge and there was a significant reduction in the solid-water bond strength of FeCl3 + CPAA sludge, which was responsible for better settling and filtration characteristics. Due to the hazardous nature of the sludge, land application is not a possible route of disposal. The thermal degradation behaviour of the sludge was studied for its possible use as a co-fuel. The studies showed that degradation behaviour of the sludge was exothermic in nature. Because of the exothermic nature of the sludge, it can be used in making fuel briquettes or it can be disposed of via wet air oxidation. PMID:22988641

Verma, Shilpi; Prasad, Basheshwar; Mishra, I M

2012-01-01

49

Application of ozonation to reduce biological sludge production in an industrial wastewater treatment plant.  

PubMed

Biosolids production in the activated sludge process generates an additional cost to wastewater treatment plants due to the growing requirements for sludge treatment and disposal. This work focuses on the application of ozonation to reduce sludge production in an industrial wastewater treatment plant. The results show that ozonation was able to promote cell wall rupture, releasing intracellular matter into the liquid medium. This effect was observed by the increase in concentrations of DNA (1.14 to 7.83 mg/L) and proteins (0.5 to 45.602 mg/L) in the liquid phase, when ozonation was applied during 10 min, using 30 mg/L of ozone. Reduction of sludge production was assessed by calculating the observed sludge yield coefficient (Y) in bench-scale continuous experiments conducted with varying proportions of ozonated sludge in the recycle stream and recycle ratios. Reduction of sludge production ranged from 14 to 39%, depending on the experimental conditions. The best result in terms of sludge excess reduction was achieved when 20% of the recycle sludge was ozonated and the recycle ratio was 0.67. PMID:19039177

Albuquerque, J S; Domingos, J C; Sant'Anna, G L; Dezotti, M

2008-01-01

50

Use of dewatered alum sludge as a substrate in reed bed treatment systems for wastewater treatment.  

PubMed

In this paper, two laboratory-scale simulated reed beds were investigated for the purpose of assessing the feasibility and effectiveness of using dewatered alum sludge as a possible substrate for wastewater treatment reed bed systems. One horizontal subsurface flow setup and one vertical flow setup were used. The horizontal flow system was planted with Phragmites australis while the vertical flow system was left unplanted. Thus, the latter was more akin to a sand filter system, but was examined with the potential use as a planted vertical reed bed system. The influent source used was farmyard wastewater. It is expected that the present study will provide the basis for long-term and large-scale trials in realizing the concept of integrating "waste" into treatment processes. Results obtained so far have shown that the dewatered alum sludge holds great promise as a low-cost resource media for use in reed bed treatment systems. Appreciable and stable performance was obtained during the continuous operation at high hydraulic, organic and phosphorus loadings. In particular, both wetlands achieved over 90% phosphorus removal, reflecting the significant advantage of this novel approach over conventional reed bed treatment systems. However, extensive research into possible surface clogging and possible release of some substances from the sludge to the treated effluent is necessary to ensure reliability of the system. This will help to make the alum sludge-based reed bed environmentally and economically justifiable. PMID:18161564

Zhao, Y Q; Babatunde, A O; Razali, M; Harty, F

2008-01-01

51

Characterization, Modeling and Application of Aerobic Granular Sludge for Wastewater Treatment  

NASA Astrophysics Data System (ADS)

Recently extensive studies have been carried out to cultivate aerobic granular sludge worldwide, including in China. Aerobic granules, compared with conventional activated sludge flocs, are well known for their regular, dense, and strong microbial structure, good settling ability, high biomass retention, and great ability to withstand shock loadings. Studies have shown that the aerobic granules could be applied for the treatment of low- or high-strength wastewaters, simultaneous removal of organic carbon, nitrogen and phosphorus, and decomposition of toxic wastewaters. Thus, this new form of activate sludge, like anaerobic granular sludge, could be employed for the treatment of municipal and industrial wastewaters in near future. This chapter attempts to provide an up-to-date review on the definition, cultivation, characterization, modeling and application of aerobic granular sludge for biological wastewater treatment. This review outlines some important discoveries with regard to the factors affecting the formation of aerobic granular sludge, their physicochemical characteristics, as well as their microbial structure and diversity. It also summarizes the modeling of aerobic granule formation. Finally, this chapter highlights the applications of aerobic granulation technology in the biological wastewater treatment. It is concluded that the knowledge regarding aerobic granular sludge is far from complete. Although previous studies in this field have undoubtedly improved our understanding on aerobic granular sludge, it is clear that much remains to be learned about the process and that many unanswered questions still remain. One of the challenges appears to be the integration of the existing and growing scientific knowledge base with the observations and applications in practice, which this paper hopes to partially achieve.

Liu, Xian-Wei; Yu, Han-Qing; Ni, Bing-Jie; Sheng, Guo-Ping

52

Examination of the operator and compensator tank role in urban wastewater treatment using activated sludge method.  

PubMed

No doubt, operator is one of the main fundaments in wastewater treatment plants. By identifying the inadequacies, the operator could be considered as an important key in treatment plant. Several methods are used for wastewater treatment that requires spending a lot of cost. However, all investments of treatment facilities are usable when the expected efficiency of the treatment plant was obtained. Using experienced operator, this goal is more easily accessible. In this research, the wastewater of an urban community contaminated with moderated, diluted and highly concentrated pollution has been treated using surface and deep aeration treatment method. Sampling of these pilots was performed during winter 2008 to summer 2009. The results indicate that all analyzed parameters were eliminated using activated sludge and surface aeration methods. However, in activated sludge and deep aeration methods in combination with suitable function of operator, more pollutants could be eliminated. Hence, existence of operator in wastewater treatment plants is the basic principle to achieve considered efficiency. Wastewater treatment system is not intelligent itself and that is the operator who can organize even an inefficient system by its continuous presence. The converse of this fact is also real. Despite the various units and appropriate design of wastewater treatment plant, without an operator, the studied process cannot be expected highly efficient. In places frequently affected by the shock of organic and hydraulic loads, the compensator tank is important to offset the wastewater treatment process. Finally, in regard to microbial parameters, existence of disinfection unit is very useful. PMID:20571882

Mokhtari Azar, Akbar; Ghadirpour Jelogir, Ali; Nabi Bidhendi, Gholam Reza; Zaredar, Narges

2011-04-01

53

Diversity and dynamics of Archaea in an activated sludge wastewater treatment plant  

PubMed Central

Background The activated sludge process is one of the most widely used methods for treatment of wastewater and the microbial community composition in the sludge is important for the process operation. While the bacterial communities have been characterized in various activated sludge systems little is known about archaeal communities in activated sludge. The diversity and dynamics of the Archaea community in a full-scale activated sludge wastewater treatment plant were investigated by fluorescence in situ hybridization, terminal restriction fragment length polymorphism analysis and cloning and sequencing of 16S rRNA genes. Results The Archaea community was dominated by Methanosaeta-like species. During a 15?month period major changes in the community composition were only observed twice despite seasonal variations in environmental and operating conditions. Water temperature appeared to be the process parameter that affected the community composition the most. Several terminal restriction fragments also showed strong correlations with sludge properties and effluent water properties. The Archaea were estimated to make up 1.6% of total cell numbers in the activated sludge and were present both as single cells and colonies of varying sizes. Conclusions The results presented here show that Archaea can constitute a constant and integral part of the activated sludge and that it can therefore be useful to include Archaea in future studies of microbial communities in activated sludge.

2012-01-01

54

Production of biodegradable plastics from activated sludge generated from a food processing industrial wastewater treatment plant.  

PubMed

Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of biodegradable plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as biodegradable plastics. However, widespread applications have been limited by high production cost. In the present study, activated sludge bacteria in a conventional wastewater treatment system were induced, by controlling the carbon: nitrogen ratio to accumulate storage polymers. Polymer yield increased to a maximum 33% of biomass (w/w) when the C/N ratio was increased from 24 to 144, where as specific growth yield decreased with increasing C/N ratio. The conditions which are required for the maximum polymer accumulation were optimized and are discussed. PMID:15288276

Suresh Kumar, M; Mudliar, S N; Reddy, K M K; Chakrabarti, T

2004-12-01

55

Rheology Measurements for Online Monitoring of Solids in Activated Sludge Reactors of Municipal Wastewater Treatment Plant  

PubMed Central

Rheological behaviour of recycled sludge from a secondary clarifier of a municipal wastewater treatment plant was studied by using the rate controlled coaxial cylinder viscometer Rotovisko-Haake 20, system M5-osc., measuring device NV. The tests (hysteresis cycles) were performed under continuous flow conditions and following an ad hoc measurement protocol. Sludge shear stress versus shear rate curves were fitted very satisfactorily by rheological models. An experimental equation correlating the solid concentration of sludge to relative viscosity and fitting satisfactorily flow curves at different Total Suspended Solids (TTS%) was obtained. Application of the empirical correlation should allow the monitoring of the proper functioning of a wastewater treatment plant measuring viscosity of sludge.

Papo, Adriano; Goi, Daniele

2014-01-01

56

Wastewater treatment and poly-?-hydroxybutyrate production using lighted upflow anaerobic sludge blanket method  

Microsoft Academic Search

We investigated the performance of a lighted upflow anaerobic sludge blanket (LUASB) reactor for wastewater treatment and poly-?-hydroxybutyrate (PHB) production. Phototrophic bacteria were induced from UASB (upflow anaerobic sludge blanket) granules under light conditions (100 ?E•m?2•s?1). The ammonium and phosphate ion removal efficiencies of the LUASB reactor were higher than those of the UASB reactor. The difference in the results

Shigeki Sawayama; Kenichiro Tsukahara; Tatsuo Yagishita

1999-01-01

57

IASON – Intelligent Activated Sludge Operated by Nanotechnology – Hydrogel Microcarriers in Wastewater Treatment  

Microsoft Academic Search

Performance of biological wastewater treatment depends to a large extent on mechanical strength,\\u000a size distribution, permeability and other textural properties of the activated sludge flocs. A novel\\u000a approach was developed in applying synthetic polymer materials to organize floc architecture instead of\\u000a spontaneously formed activated sludge floc. Developed microcarrier polymer materials were used in our experiments\\u000a to mitigate technological goals. Preliminary results suggest

E. Fleit; Z. Melicz; D. Sándor; M. Zrínyi; G. Filipcsei; K. László; I. Dékány; Z. Király

58

Psychoactive pharmaceuticals in sludge and their emission from wastewater treatment facilities in Korea.  

PubMed

Concern over the occurrence of pharmaceuticals and their metabolites in the environment is mounting due to the potential adverse effects on nontarget organisms. This study draws upon a nationwide survey of psychoactive pharmaceuticals (i.e., antischizophrenics, anxiolytics, and antidepressants) in sludge from 40 representative wastewater treatment plants (WWTPs) that receive domestic, industrial, or mixed (domestic plus industrial) wastewaters in Korea. A total of 16 psychoactive pharmaceuticals (0.12-460 ng/g dry weight) and nine of their metabolites (0.97-276 ng/g dry weight) were determined in sludge. The median concentrations of psychoactive drugs in sludge from domestic WWTPs were 1.2-3.2 times higher than the concentrations found in WWTPs that receive combined domestic and industrial wastewaters. Among the psychoactive drugs analyzed, the median environmental emission rates of alprazolam (APZ) and carbamazepine (CBZ) through domestic WWTPs (both sludge and effluent discharges combined) were calculated to be ? 15.5 ?g/capita/day, followed by quetiapine (QTP; 8.51 ?g/capita/day), citalopram (CLP; 5.45 ?g/capita/day), and venlafaxine (VLF; 3.59 ?g/capita/day). The per-capita emission rates of some of the metabolites of psychoactive drugs through WWTP discharges were higher than those calculated for parent compounds. Significant correlations (? = 0.432-0.780, p < 0.05) were found between the concentrations of typically coprescribed antischizophrenics and antidepressants in sludge. Multiple linear regression analysis of measured concentrations of drugs in sludge revealed that several WWTP parameters such as treatment capacity, population-served, sludge production rate, composition of wastewater (domestic versus industrial), and hydraulic retention time can affect the concentrations of psychoactive drugs in sludge. PMID:24164172

Subedi, Bikram; Lee, Sunggyu; Moon, Hyo-Bang; Kannan, Kurunthachalam

2013-12-01

59

A full scale worm reactor for efficient sludge reduction by predation in a wastewater treatment plant.  

PubMed

Sludge predation can be an effective solution to reduce sludge production at a wastewater treatment plant. Oligochaete worms are the natural consumers of biomass in benthic layers in ecosystems. In this study the results of secondary sludge degradation by the aquatic Oligochaete worm Aulophorus furcatus in a 125 m(3) reactor and further sludge conversion in an anaerobic tank are presented. The system was operated over a period of 4 years at WWTP Wolvega, the Netherlands and was fed with secondary sludge from a low loaded activated sludge process. It was possible to maintain a stable and active population of the aquatic worm species A. furcatus during the full period. Under optimal conditions a sludge conversion of 150-200 kg TSS/d or 1.2-1.6 kg TSS/m(3)/d was established in the worm reactor. The worms grew as a biofilm on carrier material in the reactor. The surface specific conversion rate reached 140-180 g TSS/m(2)d and the worm biomass specific conversion rate was 0.5-1 g TSS sludge/g dry weight worms per day. The sludge reduction under optimal conditions in the worm reactor was 30-40%. The degradation by worms was an order of magnitude larger than the endogenous conversion rate of the secondary sludge. Effluent sludge from the worm reactor was stored in an anaerobic tank where methanogenic processes became apparent. It appeared that besides reducing the sludge amount, the worms' activity increased anaerobic digestibility, allowing for future optimisation of the total system by maximising sludge reduction and methane formation. In the whole system it was possible to reduce the amount of sludge by at least 65% on TSS basis. This is a much better total conversion than reported for anaerobic biodegradability of secondary sludge of 20-30% efficiency in terms of TSS reduction. PMID:21943885

Tamis, J; van Schouwenburg, G; Kleerebezem, R; van Loosdrecht, M C M

2011-11-15

60

Activated sludge monitoring of a wastewater treatment plant using image analysis and partial least squares regression  

Microsoft Academic Search

The biomass present in a wastewater treatment plant was surveyed and their morphological properties related with operating parameters such as the total suspended solids (TSS) and sludge volume index (SVI). For that purpose image analysis was used to provide the morphological data subsequently treated by partial least squares regression (PLS) multivariable statistical technique. The results denoted the existence of a

A. L. Amaral; E. C. Ferreira

2005-01-01

61

ACTIVATED SLUDGE WITH POWDERED ACTIVATED CARBON TREATMENT OF A DYES AND PIGMENTS PROCESSING WASTEWATER  

EPA Science Inventory

This paper discusses completed efforts in the treatment of dyes and pigments processing wastewater utilizing the activated sludge process (ASP) enhanced with powdered activated carbon (PAC). The independent variables of the study were solids retention time (SRT) and PAC dosage. T...

62

An Assessment of the Power Generated With Plasma Processing of Sludge From Wastewater Treatment Plants  

Microsoft Academic Search

This paper is an assessment of a power that is generated with plasma processing of sludge from wastewater treatment plants. Besides fusion, the generation of electrical power is one of the novel and more relevant applications of plasma. The magmavication or vitrification, the gasification or synthesis gas production, and the generation of electrical power are briefly reviewed. The environmental advantage

Edbertho Leal-Quiros; C. R. Villafafie

2007-01-01

63

EVALUATION OF THE HEALTH RISKS ASSOCIATED WITH THE TREATMENT AND DISPOSAL OF MUNICIPAL WASTEWATER AND SLUDGE  

EPA Science Inventory

In this study, started in 1977, clinical and serologic evaluations of workers involved in composting of wastewater treatment plant sludge by the aerated pile method was initiated to evaluate the potential health effects of exposure to Aspergillus fumigatus and other viable and no...

64

Thermal Sludge Dryer Demonstration: Bird Island Wastewater Treatment Plant, Buffalo, New York.  

National Technical Information Service (NTIS)

The report describes the results of installing and testing an indirect sludge dryer, combustion testing work and analysis of heat recovery and use at the Bird Island wastewater treatment plant (WWTP). Two multiple hearth furnaces at the plant process an a...

K. M. O Beirne

1995-01-01

65

Determination of petroleum hydrocarbons and polycyclic aromatic hydrocarbons in sludge from wastewater treatment basins.  

PubMed

Screening by gas chromatography with flame ionization detection and gas chromatography-mass spectrometry has been carried out on sludge extracts of wastewater treatment basins. Soxhlet extraction with trichlorotrifluoroethane was applied. The yields for petroleum hydrocarbons and PAH recovery were high, usually in excess of 90%. The proposed investigations permit a quick assessment of petroleum pollutants in the environment. PMID:12729275

Pavlova, A; Ivanova, R

2003-04-01

66

[Research on the treatment of wastewater containing PVA by ozonation-activated sludge process].  

PubMed

The wastewater containing polyvinyl alcohol (PVA) was characterized with poor biodegradability, and was difficult to remove. In order to find an economically reasonable and practical technology, the research on the removal efficiency of different concentration wastewater containing PVA by ozonation-activated sludge process was studied, and the result was compared with the traditional activated sludge process. The results showed that the ozonation-activated sludge process was not suitable for treating influent with COD below 500 mg x L(-1) and the wastewater PVA concentration was 10-30 mg x L(-1). When the influent COD was between 500-800 mg x L(-1) and the PVA concentration was 15-60 mg x L(-1), the system had advantages on dealing with this kind of wastewater, and the average removal efficiency of COD and PVA were 92.8% and 57.4%, which were better than the traditional activated sludge process 4.1% and 15.2% respectively. In addition, the effluent concentrations of COD could keep between 30-60 mg x L(-1). When the influent COD was 1 000-1 200 mg x L(-1) and the PVA concentration was 20-70 mg x L(-1), the average removal efficiencies of COD and PVA were 90.9% and 45.3%, which were better than the traditional activated sludge process 12.8% and 12.1% respectively, but the effluent should to be further treated. Compared with the traditional activated sludge process, ozonation-activated sludge process had high treatment efficiency, stable running effect, and effectively in dealing with industrial wastewater containing PVA. PMID:23323416

Xing, Xiao-Qiong; Huang, Cheng-Lan; Liu, Min; Chen, Ying

2012-11-01

67

Ubiquity of activated sludge ferricyanide-mediated BOD methods: A comparison of sludge seeds across wastewater treatment plants.  

PubMed

Many studies have described alternatives to the BOD5 standard method, with substantial decreases in incubation time observed. However, most of these have not maintained the features that make the BOD5 assay so relevant - a high level of substrate bio-oxidation and use of wastewater treatment plant (WWTP) sludge as the biocatalyst. Two recently described ferricyanide-mediated (FM)-BOD assays, one for trade wastes and one for WWTP influents and treated effluents, satisfy these criteria and were investigated further here for their suitability for use with diverse biocatalysts. Both FM-BOD assays responded proportionately to increasing substrate concentration with sludges from 11 different WWTPs and temporally (months to years) using sludges from a single WWTP, confirming the broad applicability of both assays. Sludges from four WWTPs were selected as biocatalysts for each FM-BOD assay to compare FM-BOD equivalent values with BOD5 (three different sludge seeds) measurements for 12 real wastewater samples (six per assay). Strong and significant relationships were established for both FM-BOD assays. This study has demonstrated that sludge sourced from many WWTPs may be used as the biocatalyst in either FM-BOD assay, as it is in the BOD5 assay. The industry potential of these findings is substantial given the widespread use of the BOD5 assay, the dramatically decreased incubation period (3-6h) and the superior analytical range of both assays compared to the standard BOD5 assay. PMID:24840446

Jordan, Mark A; Welsh, David T; Teasdale, Peter R

2014-07-01

68

Relationship between pollutant content and ecotoxicity of sewage sludges from Spanish wastewater treatment plants.  

PubMed

Chemical and ecotoxicological properties of 28 sewage sludge samples from Spanish wastewater treatment plants were studied in order to assess their suitability for agricultural purposes. Sludge samples were classified into five categories according to specific treatment processes in terms of digestion (aerobic/anaerobic) and drying (mechanical/thermal). Composted samples, as indicative of the most refined process, were also considered. Sludges were subjected to physical-chemical characterization, being the sludge stabilization degree respirometrically assessed. The concentrations of seven metals (Cd, Cr, Cu, Pb, Zn, Ni, Hg) and organic substances (phenolic compounds, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated naphthalenes, polybrominated diphenyl ethers, and perfluorinated compounds) were determined. Finally, two ecotoxicological tests were performed: i) Microtox® toxicity test with Vibrio fischeri, and ii) root elongation test with Allium cepa, Lolium perenne and Raphanus sativus seeds. Significant differences were found in the following parameters: dry matter, electrical conductivity, nitrogen, organic matter and its stability, phytotoxicity and ecotoxicity, depending on the sludge treatment. In turn, no significant differences were found between categories in the concentrations of most metals and organic pollutants, with the exception of free phenolic compounds. Furthermore, no correlation between total heavy metal burden and ecotoxicity was observed. However, a good correlation was found between phenolic compounds and most ecotoxicological tests. These results suggest that sludge stability (conditioned by sludge treatment) might have a greater influence on sludge ecotoxicity than the pollutant load. Composting was identified as the treatment resulting in the lowest toxicity. PMID:22483948

Roig, Neus; Sierra, Jordi; Nadal, Martí; Martí, Esther; Navalón-Madrigal, Pedro; Schuhmacher, Marta; Domingo, José L

2012-05-15

69

Biodegradation of 14C-dicofol in wastewater aerobic treatment and sludge anaerobic biodigestion.  

PubMed

Organic micropollutants are often found in domestic and industrial effluents. Thus, it is important to learn their fate, the metabolites generated and their sorption during biological treatment processes. This work investigated the biodegradation of 14C-dicofol organochloride during wastewater aerobic treatment and sludge anaerobic biodigestion. The performance of these processes was evaluated by physical-chemical parameters. Radioactivity levels were monitored in both treatments, and residues of dicofol (DCF) and dichlorobenzophenone (DBP) were quantified by HPLC/UV. The efficiency of the aerobic and anaerobic processes was slightly reduced in the presence of DCF and DBP. After aerobic treatment, only 0.1% of DCF was mineralized, and 57% of radioactivity remained sorbed on biological sludge as DBP. After 18 days of anaerobiosis, only 3% of DCF and 5% of DBP were detected in the sludge. However, 70% of radioactivity remained in the sludge, probably as other metabolites. Dicofol was biodegraded in the investigated process, but not mineralized. PMID:22629645

Oliveira, Jaime L da M; Silva, Denise P; Martins, Edir M; Langenbach, Tomaz; Dezotti, Marcia

2012-01-01

70

Physico-chemical treatment of marble processing wastewater and the recycling of its sludge.  

PubMed

In the first part of this study, the treatability of marble processing wastewater by the coagulation-flocculation process was investigated. Optimum coagulant-flocculant doses for turbidity removal in wastewater from the cutting, faience and equalization processes were determined as 500, 200 and 500 ppm of Al2(SO4)3; 300, 500 and 300 ppm of FeCl3 and 600, 400 and 200 ppm of Agrofloc 100 (AGRON Water Treatment Technologies and Chemical Marketing Industry and Trade Limited Company, Izmir, Turkey), respectively. It was found that the removal of total solids from cutting and equalization process wastewaters was highest for the 100 ppm dosage of all chemicals used. The amount of total solids removed from faience process wastewater by Agrofloc 100 was higher than that removed by the other chemicals used. The removals of suspended solids from cutting, faience and equalization process wastewaters were similar to each other for each of the chemicals. The pH values after treatment by Agrofloc 100 were higher than the values determined after treatment by other chemicals for all process wastewater. Electrical conductivity values, however, were lower for Agrofloc 100 than for the others. Settled sludge volume experiments showed that settled sludge volumes decreased with time. The results of the quiescent settling experiment showed that the settling type could be termed flocculent settling. In the second part of the study, the usage of waste sludge from marble processing as an additive material in cement was investigated. The waste sludge originated from the wastewaters of different steps of the marble processing plant. Waste sludge was replaced with cement at various percentages by weight to prepare the mixtures of mortar. The specimens poured into the moulds were held for 24 h, removed from the moulds and held again for 28 days in lime-saturated water at 23 degrees C. Compressive and flexural strengths were evaluated with respect to percentages of waste sludge replaced with cement. The maximum compressive and flexural strengths were observed for specimens containing a 6% waste sludge when compared with control and it was also found that waste sludge up to 9% could effectively be used as an additive material in cement. PMID:16379124

Arslan, E I?il; Aslan, Sibel; Ipek, Ubeyde; Altun, Samet; Yazicio?lu, Salih

2005-12-01

71

Influence of ultrasonication and Fenton oxidation pre-treatment on rheological characteristics of wastewater sludge.  

PubMed

The effect of ultrasonication and Fenton oxidation as physico-chemical pre-treatment processes on the change of rheology of wastewater sludge was investigated in this study. Pre-treated and raw sludges displayed non-Newtonian rheological behaviour with shear thinning as well as thixotropic properties for total solids ranging from 10 g/L to 40 g/L. The rheological models, namely, Bingham plastic, Casson law, NCA/CMA Casson, IPC Paste, and power law were also studied to characterize flow of raw and pre-treated sludges. Among all rheological models, the power law was more prominent in describing the rheology of the sludges. Pre-treatment processes resulted in a decrease in pseudoplasticity of sludge due to the decrease in consistency index K varying from 42.4 to 1188, 25.6 to 620.4 and 52.5 to 317.9; and increase in flow behaviour index n changing from 0.5 to 0.35, 0.62 to 0.55 and 0.63 to 0.58, for RS, UlS and FS, respectively at solids concentration 10-40 g/L. The correlation between improvement of biodegradability and dewaterability, decrease in viscosity, and change in particle size as a function of sludge pre-treatment process was also investigated. Fenton oxidation facilitated sludge filterability resulting in capillary suction time values which were approximately 50% of the raw sludges, whereas ultrasonication with high input energy deteriorated the filterability. Biodegradability was also enhanced by the pre-treatment processes and the maximum value was obtained (64%, 77% and 73% for raw, ultrasonicated and Fenton oxidized sludges, respectively) at total solids concentration of 25 g/L. Hence, pre-treatment of wastewater sludge modified the rheological properties so that: (1) the flowability of sludge was improved for transport through the treatment train (via pipes and pumps); (2) the dewaterability of wastewater sludge was enhanced for eventual disposal and; (3) the assimilation of nutrients by microorganisms for further value-addition was increased. PMID:19574083

Pham, T T H; Brar, S K; Tyagi, R D; Surampalli, R Y

2010-01-01

72

Formation of abiological granular sludge - A facile and bioinspired proposal for improving sludge settling performance during heavy metal wastewater treatment.  

PubMed

Heavy metal contamination in wastewater poses a severe threat to the environment and public health. Chemical precipitation is the most conventional process for heavy metal wastewater treatment. However, the flocculent structure of chemical precipitation sludge raises the problem of poor sludge settling performance that is difficult to overcome. Inspired by the biological granular sludge (BGS) formation process, we report here a facile and effective strategy to produce abiological granular sludge (ABGS) to solve this problem. In this procedure, controlled double-jet precipitation was performed to simulate the cell multiplication process in BGS formation by controlling the solution supersaturation. Meanwhile, ZnO seeds and flocculant polyacrylamide were added to simulate the role of nuclei growth and extracellular polymeric substances in BGS formation process, respectively. This procedure generates ABGS with a dense structure, large size and regular spherical morphology. The settling velocity of ABGS can reach up to 3.0cms(-1), significantly higher than that of flocculent sludge (<1cms(-1)). PMID:25065787

Yan, Xu; Li, Qingzhu; Chai, Liyuan; Yang, Bentao; Wang, Qingwei

2014-10-01

73

Sludge reduction by predatory activity of aquatic oligochaetes in wastewater treatment plants: science or fiction? A review  

Microsoft Academic Search

Biological aerobic wastewater treatment plants (WWTPs) produce a lot of excess sludge. The costs for handling this residual\\u000a product are increasing, so the search for alternative techniques to reduce the amount of sludge has to be continued. Activated\\u000a sludge consists of inorganic and organic substances, bacteria, protozoa and metazoa. Due to incomplete biomass conversion,\\u000a sludge consumption yields less oligochaete biomass.

Christa H. Ratsak; Jaap Verkuijlen

74

Co-conditioning of the anaerobic digested sludge of a municipal wastewater treatment plant with alum sludge: benefit of phosphorus reduction in reject water.  

PubMed

In this study, alum sludge was introduced to co-conditioning and dewatering with an anaerobic digested sludge from a municipal wastewater treatment plant, to examine the role of the alum sludge in improving the dewaterbility of the mixed sludge and also in immobilizing phosphorus in the reject water. Experiments have demonstrated that the optimal mix ratio for the two sludges is 2:1 (anaerobic digested sludge:alum sludge: volume basis), and this can bring approximately 99% phosphorus reduction in the reject water through the adsorption of phosphorus by alum in the sludge. The phosphorus loading in wastewater treatment plants is itself derived from the recycling of reject water during the wastewater treatment process. Consequently, this co-conditioning and dewatering strategy can achieve a significant reduction in phosphorus loading in wastewater treatment plants. In addition, the use of the alum sludge has been shown to beneficially enhance the dewaterability of the resultant mixed sludge, by decreasing both the specific resistance to filtration and the capillary suction time. This is attributed to the alum sludge acting in charge neutralization and/or as adsorbent for phosphate in the aqueous phase of the sludge. Experiments have also demonstrated that the optimal polymer (Superfloc C2260, Cytec, Botlek, Netherlands) dose for the anaerobic digested sludge was 120 mg/L, while the optimal dose for the mixed sludge (mix ratio 2:1) was 15 mg/L, highlighting a huge savings in polymer addition. Therefore, from the technical perspective, the co-conditioning and dewatering strategy can be viewed as a "win-win" situation. However, for its full-scale application, integrated cost-effective analysis of process capabilities, sludge transport, increased cake disposal, additional administration, polymer saving, and so on, should be factored in. PMID:18198692

Yang, Y; Zhao, Y Q; Babatunde, A O; Kearney, P

2007-12-01

75

Disinfection of sludge using lime stabilisation and pasteurisation in a small wastewater treatment plant.  

PubMed

Removal efficiency of faecal coliforms and helminth eggs was evaluated in a small wastewater treatment plant (WWTP) serving a population of 1,000. This system was formed by the association in series of a UASB reactor and four submerged aerated biofilters. The density of faecal coliforms and the count of helminth eggs were estimated in the liquid and solid phases of the system. Two different methods of disinfecting sludge were investigated: (a) chemical treatment with lime and (b) a physical treatment by pasteurisation. As expected, the association UASB + BF was very efficient at removal of helminth eggs from the final tertiary effluent, but coliforms were still present at high densities. Lime treatment and pasteurisation of sludge were very effective methods of disinfection and produced a sludge safe for final disposal. PMID:15318480

Keller, R; Passamani-Franca, R F; Cassini, S T; Gonçalves, F R

2004-01-01

76

Preparation of ZnO nanowire using sludge from wastewater treatment.  

PubMed

In this study, we present the synthesis of ZnO nanowire by hydrothermal process through reutilization of sludge from soy sauce wastewater electrochemical treatment. The influences of floc content and caramel pigment concentration on the morphologies of ZnO were studied. The products were characterized by XRD and SEM. The results showed that ZnO powder was of hexagonal wurtzite structure and well crystallized with high purity. Floc content and caramel pigment concentration played an important role in the final morphologies of ZnO nanowires. On the basis of these results, a possible growth mechanism for the formation of ZnO nanowires was described. These findings not only may contribute to control the synthesis of ZnO, but also present a novel method for the disposal of wastewater treatment sludge. PMID:23882849

Li, Xiaolong; Zhang, Fengqin; Ma, Chao; Elingarami, Sauli; He, Nongyue

2013-08-01

77

Stability of expanded granular sludge bed process for terylene artificial silk printing and dyeing wastewater treatment.  

PubMed

Terylene artificial silk printing and dyeing wastewater (TPD wastewater), containing averaged 710 mg/L terephthalic acid(TA) as the main carbon source and the character pollutant, was subjected to expanded granular sludge bed (EGSB) process. The stability of the EGSB process was firstly conducted by laboratory experiment. TA ionization was the predominated factor influencing the acid-base balance of the system. High concentration of TA in wastewater resulted in sufficient buffering capacity to neutralize the volatile fatty acids (VFA) generated from substrate degradation and provided strong base for anaerobic system to resist the pH decrease below 6.5. VFA and UFA caused almost no inhibition on the anaerobic process and biogas production except that pH was below 6.35 and VFA was at its maximum value. Along with the granulating of the activated sludge, the efficiency of organic removal and production rate of biogas increased gradually and became more stable. After start-up, the efficiency of COD removal increased to 57%-64%, pH stabilized in a range of 7.99-8.04, and production rate of biogas was relatively high and stable. Sludge granulating, suitable influent of pH and loading were responsible for the EGSB stability. The variation of VFA concentration only resulted in neglectable rebound of pH, and the inhibition from VFA could be ignored in EGSB. The EGSB reactor was stable for TPD wastewater treatment. PMID:16083115

Guan, Bao-Hong

2005-01-01

78

Comparison of Control Strategies for Dissolved Oxygen Control in Activated Sludge Wastewater Treatment Process  

Microsoft Academic Search

Six control strategies; PID control, Model Predictive Control (MPC) with linear model, MPC with non-linear model, Nonlinear Autoregressive-Moving Average (NARMA-L2) control, Neural Network Model Predictive Control (NN-MPC) and optimal control with sequential quadratic programming (SQP) algorithm were evaluated via simulation of activated sludge wastewater treatment process. Controller performance assessment was based on rise time, overshoot, Integral Absolute Error (IAE) and

Evrim Akyurek; Mehmet Yuceer; Ilknur Atasoy; Ridvan Berber

2009-01-01

79

Status of Oxygen-Activated Sludge Wastewater Treatment.  

National Technical Information Service (NTIS)

This publication provides an updated status report on the number and type of oxygen-activated sludge facilities in operation, under construction, and being designed. It describes in detail the latest EPA supported oxygenation research and demonstration pr...

1977-01-01

80

Concentrations of trace substances in sewage sludge from 28 wastewater treatment works in the UK.  

PubMed

Concentrations of trace substances in sewage sludge have been measured in a survey of 28 wastewater treatment works (WwTWs) in the UK carried out over a period of 12months. Approximately 250 samples were analysed for more than 40 trace contaminants, including trace metals, pharmaceuticals, polycyclic aromatic hydrocarbons (PAHs), 'emerging' and regulated organic pollutants. All substances investigated were found to be present in at least some of the sludges sampled. Concentrations were relatively homogenous across all the WwTWs, irrespective of the treatment process, influent and effluent concentrations, and the location of the sludge sampling point within each works. Analysis of the results against existing regulatory and proposed thresholds suggested that levels are mostly below the limits set in the Sewage Sludge Directive, and proposed new limits for sludge used in agriculture. Predicted soil concentrations after application of sewage sludge to land were below the predicted no effect concentrations (PNEC) for all determinands. Predicted concentrations of pharmaceuticals in soil were also below thresholds deemed to indicate negligible environmental risk. PMID:24997955

Jones, Vera; Gardner, Mike; Ellor, Brian

2014-09-01

81

Metaproteomics Provides Functional Insight into Activated Sludge Wastewater Treatment  

PubMed Central

Background Through identification of highly expressed proteins from a mixed culture activated sludge system this study provides functional evidence of microbial transformations important for enhanced biological phosphorus removal (EBPR). Methodology/Principal Findings A laboratory-scale sequencing batch reactor was successfully operated for different levels of EBPR, removing around 25, 40 and 55 mg/l P. The microbial communities were dominated by the uncultured polyphosphate-accumulating organism “Candidatus Accumulibacter phosphatis”. When EBPR failed, the sludge was dominated by tetrad-forming ?-Proteobacteria. Representative and reproducible 2D gel protein separations were obtained for all sludge samples. 638 protein spots were matched across gels generated from the phosphate removing sludges. 111 of these were excised and 46 proteins were identified using recently available sludge metagenomic sequences. Many of these closely match proteins from “Candidatus Accumulibacter phosphatis” and could be directly linked to the EBPR process. They included enzymes involved in energy generation, polyhydroxyalkanoate synthesis, glycolysis, gluconeogenesis, glycogen synthesis, glyoxylate/TCA cycle, fatty acid ? oxidation, fatty acid synthesis and phosphate transport. Several proteins involved in cellular stress response were detected. Conclusions/Significance Importantly, this study provides direct evidence linking the metabolic activities of “Accumulibacter” to the chemical transformations observed in EBPR. Finally, the results are discussed in relation to current EBPR metabolic models.

Wilmes, Paul; Wexler, Margaret; Bond, Philip L.

2008-01-01

82

Atomized sludges via spray-drying at low temperatures: an alternative to conventional wastewater treatment plants.  

PubMed

Removal of sludges from Wastewater Treatment Plants (WWTP) represents a serious worldwide environmental problem for which alternatives other than their simple incineration are investigated. In this work the treatment of raw sludge from urban WWTP by means of a minimization process through spray-drying is analyzed as well as some proposals for revaluating the resulting dry product. Analysis is supported by some experimental results obtained with a laboratory spray dryer. The experimental procedure at laboratory scale is extrapolated to an industrial plant scale. An economic analysis of the proposal in relation to other possible sludge treatments is presented, taking into account in this case the comparison between the costs of the processes of sludge thickening, stabilization and dehydratation and the costs of spray-drying (especially power consumption), minimization of the final waste and reuse options. Finally, an environmental balance of the process is presented. In contrast with the classical treatment line, this alternative allows transforming sludges, i.e., a waste, into a valuable product with several applications. PMID:22525834

Cusidó, Joan A; Cremades, Lázaro V

2012-08-30

83

Bulking control by low-dose ozonation of returned activated sludge in a full-scale wastewater treatment plant.  

PubMed

Sludge bulking is still a problem in the operation of state-of-the-art wastewater treatment plants (WWTPs). The ozonation of returned activated sludge (RAS) is an innovative option as a non-specific measure for the control of filament growth. The applicability of sludge ozonation for bulking control of a large wastewater treatment plant was investigated. At a full-scale WWTP one lane was equipped with a sludge ozonation plant for RAS. The implemented sludge ozonation of RAS was tested against the two identical references lanes of the same WWTP. The positive effect on settleability could be clearly proven. Low-dose sludge ozonation could be a technical alternative in comparison with the established chemical measures for bulking control. PMID:22508129

Lyko, S; Teichgräber, B; Kraft, A

2012-01-01

84

Mercury mass balance at a wastewater treatment plant employing sludge incineration with offgas mercury control.  

PubMed

Efforts to reduce the deliberate use of mercury (Hg) in modern industrialized societies have been largely successful, but the minimization and control of Hg in waste streams are of continuing importance. Municipal wastewater treatment plants are collection points for domestic, commercial, and industrial wastewaters, and Hg removal during wastewater treatment is essential for protecting receiving waters. Subsequent control of the Hg removed is also necessary to preclude environmental impacts. We present here a mass balance for Hg at a large metropolitan wastewater treatment plant that has recently been upgraded to provide for greater control of the Hg entering the plant. The upgrade included a new fluidized bed sludge incineration facility equipped with activated carbon addition and baghouse carbon capture for the removal of Hg from the incinerator offgas. Our results show that Hg discharges to air and water from the plant represented less than 5% of the mass of Hg entering the plant, while the remaining Hg was captured in the ash/carbon residual stream exiting the new incineration process. Sub-optimum baghouse operation resulted in some of the Hg escaping collection there and accumulating with the ash/carbon particulate matter in the secondary treatment tanks. Overall, the treatment process is effective in removing Hg from wastewater and sequestering it in a controllable stream for secure disposal. PMID:17888493

Balogh, Steven J; Nollet, Yabing H

2008-01-15

85

Metagenomic analysis of sludge from full-scale anaerobic digesters operated in municipal wastewater treatment plants.  

PubMed

This study applied Illumina high-throughput sequencing to explore the microbial communities and functions in anaerobic digestion sludge (ADS) from two wastewater treatment plants based on a metagenomic view. Taxonomic analysis using SILVA SSU database indicated that Proteobacteria (9.52-13.50 %), Bacteroidetes (7.18 %-10.65 %) and Firmicutes (7.53 %-9.46 %) were the most abundant phyla in the ADS. Differences of microbial communities between the two types of ADS were identified. Genera of Methanosaeta and Methanosarcina were the major methanogens. Functional analysis by SEED subsystems showed that the basic metabolic functions of metagenomes in the four ADS samples had no significant difference among them, but they were different from other microbial communities from activated sludge, human faeces, ocean and soil. Abundances of genes in methanogenesis pathway were also quantified using a methanogenesis genes database extracted from KEGG. Results showed that acetotrophic was the major methanogenic pathway in the anaerobic sludge digestion. PMID:24633414

Yang, Ying; Yu, Ke; Xia, Yu; Lau, Frankie T K; Tang, Daniel T W; Fung, Wing Cheong; Fang, Herbert H P; Zhang, Tong

2014-06-01

86

Polychlorinated naphthalenes in sewage sludge from wastewater treatment plants in China.  

PubMed

Polychlorinated naphthalenes (PCNs) were nominated as persistent organic pollutants candidate in the Stockholm Convention in 2011. In this study, the profiles, concentrations and spatial distributions of PCNs were analyzed in 30 sewage sludge samples from wastewater treatment plants (WWTPs) in China. Concentrations of ?75PCNs in sludge samples were in the range of 1.05-10.9ng/g dry weight (dw) with a mean value of 3.98ng/gdw. The predominant homologues in the sludge were mono- to tetra-CNs, accounting for approximately 85% of total PCNs. The total toxic equivalent quantities (TEQs) of dioxin-like PCN congeners ranged from 0.04 to 2.28pg/gdw with a mean value of 0.36pg/gdw, which were lower than the maximum permissible TEQ concentrations in sludge for land application in China. Levels of PCNs and TEQs in sludge were relatively higher in samples from highly industrialized and developed cities in eastern China, implying a possible link between PCN contamination and the local economic development, but more studies are warranted to corroborate this. Industrial sources might be important contributors of PCNs to sewage sludge in China. PMID:24880545

Zhang, Haiyan; Xiao, Ke; Liu, Jiyan; Wang, Thanh; Liu, Guorui; Wang, Yawei; Jiang, Guibin

2014-08-15

87

Monitoring Precursor 16S rRNAs of Acinetobacter spp. in Activated Sludge Wastewater Treatment Systems  

PubMed Central

Recently, Cangelosi and Brabant used oligonucleotide probes targeting the precursor 16S rRNA of Escherichia coli to demonstrate that the levels of precursor rRNA were more sensitive to changes in growth phase than the levels of total rRNA (G. A. Cangelosi and W. H. Brabant, J. Bacteriol. 179:4457–4463, 1997). In order to measure changes in the levels of precursor rRNA in activated sludge systems, we designed oligonucleotide probes targeting the 3? region of the precursor 16S rRNA of Acinetobacter spp. We used these probes to monitor changes in the level of precursor 16S rRNA during batch growth of Acinetobacter spp. in Luria-Bertani (LB) medium, filtered wastewater, and in lab- and full-scale wastewater treatment systems. Consistent with the previous reports for E. coli, results obtained with membrane hybridizations and fluorescence in situ hybridizations with Acinetobacter calcoaceticus grown in LB medium showed a more substantial and faster increase in precursor 16S rRNA levels compared to the increase in total 16S rRNA levels during exponential growth. Diluting an overnight culture of A. calcoaceticus grown in LB medium with filtered wastewater resulted in a pattern of precursor 16S rRNA levels that appeared to follow diauxic growth. In addition, fluorescence in situ hybridizations with oligonucleotide probes targeting total 16S rRNA and precursor 16S rRNA showed that individual cells of A. calcoaceticus expressed highly variable levels of precursor 16S rRNA when adapting from LB medium to filtered sewage. Precursor 16S rRNA levels of Acinetobacter spp. transiently increased when activated sludge was mixed with influent wastewater in lab- and full-scale wastewater treatment systems. These results suggest that Acinetobacter spp. experience a change in growth activity within wastewater treatment systems.

Oerther, Daniel B.; Pernthaler, Jakob; Schramm, Andreas; Amann, Rudolf; Raskin, Lutgarde

2000-01-01

88

STATUS OF OXYGEN-ACTIVATED SLUDGE WASTEWATER TREATMENT  

EPA Science Inventory

This publication provides an updated status report on the number and type of oxygen-activated sludge facilities in operation, under construction, and being designed. It describes in detail the latest EPA supported oxygenation research and demonstration project, an evaluation of t...

89

Reduction in excess sludge production in a dairy wastewater treatment plant via nozzle-cavitation treatment: case study of an on-farm wastewater treatment plant.  

PubMed

Nozzle-cavitation treatment was used to reduce excess sludge production in a dairy wastewater treatment plant. During the 450-d pilot-scale membrane bioreactor (MBR) operation, when 300 l of the sludge mixed liquor (1/10 of the MBR volume) was disintegrated per day by the nozzle-cavitation treatment with the addition of sodium hydrate (final concentration: 0.01% W/W) and returned to the MBR, the amount of excess sludge produced was reduced by 80% compared with that when sludge was not disintegrated. On the basis of the efficiency of CODCr removal and the ammonia oxidation reaction, it was concluded that the nozzle-cavitation treatment did not have a negative impact on the performance of the MBR. The estimation of the inorganic material balance showed that when the mass of the excess sludge was decreased, the inorganic content of the activated sludge increased and some part of the inorganic material was simultaneously solubilized in the effluent. PMID:19246193

Hirooka, Kayako; Asano, Ryoki; Yokoyama, Atsushi; Okazaki, Masao; Sakamoto, Akira; Nakai, Yutaka

2009-06-01

90

LAND TREATMENT FIELD STUDIES. VOLUME 5. WASTEWATER TREATMENT SLUDGE FROM BATCH ORGANIC CHEMICAL SYNTHESIS  

EPA Science Inventory

This report presents the results of field measurements and observations of a land treatment operation using a sludge generated from organic chemical manufacture. The sludge is applied to a turf farm which contains acidic soil; the sludge reduces the lime addition requirements for...

91

Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment.  

PubMed

Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics parameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the moderate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (K(S)) were 0.0208-0.0642 L/(gMLSS).h and 0.44-0.59 (gCOD)/L respectively at 20 degrees C-35 degrees C. Activation energy (E(a)) was 6.05 x 10(4) J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment. PMID:14994435

Guan, Bao-hong; Wu, Zhong-biao; Xu, Gen-liang

2004-04-01

92

Treatment of thiosulfate-containing wastewater in activated sludge systems  

SciTech Connect

Simultaneous biological oxidation of sodium thiosulfate and organic carbon was studied in continuous bench-scale activated sludge reactors. Thiosulfate oxidation did not influence organic carbon removal, which was more than 90%. Hydraulic detention time, pH, and nitrogen and phosphorus concentrations did not influence elemental sulfur production or conversion of thiosulfate to sulfate. The thiosulfate F:M was the only determinant parameters. Thiobacillus concentrations were ten thousand bacteria per milliliter of mixed liquor. Nitrification and sludge bulking were not affected. Thiosulfate was chemically stable between pH 4.9 and 9.2 in batch experiments. Because continuous reactor pH was 5.6 to 7.9, thiosulfate removal was assumed to be biologically mediated. 21 references.

Millano, E.F.; Sorber, C.A.

1986-09-01

93

EVALUATION OF HEALTH RISKS ASSOCIATED WITH WASTEWATER TREATMENT AND SLUDGE COMPOSTING  

EPA Science Inventory

The investigation included (1) a prospective study of wastewater sludge compost workers, (2) serologic analyses of wastewater-exposed workers, (3) a mortality study of former wastewater employees, and (4) chemical analyses of specimens from a population whose drinking water was c...

94

A comparative study of freeze-thaw processes for conditioning wastewater and water treatment sludges  

Microsoft Academic Search

This research effort involved the application of indirect- and direct-contact, freeze-thaw conditioning techniques for improving the dewatering characteristics of both waste water and water treatment sludges. Sludges tested included waste activated sludge, primary sewage sludge, waste activated\\/primary sewage sludge mixtures and alum sludge. The direct-freeze methods examined were the use of a secondary refrigerant (butane) evaporated in the sludge and

Trahern

1989-01-01

95

Physico-chemical pre-treatment and biotransformation of wastewater and wastewater sludge--fate of bisphenol A.  

PubMed

Bisphenol A (BPA), an endocrine disrupting compound largely used in plastic and paper industry, ends up in aquatic systems via wastewater treatment plants (WWTPs) among other sources. The identification and quantification of BPA in wastewater (WW) and wastewater sludge (WWS) is of major interest to assess the endocrine activity of treated effluent discharged into the environment. Many treatment technologies, including various pre-treatment methods, such as hydrolysis, Fenton oxidation, peroxidation, ultrasonication and ozonation have been developed in order to degrade BPA in WW and WWS and for the production of WWS based value-added products (VAPs). WWS based VAPs, such as biopesticides, bioherbicides, biofertilizers, bioplastics and enzymes are low cost biological alternatives that can compete with chemicals or other cost intensive biological products in the current markets. However, this field application is disputable due to the presence of these organic compounds which has been discussed with a perspective of simultaneous degradation. The pre-treatment produces an impact on rheology as well as value-addition which has been reviewed in this paper. Various analytical techniques available for the detection of BPA in WW and WWS are also discussed. Presence of heavy metals and possible thermodynamical behavior of the compound in WW and WWS can have major impact on BPA removal, which is also included in the review. PMID:20083294

Mohapatra, D P; Brar, S K; Tyagi, R D; Surampalli, R Y

2010-02-01

96

Distribution of phosphorus, copper and zinc in activated sludge treatment process of swine wastewater.  

PubMed

Changes in swine wastewater chemical features during an activated sludge treatment process were surveyed on 11 farms, and analyzed with non-biodegradable elements, i.e., phosphorus (P), copper (Cu), and zinc (Zn). In piggery wastewater, they were linearly correlated with suspended solid (SS) concentrations and the major portion was in solid fractions. After the pretreatment step, they were removed, with 80% for total P, 85% for total Cu, and 84% for total Zn. After the activated sludge process, total P, Cu, and Zn were then removed at 83%, 96%, and 95%, respectively. Removing SS thoroughly at each step was shown to be the most important factor in preventing outflow of these elements, since there are linear correlations or a positive relationship between the removal of SS concentrations and their removal in solid form. Most of the P, Cu, and Zn in activated sludge effluent was in soluble form, and the concentrations of Cu and Zn in the effluent were low enough, while further P removal might be required. PMID:20667713

Suzuki, Kazuyoshi; Waki, Miyoko; Yasuda, Tomoko; Fukumoto, Yasuyuki; Kuroda, Kazutaka; Sakai, Takahiro; Suzuki, Naoto; Suzuki, Ryoji; Matsuba, Kenji

2010-12-01

97

Partitioning, Persistence, and Accumulation in Digested Sludge of the Topical Antiseptic Triclocarban During Wastewater Treatment  

PubMed Central

The topical antiseptic agent triclocarban (TCC) is a common additive in many antimicrobial household consumables, including soaps and other personal care products. Long-term usage of the mass-produced compound and a lack of understanding of its fate during sewage treatment motivated the present mass balance analysis conducted at a typical U.S. activated sludge wastewater treatment plant featuring a design capacity of 680 million liters per day. Using automated samplers and grab sampling, the mass of TCC contained in influent, effluent and digested sludge was monitored by isotope dilution liquid chromatography (tandem) mass spectrometry. The average mass of TCC (mean ± standard deviation) entering and exiting the plant in influent (6.1 ± 2.0 ?g/L) and effluent (0.17 ± 0.03 ?g/L) was 3,737 ± 694 and 127 ± 6 g/d, respectively, indicating an aqueous-phase removal efficiency of 97 ± 1%. Tertiary treatment by chlorination and sand filtration provided no detectable benefit to the overall removal. Due to strong sorption of TCC to wastewater particulate matter (78 ± 11% sorbed), the majority of the TCC mass was sequestered into sludge in the primary and secondary clarifiers of the plant. Anaerobic digestion for 19 days did not promote TCC transformation, resulting in an accumulation of the antiseptic compound in dewatered, digested municipal sludge to levels of 51 ± 15 mg/kg dry weight (2,815 ± 917 g/d). In addition to the biocide mass passing through the plant contained in the effluent (3 ± 1%), 76 ± 30% of the TCC input entering the plant underwent no net transformation and instead partitioned into and accumulated in municipal sludge. Based on the rate of beneficial reuse of sludge produced by this facility (95%), which exceeds the national average (63%), study results suggest that approximately three quarters of the mass of TCC disposed of by consumers in the catchment area of the plant ultimately is released into the environment by application of municipal sludge (biosolids) on land used in part for agriculture.

Heidler, Jochen; Sapkota, Amir; Halden, Rolf U.

2009-01-01

98

Partitioning, persistence, and accumulation in digested sludge of the topical antiseptic triclocarban during wastewater treatment.  

PubMed

The topical antiseptic agent triclocarban (TCC) is a common additive in many antimicrobial household consumables, including soaps and other personal care products. Long-term usage of the mass-produced compound and a lack of understanding of its fate during sewage treatment motivated the present mass balance analysis conducted at a typical U.S. activated sludge wastewater treatment plant featuring a design capacity of 680 million liters per day. Using automated samplers and grab sampling, the mass of TCC contained in influent, effluent, and digested sludge was monitored by isotope dilution liquid chromatography (tandem) mass spectrometry. The average mass of TCC (mean +/- standard deviation) entering and exiting the plant in influent (6.1 +/- 2.0 microg/L) and effluent (0.17 +/- 0.03 microg/ L) was 3737 +/- 694 and 127 +/- 6 g/d, respectively, indicating an aqueous-phase removal efficiency of 97 +/- 1%. Tertiary treatment by chlorination and sand filtration provided no detectable benefit to the overall removal. Due to strong sorption of TCC to wastewater particulate matter (78 +/- 11% sorbed), the majority of the TCC mass was sequestered into sludge in the primary and secondary clarifiers of the plant. Anaerobic digestion for 19 days did not promote TCC transformation, resulting in an accumulation of the antiseptic compound in dewatered, digested municipal sludge to levels of 51 +/- 15 mg/kg dry weight (2815 +/- 917 g/d). In addition to the biocide mass passing through the plant contained in the effluent (3 +/- 1%), 76 +/- 30% of the TCC input entering the plant underwent no net transformation and instead partitioned into and accumulated in municipal sludge. Based on the rate of beneficial reuse of sludge produced by this facility (95%), which exceeds the national average (63%), study results suggest that approximately three-quarters of the mass of TCC disposed of by consumers in the sewershed of the plant ultimately is released into the environment by application of municipal sludge (biosolids) on land used in part for agriculture. PMID:16786704

Heidler, Jochen; Sapkota, Amir; Halden, Rolf U

2006-06-01

99

Net energy production and emissions mitigation of domestic wastewater treatment system: a comparison of different biogas-sludge use alternatives.  

PubMed

Wastewater treatment systems are increasingly designed for the recovery of valuable chemicals and energy in addition to waste stream disposal. Herein, the life-cycle energy production and emissions mitigation of a typical domestic wastewater treatment system were assessed, in which different combinations of biogas use and sludge processing lines for industrial or household applications were considered. The results suggested that the reuse of biogas and sludge was so important in the system's overall energy balance and environmental performance that it may offset the cost in the plant's installation and operation. Combined heat and power and household utilization were two prior options for net energy production, provided an ideal power conversion efficiency and biogas production. The joint application of household biogas use and sludge nutrient processing achieved both high net energy production and significant environmental remediation across all impact categories, representing the optimal tradeoff for domestic wastewater treatment. PMID:23880131

Chen, Shaoqing; Chen, Bin

2013-09-01

100

Treatment of biomass gasification wastewater using a combined wet air oxidation/activated sludge process  

SciTech Connect

A lab-scale treatability study for using thermal and biological oxidation to treat a biomass gasification wastewater (BGW) having a chemical oxygen demand (COD) of 46,000 mg/l is described. Wet air oxidation (WA0) at 300/sup 0/C and 13.8 MPa (2000 psi) was used to initially treat the BGW and resulted in a COD reduction of 74%. This was followed by conventional activated sludge treatment using operating conditions typical of municipal sewage treatment plants. This resulted in an additional 95% COD removal. Overall COD reduction for the combined process was 99%. A detailed chemical analysis of the raw BGW and thermal and biological effluents was performed using gas chromatography/mass spectrometry (GC/MS). These results showed a 97% decrease in total extractable organics with WA0 and a 99.6% decrease for combined WA0 and activated sludge treatment. Components of the treated waters tended to be fewer in number and more highly oxidized. An experiment was conducted to determine the amount of COD reduction caused by volatilization during biological treatment. Unfortunately, this did not yield conclusive results. Treatment of BGW using WA0 followed by activated sludge appears to be very effective and investigations at a larger scale are recommended.

English, C.J.; Petty, S.E.; Sklarew, D.S.

1983-02-01

101

Effect of wastewater treatment processes on the pyrolysis properties of the pyrolysis tars from sewage sludges  

NASA Astrophysics Data System (ADS)

The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, those from the activated sludge process and the indigested sludge from the continuous SBR process respectively, were studied by thermal gravimetric analysis at a heating rate of 10 °C/min in the nitrogen atmosphere. The results show that the pyrolysis processes of the pyrolysis tars of 1#, 2#, 3# and 5# all can be divided into four stages: the stages of light organic compounds releasing, heavy polar organic compounds decomposition, heavy organic compounds decomposition and the residual organic compounds decomposition. However, the process of 4# pyrolysis tar is only divided into three stages: the stages of light organic compounds releasing, decomposition of heavy polar organic compounds and the residual heavy organic compounds respectively. Both the sludge anaerobic digestion and the "anaerobic" process in wastewater treatment processes make the content of light organic compounds in tars decrease, but make that of heavy organic compounds with complex structure increase. Besides, both make the pyrolysis properties of the tars become worse. The pyrolysis reaction mechanisms of the five pyrolysis tars have been studied with Coats-Redfern equation. It shows that there are the same mechanism functions in the first stage for the five tars and in the second and third stage for the tars of 1#, 2#, 3# and 5#, which is different with the function in the second stage for 4# tar. The five tars are easy to volatile.

Wu, Xia; Xie, Li-Ping; Li, Xin-Yu; Dai, Xiao-Hong; Fei, Xue-Ning; Jiang, Yuan-Guang

2011-06-01

102

Occurrence of organic contaminants in sewage sludges from eleven wastewater treatment plants, China.  

PubMed

This study presents the occurrence of 43 semi-volatile organic compounds (SVOCs) listed as priority pollutants by both China and the United States Environmental Protection Agency, in sewage sludges collected from eleven wastewater treatment plants (WWTPs) of mainland and Hong Kong, China. Thirty-six SVOCs were detected by gas chromatography coupled with mass spectrometer (GC-MS) and at least 14 in each sample. The most abundant compounds were phthalic acid esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) with total concentrations ranging from 10 to 114mgkg(-1) dry weight (d.w.) (with a mean of 30mgkg(-1) d.w.) and from 1.4 to 33mgkg(-1)d.w. (with a mean of 16mgkg(-1) d.w.), respectively, followed by chlorobenzenes, nitroaromatics, haloethers and halogenated hydrocarbons which occurred generally at concentrations lower than 10mgkg(-1) d.w. Large variations were observed between the concentrations of individual compounds as well as their total concentrations in sludge samples from different WWTPs. The highest values of sum concentration of 16 PAHs and of 6 PAEs were found in sewage sludge from Beijing. The mean total concentration of each class of SVOCs in sewage sludge from mainland was remarkably higher than that from Hong Kong. The concentrations of di(2-ethylhexyl) phthalate in 91% sludge samples met the limit (100mgkg(-1)d.w.) proposed by the Europe Union for land application, whereas the PAH concentrations of 64% sludge samples exceeded the maximum permissible concentration (6.0mgkg(-1)d.w.). The occurrence of SVOCs in this study are compared with other studies and their sources are discussed. PMID:17509650

Cai, Quan-Ying; Mo, Ce-Hui; Wu, Qi-Tang; Zeng, Qiao-Yun; Katsoyiannis, Athanasios

2007-08-01

103

Effect of variability on the treatment of textile dyeing wastewater by activated sludge  

Microsoft Academic Search

Using a pilot scale continuous system with activated sludge, the effect of the variability of non-pretreated synthetic textile wastewater containing reactive dyes on the pollution bio-removal and on the characteristics of activated sludge (sludge volume index, floc size and shape, filamentous bacteria abundance) has been monitored. Off-line batch respirometry tests have been used in parallel to assess the toxic effects

A. Alinsafi; M. da Motta; S. Le Bonté; M. N. Pons; A. Benhammou

2006-01-01

104

Health effects associated with wastewater treatment and disposal. [Wastewater treatment  

Microsoft Academic Search

A literature review dealing with the health hazards associated with working in wastewater treatment plants and those hazards to the general public from land disposal of wastewater and sludge is presented. Specific areas reviewed include the health effects associated with the incineration and composting of sludge, aquaculture, and various onsite systems of wastewater treatment. The presence of organic chemicals, inorganic

N. E. Kowal; H. R. Pahren

1982-01-01

105

FRACTIONATION OF MUTAGENS FROM MUNICIPAL SLUDGE AND WASTEWATER  

EPA Science Inventory

There are potential environmental concerns from the disposal of municipal wastewater effluents and sewage treatment plant sludges. This report summarizes the microbial mutagenic evaluation and chemical analysis of 13 sewage sludge samples from various sewage treatment plants loca...

106

Full scale fluidized bed anaerobic reactor for domestic wastewater treatment: performance, sludge production and biofilm.  

PubMed

This paper describes the performance, sludge production and biofilm characteristics of a full scale fluidized bed anaerobic reactor (32 m3) for domestic wastewater treatment. The reactor was operated with 10.5 m x h(-1) upflow velocity, 3.2 h hydraulic retention time, and recirculation ratio of 0.85 and it presented removal efficiencies of 71+/-8% of COD and 77+/-14% of TSS. During the apparent steady-state period, specific sludge production and sludge age in the reactor were (0.116+/-0.033) kgVSS. kgCOD(-1) and (12+/-5)d, respectively. Biofilm formed in the reactor presented two different patterns: one of them at the beginning of the colonization and the other of mature biofilm. These different colonization patterns are due to bed stratification in the reactor, caused by the difference in local-energy dissipation rates along the reactor's height, and density, shape, etc. of the bioparticles. The biofilm population is formed mainly of syntrophic consortia among sulfate reducing bacteria, methanogenic archaea such as Methanobacterium and Methanosaeta-like cells. PMID:15303757

Mendonça, N M; Niciura, C L; Gianotti, E P; Campos, J R

2004-01-01

107

EFFECT OF AN ACTIVATED SLUDGE WASTEWATER TREATMENT PLANT ON AMBIENT AIR DENSITIES OF AEROSOLS CONTAINING BACTERIA AND VIRUSES  

EPA Science Inventory

Bacteria and virus-containing aerosols were studied during late summer and fall in a U.S. midwestern suburb before and during the start up and operation of an unenclosed activated sludge wastewater treatment plant. The air in this suburban area contained low-level densities of in...

108

Essence of disposing the excess sludge and optimizing the operation of wastewater treatment: rheological behavior and microbial ecosystem.  

PubMed

Proper disposal of excess sludge and steady maintenance of the high bioactivity of activated sludge in bioreactors are essential for the successful operation of wastewater treatment plants (WWTPs). Since sludge is a non-Newtonian fluid, the rheological behavior of sludge can therefore have a significant impact on various processes in a WWTP, such as fluid transportation, mixing, oxygen diffusion, mass transfer, anaerobic digestion, chemical conditioning and mechanical dewatering. These are key factors affecting the operation efficiency and the energy consumption of the entire process. In the past decade-due to the production of large quantities of excess sludge associated with the extensive construction of WWTPs and the emergence of some newly-developed techniques for wastewater purification characterized by high biomass concentrations-investigations into the rheology of sludge are increasingly important and this topic has aroused considerable interests. We reviewed a number of investigations into the rheology of sludge, with the purpose of providing systematic and detailed analyses on the related aspects of the rheological behavior of sludge. It is clear that, even though considerable research has focused on the rheology of sludge over a long time period, there is still a need for further thorough investigation into this field. Due to the complex process of bio-treatment in all WWTPs, biological factors have a major influence on the properties of sludge. These influences are however still poorly understood, particularly with respect to the mechanisms involved and magnitude of such impacts. When taking note of the conspicuous biological characteristics of sludge, it becomes important that biological factors, such as the species composition and relative abundance of various microorganisms, as well as the microbial community characteristics that affect relevant operating processes, should be considered. PMID:24462086

Tang, Bing; Zhang, Zi

2014-06-01

109

Bacterial community dynamics in a full-scale municipal wastewater treatment plant employing conventional activated sludge process.  

PubMed

To elucidate the bacterial community dynamics in a full-scale wastewater treatment plant (WWTP) and the relatedness among bacterial communities in the influent, effluent and sludge, the structure and metabolic ability of the bacterial community throughout a full-scale WWTP employing a conventional activated sludge process was investigated during a period of 10 months. The bacterial community structure was analyzed by terminal-restriction fragment length polymorphism targeting eubacterial 16S rRNA genes, while a Biolog assay was applied to assess the metabolic ability of the activated sludge. Influent bacterial community structure was generally stable. In contrast, the bacterial community structure in the effluent was similar to that in the influent in some cases, while in other cases it was unique and differed greatly from that in the influent and sludge. These results suggest that temporal variations of the effluent bacterial community may be useful to predict the wastewater treatment performance and settleability of activated sludge. The bacterial community structure in the sludge was relatively stable and was rarely impacted by the influent populations. Biolog assay also revealed that activated sludge maintained a remarkably similar metabolic potential of organic compounds over time due to functional redundancy, in which the minor populations played a significant role. PMID:24480747

Hashimoto, Kurumi; Matsuda, Masami; Inoue, Daisuke; Ike, Michihiko

2014-07-01

110

Dairy wastewater treatment using an activated sludge-microalgae system at different light intensities.  

PubMed

A microalgae-bacteria system was used for dairy industry wastewater treatment in sequenced batch mode in a photobioreactor. The research investigated the influence of two light intensities: 360 and 820 ?mol m(-2)s(-1) on treatment performances, microalgal cell recovery and dynamics of the protozoan community. Results showed that the light intensity of 360 ?mol m(-2)s(-1) was found to be insufficient to support photosynthetic activity after the increase of bacterial biomass leading to the decrease of organic matter and ammonium removal efficiencies from 95 to 78% and 95 to 41%, respectively. Maximum microalgal cells recovery was about 63%. Continuous modification in the protozoan community was also noticed during this test. Increasing the light intensity to 820 ?mol m(-2)s(-1) led to better microalgal cells recovery (up to 88%) and improved treatment performances. However, the decrease of protozoan richness to small flagellates and free-swimming ciliates was noticed. Moreover, the developed protozoan trophic network was found to be different from that identified in the conventional activated sludge system. The study emphasized that high increase of bacterial biomass promoted in nutrient- and organic matter-rich wastewater can strongly affect the treatment performances as a result of the shadow effect produced on the photoautotrophic microalgae aggregates. PMID:24759517

Tricolici, O; Bumbac, C; Patroescu, V; Postolache, C

2014-01-01

111

Ozonation effects for excess sludge reduction on bacterial communities composition in a full-scale activated sludge plant for domestic wastewater treatment.  

PubMed

Activated sludge process is the most widely diffused system to treat wastewater to control the discharge of pollutants into the environment. Microorganisms are responsible for the removal of organic matter, nitrogen, phosphorous and other emerging contaminants. The environmental conditions of biological reactors significantly affects the ecology of the microbial community and, therefore, the performance of the treatment process. In the last years, ozone has been used to reduce excess sludge production by wastewater treatment plants (WWTPs), whose disposal represents one of the most relevant operational costs. The ozonation process has demonstrated to be a viable method to allow a consistent reduction in excess sludge. This study was carried out in a full-scale plant treating municipal wastewater in two parallel lines, one ozonated in the digestion tank and another used as a control. Bacterial communities of samples collected from both lines of digestion thanks were then compared to assess differences related to the ozonation treatment. Data were then analysed with terminal restriction fragment length polymorphism (T-RFLP) analysis on 16S rRNA gene. Differences between bacterial communities of both treated and untreated line appeared 2 weeks after the beginning of the treatment. Results demonstrated that ozonation treatment significantly affected the activated sludge in WWTP. PMID:24701944

Chiellini, C; Gori, R; Tiezzi, A; Brusetti, L; Pucciarelli, S; D'Amato, E; Chiavola, A; Sirini, P; Lubello, C; Petroni, G

2014-01-01

112

Selenium Speciation in Biofilms from Granular Sludge Bed Reactors Used for Wastewater Treatment  

NASA Astrophysics Data System (ADS)

Se K-edge XAFS spectra were collected for various model compounds of Se as well as for 3 biofilm samples from bioreactors used for Se-contaminated wastewater treatment. In the biofilm samples, Se is dominantly as Se(0) despite Se K-edge XANES spectroscopy cannot easily distinguish between elemental Se and Se(-I)-bearing selenides. EXAFS spectra indicate that Se is located within aperiodic domains, markedly different to these known in monoclinc red selenium. However, Se can well occur within nanodivided domains related to monoclinic red Se, as this form was optically observed at the rim of some sludges. Aqueous selenate is then efficiently bioreduced, under sulfate reducing and methanogenic conditions.

van Hullenbusch, Eric; Farges, François; Lenz, Markus; Lens, Piet; Brown, Gordon E.

2007-02-01

113

A review and assessment of emerging technologies for the minimization of excess sludge production in wastewater treatment plants.  

PubMed

This paper focuses on the most promising technologies, available for full-scale applications, aimed to the on-site reduction of the excess sludge produced in municipal wastewater treatment plants. New techniques are added to the conventional stages of wastewater treatment, both integrated in the activated sludge bioreactors or applied as pretreatment for the enhancement of anaerobic digestion. A concise review about the alternatives based on physical, chemical or biological mechanisms is described. The present work highlights the efficiency of two such techniques, sonolysis and alkaline thermolysis integrated on the return flow from the secondary settler into the activated sludge bioreactors. The investigation on the effect of sonolysis and alkaline thermolysis on activated sludge samples was carried out by evaluating the COD concentration released in soluble and colloidal form and biodegradability measured by respirometry. The physicochemical treatments of sludge have several advantages (easy management, stability in performances and flexibility), but are associated with high operational costs that often limit the wide-scale applications. The application of hybrid methods, that couple almost two techniques for the enhancement of efficiency with respect to a single one, could optimise the sludge reduction, giving a significant saving in energy consumption for large-scale operations, but further research is needed. PMID:16849131

Andreottola, Gianni; Foladori, Paola

2006-01-01

114

Emission of artificial sweeteners, select pharmaceuticals, and personal care products through sewage sludge from wastewater treatment plants in Korea.  

PubMed

Concern over the occurrence of artificial sweeteners (ASWs) as well as pharmaceuticals and personal care products (PPCPs) in the environment is growing, due to their high use and potential adverse effects on non-target organisms. The data for this study are drawn from a nationwide survey of ASWs in sewage sludge from 40 representative wastewater treatment plants (WWTPs) that receive domestic (WWTPD), industrial (WWTPI), or mixed (domestic plus industrial; WWTPM) wastewaters in Korea. Five ASWs (concentrations ranged from 7.08 to 5220ng/g dry weight [dw]) and ten PPCPs (4.95-6930ng/g dw) were determined in sludge. Aspartame (concentrations ranged from 28.4 to 5220ng/g dw) was determined for the first time in sewage sludge. The median concentrations of ASWs and PPCPs in sludge from domestic WWTPs were 0.8-2.5 and 1.0-3.4 times, respectively, the concentrations found in WWTPs that receive combined domestic and industrial wastewaters. Among the five ASWs analyzed, the median environmental emission rates of aspartame through domestic WWTPs (both sludge and effluent discharges combined) were calculated to be 417?g/capita/day, followed by sucralose (117?g/capita/day), acesulfame (90?g/capita/day), and saccharin (66?g/capita/day). The per-capita emission rates of select PPCPs, such as antimicrobials (triclocarban: 158?g/capita/day) and analgesics (acetaminophen: 59?g/capita/day), were an order of magnitude higher than those calculated for antimycotic (miconazole) and anthelmintic (thiabendazole) drugs analyzed in this study. Multiple linear regression analysis of measured concentrations of ASWs and PPCPs in sludge revealed that several WWTP parameters, such as treatment capacity, population-served, sludge production rate, and hydraulic retention time could influence the concentrations found in sludge. PMID:24695211

Subedi, Bikram; Lee, Sunggyu; Moon, Hyo-Bang; Kannan, Kurunthachalam

2014-07-01

115

Mercury mass balance at a wastewater treatment plant employing sludge incineration with offgas mercury control  

Microsoft Academic Search

Efforts to reduce the deliberate use of mercury (Hg) in modern industrialized societies have been largely successful, but the minimization and control of Hg in waste streams are of continuing importance. Municipal wastewater treatment plants are collection points for domestic, commercial, and industrial wastewaters, and Hg removal during wastewater treatment is essential for protecting receiving waters. Subsequent control of the

Steven J. Balogh; Yabing H. Nollet

2008-01-01

116

Influence of bioselector processes on 17?-ethinylestradiol biodegradation in activated sludge wastewater treatment systems.  

PubMed

The removal of the potent endocrine-disrupting estrogen hormone, 17?-ethinylestradiol (EE2), in municipal wastewater treatment plant (WWTP) activated sludge (AS) processes can occur through biodegradation by heterotrophic bacteria growing on other organic wastewater substrates. Different kinetic and metabolic substrate utilization conditions created with AS bioselector processes can affect the heterotrophic population composition in AS. The primary goal of this research was to determine if these changes also affect specific EE2 biodegradation kinetics. A series of experiments were conducted with parallel bench-scale AS reactors treating municipal wastewater with estrogens at 100-300 ng/L concentrations to evaluate the effect of bioselector designs on pseudo first-order EE2 biodegradation kinetics normalized to mixed liquor volatile suspended solids (VSS). Kinetic rate coefficient (kb) values for EE2 biodegradation ranged from 5.0 to 18.9 L/g VSS/d at temperatures of 18 °C to 24 °C. EE2 kb values for aerobic biomass growth at low initial food to mass ratio feeding conditions (F/Mf) were 1.4 to 2.2 times greater than that from growth at high initial F/Mf. Anoxic/aerobic and anaerobic/aerobic metabolic bioselector reactors achieving biological nutrient removal had similar EE2 kb values, which were lower than that in aerobic AS reactors with biomass growth at low initial F/Mf. These results provide evidence that population selection with growth at low organic substrate concentrations can lead to improved EE2 biodegradation kinetics in AS treatment. PMID:24810975

Ziels, Ryan M; Lust, Mariko J; Gough, Heidi L; Strand, Stuart E; Stensel, H David

2014-06-01

117

Application of the upflow anaerobic sludge bed (UASB) process for treatment of complex wastewaters at low temperatures  

SciTech Connect

The feasibility of the upflow anaerobic sludge bed (UASB) process for the treatment of potato starch wastewater at low ambient temperatures was demonstrated by operating two 5.65 l reactors at 14 degrees C and 20 degrees C, respectively. The organic space loading rates achieved in these laboratory-scale reactors were 3 kg COD/cubic m/day at 14 degrees C and 4-5 kg COD/cubic m/day at 20 degrees C. The corresponding sludge loading rates were 0.12 kg COD/kg VSS/day at 14 degrees C and 0.16-0.18 kg COD/kg VSS/day at 20 degrees C. These findings are of considerable practical importance because application of anaerobic treatment at low ambient temperatures will lead to considerable savings in energy needed for operating the process. As compared with various other anaerobic wastewater treatment processes, a granular sludge upflow process represents one of the best options developed so far. Although the overall sludge yield under psychrophilic conditions is slightly higher than under optimal mesophilic conditions, this doesn't seriously hamper the operation of the process. The extra sludge yield, due to accumulation of slowly hydrolyzing substrate ingredients, was 4.75% of the COD input at 14 degrees C and 1.22% of the COD input at 20 degrees C. 26 references.

Koster, I.W.; Lettinga, G.

1985-10-01

118

Identical full-scale biogas-lift reactors (Blrs) with anaerobic granular sludge and residual activated sludge for brewery wastewater treatment and kinetic modeling.  

PubMed

Two identical full-scale biogas-lift reactors treating brewery wastewater were inoculated with different types of sludge to compare their operational conditions, sludge characteristics, and kinetic models at a mesophilic temperature. One reactor (R1) started up with anaerobic granular sludge in 12 weeks and obtained a continuously average organic loading rate (OLR) of 7.4 kg chemical oxygen demand (COD)/(m3 x day), COD removal efficiency of 80%, and effluent COD of 450 mg/L. The other reactor (R2) started up with residual activated sludge in 30 weeks and granulation accomplished when the reactor reached an average OLR of 8.3 kg COD/(m3 x day), COD removal efficiency of 90%, and effluent COD of 240 mg/L. Differences in sludge characteristics, biogas compositions, and biogas-lift processes may be accounted for the superior efficiency of the treatment performance of R2 over R1. Grau second-order and modified StoverKincannon models based on influent and effluent concentrations as well as hydraulic retention time were successfully used to develop kinetic parameters of the experimental data with high correlation coefficients (R2 > 0.95), which further showed that R2 had higher treatment performance than R1. These results demonstrated that residual activated sludge could be used effectively instead of anaerobic granular sludge despite the need for a longer time. PMID:24494489

Xu, Fu; Huang, Zhenxing; Miao, Hengfeng; Ren, Hongyan; Zhao, Mingxing; Ruan, Wenquan

2013-10-01

119

Treatment of Coal Conversion Wastewater with the Powdered Activated Carbon-Contact Stabilization Activated Sludge Process. Third Semiannual Technical Progress Report, August 1, 1981-January 31, 1982.  

National Technical Information Service (NTIS)

The present research project evaluates the effectiveness of the powdered activated carbon-contact stabilization activated sludge process in the treatment of a coke oven wastewater. Nitrification and subsequent denitrification of the contact-stabilization ...

M. T. Suidan C. S. Gee M. A. Deady

1982-01-01

120

Treatment of chemical mechanical polishing wastewater by electrocoagulation: system performances and sludge settling characteristics  

Microsoft Academic Search

Treatment of copper chemical mechanical polishing (CMP) wastewater from a semiconductor plant by electrocoagulation is investigated. The CMP wastewater was characterized by high suspended solids (SS) content, high turbidity (NTU), chemical oxygen demand (COD) concentration up to 500 mgl?1 and copper concentration up to 100 mgl?1. In the present study, electrocoagulation was employed to treat the CMP wastewater with an

Chen L. Lai; Sheng H. Lin

2004-01-01

121

Savings with upgraded performance through improved activated sludge denitrification in the combined activated sludge-biofilter system of the Southpest Wastewater Treatment Plant.  

PubMed

The purpose of the experiments was to increase the rate of activated sludge denitrification in the combined biological treatment system of the Southpest Wastewater Treatment Plant in order to gain savings in cost and energy and improve process efficiency. Initial profile measurements revealed excess denitrification capacity of the preclarified wastewater. As a consequence, flow of nitrification filter effluent recirculated to the anoxic activated sludge basins was increased from 23,000 m3 d(-1) to 42,288 m3 d(-1) at an average preclarified influent flow of 64,843 m3 d(-1), Both simulation studies and microbiological investigations suggested that activated sludge nitrification, achieved despite the low SRT (2-3 days), was initiated by the backseeding from the nitrification filters and facilitated by the decreased oxygen demand of the influent organics used for denitrification. With the improved activated sludge denitrification, methanol demand could be decreased to about half of the initial value. With the increased efficiency of the activated sludge pre-denitrification, plant effluent COD levels decreased from 40-70 mg l(-1) to < 30-45 mg l(-1) due to the decreased likelihood of methanol overdosing in the denitrification filter. PMID:18469403

Jobbágy, A; Tardy, G M; Palkó, Gy; Benáková, A; Krhutková, O; Wanner, J

2008-01-01

122

Advanced sludge treatment affects extracellular polymeric substances to improve activated sludge dewatering  

Microsoft Academic Search

The management of wastewater sludge, now often referred to as biosolids, accounts for a major portion of the cost of the wastewater treatment process and represents significant technical challenges. In many wastewater treatment facilities, the bottleneck of the sludge handling system is the dewatering operation. Advanced sludge treatment (AST) processes have been developed in order to improve sludge dewatering and

Elisabeth Neyens; Jan Baeyens; Raf Dewil; Bart De heyder

2004-01-01

123

Limitation of sludge biotic index application for control of a wastewater treatment plant working with shock organic and ammonium loadings.  

PubMed

This study aimed to determine the relationship between activated sludge microfauna, the sludge biotic index (SBI) and the effluent quality of a full-scale municipal wastewater treatment plant (WWTP) working with shock organic and ammonium loadings caused by periodic wastewater delivery from septic tanks. Irrespective of high/low effluent quality in terms of COD, BOD5, ammonium and suspended solids, high SBI values (8-10), which correspond to the first quality class of sludge, were observed. High SBI values were connected with abundant taxonomic composition and the domination of crawling ciliates with shelled amoebae and attached ciliates. High SBI values, even at a low effluent quality, limit the usefulness of the index for monitoring the status of an activated sludge system and the effluent quality in municipal WWTP-treated wastewater from septic tanks. It was shown that a more sensitive indicator of effluent quality was a change in the abundance of attached ciliates with a narrow peristome (Vorticella infusionum and Opercularia coarctata), small flagellates and crawling ciliates (Acineria uncinata) feeding on flagellates. PMID:21802913

Drzewicki, Adam; Kulikowska, Dorota

2011-11-01

124

Sorption of Perfluorinated Compounds onto different types of sewage sludge and assessment of its importance during wastewater treatment.  

PubMed

The distribution coefficient (Kd) and the organic carbon distribution coefficient (KOC) were determined for four Perfluorinated Compounds (PFCs) to three different types of sludge taken from a conventional Sewage Treatment Plant (STP). Batch experiments were performed in six different environmental relevant concentrations (200ngL(-1)to 5?gL(-1)) containing 1gL(-1) sludge. Kd values ranged from 330 to 6015, 329 to 17432 and 162 to 11770Lkg(-1) for primary, secondary and digested sludge, respectively. The effects of solution's pH, ionic strength and cation types on PFCs sorption were also evaluated. Sorption capacities of PFCs significantly decreased with increased pH values from 6 to 8. Furthermore, the divalent cation (Ca(2+)) enhanced PFCs sorption to a higher degree in comparison with the monovalent cation (Na(+)) at the same ionic strength. The obtained Kd values were applied to estimate the sorbed fractions of each PFC in different stages of a typical STP and to calculate their removal through treated wastewater and sludge. In primary settling tank, the predicted sorbed fractions ranged from 3% for Perfluorooctanoic Acid (PFOA) to 55% for Perfluoroundecanoic acid (PFUdA), while in activated sludge tank and anaerobic digester sorption was more than 50% for all target compounds. Almost 86% of initial PFOA load is expected to be detected in treated wastewater; while Perfluorodecanoic acid (PFDA), PFUdA and Perfluorooctanesulfonate (PFOS) can be significantly removed (>49%) via sorption to primary and excess secondary sludge. In anaerobic digester, the major part (>76%) of target PFCs is expected to be sorbed to sludge, while almost 3% of initial PFOA load will be detected in sludge leachates. PMID:24997945

Arvaniti, Olga S; Andersen, Henrik R; Thomaidis, Nikolaos S; Stasinakis, Athanasios S

2014-09-01

125

Application of the upflow anaerobic sludge bed (UASB) process for treatment of complex wastewaters at low temperatures  

Microsoft Academic Search

The feasibility of the upflow anaerobic sludge bed (UASB) process for the treatment of potato starch wastewater at low ambient temperatures was demonstrated by operating two 5.65 l reactors at 14 degrees C and 20 degrees C, respectively. The organic space loading rates achieved in these laboratory-scale reactors were 3 kg COD\\/cubic m\\/day at 14 degrees C and 4-5 kg

I. W. Koster; G. Lettinga

1985-01-01

126

Combined activated sludge with partial nitrification (AS\\/PN) and anammox processes for treatment of seafood processing wastewater  

Microsoft Academic Search

An activated sludge process with partial nitrification (AS\\/PN) in combination with anaerobic ammonium oxidation (Anammox) process for treatment of seafood processing wastewater was developed and investigated in this research. Operating conditions of AS\\/PN process for coupling with Anammox process were identified as pH between 7.7–8.2 and DO as 0.5–0.9 mg L to achieve over 85% COD removal as well as

Apipong Lamsam; Sawanya Laohaprapanon; Ajit P. Annachhatre

2008-01-01

127

Feasibility of expanded granular sludge bed reactors for the anaerobic treatment of low-strength soluble wastewaters  

Microsoft Academic Search

The application of the expanded granular sludge bed (EGSB) reactor for the anaerobic treatment of low-strength soluble wastewaters using ethanol as a model substrate was investigated in laboratory-scale reactors at 30 C. Chemical oxygen demand (COD) removal efficiency was above 80% at organic loading rates up to 12 g COD\\/L [center dot] d with influent concentrations as low as 100

Mario T. Kato; Jim A. Field; Paul Versteeg; Gatze Lettinga

1994-01-01

128

Empirical Model for Predicting Concentrations of Refractory Hydrophobic Organic Compounds in Digested Sludge from Municipal Wastewater Treatment Plants  

PubMed Central

An empirical model is presented allowing for the prediction of concentrations of hydrophobic organic compounds (HOCs) prone to accumulate and persist in digested sludge (biosolids) generated during conventional municipal wastewater treatment. The sole input requirements of the model are the concentrations of the individual HOCs entering the wastewater treatment plant in raw sewage, the compound’s respective pH-dependent octanol-water partitioning coefficient (DOW), and an empirically determined fitting parameter (pfit) that reflects persistence of compounds in biosolids after accounting for all potential removal mechanisms during wastewater treatment. The accuracy of the model was successfully confirmed at the 99% confidence level in a paired t test that compared predicted concentrations in biosolids to empirical measurements reported in the literature. After successful validation, the resultant model was applied to predict levels of various HOCs for which occurrence data in biosolids thus far are lacking.

Deo, Randhir P.; Halden, Rolf U.

2009-01-01

129

Dynamics of the microfauna community in a full-scale municipal wastewater treatment plant experiencing sludge bulking.  

PubMed

We investigated the dynamics of the microfauna community in activated sludge, with special reference to sludge bulking, in two parallel municipal wastewater treatment systems in Beijing, China over a period of 14 months. Annual cyclic changes in microfauna community structures occurred in both systems. RELATE analysis based on Spearman's Rank correlation indicated that microfauna community structures were highly correlated with the sludge volume index (SVI) (p<0.001), which indicates sludge settleability. Nutrient conditions of raw sewage (p<0.01) and hydraulic retention time (HRT) (p<0.05) were also related to microfauna community structures. Abundances of the species Epistylis plicatilis and Vorticella striata increased significantly with an increase in SVI (p<0.001) and decrease in water temperature (p<0.001), suggesting that sludge bulking may have created favorable conditions for the two species, even under unfavorable temperature conditions. Sludge de-flocculation primarily due to the excessive growth of Microthrix parvicella-like filaments could be an important driving force for the microfauna community changes. The release of flocculated non-filamentous bacteria may represent a suitable food source for these species. The two species may be considered as potential bioindicators for sludge bulking. PMID:23628141

Hu, Bo; Qi, Rong; An, Wei; Xu, Muqi; Zhang, Yu; Bai, Xue; Bao, Haipeng; Wen, Yang; Gu, Jian; Yang, Min

2013-11-01

130

Feasibility of expanded granular sludge bed reactors for the anaerobic treatment of low-strength soluble wastewaters  

SciTech Connect

The application of the expanded granular sludge bed (EGSB) reactor for the anaerobic treatment of low-strength soluble wastewaters using ethanol as a model substrate was investigated in laboratory-scale reactors at 30 C. Chemical oxygen demand (COD) removal efficiency was above 80% at organic loading rates up to 12 g COD/L [center dot] d with influent concentrations as low as 100 to 200 mg COD/L. These results demonstrate the suitability of the EGSB reactor for the anaerobic treatment of low-strength wastewaters. The high treatment performance can be attributed to the intense mixing regime obtained by high hydraulic and organic loads. Good mixing of the bulk liquid phase for the substrate-biomass contact and adequate expansion of the sludge bed for the degassing were obtained when the liquid upflow velocity (V[sub up]) was greater than 2.5 m/h. Under such conditions, an extremely low apparent K[sub s] value for acetoclastic methanogenesis of 9.8 mg COD/L was observed. The presence of dissolved oxygen in the wastewater had no detrimental effect on the treatment performance. Sludge piston flotation from pockets of biogas accumulating under the sludge bed occurred at V[sub up] lower than 2.5 m/h due to poor bed expansion. This problem is expected only in small diameter laboratory-scale reactors. A more important restriction of the EGSB reactor was the sludge washout occurring at V[sub up] higher than 5.5 m/h and which was intensified at organic loads higher than 7 g COD/L [center dot] d due to buoyancy forces from the gas production.

Kato, M.T.; Field, J.A.; Versteeg, P.; Lettinga, G. (Wageningen Agricultural Univ. (Netherlands). Dept. of Environmental Technology)

1994-08-05

131

Thermal hydrolysis of waste activated sludge at Hengelo Wastewater Treatment Plant, The Netherlands.  

PubMed

The thermal hydrolysis process (THP) is a sludge treatment technique which affects anaerobic biodegradability, viscosity and dewaterability of waste activated sludge (WAS). In 2011 a THP-pilot plant was operated, connected to laboratory-scale digesters, at the water board Regge en Dinkel and in cooperation with Cambi A.S. and MWH Global. Thermal hydrolysis of WAS resulted in a 62% greater volatile solids (VS) reduction compared to non-hydrolysed sludge. Furthermore, the pilot digesters could be operated at a 2.3 times higher solids loading rate compared to conventional sludge digesters. By application of thermal sludge hydrolysis, the overall efficiency of the sludge treatment process can be improved. PMID:25026572

Oosterhuis, Mathijs; Ringoot, Davy; Hendriks, Alexander; Roeleveld, Paul

2014-01-01

132

Wastewater Treatment  

NSDL National Science Digital Library

This lesson introduces students to the basics of wastewater treatment. Topics include the variety of materials that enter the wastewater system, septic tanks, and municpal treatment systems. Students can review online resources that describe the processes of wastewater treatment and septic tank operation in detail, and listen to a National Publc Radio (NPR) show that discusses the use of treated wastewater to make snow at a ski resort in Maine. The lesson includes an activity in which students participate in virtual tours of wastewater treatment facilities and answer questions about what they see.

Laposata, Mark

133

Modeling the performance of “up-flow anaerobic sludge blanket” reactor based wastewater treatment plant using linear and nonlinear approaches—A case study  

Microsoft Academic Search

The paper describes linear and nonlinear modeling of the wastewater data for the performance evaluation of an up-flow anaerobic sludge blanket (UASB) reactor based wastewater treatment plant (WWTP). Partial least squares regression (PLSR), multivariate polynomial regression (MPR) and artificial neural networks (ANNs) modeling methods were applied to predict the levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD)

Kunwar P. Singh; Nikita Basant; Amrita Malik; Gunja Jain

2010-01-01

134

A Guide for Developing Standard Operating Job Procedures for the Activated Sludge - Aeration & Sedimentation Process Wastewater Treatment Facility. SOJP No. 5.  

ERIC Educational Resources Information Center

This guide for developing standard operating job procedures for wastewater treatment facilities is devoted to the activated sludge aeration and sedimentation process. This process is for conversion of nonsettleable and nonfloatable materials in wastewater to settleable, floculated biological groups and separation of the settleable solids from the…

Mason, George J.

135

Integrated nanofiltration and upflow anaerobic sludge blanket treatment of textile wastewater for in-plant reuse.  

PubMed

The filtration characteristics of simulated dyeing effluents containing Acid Orange 7, sodium sulfate, and a pH buffer made of acetic acid and sodium acetate is described using a commercially available nanofiltration membrane. The original membrane filtration properties were characterized with deionized water to provide a baseline of membrane performance. At high volumetric concentration of the test solutions, greater than 98% rejection of dye and sodium sulfate were obtained. Rejection of buffering chemicals was approximately 50% in all experiments, giving a permeate water not suitable for reuse in most dyeing operations. The final composite concentrate had a chemical oxygen demand (COD) value > 2000 mg/L. No problems were encountered with anaerobic treatment of the concentrate obtained from the dyeing wastewater. Adjusting the sulfate concentration to give COD-to-sulfate ratios to 2.9, 5.4, and 18.2 in the reactor feed had no significant alterations in the performance of the upflow anaerobic sludge blanket reactor. PMID:17571839

Gomes, Arlindo Canigo; Gonçalves, Isolina Cabral; de Pinho, Maria Norberta; Porter, John Jefferson

2007-05-01

136

Stabilization of heavy metals in wastewater treatment sludge from power plants air heater washing.  

PubMed

In the present investigation, for the first time in Iran, dewatered sludge waste from the air heater washing wastewater treatment of a thermal power plant was subject to investigation with regard to cement-based stabilization in order to reduce the mobility of heavy metals. Studies of the chemical composition, mineralogy, morphology and leaching characteristics of the untreated and treated waste were conducted. The stabilization was done with two cement-based mix designs with different waste/cement ratios in different samples. In the cement stabilization process the leaching of V, Ni, Zn and Cr could be decreased from 314.1, 209.1, 24.8 and 5.5 mg L(-1), respectively, in the untreated waste to 6.02, 32.11, 3.57 and 3.68 mg L(-1) in a mixture with 20% waste/cement ratio, while during stabilization with cement + sand, the toxicity characteristic leaching procedure (TCLP) leachate contents of the mentioned metals were decreased to 4.24, 16.2, 2.51 and 2.2 mg L(-1) for the same waste/cement ratio. Stabilization with sand/cement seemed to be more efficient in reducing metal leaching from the waste. X-ray diffraction studies showed that portlandite, calcite, lime, larnite and quartz were produced during the stabilization process. PMID:19423607

Saeedi, Mohsen; Amini, Hamid Reza

2009-05-01

137

Occurrence of PBDEs and other alternative brominated flame retardants in sludge from wastewater treatment plants in Korea.  

PubMed

Studies on the occurrence of polybrominated diphenyl ethers (PBDEs) and other alternative brominated flame retardants in the environment are scarce. In this study, PBDEs and non-PBDE brominated flame retardants (NBFRs), including decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), were measured in sludge collected from three types of wastewater treatment plants (WWTPs) in Korea. Total concentrations of PBDEs (?PBDE) in sludge ranged from 298 to 48,000 (mean: 3240) ng/g dry weight. Among 10 NBFRs analyzed, DBDPE and BTBPE were the only ones detected in sludge samples. Concentrations of DBDPE and BTBPE ranged from sludge were higher than those reported in other countries. The highest concentrations of ?PBDE and DBDPE were found in sludge samples originated from industrial-WWTPs (I-WWTPs), suggesting that industrial activities are a major source of these contaminants. Non-parametric multidimensional scaling ordination showed that congener profiles of PBDEs in sludge are dependent on the types of WWTPs. Almost all sludge samples contained a low ratio (mean: 0.18) of DBDPE/BDE 209, indicating an on-going contamination by PBDEs in Korea. However, the high ratios (>1) of DBDPE/BDE 209 were found in sludge from I-WWTPs, reflecting a shift in the usage pattern of BFRs by the Korean industry. The nationwide annual emission fluxes of ?PBDE, DBDPE and BTBPE via WWTPs to the environment were estimated to be 7400, 480, and 3.7 kg/year, respectively. This is the first study on the occurrence of alternative brominated flame retardants in sludge from Korea. PMID:23993837

Lee, Sunggyu; Song, Geum-Ju; Kannan, Kurunthachalam; Moon, Hyo-Bang

2014-02-01

138

DESIGN MANUAL: DEWATERING MUNICIPAL WASTEWATER SLUDGES  

EPA Science Inventory

This manual discusses the many factors involved in selecting and designing dewatering equipment for organic sludges produced during primary and secondary municipal wastewater treatment. ive-step approach is outlined for the selection and design of the dewatering equipment for eit...

139

A comparative study of freeze-thaw processes for conditioning wastewater and water treatment sludges  

SciTech Connect

This research effort involved the application of indirect- and direct-contact, freeze-thaw conditioning techniques for improving the dewatering characteristics of both waste water and water treatment sludges. Sludges tested included waste activated sludge, primary sewage sludge, waste activated/primary sewage sludge mixtures and alum sludge. The direct-freeze methods examined were the use of a secondary refrigerant (butane) evaporated in the sludge and the use of gas hydrate or clathrate formation by addition of Freon 12 under appropriate temperature and pressure conditions. Sludges were also frozen solid using indirect freezing methods, thawed and tested for comparative purposes. Particle size distribution and floc density measurements were used to determine changes in particle characteristics; specific resistance values and dewatered dry solids concentration were used to assess dewatering characteristics. Results of direct and indirect-contact, freeze-thaw conditioning were compared to the effects of polymer conditioning. The results indicated that direct-freeze methods do not appear technically or economically competitive with currently accepted conditioning methods. The superior results obtained with the indirect-contact, freeze-thaw process when compared to the direct-contact processes suggested that the extent and rate of freezing may greatly influence the particle characteristics of the conditioned sludge, and thus its dewatering characteristics.

Trahern, P.G.

1989-01-01

140

Nitrogen Removal in a Full-Scale Domestic Wastewater Treatment Plant with Activated Sludge and Trickling Filter  

PubMed Central

During the last decade, more stringent effluent requirements concerning the nutrients effluent values have been imposed by legislation and social concern. In this study, efficiency of total nitrogen removal in activated sludge and trickling filter processes (AS/TF) was investigated in Tehran North wastewater treatment plant. Biological system in this site was included, anoxic selector tank, aeration tank, final sedimentation, and trickling filter. A part of treated wastewater before chlorination was mixed with supernatant of dewatered sludge and fed to the trickling filter. Supernatant of dewatered sludge with high concentration of NH4-N was diluted by treated wastewater to provide complete nitrification in trickling filter Produced nitrate in trickling filter was arrived to the anoxic tank and converted to nitrogen gas by denitrification. According to the study result, low concentration of organic carbone and high concentration of NH4-N led to nitrification in TF, then nitrate denitrification to nitrogen gas occurred in selector area. NH4-N concentration decreased from 26.8?mg/L to 0.29?mg/L in TF, and NO3-N concentration increased from 8.8?mg/L to 27?mg/L in TF. Consequently, the total nitrogen decreased approximately to 50% in biological process. This efficiency has been observed in returned flow around 24% from final sedimentation into TF. It was concluded that, in comparison with biological nutrient removal processes, this process is very efficient and simple.

Nourmohammadi, Davood; Esmaeeli, Mir-Bager; Akbarian, Hossein; Ghasemian, Mohammad

2013-01-01

141

Evaluation of sludge reduction and carbon source recovery from excess sludge by the advanced Sludge reduction, Inorganic solids separation, Phosphorus recovery, and Enhanced nutrient Removal (SIPER) wastewater treatment process.  

PubMed

An advanced wastewater treatment process involving Sludge reduction, Inorganic solids separation, Phosphorus recovery, and Enhanced nutrient Removal (SIPER) was developed to reduce sludge production, prevent the accumulation of inorganic solids, recover phosphorus, and enhance nutrient removal. The feasibility of recovering carbon (C)-source from excess sludge to enhance nutrient removal and the sludge reduction potential of the process was evaluated. The results showed that sludge hydrolysis and acidification yields were 20±3% and 34±2%, respectively. The COD/TN and VFA/TP ratios for the supernatant of alkaline-treated sludge were 2.8 and 2.5 times those in the influent, respectively. Nutrients were removed effectively in the system, especially TN, for which the removal efficiency reached 80±2%. The C-source recovered from the excess sludge was successfully employed as an internal C-source for enhanced nutrient removal. The observed sludge yield of the system was 0.096 g VSS g COD(-1), demonstrating the excellent sludge reduction potential of this process. PMID:24185418

Yan, Peng; Ji, Fangying; Wang, Jing; Fan, Jianping; Guan, Wei; Chen, Qingkong

2013-12-01

142

Solidification/Stabilization of Sludge and Ash from Wastewater Treatment Plants.  

National Technical Information Service (NTIS)

Tests were performed to determine the physical properties and chemical leaching characteristics of the residuals and the stabilized/solidified products from two publicly-owned wastewater treatment works (POTW). The two POTW waste products included in this...

P. G. Malone L. W. Jones

1985-01-01

143

Stoichiometric and molecular evidence for the enrichment of anaerobic ammonium oxidizing bacteria from wastewater treatment plant sludge samples.  

PubMed

Anammox enrichments were readily developed from seven municipal wastewater treatment plants (WWTPs) sludge, but not with methanogenic granular sludge from two agro-industrial WWTPs. Only 50d was required for the first evidence of anammox activity from a return activated sludge obtained from a WWTP operated for nutrient removal. The molar ratios of nitrite and ammonium consumption of approximately 1.32 as well as nitrate and dinitrogen gas product ratios of approximately 0.095 provided evidence of the anammox reaction. The presence of anammox was confirmed by polymerase chain reaction (PCR) using primer sets (PLA46F and AMX820R) specific for anammox bacteria. The 16S rRNA gene fragment of anammox bacteria was detected in seven enrichment cultures (ECs) with demonstrated anammox activity but not in the original inocula from which the ECs were derived and also not in the two methanogenic sludge samples, which indicates the PCR predicted the anammox activity. Two genera, Brocadia and Kuenenia, were successfully identified as the Planctomycetes occurring in the clone libraries of successful anammox enrichments. Brocadia dominated in cultures that were respiked extensively; whereas Kuenenia predominated in cultures that were less aggressively respiked. These findings indicate that respiking management may play an important role on selecting the genus of anammox bacteria. The batch enrichment results clearly illustrate that anammox can be readily enriched from municipal sludge from a wide variety of process operations at WWTPs. PMID:21620436

Sun, Wenjie; Banihani, Qais; Sierra-Alvarez, Reyes; Field, Jim A

2011-08-01

144

Determination of azoles in sewage sludge from Spanish wastewater treatment plants by liquid chromatography-tandem mass spectrometry.  

PubMed

A simple and rapid analytical method for the determination of 16 azoles in sewage sludge has been developed and validated. The method was based on ultrasound-assisted extraction followed by dispersive solid-phase extraction cleanup and liquid chromatography-electrospray tandem mass spectrometric detection. The azoles were selected by their intensive usage as biocides (tebuconazole, propiconazole, cyproconazole and thiabendazole), antimycotic pharmaceuticals (ketoconazole, econazole, fluconazole and clotrimazole) or fungicides in agriculture (difenoconazole, flusilazole, hexaconazole, prochloraz, bromuconazole, epoxiconazole and triticonazole). The recoveries of these compounds through the method were between 71.9 and 115.8%, with relative standard deviations lower than 20%. Detection limits were in the range of 0.5-5.0 ng/g. The developed method was applied to the analysis of azoles in sewage sludge samples collected from 19 Spanish wastewater treatment plants. Although azoles used as biocides or agriculture fungicides were present in a few sludge samples, the pharmaceuticals ketoconazole, econazole and clotrimazole were present in all of the analyzed sludge samples, being ketoconazole the one found at the highest level, representing the 68.6% of the total azole content found in the 19 sludge samples studied. PMID:21491590

García-Valcárcel, Ana I; Tadeo, José L

2011-06-01

145

Investigation of extracellular polymer substances (EPS) and physicochemical properties of activated sludge from different municipal and industrial wastewater treatment plants.  

PubMed

This paper examines the chemical constituents of extracellular polymeric substances (EPS) and physicochemical properties of eight different sludge flocs from seven full-scale wastewater treatment plants. The physicochemical properties included floc properties (floc size, turbidity and effluent suspended solids (ESS) content of the supernatant), sludge volume index, capillary suction time and specific resistance to filtration. The relationships between the chemical constituents of EPS and the flocculation, settleability and dewaterability of sludge flocs were also assessed. The results showed that higher amounts of EPS were found in the municipal sludge flocs than in the industrial sludges. The content of tightly bound EPS (TB-EPS) was much greater than that of loosely bound EPS (LB-EPS). The amounts of total EPS, LB-EPS, TB-EPS and protein in LB-EPS were strongly related to ESS. The ratios of total protein to EPS and total carbohydrate to EPS showed positive correlation to the flocs size. It was surprising that there was no correlation between settleability or dewaterability and the chemical constituents of EPS. PMID:22720410

Peng, Ge; Ye, Fenxia; Li, Ying

2012-01-01

146

PAH removal from spiked municipal wastewater sewage sludge using biological, chemical and electrochemical treatments.  

PubMed

Polycyclic aromatic hydrocarbons (PAHs) have been widely studied due to their presence in all the environmental media and toxicity to life. These molecules are strongly adsorbed on the particulate matters of soils, sludges or sediments because of their strong hydrophobicity which makes them less bioavailability, thus limiting their bioremediation. Different sludge treatment processes were tested to evaluate their performances for PAH removal from sludge prealably doped with 11 PAHs (5.5mg each PAH kg(-1) of dry matter (DM)): two biological processes (mesophilic aerobic digestion (MAD) and simultaneous sewage sludge digestion and metal leaching (METIX-BS)) were tested to evaluate PAH biodegradation in sewage sludge. In parallel, two chemical processes (quite similar Fenton processes: chemical metal leaching (METIX-AC) and chemical stabilization (STABIOX)) and one electrochemical process (electrochemical stabilization (ELECSTAB)) were tested to measure PAH removal by these oxidative processes. Moreover, PAH solubilisation from sludge by addition of a nonionic surfactant Tween 80 (Tw80) was also tested. The best yields of PAH removal were obtained by MAD and METIX-BS with more than 95% 3-ring PAH removal after a 21-day treatment period. Tw80 addition during MAD treatment increased 4-ring PAHs removal rate. In addition, more than 45% of 3-ring PAHs were removed from sludge by METIX-AC and during ELECSTAB process were quiet good with approximately 62% of 3-ring PAHs removal. However, little weaker removal of 3-ring PAHs (<35%) by STABIOX. None of the tested processes were efficient for the elimination of high molecular weight (> or = 5-ring) PAHs from sludge. PMID:17337031

Zheng, Xue-Jing; Blais, Jean-François; Mercier, Guy; Bergeron, Mario; Drogui, Patrick

2007-06-01

147

Distributions of polycyclic musk fragrance in wastewater treatment plant (WWTP) effluents and sludges in the United States.  

PubMed

The polycyclic musks, AHTN and HHCB are fragrance ingredients widely used in consumer products. A monitoring campaign was conducted and collected grab effluent and sludge samples at 40 wastewater treatment plants (WWTP) across the United States to understand their occurrence and statistical distribution in these matrices. AHTN concentration in effluent ranged from <0.05?g/L (LOQ) to 0.44?g/L with a mean and standard deviation of 0.18±0.11?g/L. HHCB concentrations in effluent ranged from 0.45 to 4.79?g/L with a mean of 1.86±1.01?g/L. AHTN concentrations in sludge ranged from 0.65 to 15.0mg/kg dw (dry weight) with a mean and standard deviation being 3.69±2.57mg/kg dw, while HHCB sludge concentrations were between 4.1 and 91mg/kg with a mean of 34.0±23.1mg/kg dw. Measured concentrations of AHTN and HHCB were significantly correlated with each other in both effluent and sludge. The concentrations of HHCB in both effluent and sludge were approximately an order of magnitude higher than those for AHTN, consistent with 2011 usage levels. The highest measured effluent concentrations for both AHTN and HHCB were below their respective freshwater PNECs (predicted no effect concentrations), indicating a negligible risk to biological communities below WWTPs, even in the absence of upstream dilution. Moreover, the large number of effluents and sludges sampled provides a statistical distribution of loadings that can be used to develop more extensive probabilistic exposure assessments for WWTP mixing zones and sludge amended soils. PMID:24792690

Sun, Ping; Casteel, Kenneth; Dai, Hongjian; Wehmeyer, Kenneth R; Kiel, Brian; Federle, Thomas

2014-09-15

148

Carbonate addition--an effective remedy against poor activated sludge settling properties and alkalinity conditions in small wastewater treatment plants.  

PubMed

The impact of marble powder on the performance of small seasonal treatment plants dealing with high ammonia concentrated wastewater has been investigated. The carbonate has been added to one of two parallel lab-scale SBR-systems as an alkalinity depot and a bio-carrier. The focus of the monitoring program was put on the measurement of carbon fractions in the liquid and the solid phase and on the alkalinity conditions. Monitoring results show a significant correlation between carbonate dosage (and corresponding inorganic carbon concentration and pH-value) and sludge volume index and nitrification rate. PMID:14753563

Wett, B; Eladawy, A; Becker, W

2003-01-01

149

Evaluation of operation of submerged aerated filters in wastewater treatment and excess sludge production.  

PubMed

The aims of this study were to evaluate the SCOD removal efficiency in submerged biological aerated filters (BAFs) and subsequently to assess the relationship between the specific surface area (Ss) and Excess Sludge Production (ESP) rate in such filters. Accordingly, four filters with different porosity and specific surface (647, 295, 175 and 136 m2 m(-3)) have been loaded with synthetic wastewater based on low fat dry milk powder with COD of 1500 mg L(-1) in different hydraulic retention time (8, 4, 2, 1 and 0.5 h). In this study, it was shown that specific surface increase of the filters initially increases the efficiency of the filters and after a certain value, the filter efficiency remains uncharged or decreases, as in HRT of 8 h the SCOD removal efficiency of filters 1 and 2 (Ss = 647 m2 m(-3) and Ss = 295 m2 m(-3)) were 89.8 and 91% at VOL of 3.195 and 3.727 kg COD m(-3) d(-1), respectively. Also, the results showed that in all the filters, the production rate of suspended sludge increases inversely with the hydraulic retention time and the media with higher porosity (90.5%) produced less suspended sludge (8-57 g m(-3)) despite having lower efficiency in the SCOD removal. PMID:19090097

Baghapour, Mohammad A; Jabbari, Ebrahim

2007-09-15

150

CROPPING SYSTEMS FOR TREATMENT AND UTILIZATION OF MUNICIPAL WASTEWATER AND SLUDGE  

EPA Science Inventory

The efficiency of nitrogen stripping by intercropping forages with corn is evaluated in a three-year study at Muskegon County Wastewater Treatment Facility in Michign. Corn is grown as the major cash crop at the Muskegon treatment facility, but experience has shown that corn is n...

151

DEVELOPMENT OF METHODS AND TECHNIQUES FOR FINAL TREATMENT OF COMBINED MUNICIPAL AND TEXTILE WASTEWATER INCLUDING SLUDGE UTILIZATION AND DISPOSAL  

EPA Science Inventory

The investigations were carried out on laboratory scale, employing various mixtures of dyeing and municipal wastewaters. The processes studied were: coagulation, ozonization, chlorination, activated carbon, activated sludge, and anaerobic digestion. Lime appeared to be the best c...

152

Sludge cycling between aerobic, anoxic and anaerobic regimes to reduce sludge production during wastewater treatment: performance, mechanisms, and implications.  

PubMed

Alternate cycling of sludge in aerobic, anoxic, and anaerobic regimes is a promising strategy that can reduce the sludge yield of conventional activated sludge (CAS) by up to 50% with potentially lower capital and operating cost than physical- and/or chemical-based sludge minimisation techniques. The mechanisms responsible for reducing sludge yield include alterations to cellular metabolism and feeding behaviour (metabolic uncoupling, feasting/fasting, and endogenous decay), biological floc destruction, and predation on bacteria by higher organisms. Though discrepancies across various studies are recognisable, it is apparent that sludge retention time, oxygen-reduction potential of the anaerobic tank, temperature, sludge return ratio and loading mode are relevant to sludge minimisation by sludge cycling approaches. The impact of sludge minimisation on CAS operation (e.g., organics and nutrient removal efficiency and sludge settleability) is highlighted, and key areas requiring further research are also identified. PMID:24529987

Semblante, Galilee U; Hai, Faisal I; Ngo, Huu H; Guo, Wenshan; You, Sheng-Jie; Price, William E; Nghiem, Long D

2014-03-01

153

Mechanisms of Decreased Digestibility in Chemically-Coagulated Wastewater Sludges.  

National Technical Information Service (NTIS)

Previous studies have indicated that coagulants used in wastewater treatment (principally alum or ferric chloride) caused resulting sludges to be less biodegradable in subsequent anaerobic digestion. The objectives of this research were: to determine the ...

J. M. Gossett S. K. Dentel J. J. Schruben

1979-01-01

154

IDENTIFICATION OF MUTAGENIC COMPONENTS IN WASTEWATER EFFLUENTS AND SLUDGES  

EPA Science Inventory

Both industrially-impacted and domestic municipal sewage treatment plant wastewaters and sludges have been studied to isolate the residue organics for the characterization of their mutagenic properties and for the isolation/identification of the mutagenic components. ethods were ...

155

POLISH/U.S. SYMPOSIUM ON WASTEWATER TREATMENT AND SLUDGE DISPOSAL HELD AT CINCINNATI, OHIO ON FEBRUARY 10-12, 1976. VOLUME II  

EPA Science Inventory

The publication comprises the proceedings of the Polish/U.S. Symposium on Wastewater Treatment and Sludge Disposal, held in Cincinnati, Ohio, February 10 through 12, 1976. Topics included both research work, notably in biodegradability and toxicity, and treatment and disposal met...

156

Wastewater Treatment.  

ERIC Educational Resources Information Center

Presents the 1978 literature review of wastewater treatment. This review covers: (1) process application; (2) coagulation and solids separation; (3) adsorption; (4) ion exchange; (5) membrane processes; and (6) oxidation processes. A list of 123 references is also presented. (HM)

Zoltek, J., Jr.; Melear, E. L.

1978-01-01

157

Transformation of four silver/silver chloride nanoparticles during anaerobic treatment of wastewater and post-processing of sewage sludge.  

PubMed

The increasing use of silver (Ag) nanoparticles [containing either elemental Ag (Ag-NPs) or AgCl (AgCl-NPs)] in commercial products such as textiles will most likely result in these materials reaching wastewater treatment plants. Previous studies indicate that a conversion of Ag-NPs to Ag2S is to be expected during wastewater transport/treatment. However, the influence of surface functionality, the nature of the core structure and the effect of post-processing on Ag speciation in sewage sludge/biosolids has not been investigated. This study aims at closing these knowledge gaps using bench scale anaerobic digesters spiked with Ag nitrate, three different types of Ag-NPs, and AgCl-NPs at environmentally realistic concentrations. The results indicate that neither surface functionality nor the different compositions of the NP prevented the formation of Ag2S. Silver sulfides, unlike the sulfides of other metals present in sewage sludge, were stable over a six month period simulating composting/stockpiling. PMID:23434771

Lombi, Enzo; Donner, Erica; Taheri, Shima; Tavakkoli, Ehsan; Jämting, Åsa K; McClure, Stuart; Naidu, Ravi; Miller, Bradley W; Scheckel, Kirk G; Vasilev, Krasimir

2013-05-01

158

SOLIDIFICATION/STABILIZATION OF SLUDGE AND ASH FROM WASTEWATER TREATMENT PLANTS  

EPA Science Inventory

Tests were performed to determine the physical properties and chemical leaching characteristics of the residuals and the stabilized/solidified products from two publicly-owned wastewater treatment works (POTW). The two POTW waste products included in this study were an anaerobic ...

159

Microfiltration of activated sludge using submerged membrane with air bubbling (application to wastewater treatment)  

Microsoft Academic Search

A membrane bioreactor is one of the applications of membrane technology to wastewater treatment. In this study we present the results obtained using hollow fiber microfiltration membranes directly immersed in the bioreactor. Two sizes of equipment were used: laboratory scale with a specially designed set of microfiltration hollow fibers (filtration area 0.016 m2) and pilot scale with a bundle of

El Hani Bouhabila; Roger Ben Aïm; Herve Buisson

1998-01-01

160

Emergy analysis of municipal wastewater treatment and generation of electricity by digestion of sewage sludge  

Microsoft Academic Search

This study examines and evaluates, by using emergy analysis, the use of environmental resources for wastewater treatment in a Swedish town. Emergy analysis was applied, while it facilitates the comparison of resource use of substantially different kind. In the emergy analysis, all resources are assessed on the basis of the amount of direct and indirect solar energy required in their

Johanna Björklund; Ulrika Geber; Torbjörn Rydberg

2001-01-01

161

Dissolved oxygen control of the activated sludge wastewater treatment process using stable adaptive fuzzy control  

Microsoft Academic Search

In the operation of wastewater treatment plants a key variable is dissolved oxygen (DO) content in the bioreactors. The paper describes the development of an adaptive fuzzy control strategy for tracking the DO reference trajectory applied to the Benchmark Simulation Model n.1. The design methodology of this data-driven controller uses the Lyapunov synthesis approach with a parameter projection algorithm to

Carlos Alberto Coelho Belchior; Rui Alexandre Matos Araújo; Jorge Afonso Cardoso Landeck

162

Activated sludge wastewater treatment plant modelling and simulation: state of the art  

Microsoft Academic Search

This review paper focuses on modelling of wastewater treatment plants (WWTP). White-box modelling is widely applied in this field, with learning, design and process optimisation as the main applications. The introduction of the ASM model family by the IWA task group was of great importance, providing researchers and practitioners with a standardised set of basis models. This paper introduces the

Krist V. Gernaey; Mark C. M. Van Loosdrecht; Mogens Henze; Morten Lind; Sten B. Jørgensen

2004-01-01

163

Microbiological basis of phosphate removal in the activated sludge process for the treatment of wastewater  

Microsoft Academic Search

Several strains resembling members of theAcinetobacter-Moraxella-Mima group of bacteria were isolated from activated sludge-type sewage treatment plants designed for phosphate removal. The bacteria are obligate aerobes but utilize as carbon and energy sources low-molecular intermediates generated anaerobically, particularly acetate and ethanol. These bacteria can be shown to be responsible for the phosphate luxury uptake occurring in these treatment plants. The

G. W. Fuhs; Min Chen

1975-01-01

164

Improved alkaline stabilization of municipal wastewater sludge.  

PubMed

In Mexico, physicochemical sludge contains high levels of pathogens; and alkaline stabilization is an alternative for their control. However, the odours caused mainly by ammonia generation represent a disadvantage. On the other hand, the ammonia is known as an effective disinfectant. The aim of this study was to evaluate the disinfectant properties of ammonia in sludge, and use it in a closed alkaline stabilization system, which, not only copes with odours but also increases the efficiency of the process. Raw sludge from a municipal wastewater treatment plant using a physicochemical process was used. Ammonia was applied in doses from 10 to 50% w/w; also, doses from 5 to 40% of CaO were applied in open and closed systems and raw and treated sludge quality was evaluated. Results showed that ammonia removed 6 and 5 logs of faecal coliforms and Salmonella spp., respectively and up to 94% of viable helminth ova. The closed system was more efficient than the open system when applying doses from 5 to 20% of CaO. Finally, the results indicate that the ammonia represents an alternative to disinfecting wastewater sludge and it can be used to enhance alkaline stabilization processes. PMID:12479463

Méndez, J M; Jiménez, B E; Barrios, J A

2002-01-01

165

Treatment of coke-oven wastewater with the powdered activated carbon-contact stabilization activated sludge process. Final report  

SciTech Connect

The objective of the study was to determine optimum parameters for the operation of an innovative process train used in the treatment of coke-over wastewater. The treatment process train consisted of a contact-stabilization activated sludge system with powdered activated carbon (PAC) addition, followed by activated sludge nitrification, followed by denitrification in an anoxic filter. The control and operating parameters evaluated during the study were: (a) the average mixed-liquor PAC concentration maintained in the contact-stabilization system, (b) the solids retention time practiced in the contact-stabilization system, and (c) the hydraulic detention time maintained in the contact aeration tank. Three identical treatement process trains were constructed and employed in this study. The coke-oven wastewater used for this investigation was fed to the treatment units at 30% strength. The first part of the study was devoted to determining the interactions between the mixed liquor PAC concentration and the solids retention time in the contact-stabilization tanks. Results showed that optimum overall system performance is attainable when the highest sludge age (30 day) and highest mixed liquor PAC concentration were practiced. During the second phase of the study, all three systems were operated at a 30 day solids retention time while different detention times of 1, 2/3 and 1/3 day were evaluated in the contact tank. PAC addition rates were maintained at the former levels and, consequently, reduced contact times entailed higher mixed liquor carbon concentrations. Once again, the system receiving the highest PAC addition rate of PAC exhibited the best overall performance. This system exhibited no deterioration in process performance as a result of decreased contact detention time. 72 references, 41 figures, 24 tables.

Suidan, M.T.; Deady, M.A.; Gee, C.S.

1983-11-01

166

Occurrence, fate and ecotoxicological assessment of pharmaceutically active compounds in wastewater and sludge from wastewater treatment plants in Chongqing, the Three Gorges Reservoir Area.  

PubMed

The occurrence, removal and ecotoxicological assessment of 21 pharmaceutically active compounds (PhACs) including antibiotics, analgesics, antiepileptics, antilipidemics and antihypersensitives, were studied at four municipal wastewater treatment plants (WWTP) in Chongqing, the Three Gorges Reservoir Area. Individual treatment unit effluents, as well as primary and secondary sludge, were sampled and analyzed for the selected PhACs to evaluate their biodegradation, persistence and partitioning behaviors. PhACs were identified and quantified using high performance liquid chromatography/tandem mass spectrometry after solid-phase extraction. All the 21 analyzed PhACs were detected in wastewater and the target PhACs except acetaminophen, ibuprofen and gemfibrozil, were also found in sludge. The concentrations of the antibiotics and SVT were comparable to or even higher than those reported in developed countries, while the case of other target PhACs was opposite. The elimination of PhACs except acetaminophen was incomplete and a wide range of elimination efficiencies during the treatment were observed, i.e. from "negative removal" to 99.5%. The removal of PhACs was insignificant in primary and disinfection processes, and was mainly achieved during the biological treatment. Based on the mass balance analysis, biodegradation is believed to be the primary removal mechanism, whereas only about 1.5% of the total mass load of the target PhACs was removed by sorption. Experimentally estimated distribution coefficients (<500 L/kg, with a few exceptions) also indicate that biodegradation/transformation was responsible for the removal of the target PhACs. Ecotoxicological assessment indicated that the environment concentrations of single compounds (including sulfadiazine, sulfamethoxazole, ofloxacin, azithromycin and erythromycin-H2O) in effluent and sludge, as well as the mixture of the 21 detected PhACs in effluent, sludge and receiving water had a significant ecotoxicological risk to algae. Therefore, further control of PhACs in effluent and sludge is required before their discharge and application to prevent their introduction into the environment. PMID:24176710

Yan, Qing; Gao, Xu; Chen, You-Peng; Peng, Xu-Ya; Zhang, Yi-Xin; Gan, Xiu-Mei; Zi, Cheng-Fang; Guo, Jin-Song

2014-02-01

167

Evaluation of IAWQ Activated Sludge Model No. 2 using steady-state data from four full-scale wastewater treatment plants  

Microsoft Academic Search

Several new tools, including the Activated Sludge Model No. 2 (ASM No.2) developed by the International Association on Water Quality, are becoming available to analyze the nutrient removal capability of existing wastewater treatment plants (WWTPs). The ASM No. 2 is a potentially inexpensive and effective tool, but its use needs to be evaluated. To solve the differential equations in the

O. Cinar; G. T. Daigger; S. P. Graef

1998-01-01

168

High-rate aerobic treatment of winery wastewater using bioreactors with free and immobilized activated sludge  

Microsoft Academic Search

COD (chemical oxygen demand) removal rate and efficiency of winery wastewater (WW) aerobic treatments were evaluated in an air-bubble column bioreactor using self-adapted microbial populations either free or immobilized on polyurethane particles and in a packed-bed bioreactor immobilized on Raschig rings. The bioreactors were fed continuously for up to 12 months using WW of different origins and with different pollution

Maurizio Petruccioli; JoséCardoso Duarte; Federico Federici

2000-01-01

169

Particulate and colloidal silver in sewage effluent and sludge discharged from British wastewater treatment plants.  

PubMed

Differential filtration was used to measure silver (>2nm) entering and leaving nine sewage treatment plants (STPs). The mean concentration of colloidal (2-450nm) silver, which includes nanosilver, was found to be 12ngL(-1) in the influent and 6ngL(-1) in the effluent. For particulate silver (>450nm) the mean values were 3.3?gL(-1) for influent and 0.08?gL(-1) for effluent. Thus, removal was around 50% and 98% for colloidal and particulate silver respectively. There was no significant difference in performance between the different types of STP investigated (three examples each of activated sludge, biological filter and biological filter with tertiary treatment located across England, UK). In addition, treated sewage sludge samples (biosolids) were taken from several STPs to measure the total silver likely to be discharged to soils. Total silver was 3-14mgkg(-1) DW in the sludge (median 3.6), which if the sludge were added at the recommended rate to soil, would add 11?gkg(-1)yr(-1) to the top 20cm soil layer. Predicted concentrations using the LF2000-WQX model for all the rivers of England and Wales for nanosilver were typically in the 0-1ngL(-1) range but levels up to 4ngL(-1) are possible in a high discharge and low flow scenario. Predicted concentrations for the total particulate forms were mostly below 50ngL(-1) except for a high discharge and low flow scenario where concentrations could reach 135ngL(-1). PMID:25048887

Johnson, Andrew C; Jürgens, Monika D; Lawlor, Alan J; Cisowska, Iwona; Williams, Richard J

2014-10-01

170

Modeling Solar Drying Rate of Wastewater Sludge  

Microsoft Academic Search

Efficient solar drying requires that the drying rate is quantitatively known as a function of the environment and the control. To develop a drying-rate model for wastewater sludge, data were collected at a solar drying installation in Füssen, Germany. In this solar dryer, wet sludge is uniformly spread over a concrete floor under a greenhouse-like transparent cover. The sludge is

Ido Seginer; Markus Bux

2006-01-01

171

Effectiveness of dairy wastewater treatment in a bioreactor based on the integrated technology of activated sludge and hydrophyte system.  

PubMed

The aim of this study was to determine the effectiveness of dairy wastewater treatment in the integrated technology based on the simultaneous use of the activated sludge method (AS) and a hydrophyte system (HS) (AS-HS), in this case, common reed (Phragmites australis) or common cattail (Typha latifolia). Experiments were conducted in an innovative reactor exploited in the fractional-technical scale at the loads of 0.05 mg BOD5/mg.d.m. d (biochemical oxygen demand) and 0.10 mg BOD5/mg.d.m d. The AS--HS enabled improving the removal effectiveness ofbiogenes characterized by concentrations of Ntot., N-NH4 and Ptot. In contrast, the integrated system had no significant reducing effect either on concentrations of organic compounds characterized by BOD5 and chemical oxygen demand parameters or on the structure of AS in the sequencing batch-type reactors. PMID:24701933

Debowski, M; Zieli?ski, M; Krzemieniewski, M; Rokicka, M; Kupczyk, K

2014-01-01

172

Effects of dried wastewater-treatment sludge application on ground-water quality in South Dade County, Florida  

USGS Publications Warehouse

Four test fields in the south Dade agricultural area were studied to determine the effects of sludge application on ground-water quality. Two fields had been cultivated for 10 years or more, and two had not been farmed for at least 10 years. The fields were representative of the area's two soil types (Rockdale and Perrine marl) and two major crop types (row crops and groves). Before the application of sludge, wells upgradient of, within, and downgradient of each field were sampled for possible sludge contaminants at the end of wet and dry seasons. Municipal wastewater treatment sludge from the Dade County Water and Sewe Authority Department was then applied to the fields at varying application rates. The wells at each field were sampled over a 2-year period under different hydrologic conditions for possible sludge-related constituents (specific conductance, pH, alkalinity, nitrogen, phosphorus, total organic carbon, copper, iron, magnesium, manganese, potassium, zinc, arsenic, cadmium, chloride, chromium, lead, mercury, nickel, and sodium). Comparisons were made between water quality in the vicinity of the test fields and Florida Department of Environmental Regulation primary and secondary drinking-water regulations, an between water quality upgradient of, beneath, and downgradient of the fields. Comparisons between presludge and postsludge water quality did not indicate any improvement because of retention of agrichemicals by the sludge nor did they indicate any deterioration because of leaching from the sludge. Comparisons of water quality upgradient of the fields to water quality beneath and downgradient of the fields also did not indicate any changes related to sludge. Florida Department of Environmental Regulation primary and secondary drinking-water regulations wer exceeded at the Rockdale maximum-application field by mercury (9.5 ug/L (micrograms per liter)), and the Perrine marl maximum-application field by manganese (60 ug/L) and lead (85 ug/L), and at the Perrine marl row-crop field by mercury (5.2 ug/L). All other exceedances were either in presludge or upgradient samples, or they were for constituents or properties, such as iron and color, which typically exceed standards in native ground water. Acid-extractable and base-neutral compounds, volatile organic compounds, chlorophenoxy herbicides, organophosphorus insecticides, and organochlorine compounds were analyzed for one shallow well at each field twice annually. Those compounds that equaled or exceeded the detection limit after sludge was applied included benzene (0.3 and 1.2 ug/L), chloroform (0.2 and 0.3 ug/L), bis(2-Ethylhexyl)phthalate (29 and 42 ug/L), methylene chloride (14 ug/L), tolulene (0.2, 0.4, 0.5, 1.3, and 4.4 ug/L), 1, 1,1-trichloroethana (0.6 ug/L), trichloroethylene (0.3 ug/L), 2.4-D (0.01 ug/L), and xylene (0.3 ug/L). It ws not possible to ascertain the origin of these compounds becuase they are available from sources other than sludge.

Howie, Barbara

1992-01-01

173

Wastewater Treatment  

NSDL National Science Digital Library

Water-technology.net web site for the water industry contains links to many sites for detailed information on industrial and municipal wastewater treatment plants as well as water supply and transmission. Also find information on current news releases, expos, conferences and much more.

2008-10-13

174

Monitoring of total metal concentration in sludge samples: case study for the mechanical-biological wastewater treatment plant in Velika Gorica, Croatia.  

PubMed

In this paper, monitoring of total metal concentration in sludge samples from wastewater treatment process is elaborated. The presented results summarize the analyses of sludge samples in a period from 2008 to 2012. Possible sources of pollutions are given. Primarily, waste solid samples were collected from different pretreatment steps: (A) coarse grid, (B) fine grid and (C) aerated sand grease grid. Samples of A and B followed a repeatable pattern in 2008 and 2010. According to the results from 2008, samples of C contained measurable concentration of the following metals (mg/kg dry matter): Zn (21), Ni (1.05) and Ba (14.9). Several types of sludge samples were analyzed: fresh raw sludge (PS; 6-12 hour old), the sludge from the digester for anaerobic sludge treatment (DS; 48-72 hour old), samples from lagoons where the sludge is temporarily deposited (DOS and DOSold; 30-120 days) and sludge samples from agricultural areas (AA; aged over 180 days). Additionally, samples of dehydrated sludge (DEHS and DEHSold; 90-180 days) were collected upon construction of equipment for sludge dehydration in 2011. An analysis of total metal concentrations for Cu, Zn, Cr, Pb, Ni, Hg, Cd, Ba, As, Se, Sb, Co, Mo, Fe and Mn was performed by flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). The most recent results (year 2011) indicated a high concentration of heavy metals in PS samples, exceeding the MCLs (mg/kg dry matter): Cu (2122), Zn (5945), Hg (13.67) and Cd (6.29). In 2012 (until July), only a concentration of Cu exceeded MCL (928.75 and 1230.5 in DS and DEHS, respectively). A composition of sludge was variable through time, offering the limited possibility for future prediction. The sludge is being considered as a hazardous waste and a subject of discussion regarding disposal. PMID:23376512

Filipovi?, Josip; Gr?i?, Ivana; Bermanec, Vladimir; Kniewald, Goran

2013-03-01

175

Utilization of Soil Invertebrates in Stabilization, Decontamination and Detoxification of Residual Sludges from Treatment of Wastewater.  

National Technical Information Service (NTIS)

This research addresses the problem of reducing the organic matter content in sludge without destroying the biological value of sludge as a potential contribution to the soil ecosystem. The authors propose that earthworms can be used effectively in a mana...

R. Hartenstein M. J. Mitchell

1977-01-01

176

The re-use of Waste-Activated Sludge as part of a "zero-sludge" strategy for wastewater treatments in the pulp and paper industry.  

PubMed

The possibility of introducing the thermo-alkali hydrolysis of Waste-Activated Sludge (WAS) was investigated, in order to enable the use of its solid residue as a raw material in cardboard production and the use of its liquid portion for anaerobic digestion in an UASB reactor. The evaluation of the hydrolysis at pH>12 and T=70°C showed that the microbe cells were disrupted with more than 90% efficiency in less than 2h. The solid portion was hygienised, therefore making it possible to integrate it into the cardboard production as a raw material for less demanding cardboards. Up to 6% addition of the liquid portion of hydrolysed WAS to wastewater decreased the specific biogas production in a pilot-scale UASB from 0.236 to 0.212 m(3)/kg(COD), while the efficiency of the COD removal decreased from 80.4% to 76.5%. These values still guarantee an adequate treatment of the wastewater and an increased biogas production by 16%. PMID:24215770

Kaluža, Leon; Suštarši?, Matej; Rutar, Vera; Zupan?i?, Gregor D

2014-01-01

177

[Amelioration effects of wastewater sludge biochars on red soil acidity and their environmental risk].  

PubMed

Biochars were prepared from wastewater sludge from two wastewater treatment plants in Nanjing using a pyrolysis method at 300, 500 and 700 degrees C. The properties of the biochars were measured, and their amelioration effects on the acidity of a red soil and environmental risk of application of sludge biochars were examined to evaluate the possibility of agricultural application of wastewater sludge biochars in red soils. Results indicated that incorporation of both sludge and sludge biochar increased soil pH due to the alkalinity of sludge and sludge biochar, and the mineralization of organic N and nitrification of ammonium N from wastewater sludge induced soil pH fluctuated during incubation. The amelioration effects of biochars generated at 500 and 700 degrees C on the soil were significantly greater than that of sludge significantly. Sludge and sludge biochar contain ample base cations of Ca2+, Mg2+, K+ and Na+ and thus incorporation of sludge and sludge biochar increased the contents of soil exchangeable base cations and decreased soil exchangeable aluminum and H+. Contents of heavy metals in sludge biochars were greater than these in their feedstock sludge, while the contents of Cu, Pb, Ni and As in sludge biochars were lower than the standard values of heavy metals were wastewater sludge for agricultural use in acid soils in China except for Zn and Cd. The contents of available forms of heavy metals in the biochars generated from sludge from Chengdong wastewater treatment plant was lower than these in the corresponding sludge, suggesting that pyrolysis proceed decreased the activity of heavy metals in wastewater sludge. After 90-day incubation of the soil with sludge and sludge biochar, the differences in the contents of soil available heavy metals were not significant between the biochars and their feedstock sludge from Jiangxizhou wastewater treatment plant, and the contents in the treatments with biochars added was lower than these in the treatments with the corresponding sludge from Chengdong wastewater treatment plant for most of heavy metals. It can be concluded that the biochars from wastewater sludge could be used as soil amendments to adjust soil acidity. Application of sludge biochars did not increase activity and availability of heavy metals compared with direct incorporation of the sludge. PMID:23233992

Lu, Zai-Liang; Li, Jiu-Yu; Jiang, Jun; Xu, Ren-Kou

2012-10-01

178

UNITED STATES PRACTICE IN SLUDGE TREATMENT AND DISPOSAL  

EPA Science Inventory

Sludge treatment and disposal problems and costs grow with increased concern about the quality of wastewater treatment. As standards for effluent quality in the United States have become stricter, the problems of sludge treatment and disposal have grown disproportionately. Today ...

179

Metagenomic analysis of cadmium and copper resistance genes in activated sludge of a tannery wastewater treatment plant.  

PubMed

In order to comprehensively characterize the copper and cadmium resistance in activated sludge of a tannery wastewater treatment plant, a resistance protein database of the two heavy metals was manually created by retrieving annotated sequences and related information from the public databases and published literatures. The metagenomic DNA was extracted from the activated sludge for Illumina high-throughput sequencing, and the obtained 11,973,394 clean reads (1.61 Gb) were compared against the established databases using BLAST tool. Annotations of the BLAST hits showed that 222 reads (0.019 per thousand) and 197 reads (0.016 per thousand) were identified as copper and cadmium resistance genes, respectively. Among the identified cadmium resistance genes, czcA encoding cobalt-zinc-cadmium resistance protein had the highest abundance (83 reads, 0.0069 per thousand), which was further confirmed by annotation of the open reading frames predicted with the assembly contigs. Among the copper resistance genes, copA (66 reads, 0.0055 per thousand) was most abundant, followed by copK and cusR. Alignment against the Clusters of Orthologous Groups (COG) database also suggested that 87.26% of the matched reads were grouped in COG0474 (cation transport ATPase). This study may be practically helpful for exploring various functional genes in the environment using high-throughput sequencing and bioinformatics methods. PMID:24620608

Jia, Shuyu; Wang, Zhu; Zhang, Xu-Xiang; Liu, Bo; Li, Weixin; Cheng, Shupei

2013-04-01

180

Probabilistic assessment of environmental exposure to the polycyclic musk, HHCB and associated risks in wastewater treatment plant mixing zones and sludge amended soils in the United States.  

PubMed

The objective of this work was to conduct an environmental risk assessment for the consumer use of the polycyclic musk, HHCB (CAS No. 1222-05-5) in the U.S. focusing on mixing zones downstream from municipal wastewater treatment plants (WWTPs) and sludge amended soils. A probabilistic exposure approach was utilized combining statistical distributions of effluent and sludge concentrations for the U.S. WWTPs with distributions of mixing zone dilution factors and sludge loading rates to soil to estimate HHCB concentrations in surface waters and sediments below WWTPs and sludge amended soils. These concentrations were then compared to various toxicity values. Measured concentrations of HHCB in effluent and sludge from a monitoring program of 40 WWTPs across the U.S. formed the basis for estimating environmental loadings. Based upon a Monte Carlo analysis, the probability of HHCB concentrations being below the PNEC (predicted no effect concentration) for pelagic freshwater organisms was greater than or equal to 99.87% under both mean and low flow regimes. Similarly, the probability of HHCB concentrations being less than the PNEC for freshwater sediment organisms was greater than or equal to 99.98%. Concentrations of HHCB in sludge amended soils were estimated for single and repeated annual sludge applications with tilling of the sludge into the soil, surface application without tilling and a combination reflecting current practice. The probability of soil HHCB concentrations being below the PNEC for soil organisms after repeated sludge applications was 94.35% with current sludge practice. Probabilistic estimates of HHCB exposures in surface waters, sediments and sludge amended soils are consistent with the published values for the U.S. In addition, the results of these analyses indicate that HHCB entering the environment in WWTP effluent and sludge poses negligible risk to aquatic and terrestrial organisms in nearly all exposure scenarios. PMID:24802072

Federle, Thomas; Sun, Ping; Dyer, Scott; Kiel, Brian

2014-09-15

181

Use of dewatered alum sludge as main substrate in treatment reed bed receiving agricultural wastewater: Long-term trial  

Microsoft Academic Search

This study aims to explore a novel application of dewatered alum sludge cakes (DASC) as the main medium in a single model reed bed to treat phosphorus-rich animal farm wastewater under “tidal flow” operation on a long-term basis. It is expected that the cakes act as the carrier for developing biofilm and also serve as adsorbent to enhance phosphorus (P)

Y. Q. Zhao; X. H. Zhao; A. O. Babatunde

2009-01-01

182

Effects of High-Stress Polymer Conditioning on the Filterability of Water and Wastewater Sludges.  

National Technical Information Service (NTIS)

Tests were conducted on samples of alum, activated, and primary sludges obtained from water and wastewater treatment plants in southwest Virginia. The purpose of the testing was to determine if the sludges could be conditioned with polymers and still prov...

C. P. Werle

1983-01-01

183

Predicting concentrations of trace organic compounds in municipal wastewater treatment plant sludge and biosolids using the PhATE™ model.  

PubMed

This article presents the capability expansion of the PhATE™ (pharmaceutical assessment and transport evaluation) model to predict concentrations of trace organics in sludges and biosolids from municipal wastewater treatment plants (WWTPs). PhATE was originally developed as an empirical model to estimate potential concentrations of active pharmaceutical ingredients (APIs) in US surface and drinking waters that could result from patient use of medicines. However, many compounds, including pharmaceuticals, are not completely transformed in WWTPs and remain in biosolids that may be applied to land as a soil amendment. This practice leads to concerns about potential exposures of people who may come into contact with amended soils and also about potential effects to plants and animals living in or contacting such soils. The model estimates the mass of API in WWTP influent based on the population served, the API per capita use, and the potential loss of the compound associated with human use (e.g., metabolism). The mass of API on the treated biosolids is then estimated based on partitioning to primary and secondary solids, potential loss due to biodegradation in secondary treatment (e.g., activated sludge), and potential loss during sludge treatment (e.g., aerobic digestion, anaerobic digestion, composting). Simulations using 2 surrogate compounds show that predicted environmental concentrations (PECs) generated by PhATE are in very good agreement with measured concentrations, i.e., well within 1 order of magnitude. Model simulations were then carried out for 18 APIs representing a broad range of chemical and use characteristics. These simulations yielded 4 categories of results: 1) PECs are in good agreement with measured data for 9 compounds with high analytical detection frequencies, 2) PECs are greater than measured data for 3 compounds with high analytical detection frequencies, possibly as a result of as yet unidentified depletion mechanisms, 3) PECs are less than analytical reporting limits for 5 compounds with low analytical detection frequencies, and 4) the PEC is greater than the analytical method reporting limit for 1 compound with a low analytical detection frequency, possibly again as a result of insufficient depletion data. Overall, these results demonstrate that PhATE has the potential to be a very useful tool in the evaluation of APIs in biosolids. Possible applications include: prioritizing APIs for assessment even in the absence of analytical methods; evaluating sludge processing scenarios to explore potential mitigation approaches; using in risk assessments; and developing realistic nationwide concentrations, because PECs can be represented as a cumulative probability distribution. Finally, comparison of PECs to measured concentrations can also be used to identify the need for fate studies of compounds of interest in biosolids. PMID:22162313

Cunningham, Virginia L; D'Aco, Vincent J; Pfeiffer, Danielle; Anderson, Paul D; Buzby, Mary E; Hannah, Robert E; Jahnke, James; Parke, Neil J

2012-07-01

184

MWIP: Surrogate formulations for thermal treatment of low-level mixed waste. Part 4, Wastewater treatment sludges  

SciTech Connect

The category of sludges, filter cakes, and other waste processing residuals represent the largest volume of low-level mixed (hazardous and radioactive) wastes within the US Department of Energy (DOE) complex. Treatment of these wastes to minimize the mobility of contaminants, and to eliminate the presence of free water, is required under the Federal Facility Compliance Act agreements between DOE and the Environmental Protection Agency. In the text, we summarize the currently available data for several of the high priority mixed-waste sludge inventories within DOE. Los Alamos National Laboratory TA-50 Sludge and Rocky Flats Plant By-Pass Sludge are transuranic (TRU)-contaminated sludges that were isolated with the use of silica-based filter aids. The Oak Ridge Y-12 Plant West End Treatment Facility Sludge is predominantly calcium carbonate and biomass. The Oak Ridge K-25 Site Pond Waste is a large-volume waste stream, containing clay, silt, and other debris in addition to precipitated metal hydroxides. We formulate ``simulants`` for the waste streams described above, using cerium oxide as a surrogate for the uranium or plutonium present in the authentic material. Use of nonradiological surrogates greatly simplifies material handling requirements for initial treatability studies. The use of synthetic mixtures for initial treatability testing will facilitate compositional variation for use in conjunction with statistical design experiments; this approach may help to identify any ``operating window`` limitations. The initial treatability testing demonstrations utilizing these ``simulants`` will be based upon vitrification, although the materials are also amenable to testing grout-based and other stabilization procedures. After the feasibility of treatment and the initial evaluation of treatment performance has been demonstrated, performance must be verified using authentic samples of the candidate waste stream.

Bostick, W.D.; Hoffmann, D.P.; Stevenson, R.J.; Richmond, A.A. [Oak Ridge National Lab., TN (United States); Bickford, D.F. [Westinghouse Savannah River Co., Aiken, SC (United States)

1994-01-01

185

Treatment of Coal-Conversion Wastewater with the Powdered Activated Carbon-Contact-Stabilization Activated-Sludge Process. First Annual Technical Progress Report, February 1, 1981-July 31, 1981.  

National Technical Information Service (NTIS)

The scope of work of the present reseach project is to evaluate the effectiveness of the powdered activated carbon-contact stabilization activated sludge process in the treatment of a coke oven wastewater. Nitrification and subsequent denitrification of t...

M. T. Suidan C. S. Gee M. A. Deady M. Pirbazari

1981-01-01

186

Engineering Assessment of Vermicomposting Municipal Wastewater Sludges.  

National Technical Information Service (NTIS)

Vermicomposting -- the biological degradation of organic matter that occurs as earthworms feed on waste materials -- has been advocated by some as a means of stabilizing and disposing of municipal wastewater sludges. Vermicomposting is being attempted on ...

1981-01-01

187

ENGINEERING ASSESSMENT OF VERMICOMPOSTING MUNICIPAL WASTEWATER SLUDGES  

EPA Science Inventory

Vermicomposting -- the biological degradation of organic matter that occurs as earthworms feed on waste materials -- has been advocated by some as a means of stabilizing and disposing of municipal wastewater sludges. Vermicomposting is being attempted on an experimental scale, th...

188

The use of Ferrate(VI) technology in sludge treatment  

Microsoft Academic Search

Sludge in large quantity is generated as byproducts of wastewater treatment processes. Various approaches have been taken to treat sludge, such as land-filling, ocean dumping, or recycling for beneficial purposes. In the USA, about 60% of sludge generated is land applied as a soil conditioner or fertilizer. Due to increasing public concern on the safety of land-applied sludge, various sludge

JiaQian Jiang; Virender K Sharma

2008-01-01

189

Biological Treatment of Dairy Wastewater in an Upflow Anaerobic Sludge-Fixed Film Bioreactor  

Microsoft Academic Search

An upflow anaerobic sludge-fixed film (UASFF) reactor is a granular sludge bioreactor that was used for the rapid biological conversion of organic matter to biogas with the aids of aggregated microbial consortium. The major problem associated with the conventional UASB reactor is the long duration for startup period. In this study, UASFF bioreactor with tubular flow behavior was developed in

G. D. Najafpour; M. Asadi; M. B. Ghasemi

190

Sewage sludge management for phosphorus recovery as struvite in EBPR wastewater treatment plants.  

PubMed

The influence of separate and mixed thickening of primary and secondary sludge on struvite recovery was studied. Phosphorus precipitation in the digester was reduced from 13.7 g of phosphorus per kg of treated sludge in the separate thickening experiment to 5.9 in the mixed thickening experiment. This lessening of the uncontrolled precipitation means a reduction of the operational problems and enhances the phosphorus availability for its later crystallization. High phosphorus precipitation and recovery efficiencies were achieved in both crystallization experiments. However, mixed thickening configuration showed a lower percentage of phosphorus precipitated as struvite due to the presence of high calcium concentrations. In spite of this low percentage, the global phosphorus mass balance showed that mixed thickening experiment produces a higher phosphorus recovery as struvite per kg of treated sludge (i.e., 3.6 gP/kg sludge vs. 2.5 gP/kg sludge in separate thickening). PMID:17976981

Pastor, L; Marti, N; Bouzas, A; Seco, A

2008-07-01

191

Microbial community structure and population dynamics of granules developed in expanded granular sludge bed (EGSB) reactors for the anaerobic treatment of low-strength wastewater at low temperature  

Microsoft Academic Search

The anaerobic biological treatment of sucrose-based, low-strength wastewater was investigated in expanded granular sludge bed (EGSB) reactors at low temperatures over a 300-day trial period. During the trial, the operating temperature was lowered in a stepwise manner from 20°C to 5°C. As a result, the reactors exhibited sufficient performances until 10°C operation. The COD removal rate was 3.1–3.8 kgCOD m

Ikuo Tsushima; Wilasinee Yoochatchaval; Hiroki Yoshida; Nobuo Araki; Kazuaki Syutsubo

2010-01-01

192

Use of an aerobic selector to overcome filamentous bulking in an activated sludge wastewater treatment plant.  

PubMed

An urban wastewater treatment plant (WWTP) with two different parallel lines of treatment and located in the north of Portugal was studied during four months, following recurrent episodes of filamentous bulking caused by Sphaerotilus natans and eventual occurrences of Nocardioforms and Type 1863. An aerobic selector was introduced in both lines in the beginning of the studied period, suppressed in one of the lines during six weeks, and then put into operation again until the end of the study. A total of 14 filamentous bacteria morphotypes were identified. The results showed that the presence of an aerobic biological selector in continuous operation prevented the overgrowth of the filamentous Type 1863, of Nocardioforms and, in particular, of S. natans. Simultaneously, it allowed lowering the oxygen levels in the aeration tanks without negative consequences in the overall performance of the WWTP, namely bulking occurrence. Dissolved oxygen (DO) in the aeration tank varied initially between 2 and 3 mg/L, but the introduction of the selector enabled to lower it to 1-1.5 mg/L in the aeration tank and around 0.5 mg/L in the selector. A significant energy save was allowed, even considering the aeration of the selector. The results are more relevant if one considers the fact that the main cause of the bulking problems in this WWTP was the overgrowth of S. natans, a filamentous bacterium known to be stimulated by low DO levels. PMID:24701952

Ferreira, Vânia; Martins, Catarina; Pereira, Maria Olívia; Nicolau, Ana

2014-01-01

193

Microwave and thermal pretreatment as methods for increasing the biogas potential of secondary sludge from municipal wastewater treatment plants.  

PubMed

In the present study, the sludge was pretreated with microwave irradiation and low-temperature thermal method, both conducted under the same temperature range (30-100°C). Microwave pretreatment was found to be superior over the thermal treatment with respect to sludge solubilization and biogas production. Taking into account the specific energy demand of solubilization, the sludge pre-treated at 60-70°C by microwaves of 900 W was chosen for further experiments in continuous mode, which was more energetically sustainable compared to lower value (700 W) and thermal treatment. Continuous biogas reactor experiments indicated that pre-treated sludge (microwave irradiation: 900 W, temperature: 60-70°C) gave 35% more methane, compared to untreated sludge. Moreover, the results of this study clearly demonstrated that microwave pretreated sludge showed better degree of sanitation. PMID:23500587

Kuglarz, Mariusz; Karakashev, Dimitar; Angelidaki, Irini

2013-04-01

194

Reducing sludge production and the domination of Comamonadaceae by reducing the oxygen supply in the wastewater treatment procedure of a food-processing factory.  

PubMed

Sludge production was reduced remarkably by reducing the dissolved oxygen supply to less than 1 mg/l in the conventional wastewater treatment procedure of a food-processing factory that produced 180 m(3) of wastewater of biochemical oxygen demand (BOD) of about 1,000 mg/l daily. DNA was extracted from the sludge and subjected to PCR amplification. The PCR product was cloned into a plasmid and sequenced. Estimation of the resident bacterial distribution by 16S rDNA sequences before and after improvement of the system suggested a remarkable gradual change in the major bacterial population from Anaerolinaeceae (15.6%) to Comamonadaceae (52.3%), members of denitrifying bacteria of Proteobacteria. Although we did not directly confirm the ability of denitrification of the resulting sludge, a change in the major final electron acceptors from oxygen to nitrate might explain the reduction in sludge production in a conventional activated sludge process when the oxygen supply was limitted. PMID:17341826

Sadaie, Tamiko; Sadaie, Aya; Takada, Masao; Hamano, Keiichi; Ohnishi, Junichi; Ohta, Niji; Matsumoto, Kouji; Sadaie, Yoshito

2007-03-01

195

Wastewater Treatment  

NSDL National Science Digital Library

Before this activity the students will have heard about groundwater and water resources through lecture to give them a background on where our drinking water comes from. The activity involves a tour of the local wastewater treatment plant where the students told about the treatment processes and shown the treatment facility. They are also introduced to the water quality testing done at the plans and they learn about the energy usage/management at the plant. As part of the activity they write up a paper on the processes in the treatment process from the time water enters the plant until it exits. The students are encouraged before hand to ask questions to ensure that they gather the needed information. This always means that each tour has a slightly different content based on these questions.

Pedersen, Bianca

196

Conversion of Municipal Wastewater Treatment Plant Residual Sludges into Earthworm Castings for Use as Topsoil.  

National Technical Information Service (NTIS)

This experiment demonstrates the physical abilities of earthworms to convert sizable amounts of municipal sewage sludges into worm manure, a stabilized soil known as castings. The process of composting wastes with domesticated earthworms under controlled ...

J. E. Collier

1978-01-01

197

Application of hydrothermal oxidation and alkaline hydrothermal gasification for the treatment of sewage sludge and pharmaceutical wastewaters.  

PubMed

Hydrothermal treatment involving the oxidation and gasification of sewage sludge and pharmaceutical wastewater samples has been carried out in batch autoclave reactor. The efficiency of the oxidation processes measured in terms of total organic carbon (TOC) and total solids (TS) removal showed that effective sample treatments were achieved at moderately low temperatures of 350-450 degrees C. More than 90% TOC removal was achieved in all samples, with samples with lower organic contents reaching above 99% TOC removal. A maximum of 78% TS removal was achieved due to the high initial ash contents of the samples. Alkaline hydrothermal gasification of the samples with very high TOC contents yielded gas products rich in hydrogen gas and methane. Due to high concentrations of acetonitrile in some of the samples, the yields of methane were high, giving calorific values of the product gases of up to 35 MJ/m3 in some samples; however, the gasification process resulted in lower TOC destruction compared to the oxidation process. PMID:23530368

Onwudili, Jude A; Radhakrishnan, Pushpa; Williams, Paul T

2013-01-01

198

Bacteriophage-based biocontrol of biological sludge bulking in wastewater.  

PubMed

In a previous paper, the first ever application of lytic bacteriophage (virus)-mediated biocontrol of biomass bulking in the activated sludge process using Haliscomenobacter hydrossis as a model filamentous bacterium was demonstrated. In this work we extended the biocontrol application to another predominant filamentous bacterium, Sphaerotilus natans, notoriously known to cause filamentous bulking in wastewater treatment systems. Very similar to previous study, one lytic bacteriophage was isolated from wastewater that could infect S. natans and cause lysis. Significant reduction in sludge volume index and turbidity of the supernatant was observed in batches containing S. natans biomass following addition of lytic phages. Microscopic examination confirmed that the isolated lytic phage can trigger the bacteriolysis of S. natans. This extended finding further strengthens our hypothesis of bacteriophage-based biocontrol of overgrowth of filamentous bacteria and the possibility of phage application in activated sludge processes, the world's widely used wastewater treatment processes. PMID:21829092

Choi, Jeongdong; Kotay, Shireen Meher; Goel, Ramesh

2011-01-01

199

Respirometric Evaluation of Strong Wastewater Activated Sludge Treatment for a Complex Chemical Industry  

Microsoft Academic Search

\\u000a This study deals with respirometric modeling of biodegradation of complex organic matter generated from a chemical industry.\\u000a Evaluation with a multi-degradation model indicated that organic matter in raw wastewater has four types of biodegradable\\u000a components having different biodegradation characteristics. The model evaluation of batch respirogram indicated that the acclimated\\u000a biomass exhibited a delayed response after the addition of raw wastewater

E. Ubay Cokgor; G. Insel; E. Aydin; S. Ozdemir; D. Orhon

200

Effective water content reduction in sewage wastewater sludge using magnetic nanoparticles.  

PubMed

The present work compares the use of three flocculants for sedimentation of sludge and sludge water content from sewage wastewater i.e. magnetic iron oxide nanoparticles (MION), ferrous sulfate (chemical) and Moringa crude extract (protein). Sludge water content, wet/dry weight, turbidity and color were performed for, time kinetics and large-scale experiment. A 30% reduction of the sludge water content was observed when the wastewater was treated with either protein or chemical coagulant. The separation of sludge from wastewater treated with MION was achieved in less than 5min using an external magnet, resulted in 95% reduction of sludge water content. Furthermore, MION formed denser flocs and more than 80% reduction of microbial content was observed in large volume experiments. The results revealed that MION is efficient in rapid separation of sludge with very low water content, and thus could be a suitable alternative for sludge sedimentation and dewatering in wastewater treatment processes. PMID:24378779

Lakshmanan, Ramnath; Kuttuva Rajarao, Gunaratna

2014-02-01

201

Combined activated sludge with partial nitrification (AS/PN) and anammox processes for treatment of seafood processing wastewater.  

PubMed

An activated sludge process with partial nitrification (AS/PN) in combination with anaerobic ammonium oxidation (Anammox) process for treatment of seafood processing wastewater was developed and investigated in this research. Operating conditions of AS/PN process for coupling with Anammox process were identified as pH between 7.7-8.2 and DO as 0.5-0.9 mg L(-1) to achieve over 85% COD removal as well as partial nitrification. The developed AS/PN process could produce almost equal concentration of ammonium and nitrite nitrogen in the effluent which was highly suitable for the Anammox process. Near complete removal of ammonium and nitrite was achieved during steady state Anammox process operation. Maximum nitrogen removal rate for the Anammox process was found to be 0.6 kg N m(- 3) d(-1). Microorganisms involved in both AS/PN and Anammox processes were identified using in situ hybridization and polymerase chain reaction techniques. The result 16S rDNA revealed 94% homology to Candidatus "Brocadia fulgida." PMID:18584436

Lamsam, Apipong; Laohaprapanon, Sawanya; Annachhatre, Ajit P

2008-08-01

202

Treatment of fish processing wastewater in a one- or two-step upflow anaerobic sludge blanket (UASB) reactor.  

PubMed

The performance of one-step UASB reactors treating fish processing wastewater of different lipid levels was determined using artificially generated influent simulating that of the canning of sardines and tuna. The organic loading rates (OLR) and the hydraulic retention times (HRT) were 5-8 g COD.l(-1).d(-1) and 11-12 hours, respectively. In treating a wastewater that contains 3-4 g.l(-1) total COD of which 5-9% was lipids, the COD removal and conversion to methane were ca.78% and 61%, respectively. In treating a wastewater with a higher lipid content (ca. 47% of the total COD), the total COD removed and converted to methane were 92% and 47%, respectively. A considerable part of the influent total COD was removed via adsorption on reactor surfaces and sludge particles. The adsorption of lipids on sludge particles threatens the stability of the UASB operation. Thus, the performance of a first-step UASB reactor in removing suspended solids (SS) from a "high-lipid" wastewater was also determined in this study. PMID:12188546

Palenzuela-Rollon, A; Zeeman, G; Lubberding, H J; Lettinga, G; Alaerts, G J

2002-01-01

203

EVALUATION OF SORPTION ISOTHERMS FOR SELECTED AZO DYES AS PREDICTORS OF FATE IN AN ACTIVATED SLUDGE WASTEWATER TREATMENT PROCESS  

EPA Science Inventory

Azo dyes are of concern because of their widespread production and use and their potential adverse environmental and health impacts. Environmental exposure is normally via aqueous effluents of manufacturing and use industries, and treatment is at municipal wastewater treatment pl...

204

DEWATERING WASTEWATER TREATMENT SLUDGE BY CLATHRATE FREEZING: A BENCH-SCALE FEASIBILITY STUDY  

EPA Science Inventory

Laboratory studies were performed to prove the concept and feasibility for a novel technology to dewater sludges. This involves the formation of solid hydrate crystals of water and specific clathrate-forming agents followed by separation of the hydrate crystal solids from the slu...

205

Psychrophilic (6--15 {degree}C) high-rate anaerobic treatment of malting wastewater in a two-module expanded granular sludge bed system  

SciTech Connect

Psychrophilic (6--15 C) anaerobic treatment of malting wastewater was investigated. A two-module expanded granular sludge bed reactor system with a total volume of 140 dm{sup 3} was used to treat malting wastewater having a soluble and total chemical oxygen demand (COD) between 233 and 1778 mg dm{sup {minus}3} and between 317 and 4422 mg dm{sup {minus}3}, respectively. The removal efficiencies at 6 C were 47 and 71% of the soluble and volatile fatty acids (VFA) COD, at organic loading rates (OLR) ranging between 3.3 and 5.8 kg of COD m{sup {minus}3} day{sup {minus}1}. The removal efficiencies at 10--15 C were 67--78 and 90--96% of the soluble and VFA COD at an OLR between 2.8 and 12.3 kg of COD m{sup {minus}3} day{sup {minus}1}. The specific methanogenic activity of the sludge present in each module increased 2--3-fold during system operation for 400 days. The relatively high concentration of suspended solids in the influent (25% of the total COD) caused a deterioration of the sludge bed in the first reactor module. This was aggravated by excessive growth of acidifying biomass, which persisted in the first module sludge bed and resulted in granular sludge flotation. However, the second module could accommodate the increased OLR, this providing a very high effluent quality (soluble COD < 200 mg dm{sup {minus}3}) of the total system. The stability of module 1 concerning suspended solids could be restored by presettling the wastewater.

Rebac, S.; Lier, J.B. van; Lens, P.; Cappellen, J. van; Vermeulen, M.; Stams, A.J.M.; Lettinga, G. [Wageningen Agricultural Univ. (Netherlands)] [Wageningen Agricultural Univ. (Netherlands); Dekkers, F.; Swinkels, K.T.M. [Bavaria B.V., Lieshout (Netherlands)] [Bavaria B.V., Lieshout (Netherlands)

1998-11-01

206

Transport and fate of silver as polymer-stabilised nanoparticles and ions in a pilot wastewater treatment plant, followed by sludge digestion and disposal of sludge/soil mixtures: A case study.  

PubMed

A case study of transport and changes in properties of polymer-stabilised Ag NPs is presented in this paper investigating their interaction in different treatment steps within a fully realistic pilot wastewater treatment plant (WWTP), in anaerobic digested sludge, and in soil/sludge mixtures. The fate of the same Ag NPs was tracked in these environments, hence taking the history of the Ag NPs into account. The results show that most of the Ag NPs end up in the sludge (80-100%), also after anaerobically digestion. Furthermore, the fraction of silver in the supernatant was very low after 48 h incubation with silver-containing digested sludge mixed with different soil types. However, when Ag NPs were added directly to the sludge/soil mixture, soluble silver was present in the supernatant with sandy soil, but not with clayey soil. In all, generated findings show that risk assessments and toxicological studies of Ag NPs suspensions must take into account possible chemical and particle transformations upon environmental entry, as silver in general become less soluble when transported to WWTPs and interacting with sludge, and soil. PMID:25072774

Hedberg, Jonas; Baresel, Christian; Odnevall Wallinder, Inger

2014-10-15

207

Treatment and reuse of coal conversion wastewaters  

Microsoft Academic Search

This paper presents a synopsis of recent experimental activities to evaluate processing characteristics of coal conversion wastewaters. Treatment studies have been performed with high-BTU coal gasification process quench waters to assess enhanced removal of organic compounds via powdered activated carbon-activated sludge treatment, and to evaluate a coal gasification wastewater treatment train comprised of sequential processing by ammonia removal, biological oxidation,

Luthy

1980-01-01

208

Commissioning of the gigantic anaerobic sludge digesters at the wastewater treatment plant of Athens.  

PubMed

The pre-commissioning strategy, the start-up procedure and the analytical data obtained during the commissioning period for the first of the four new anaerobic gigantic digesters, with active volume of 10,000 m3 each, are presented in this paper. The digester was initially filled up with water, and the temperature was raised to 36 +/- 1 degrees C. Then, a total amount of 1,860 m3 of digested primary sludge was transferred, in four equal daily batches, into the digester from neighbouring digesters, performing routine operation. Following this, the digester was gradually fed with fresh primary thickened sludge, up to the point that the retention time reached approximately 20 d. A number of significant operational parameters (pH, alkalinity, total and volatile solids concentration, volatile fatty acids concentration, biogas production rate and composition) were monitored several times per day, and the appropriate adjustments were performed in order to achieve stable operation. The time duration of the whole process was about two and a half months. Later on, the digester was supplied with a mixture of primary and biological sludge. PMID:18613612

Gikas, P

2008-02-01

209

Municipal Wastewater Sludge Combustion Technology.  

National Technical Information Service (NTIS)

The publication describes and evaluates the various municipal sludge combustion systems. It also emphasizes the necessity for considering and evaluating the costs involved in the total sludge management train, including dewatering, combustion, air polluti...

1985-01-01

210

MUNICIPAL WASTEWATER SLUDGE COMBUSTION TECHNOLOGY  

EPA Science Inventory

The publication describes and evaluates the various municipal sludge combustion systems. It also emphasizes the necessity for considering and evaluating the costs involved in the total sludge management train, including dewatering, combustion, air pollution control, and ash dispo...

211

Treatment of a chocolate industry wastewater in a pilot-scale low-temperature UASB reactor operated at short hydraulic and sludge retention time.  

PubMed

The aim of this work was to evaluate the performance of a 244-L pilot-scale upflow anaerobic sludge blanket (UASB) reactor during the treatment of chocolate-processing industry wastewater under low-temperature conditions (18 ± 0.6 °C) for approximately 250 d. The applied organic loading rate (OLR) was varied between 4 and 7 kg/m(3)/d by varying the influent soluble chemical oxygen demand (CODsol), while keeping the hydraulic retention time constant (6.4 ± 0.3 h). The CODsol removal efficiency was low (59-78%). The measured biogas production increased from 240 ± 54 to 431 ± 61 L/d during the experiments. A significant linear correlation between the measured biogas production and removed OLR indicated that 81.69 L of biogas were produced per kg/m(3) of CODsol removed. Low average reactor volatile suspended solids (VSS) (2,700-4,800 mg/L) and high effluent VSS (177-313 mg/L) were derived in a short sludge retention time (SRT) (4.9 d). The calculated SRT was shorter than those reported in the literature, but did not affect the reactor's performance. Average sludge yield was 0.20 kg-VSS/kg-CODsol. The low-temperature anaerobic treatment was a good option for the pre-treatment of chocolate-processing industry wastewater. PMID:23508162

Esparza-Soto, M; Arzate-Archundia, O; Solís-Morelos, C; Fall, C

2013-01-01

212

Linking bacterial population dynamics and nutrient removal in the granular sludge biofilm ecosystem engineered for wastewater treatment.  

PubMed

Intensive nutrient removal from wastewater in anaerobic-aerobic systems using granular sludge should rely on optimal balances at biofilm and microbial ecology levels. This study targets the impacts of reactor characteristics and fluctuations in operation conditions on nutrient removal and bacterial community structures by means of microbial and numerical ecology methods. The dynamics of both predominant and accompanying populations were investigated with high resolution on temporal and phylogenetic scales in two reactors operated during 5 months with synthetic wastewater. Multivariate analyses highlighted significant correlations from process to microbial scales in the first reactor, whereas nitrification and phosphorus removal might have been affected by oxygen mass transfer limitations with no impact at population level in the second system. The bacterial community continuum of the first reactor was composed of two major antagonistic Accumulibacter-Nitrosomonas-Nitrospira and Competibacter-Cytophaga-Intrasporangiaceae clusters that prevailed under conditions leading to efficient P- (> 95%) and N-removal (> 65%) and altered P- (< 90%) and N-removal (< 60%), respectively. A third cluster independent of performances was dominated by Xanthomonadaceae affiliates that were on average more abundant at 25 °C (31 ± 5%) than at 20 °C (22 ± 4%). Starting from the physiological traits of the numerous phylotypes identified, a conceptual model is proposed as a base for functional analysis in the granular sludge microbiome and for future investigations with complex real wastewater. PMID:24646314

Weissbrodt, David G; Shani, Noam; Holliger, Christof

2014-06-01

213

Consolidation Characteristics of Wastewater Sludge  

Microsoft Academic Search

Capping is a cost-effective remediation method for soft contaminated sludge. The Madison Metropolitan Sewerage District evaluated different remediation alternatives to treat its polychlorinated biphenyl (PCB) contaminated sludge and the U.S. EPA agreed to permit capping as the method of remediation. Design of the cap required knowledge of the consolidation behavior of the sludge. In order to analyze this behavior, a

Ahmet H. Aydilek; Tuncer B. Edil; Patrick J. Fox

214

BIOLOGICAL TREATMENT OF HIGH STRENGTH PETROCHEMICAL WASTEWATER  

EPA Science Inventory

The biological treatment of a complex petrochemical wastewater containing high concentrations of organic chlorides, nitrates, and amines was initially studied using a sequence of anaerobic methanogenesis and oxygen activated sludge. Bench-scale and pilot-plant treatability studie...

215

Restoring a sludge holding tank at a wastewater treatment plant using high-performance coatings  

SciTech Connect

Faced with a serious hydrogen sulfide (H{sub 2}S) corrosion problem in two sludge holding tanks in 1993, the city of Concord, New Hampshire, repaired the deteriorating substrate by using a conventional acrylic-modified cementitious resurfacer and a coal tar epoxy (CTE) coating system. CTE failure occurred within 2 years, leading to more severe coating delamination. Restoration was delayed for 10 years, which caused extensive chemical attack on the concrete substrate-upwards of 2 in. (50 mm) of concrete loss. This article explains how one of these tanks was restored and prepared for another 15+ years of service.

O'Dea, V. [Tnemec Co. Inc., Kansas City, MO (United States)

2005-11-01

216

Harvesting biogas from wastewater sludge and food waste  

NASA Astrophysics Data System (ADS)

Wastewater sludge and food waste are good source of biogas. Anaerobic treatment of slude and food waste able to produce biogas which is a potential renewable energy source. This study looks into the potential biogas generation and the effects of temperature on biogas generation. A lab scale reactor was used to simulate the biogas generation. The results show that wastewater sludge able to produced upto 44.82 ml biogas/kg of sludge. When mixed with food waste at a ratio of 30:70 (food waste), the biogas generated were 219.07 ml/kg of waste. Anaerobic of food waste alone produced biogas amount to 59.75 ml/kg of food waste. Anaerobic treatment also reduces the volume of waste. The effect of temperature shows that higher temperature produces more biogas than lower temperature.

Chua, K. H.; Cheah, W. L.; Tan, C. F.; Leong, Y. P.

2013-06-01

217

Brevibacterium ammoniilyticum sp. nov., an ammonia-degrading bacterium isolated from sludge of a wastewater treatment plant.  

PubMed

A Gram-stain-positive, non-motile, chemo-organotrophic, mesophilic, aerobic bacterium, designated A1(T), was isolated from sludge of a wastewater treatment plant. Strain A1(T) showed good ability to degrade ammonia and grew well on media amended with methanol and ammonia. Strain A1(T) grew with 0-11?% (w/v) NaCl, at 20-42 °C, but not <15 or >45 °C and at pH 6-10 (optimum pH 8.0-9.0). The isolate was catalase-positive and oxidase-negative. The DNA G+C content was 70.7 mol%. A comparative analysis of 16S rRNA gene sequences revealed that strain A1(T) formed a distinct phyletic lineage in the genus Brevibacterium and showed high sequence similarity with Brevibacterium casei NCDO 2048(T) (96.9?%), Brevibacterium celere KMM 3637(T) (96.9?%) and Brevibacterium sanguinis CF63(T) (96.4?%). DNA-DNA hybridization revealed <43?% DNA-DNA relatedness between the isolate and its closest phylogenetic relatives. The affiliation of strain A1(T) with the genus Brevibacterium was supported by the chemotaxonomic data: predominant quinone menaquinone MK-7(H2); polar lipid profile containing diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid; characteristic cell-wall diamino acid meso-diaminopimelic acid; whole-cell sugars galactose, xylose and ribose; absence of mycolic acids; and major fatty acids iso-C15?:?0, anteiso-C15?:?0 and anteiso-C17?:?0. The results of physiological and biochemical tests allowed phenotypic differentiation of strain A1(T) from members of the genus Brevibacterium. On the basis of the results in this study, a novel species, Brevibacterium ammoniilyticum sp. nov., is proposed. The type strain is A1(T) (?=?KEMC 41-098(T) ?=?JCM 17537(T) ?=?KACC 15558(T)). PMID:22729022

Kim, Jinsoo; Srinivasan, Sathiyaraj; You, Taek; Bang, John J; Park, Sujeong; Lee, Sang-Seob

2013-03-01

218

Nocardioides daeguensis sp. nov., a nitrate-reducing bacterium isolated from activated sludge of an industrial wastewater treatment plant.  

PubMed

A Gram-reaction-positive, rod-shaped, non-spore-forming bacterium (strain 2C1-5(T)) was isolated from activated sludge of an industrial wastewater treatment plant in Daegu, South Korea. Its taxonomic position was investigated by using a polyphasic approach. On the basis of 16S rRNA gene sequence similarity, the closest phylogenetic relatives were the type strains of Nocardioides nitrophenolicus (98.6?% similarity), N. kongjuensis (98.5?%), N. caeni (98.4?%), N. simplex (98.3?%), N. aromaticivorans (98.1?%) and N. ginsengisoli (97.5?%); the phylogenetic distance from other species with validly published names within the genus Nocardioides was greater than 3?%. Strain 2C1-5(T) was characterized chemotaxonomically as having ll-2,6-diaminopimelic acid in the cell-wall peptidoglycan, MK-8(H4) as the predominant menaquinone and iso-C16?:?0, C16?:?0 and C17?:?1?6c as the major fatty acids. The G+C content of the genomic DNA was 74.9 mol%. These chemotaxonomic properties and phenotypic characteristics supported the affiliation of strain 2C1-5(T) to the genus Nocardioides. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain 2C1-5(T) from existing species with validly published names. Therefore, strain 2C1-5(T) represents a novel species of the genus Nocardioides, for which the name Nocardioides daeguensis sp. nov. is proposed, with the type strain 2C1-5(T) (?=?JCM 17460(T)?=?KCTC 19799(T)). PMID:23645020

Cui, Yingshun; Woo, Sung-Geun; Lee, Jangho; Sinha, Sahastranshu; Kang, Myung-Suk; Jin, Long; Kim, Kwang Kyu; Park, Joonhong; Lee, Myungjin; Lee, Sung-Taik

2013-10-01

219

Anaerobic biological treatment of alginate production wastewaters in a pilot-scale expended granular sludge bed reactor under moderate to low temperatures.  

PubMed

Psychrophilic anaerobic digestion recently has been demonstrated as a cost-effective option for the treatment of a range of wastewater categories. In this study, the treatment of alginate production wastewaters was carried out in a pilot-scale expended granular sludge bed (EGSB) reactor. After a 40-day startup with two inocula, a 163-day experiment was run, from moderate to low temperatures, to treat seaweed-based-production wastewater. The results showed that inoculating with the active granular sludge instead of flocculent biomass can remarkably speed up the startup, and, at applied organic loading rates of 1.5 to 3.0 kg chemical oxygen demand (COD)/m3 x d, COD removal efficiencies of 55.4 to 72.6% were achieved. The volatile suspended solids ratio decreased slowly with operation time, as a result of the extremely slow growth rates of microorganisms and the accumulation of inorganic substances. Morphological examination and particle-size distribution of the granules revealed their tendency to disintegrate. Inorganic precipitates, microorganism shift, and substrate limitations may have contributed to it. PMID:20853751

Li, Gaojie; Zhang, Zhenjia

2010-08-01

220

Wastewater Treatment  

NSDL National Science Digital Library

From the USGS Water Science for School's comes this information on what wastewater is and why it is treated, by looking at the potential ways it can affect fisheries, wildlife habitats, recreational sites, and human health concerns.

2008-04-24

221

Changes of microbial characteristics of retained sludge during low-temperature operation of an EGSB reactor for low-strength wastewater treatment.  

PubMed

In this study, a lab scale EGSB reactor was operated for 400 days to investigate the influence of temperature-decrease on the microbial characteristic of retained sludge. The EGSB reactor was started-up at 15 degrees C seeding with 20 degrees C-grown granular sludge. The influent COD of synthetic wastewater was set at 0.6-0.8 gCOD/L. The process-temperature was stepwise reduced from 15 degrees C to 5 degrees C during 400 days operation. Decrease of temperature of the reactor from 15 degrees C to 10 degrees C caused the decline of COD removal efficiency. However, continuous operation of the EGSB reactor led the efficient treatment of wastewater (70% of COD removal, 50% of methane recovery) at 10 degrees C. We confirmed that the both acetate-fed and hydrogen-fed methanogenic activities of retained sludge clearly increased under 15 to 20 degrees C. Changes of microbial profiles of methanogenic bacteria were analyzed by 16S rDNA-targeted DGGE analysis and cloning. It shows that genus Methanospirillum as hydrogen-utilizing methanogen proliferated due to low temperature operation of the reactor. On the other hand, genus Methanosaeta presented in abundance as acetoclastic-methanogen throughout the experiment. PMID:18235183

Syutsubo, K; Yoochatchaval, W; Yoshida, H; Nishiyama, K; Okawara, M; Sumino, H; Araki, N; Harada, H; Ohashi, A

2008-01-01

222

Wastewater Treatment Plant Sites Acquisition Study. Panama Bay Sanitation Project.  

National Technical Information Service (NTIS)

Hazen and Sawyer were retained by the CU to conduct the Conceptual Design which consisted of four complementary studies as follows: (1) Wastewater Flow Monitoring and Sampling Study; (2) Wastewater Treatment Plant Sites Acquisition Study; (3) Sludge Manag...

2003-01-01

223

Removal of dissolved Zn(II) using coal mine drainage sludge: implications for acidic wastewater treatment.  

PubMed

The mechanism for the removal of Zn(II) by using coal mine drainage sludge (CMDS) was investigated by spectroscopic analysis and observations of batch tests using model materials. Zeta potential analysis showed that CMDS(25) (dried at 25 °C) and CMDS(550) (dried at 550 °C) had a much lower isoelectric point of pH (pH(IEP)) than either goethite or calcite, which are the main constituents of CMDS. This indicates that the negatively charged anion (sulfate) was incorporated into the structural networks and adsorbed on the surface of CMDS via outer-sphere complexation. The removal of Zn(II) by CMDS was thought to be primarily caused by sulfate-complexed iron (oxy)hydroxide and calcite. In particular, the electrostatic attraction of the negatively charged functional group, FeOH-SO(4)(2-), to the dissolved Zn(II) could provide high removal efficiencies over a wide pH range. Thermodynamic modeling and Fourier transform infrared spectroscopy (FT-IR) demonstrated that ZnSO(4) is the dominant species in the pH range 3-7 as the sulfate complexes with the hydroxyl groups, whereas the precipitation of Zn(II) as ZnCO(3) or Zn(5)(CO(3))(2) (OH)(6) through the dissolution of calcite is the dominant mechanism in the pH range 7-9.6. PMID:23295677

Cui, Mingcan; Jang, Min; Cannon, Fred S; Na, Seunmin; Khim, Jeehyeong; Park, Jae Kwang

2013-02-15

224

Biodegradability of wastewater and activated sludge organics in anaerobic digestion.  

PubMed

The investigation provides experimental evidence that the unbiodegradable particulate organics fractions of primary sludge and waste activated sludge calculated from activated sludge models remain essentially unbiodegradable in anaerobic digestion. This was tested by feeding the waste activated sludge (WAS) from three different laboratory activated sludge (AS) systems to three separate anaerobic digesters (AD). Two of the AS systems were Modified Ludzack - Ettinger (MLE) nitrification-denitrification (ND) systems and the third was a membrane University of Cape Town (UCT) ND and enhanced biological P removal system. One of the MLE systems and the UCT system were fed the same real settled wastewater. The other MLE system was fed raw wastewater which was made by adding a measured constant flux (gCOD/d) of macerated primary sludge (PS) to the real settled wastewater. This PS was also fed to a fourth AD and a blend of PS and WAS from settled wastewater MLE system was fed to a fifth AD. The five ADs were each operated at five different sludge ages (10-60d). From the measured performance results of the AS systems, the unbiodegradable particulate organic (UPO) COD fractions of the raw and settled wastewaters, the PS and the WAS from the three AS systems were calculated with AS models. These AS model based UPO fractions of the PS and WAS were compared with the UPO fractions calculated from the performance results of the ADs fed these sludges. For the PS, the UPO fraction calculated from the AS and AD models matched closely, i.e. 0.30 and 0.31. Provided the UPO of heterotrophic (OHO, fE_OHO) and phosphorus accumulating (PAO, fE_PAO) biomass were accepted to be those associated with the death regeneration model of organism "decay", the UPO of the WAS calculated from the AS and AD models also matched well - if the steady state AS model fE_OHO = 0.20 and fE_PAO = 0.25 values were used, then the UPO fraction of the WAS calculated from the AS models deviated significantly from those calculated with the AD models. Therefore in plant wide wastewater treatment models the characterization of PS and WAS as defined by the AS models can be applied without modification in AD models. The observed rate limiting hydrolysis/acidogenesis rates of the sludges are listed. PMID:24699419

Ikumi, D S; Harding, T H; Ekama, G A

2014-06-01

225

Removal of phosphorus from agricultural wastewaters using adsorption media prepared from acid mine drainage sludge  

Microsoft Academic Search

Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid mine drainage sludge is a waste product produced by the neutralization of acid mine drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the

Philip L. Sibrell; Gary A. Montgomery; Kelsey L. Ritenour; Travis W. Tucker

2009-01-01

226

Influence of pyrolysis temperature on production and nutrient properties of wastewater sludge biochar.  

PubMed

The important challenge for effective management of wastewater sludge materials in an environmentally and economically acceptable way can be addressed through pyrolytic conversion of the sludge to biochar and agricultural applications of the biochar. The aim of this work is to investigate the influence of pyrolysis temperature on production of wastewater sludge biochar and evaluate the properties required for agronomic applications. Wastewater sludge collected from an urban wastewater treatment plant was pyrolysed in a laboratory scale reactor. It was found that by increasing the pyrolysis temperature (over the range from 300 °C to 700 °C) the yield of biochar decreased. Biochar produced at low temperature was acidic whereas at high temperature it was alkaline in nature. The concentration of nitrogen was found to decrease while micronutrients increased with increasing temperature. Concentrations of trace metals present in wastewater sludge varied with temperature and were found to primarily enriched in the biochar. PMID:20870338

Hossain, Mustafa K; Strezov, Vladimir; Chan, K Yin; Ziolkowski, Artur; Nelson, Peter F

2011-01-01

227

FEASIBILITY STUDY OF OPEN TANK OXYGEN-ACTIVATED SLUDGE WASTEWATER TREATMENT  

EPA Science Inventory

The pilot plant for this study consisted of one oxygenation basin and two clarifiers. The system treated primary clarifier effluent from the Englewood, Colorado, treatment facility. The influent flow rate was adjusted to attain average aeration reactor detention times ranging fro...

228

Electricity generation using chocolate industry wastewater and its treatment in activated sludge based microbial fuel cell and analysis of developed microbial community in the anode chamber.  

PubMed

Feasibility of using chocolate industry wastewater as a substrate for electricity generation using activated sludge as a source of microorganisms was investigated in two-chambered microbial fuel cell. The maximum current generated with membrane and salt bridge MFCs was 3.02 and 2.3 A/m(2), respectively, at 100 ohms external resistance, whereas the maximum current generated in glucose powered MFC was 3.1 A/m(2). The use of chocolate industry wastewater in cathode chamber was promising with 4.1 mA current output. Significant reduction in COD, BOD, total solids and total dissolved solids of wastewater by 75%, 65%, 68%, 50%, respectively, indicated effective wastewater treatment in batch experiments. The 16S rDNA analysis of anode biofilm and suspended cells revealed predominance of beta-Proteobacteria clones with 50.6% followed by unclassified bacteria (9.9%), alpha-Proteobacteria (9.1%), other Proteobacteria (9%), Planctomycetes (5.8%), Firmicutes (4.9%), Nitrospora (3.3%), Spirochaetes (3.3%), Bacteroides (2.4%) and gamma-Proteobacteria (0.8%). Diverse bacterial groups represented as members of the anode chamber community. PMID:19539465

Patil, Sunil A; Surakasi, Venkata Prasad; Koul, Sandeep; Ijmulwar, Shrikant; Vivek, Amar; Shouche, Y S; Kapadnis, B P

2009-11-01

229

Combined anaerobic and activated sludge anoxic\\/oxic treatment for piggery wastewater  

Microsoft Academic Search

A process combining anaerobic digestion and anoxic\\/oxic treatment was developed to treat pig slurry in-order-to partially convert organic matter (OM) into a valuable energy and simultaneously to comply with the environmental constraints as regards to nitrogen removal. However, OM content of digested pig slurry is insufficient to allow a further complete denitrification of the mineral nitrogen content. Hence, four different

Rajinikanth Rajagopal; Pierre Rousseau; Nicolas Bernet; Fabrice Béline

2011-01-01

230

Treatment of winery effluent with upflow anaerobic sludge blanket (UASB) – granular sludges enriched with Enterobacter sakazakii  

Microsoft Academic Search

Three upflow anaerobic sludge blankets (UASBs) were evaluated for the treatment of winery wastewater: the first was seeded with granular sludge enriched with Enterobacter sakazakii and reached a 90% COD removal within 17 d at hydraulic retention time of 24 h; the second was seeded with brewery granules and achieved 85% COD removal within 50 d, the third was seeded with just sludge

M. Keyser; R. C. Witthuhn; L.-C. Ronquest; T. J. Britz

2003-01-01

231

FULL SCALE DEMONSTRATION AND ASSESSMENT OF ENZYMIC HYDROLYSIS PRETREATMENT FOR MESOPHILIC ANAEROBIC DIGESTION OF MUNICIPAL WASTEWATER TREATMENT SLUDGE  

Microsoft Academic Search

A full-scale monitoring programme was undertaken to assess acidogenic pre-treatment as a bolt- on biological upgrade to mesophilic anaerobic digestion (MAD). The United Utilities Enhanced Enzymic Hydrolysis (EEH) MAD pre-treatment process was installed by Monsal Limited at the Blackburn (UK) wastewater treatment plant. This process combines mesophilic acid phase digestion with pasteurization at 55 ºC using low grade boiler heat

Alan G. Werker; My Carlsson; Fernando Morgan-Sagastume; Dorian Harrison

232

High-nitrate wastewater treatment in an expanded granular sludge bed reactor and microbial diversity using 454 pyrosequencing analysis.  

PubMed

Denitrification of high concentration of nitrate wastewater was investigated in expanded granular sludge bed (EGSB) reactor with sodium acetate as the carbon source. The optimal parameters were achieved with C/N mole ratio of 2.0, liquid up-flow velocity (Vup) of 3.0 m/h and pH of 6.2-8.2. Complete denitrification can be achieved even with nitrate nitrogen concentration as high as 14000 mg/L. Furthermore, 454-pyrosequencing technology was used to analyze bacterial diversity. Results showed that a total of 5573 sequences were obtained which could be affiliated to 6 phylogenetic groups, including Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, Chloroflexi and unclassified phylum. Proteobacteria (84.53%) was the dominant microbial population, followed by Firmicutes (13.24%) and Actinobacteria (0.38%). The dominate phylum was different from that in other anaerobic system. PMID:23500551

Liao, Runhua; Shen, Ke; Li, Ai-Min; Shi, Peng; Li, Yan; Shi, Qianqian; Wang, Zhu

2013-04-01

233

Combined anaerobic and activated sludge anoxic/oxic treatment for piggery wastewater.  

PubMed

A process combining anaerobic digestion and anoxic/oxic treatment was developed to treat pig slurry in-order-to partially convert organic matter (OM) into a valuable energy and simultaneously to comply with the environmental constraints as regards to nitrogen removal. However, OM content of digested pig slurry is insufficient to allow a further complete denitrification of the mineral nitrogen content. Hence, four different configurations were designed and evaluated to manage the OM requirements and achieve denitrification. Partial nitrification (PN) of ammonium to nitrite was also applied by regulating oxygen inflow time. Thus, the combined process could remove 38-52% of CODt, 79-88% of CODs, 66-75% of TN and 98-99% of NH(4)(+)N concentrations depending on the slurry characteristics. Anaerobic digestion was able to produce 5.9 Nm(3) of CH(4)/m(slurry added)(3). PN allowed a reduction in the oxygen and OM requirements respectively for nitrification and denitrification. Thus, this process trims-down the energy costs at the farm scale. PMID:21050751

Rajagopal, Rajinikanth; Rousseau, Pierre; Bernet, Nicolas; Béline, Fabrice

2011-02-01

234

Wastewater and sludge control-technology options for synfuels industries. Volume 2: tar-sand-combustion process water-removal of organic constituents by activated-sludge treatment  

SciTech Connect

Gas-chromatography/mass-spectrometry analysis of raw process water from reverse-forward combustion in a tar sand extraction experiment indicated that identifiable compounds were distributed in about equal portions among acid, base, and neutral fractions. The compounds in the neutral fraction were unsaturated, oxygenated methyl cyclohexenyl ketones, methyl-methylcyclohexenyl ketones, acetophenones including methyl-tolyl ketones, lactones, and indanones. Neutral fraction constituents were reduced by about 99% during activated-sludge treatment. The base fraction consisted pyridines, quinolines and their alkane substitutes, and acridines. These compounds were reduced by about 76% during treatment. The acid fraction consisted of carboxylic acids ranging in molecular weight from C/sub 1/ to C/sub 11/, phenols and cresols, and benzoic and toluic acids. These materials were reduced by about 95% through activated-sludge treatment. It was concluded that (1) activated-sludge treatment can reduce soluble organic carbon and chemical oxygen demand by about 90% in the process water and (2) the water is nonmutagenic as defined by the standard Salmonella/Ames test.

Torpy, M.F.; Raphaelian, L.A.; Luthy, R.G.

1981-11-01

235

Integration of anammox into the aerobic granular sludge process for main stream wastewater treatment at ambient temperatures.  

PubMed

Anaerobic ammonium oxidation, nitrification and removal of COD was studied at ambient temperature (18 °C ± 3) in an anoxic/aerobic granular sludge reactor during 390 days. The reactor was operated in a sequencing fed batch mode and was fed with acetate and ammonium containing medium with a COD/N ratio of 0.5 [g COD/gN]. During influent addition, the medium was mixed with recycled effluent which contained nitrate in order to allow acetate oxidation and nitrate reduction by anammox bacteria. In the remainder of the operational cycle the reactor was aerated and controlled at a dissolved oxygen concentration of 1.5 mg O(2)/l in order to establish simultaneous nitritation and Anammox. Fluorescent in-situ hybridization (FISH) revealed that the dominant Anammox bacterial population shifted toward Candidatus "Brocadia fulgida" which is known to be capable of organotrophic nitrate reduction. The reactor achieved stable volumetric removal rates of 900 [g N(2)-N/m(3)/day] and 600 [g COD/m(3)/day]. During the total experimental period Anammox bacteria remained dominant and the sludge production was 5 fold lower than what was expected by heterotrophic growth suggesting that consumed acetate was not used by heterotrophs. These observations show that Anammox bacteria can effectively compete for COD at ambient temperatures and can remove effectively nitrate with a limited amount of acetate. This study indicates a potential successful route toward application of Anammox in granular sludge reactors on municipal wastewater with a limited amount of COD. PMID:22094002

Winkler, M-K H; Kleerebezem, R; van Loosdrecht, M C M

2012-01-01

236

The Sources and Behavior of Heavy Metals in Wastewater and Sludges.  

National Technical Information Service (NTIS)

A critical evaluation has been made of the literature regarding the sources of heavy metals in sludges from municipal wastewater treatment plants. Residential loadings of heavy metals as a percentage of total metal loads are highly variable with respect t...

B. W. Vigon R. A. Craig N. A. Frazier

1977-01-01

237

Anaerobic digestion and wastewater treatment systems  

Microsoft Academic Search

Upflow Anaerobic Sludge Bed (UASB) wastewater (pre-)treatment systems represent a proven sustainable technology for a wide range of very different industrial effluents, including those containing toxic\\/inhibitory compounds. The process is also feasible for treatment of domestic wastewater with temperatures as low as 14–16° C and likely even lower. Compared to conventional aerobic treatment systems the anaerobic treatment process merely offers

G. Lettinga

1995-01-01

238

Carbonate addition - an effective remedy against poor activated sludge settling properties and alkalinity conditions in small wastewater treatment plants  

Microsoft Academic Search

The impact of marble powder on the performance of small seasonal treatment plants dealing with high ammonia concentrated wastewater has been investigated. The carbonate has been added to one of two parallel lab-scale SBR-systems as an alkalinity depot and a bio-carrier. The focus of the monitoring program was put on the measurement of carbon fractions in the liquid and the

B. Wett; A. Eladawy; W. Becker

239

Sludge Generation from Ferrous/Sulfide Chromium Treatment.  

National Technical Information Service (NTIS)

The reaction pH and reduction chemical can drastically effect the volume of wastewater treatment sludges produced in chromium treatment. Experiments at the Air Force Engineering and Services Laboratory have shown that mixing sodium sulfide and ferrous chl...

J. R. Aldrich

1984-01-01

240

Treatment of domestic wastewater in an up-flow anaerobic sludge blanket reactor followed by moving bed biofilm reactor  

Microsoft Academic Search

The performance of a laboratory-scale sewage treatment system composed of an up-flow anaerobic sludge blanket (UASB) reactor\\u000a and a moving bed biofilm reactor (MBBR) at a temperature of (22–35 °C) was evaluated. The entire treatment system was operated\\u000a at different hydraulic retention times (HRT’s) of 13.3, 10 and 5.0 h. An overall reduction of 80–86% for CODtotal; 51–73% for CODcolloidal and 20–55%

A. Tawfik; F. El-Gohary; H. Temmink

2010-01-01

241

Increased biogas production at wastewater treatment plants through co-digestion of sewage sludge with grease trap sludge from a meat processing plant  

Microsoft Academic Search

The feasibility of co-digesting grease trap sludge from a meat-processing plant and sewage sludge was studied in batch and reactor experiments at 35°C. Grease trap sludge had high methane production potential (918m3\\/tVSadded), but methane production started slowly. When mixed with sewage sludge, methane production started immediately and the potential increased with increasing grease trap sludge content. Semi-continuous co-digestion of the

S. Luostarinen; S. Luste; M. Sillanpää

2009-01-01

242

Study of Salt Wash Water Toxicity on Wastewater Treatment  

Microsoft Academic Search

This research effort focused on evaluating the toxicity of the saline waste water generated from washing of Indiana Department of Transportation (INDOT) deicing trucks and to study the feasibility of discharging it into wastewater treatment plants. Performance of activated sludge treating wastewater under varying levels of salt concentration was studied by measuring the Chemical Oxygen Demand (COD), activated sludge oxygen

Mostafa F. Hashad; Surabhi Sharma; Loring F. Nies; James E. Alleman

2006-01-01

243

Effects of sludge retention time and biosurfactant on the treatment of polyaromatic hydrocarbon (PAH) in a petrochemical industry wastewater.  

PubMed

A laboratory-scale aerobic activated sludge reactor (AASR) system was employed to investigate the effects of sludge retention time (SRT) on the removal of three polyaromatic hydrocarbons (PAHs) with low benzene rings [(acenaphthene (ACT), fluorene (FLN) and phenanthrene (PHE)] and six PAHs with high benzene rings [(benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene (DahA), benzo[g,h,i]perylene (BghiP)] in the presence of rhamnolipid (RD), emulsan (EM) and surfactine (SR) biosurfactants. This study showed that biosurfactants enhance the PAH biodegradation by increasing the biomass growth. RD exhibits a better performance than the other biosurfactants in the removal of the chemical oxygen demand (COD) and PAHs. At a RD concentration of 15 mg/L aerobic treatment for 25 days, SRT was enough to remove over 95% of total PAHs, and COD(dis). Under the same conditions 75% of COD originating from the inert organics (COD(inert)) and 96% of COD originating from the inert soluble microbial products (COD(imp)) were removed. At 25 days SRT and 15 mg/L RD concentration, about 88% of PAHs were biodegraded by the AASR system, 4% were accumulated in the system, 3% were released in the effluent, and 5% remained in the waste sludge. PMID:22156134

Sponza, D T; Gok, O

2011-01-01

244

Cometabolic degradation of organic wastewater micropollutants by activated sludge and sludge-inherent microorganisms.  

PubMed

Municipal wastewaters contain a multitude of organic trace pollutants. Often, their biodegradability by activated sludge microorganisms is decisive for their elimination during wastewater treatment. Since the amounts of micropollutants seem too low to serve as growth substrate, cometabolism is supposed to be the dominating biodegradation process. Nevertheless, as many biodegradation studies were performed without the intention to discriminate between metabolic and cometabolic processes, the specific contribution of the latter to substance transformations is often not clarified. This minireview summarizes current knowledge about the cometabolic degradation of organic trace pollutants by activated sludge and sludge-inherent microorganisms. Due to their relevance for communal wastewater contamination, the focus is laid on pharmaceuticals, personal care products, antibiotics, estrogens, and nonylphenols. Wherever possible, reference is made to the molecular process level, i.e., cometabolic pathways, involved enzymes, and formed transformation products. Particular cometabolic capabilities of different activated sludge consortia and various microbial species are highlighted. Process conditions favoring cometabolic activities are emphasized. Finally, knowledge gaps are identified, and research perspectives are outlined. PMID:24866947

Fischer, Klaus; Majewsky, Marius

2014-08-01

245

The challenge of analyzing beta-blocker drugs in sludge and wastewater  

Microsoft Academic Search

In this study, different approaches were used to assess and overcome the severe effects of interference from the sample matrix\\u000a from different types of sludges and wastewater on the analysis of nine beta-blockers and the beta sympathomimetic clenbuterol.\\u000a The partitioning of the target compounds into sludge was investigated in wastewater treatment plants (WWTPs) in both Canada\\u000a and Germany to evaluate

Marco Scheurer; Maria Ramil; Chris D. Metcalfe; Stefanie Groh; Thomas A. Ternes

2010-01-01

246

Treatment of poultry slaughterhouse wastewater in hybrid upflow anaerobic sludge blanket reactor packed with pleated poly vinyl chloride rings.  

PubMed

In this study, the performance of 5.4 L hybrid upflow anaerobic sludge blanket (HUASB) reactor for treating poultry slaughterhouse wastewater under mesophilic conditions (29-35 °C), was investigated. After starting-up, the reactor was loaded up to an OLR of 19 kg COD/m3 d and achieved varied TCOD and SCOD removal efficiencies of 70-86% and 80-92%, respectively. The biogas was varied between 1.1 and 5.2 m3/m3 d with the maximum methane content of 72%. The maximum methane yield was 0.32 m3/kg CODremoved at an OLR of 9.27 kg COD/m3 d. Black matured granules of size between 2.5 and 5 mm were observed at the end of 225 d operation. RTD study showed the flow behavior was in mixed regime at the end of performance study. Step wise polynomial regression analysis was fitted well. Methanobacterium and Methanosaeta bacteria were dominant at the end of start-up whereas Methanosarcina, Cocci and rods were predominant at the end of performance studies. PMID:22055104

Rajakumar, R; Meenambal, T; Saravanan, P M; Ananthanarayanan, P

2012-01-01

247

Treatment of oilfield wastewater containing polymer by the batch activated sludge reactor combined with a zerovalent iron/EDTA/air system.  

PubMed

Laboratory-scale experiments were conducted in order to evaluate the performance of a novel treatment process for oilfield wastewater based on combining chemical oxidation, performed by a zerovalent iron (ZVI), ethylenediamine tetraacetic acid (EDTA) and air process, with biological degradation, carried out in a batch activated sludge reactor. The influence of some operating variables was studied. The results showed that the optimum pretreatment conditions were 150 mg/L EDTA, 20 g/L ZVI, and a 180-min reaction time, respectively. Under these conditions, removal efficiencies for hydrolyzed polyacrylamide (HPAM), total petroleum hydrocarbons (TPH), and chemical oxygen demand (COD) were 66%, 59%, and 45%, respectively. During the subsequent 40 h of bioremediation, the concentrations of HPAM, TPH, and COD were decreased to 10, 2 and 85 mg/L, respectively. At the end of experiments, the total removal efficiencies of HPAM, TPH, and COD were 96%, 97% and 92%, respectively. PMID:21163643

Lu, Mang; Wei, Xiaofang

2011-02-01

248

PARASITES IN SOUTHERN SLUDGES AND DISINFECTION BY STANDARD SLUDGE TREATMENT  

EPA Science Inventory

Major objectives were to: (a) assess types and densities of parasites in municipal wastewater sludges in the southern United States, (b) investigate the inactivation of parasites by lime stabilization of sewage sludges seeded with selected intestinal parasites, (c) assess convent...

249

Psychrophilic anaerobic treatment of low strength wastewaters  

Microsoft Academic Search

The main objective of this thesis was to design a high-rate anaerobic system for the treatment low strength wastewaters under psychrophilic conditions.Psychrophilic (3 to 20 °C) anaerobic treatment of low strength synthetic and malting wastewater was investigated using a single and two stage expanded granular sludge bed (EGSB) reactor system. The chemical oxygen demand (COD) removal efficiencies found in the experiments

S. Rebac; Lier van J. B; P. Lens; A. J. M. Stams; F. Dekkers; K. T. M. Swinkels; G. Lettinga

1998-01-01

250

Quantification of pathogenic micro-organisms in the sludge from treated hospital wastewater.  

PubMed

The sludge from hospital waste treatment facilities is a potential source of infectious organisms. The average numbers of micro-organisms in the sludge of hospital wastewater in Taiwan were as follows: total count 8.1 x 10(7) cfu g-1 (dry weight of sludge), and 1.4 x 10(6), 3.6 x 10(5), 1.6 x 10(5), 2.2 x 10(5) and 5.5 x 10(4) cfu g-1 (dry weight of sludge) for total coliforms, faecal coliforms, faecal streptococci, Pseudomonas aeruginosa and Salmonella spp., respectively. Salmonella spp. were detected in 37% (10 of 27) of the sludges from hospital wastewaters. Therefore, the treatment of such sludge to reduce pathogenic micro-organisms should be considered. PMID:9721667

Tsai, C T; Lai, J S; Lin, S T

1998-07-01

251

The Role of Diatomite Particles in the Activated Sludge System for Treating Coal Gasification Wastewater  

Microsoft Academic Search

Diatomite is a kind of natural low-cost mineral material. It has a number of unique physical properties and has been widely used as an adsorbent in wastewater treatment. This study was conducted to investigate the aerobic biodegradation of coal gasification wastewater with and without diatomite addition. Experimental resultsindicated that diatomite added in the activated sludge system could promote the biomass

Wenqi ZHANG; Pinhua RAO; Hui ZHANG; Jingli XU

2009-01-01

252

Cultivation and characterization of bacterial isolates capable of degrading pharmaceutical and personal care products for improved removal in activated sludge wastewater treatment.  

PubMed

Pharmaceutical and personal care products (PPCPs) discharged with wastewater treatment plant (WWTP) effluents are an emerging surface water quality concern. Biological transformation has been identified as an important removal mechanism during wastewater treatment. The aim of this research was the identification of bacteria with characteristics for potential bioaugmentation to enhance PPCP removal. We report here the cultivation and characterization of bacteria capable of degrading PPCPs to ng/L concentrations. An isolation approach was developed using serial enrichment in mineral medium containing 1 mg/L of an individual PPCP as the sole organic carbon source available to heterotrophs until the original activated sludge inocula was diluted to ~10(-8) of its initial concentration, followed by colony growth on solid R2A agar. Eleven bacteria were isolated, eight that could remove triclosan, bisphenol A, ibuprofen, or 17?-estradiol to below 10 ng/L, one that could remove gemfibrozil to below 60 ng/L, and two that could remove triclosan or E2, but not to ng/L concentrations. Most bacterial isolates degraded contaminants during early growth when grown utilizing rich carbon sources and were only able to degrade the PPCPs on which they were isolated. Seven of the bacterial isolates were sphingomonads, including all the triclosan and bisphenol A degraders and the ibuprofen degrader. The study results indicate that the isolated bacteria may have a positive influence on removal in WWTPs if present at sufficient concentrations and may be useful for bioaugmentation. PMID:23455956

Zhou, Nicolette A; Lutovsky, April C; Andaker, Greta L; Gough, Heidi L; Ferguson, John F

2013-11-01

253

Reuse of treated wastewater and sewage sludge for fertilization and irrigation.  

PubMed

The objective of the present work was to assess the short-term potential of treated wastewater and sewage sludge for ornamental lawn fertilization and irrigation. A field experiment was performed and the following treatments were considered: sewage sludge application + irrigation with public water; sewage sludge application + irrigation with treated wastewater; irrigation with public water; irrigation with treated wastewater (TW). Irrigation with treated wastewater showed a positive effect on lawn installation through higher growth of grass (1,667 cm) and higher dry matter yield (18,147 g m(-2)). These results represent a significant increase in the grass yield compared with public water irrigation. The grass height (2,606 cm) and dry matter yield (23,177 g m(-2)) increased even more, when sewage sludge produced in the wastewater treatment plant (WWTP) was applied to soil, which proves once more its benefits as an organic fertilizer. At the end of the experiment, an increase of some soil parameters (pH, electrical conductivity, organic matter, Ca2+, Na+, K+, Mg2+ and NH4+) was observed, indicating that treated wastewater irrigation can cause a soil sodization. This short-term study indicated that use of treated wastewater and sewage sludge for ornamental lawn fertilization and irrigation is an environmentally sustainable option for re-use of the WWTP by-products. PMID:22097073

Sousa, Gonçalo; Fangueiro, David; Duarte, Elizabeth; Vasconcelos, Ernesto

2011-01-01

254

Alternatives for energy production in aerobic wastewater treatment facilities.  

PubMed

Using technologies such as anaerobic digestion for energy generation from wastewater demands a change in infrastructure that several treatment works are not prepared to immediately implement. This works explores the use of energy production technologies to increase the sustainability of conventional aerobic wastewater treatment plants. The first option considered sludge (a by-product from wastewater treatment) as raw material for biodiesel production as Fatty Acid Methyl Esters (FAME). The second option consisted of the addition of microalgae during aerobic wastewater treatment and subsequent harvesting of combined microalgae-sludge to produce biodiesel. Results showed that microalgae were able to grow in aerobic wastewater treatment reactors, reaching maximum growth after 6 days. The use of microalgae did not statistically affect chemical oxygen demand removal but provided benefits on ammonia removal (100% removal vs 68 ± 9% when microalgae were not added). Activated sludge contained fewer lipids (13 ± 3%, by dry weight) than the microalgae-sludge mixture (20.8 ± 4.5%). Hence, FAME production when using microalgae-sludge was higher (51.12 ± 12 mg of FAME/g of dry microalgae-sludge) than when using activated sludge (25.6 ± 7 mg of FAME/g of dry activated sludge). This work showed that producing biodiesel from microalgae grown in conjunction with bacteria during aerobic wastewater treatment can reduce energy use and carbon emissions produced by 18.6 and 26.5%, respectively. PMID:23787329

Velasquez-Orta, Sharon B

2013-01-01

255

Microbial community structure and population dynamics of granules developed in expanded granular sludge bed (EGSB) reactors for the anaerobic treatment of low-strength wastewater at low temperature.  

PubMed

The anaerobic biological treatment of sucrose-based, low-strength wastewater was investigated in expanded granular sludge bed (EGSB) reactors at low temperatures over a 300-day trial period. During the trial, the operating temperature was lowered in a stepwise manner from 20 degrees C to 5 degrees C. As a result, the reactors exhibited sufficient performances until 10 degrees C operation. The COD removal rate was 3.1-3.8 kgCOD m(-3) day(-1) at 10 degrees C. In particular, the COD removal rate increased gradually through the low-temperature operation; indeed, the later stages of the 10 degrees C operation attained a rate similar to those achieved at 20 degrees C and 15 degrees C. This finding is especially practical for applications of psychrophilic methane fermentation. Additionally, the structure of the microbial community in the granular sludge was analyzed by clone analysis based on 16S rRNA genes and fluorescence in situ hybridization (FISH). As a result, the percentage of the phylum Firmicutes, which were assumed to be Anaerobivrio sp. and Lactococcus sp., greatly increased from 0.7% to 8.0% of the total cells, especially in the surface layer of the granular sludge. These bacteria would contribute to the degradation of the sucrose substrate anaerobically at ambient temperatures. Moreover, the results suggest that a Methanospirillum species, which is a H2-utilizing methanogen, increased from 0.5% to 6.7% during the low-temperature incubation, with a significant increase of methanogenic activity from H2/CO2 at 20 degrees C. Thus, the Methanospirillum species detected in this study may have a key role as hydrogen scavenger during hydrogen-metabolism in low-temperature conditions. PMID:20390923

Tsushima, Ikuo; Yoochatchaval, Wilasinee; Yoshida, Hiroki; Araki, Nobuo; Syutsubo, Kazuaki

2010-01-01

256

UPGRADING FOUNDRY WASTEWATER TREATMENT  

EPA Science Inventory

The paper summarizes findings of a 10-week pilot plant study of gray iron foundry wastewater treatment. Treatment technologies studied included lime softening, lime/soda ash softening, polymer addition, flocculation/sedimentation, and dual media filtration. Results indicate that ...

257

Upgrading Foundry Wastewater Treatment.  

National Technical Information Service (NTIS)

The paper summarizes findings of a 10-week pilot plant study of gray iron foundry wastewater treatment. Treatment technologies studied included lime softening, lime/soda ash softening, polymer addition, flocculation/sedimentation, and dual media filtratio...

R. Osantowski J. S. Ruppersberger

1984-01-01

258

Alaska Wastewater Treatment Technology.  

National Technical Information Service (NTIS)

An assessment has been made of wastewater treatment technology in Alaska. Some of the larger municipalities such as Juneau and Fairbanks have biological treatment plants that are meeting secondary standards. By the middle of 1976, the pipeline camps and p...

R. A. Johnson

1978-01-01

259

Municipal wastewater sludge dewaterability and the presence of microbial extracellular polymer.  

PubMed

Dewatering of sewage sludge is an essential and costly part of the wastewater treatment process. The presence of microbial extracellular polymer (ECP) is important for sludge flocculation, but ECP has also been shown to have a detrimental effect on the dewaterability of certain sludge types. This paper investigates the relationship between sludge dewaterability and the level of ECP present in a range of sludges obtained from 8 full-scale municipal treatment works in the UK. Sludge dewaterability was determined using the capillary suction time (CST) test, and a thermal extraction process followed by solvent precipitation was used for ECP extraction. The results indicate that for each type of sludge examined there appears to be an optimum level of ECP (raw sludge 20 mg ECP/g SS; activated sludge 35 mg ECP/g SS; digested sludge 10 mg ECP/g SS) at which the sludge should exhibit maximum dewaterability. The establishment of a trend between sludge dewaterability and the quantity of ECP present opens up the possibility of manipulating the level of microbial polymer present to aid sludge dewatering, and hence reduce plant operating costs. PMID:11548008

Houghton, J I; Quarmby, J; Stephenson, T

2001-01-01

260

Factors affecting the removal of metals during activated sludge wastewater treatment II. The role of mixed liquor biomass  

Microsoft Academic Search

Samples of mixed liquor from a laboratory-scale activated sludge simulation, operated at a range of sludge ages from 3 to 12 days, were treated with formaldehyde in order to obtain a metabolically inactive biomass. The metal removal behavior of this biomass was compared with that of untreated biomass. Only Cu and Ni were found to exhibit a high degree of

P. S. Lawson; R. M. Sterritt; J. N. Lester

1984-01-01

261

Hydrate Process for Waste Water Treatment Plant Sludge Dewatering: Commercialization Assessment.  

National Technical Information Service (NTIS)

More attention is being paid to innovative technologies for sludge dewatering as larger proportions of wastewater treatment plant budgets are going toward the handling, processing, and disposing of sludge. One such process, the clathrate process, has sign...

1985-01-01

262

Filtration properties of activated sludge in municipal MBR wastewater treatment plants are related to microbial community structure.  

PubMed

In the conventional activated sludge process, a number of important parameters determining the efficiency of settling and dewatering are often linked to specific groups of bacteria in the sludge--namely floc size, residual turbidity, shear sensitivity and composition of extracellular polymeric substances (EPS). In membrane bioreactors (MBRs) the nature of solids separation at the membrane has much in common with sludge dewaterability but less is known about the effect of specific microbial groups on the sludge characteristics that affect this process. In this study, six full-scale MBR plants were investigated to identify correlations between sludge filterability, sludge characteristics, and microbial community structure. The microbial community structure was described by quantitative fluorescence in situ hybridization and sludge filterability by a low-pressure filtration method. A strong correlation between the degree of flocculation (ratio between floc size and residual turbidity) and sludge filterability at low pressure was found. A good balance between EPS and cations in the sludge correlated with good flocculation, relatively large sludge flocs, and low amounts of small particles and single cells in the bulk phase (measured as residual turbidity), all leading to a good filterability. Floc properties could also be linked to the microbial community structure. Bacterial species forming strong microcolonies such as Nitrospira and Accumulibacter were present in plants with good flocculation and filtration properties, while few strong microcolonies and many filamentous bacteria in the plants correlated with poor flocculation and filtration problems. In conclusion this study extends the hitherto accepted perception that plant operation affects floc properties which affects fouling. Additionally, plant operation also affects species composition, which affects floc properties and in the end fouling propensity. PMID:24094729

Bugge, Thomas V; Larsen, Poul; Saunders, Aaron M; Kragelund, Caroline; Wybrandt, Lisbeth; Keiding, Kristian; Christensen, Morten L; Nielsen, Per H

2013-11-01

263

METALS REMOVALS AND PARTITIONING IN CONVENTIONAL WASTEWATER TREATMENT PLANTS  

EPA Science Inventory

Metals removal and partitioning to primary and secondary sludge during treatment of domestic wastewater by conventional sewage treatment processes was studied. Raw wastewater entering the Mill Creek Sewage Treatment Plant, Cincinnati, Ohio, was fed to a 0.1 l/s (1.6 gpm) pilot tr...

264

Destruction and formation of PCDD/Fs in a fluidised bed combustor co-incinerating automotive shredder residue with refuse derived fuel and wastewater treatment sludge.  

PubMed

During an eight day trial automotive shredder residue (ASR) was added to the usual waste feed of a Fluidized Bed Combustor (FBC) for waste-to-energy conversion; the input waste mix consisted of 25% ASR, 25% refuse-derived fuel (RDF) and 50% wastewater treatment (WWT) sludge. All inputs and outputs were sampled and the concentration of the 17 PCDD/Fs with TEF-values was determined in order to obtain "PCDD/F fingerprints". The ASR contained approximately 9000 ng PCDD/Fs/kg(DW), six times more than the RDF and 10 times more than the WWT sludge. The fingerprint of ASR and RDF was dominated by HpCDD and OCDD, which accounted for 90% of the total PDDD/F content, whereas the WWT sludge contained relatively more HpCDFs and OCDF (together 70%). The flue gas cleaning residue (FGCR) and fly and boiler ash contained approximately 30,000 and 2500 ng PCDD/Fs/kg(DW), respectively. The fingerprints of these outputs were also dominated by HpCDFs and OCDF. The bottom ash contained only OCDD and OCDF, in total 8 ng PCDD/Fs/kg (DW). From the comparison of the bottom ash fingerprints with the fingerprints of the other output fractions and of the inputs, it could be concluded that the PCDD/Fs in the waste were destroyed and new PCDD/Fs were formed in the post combustion process by de novo synthesis. During the ASR-co-incineration, the PCDD/F congener concentrations in the fly and boiler ash, FGCR and flue gas were 1.25-10 times higher compared to the same output fractions generated during incineration of the usual waste mix (70% RDF and 30% WWT sludge). The concentration of the higher chlorinated PCDD/Fs increased most. As these congeners have the lowest TEF-factors, the total PCDD/F output, expressed in kg TEQ/year, of the FBC did not increase significantly when ASR was co-incinerated. Due to the relatively high copper levels in the ASR, the copper concentrations in the FBCs outputs increased. As copper catalysis the de novo syntheses, this could explain the increase in PCDD/F concentrations in these outputs. PMID:21621915

Van Caneghem, J; Vermeulen, I; Block, C; Van Brecht, A; Van Royen, P; Jaspers, M; Wauters, G; Vandecasteele, C

2012-03-15

265

Pretreatment and Ultimate Disposal of Wastewater Solids.  

National Technical Information Service (NTIS)

Contents: Overview of sludge handling and disposal; Elemental analysis of wastewater sludges from 33 wastewater treatment plants in the United States; Stabilization of municipal sewage sludge by high lime dose; Thermal degradation of sludges; Thickening c...

A. Freiberger

1974-01-01

266

Waste-Water Treatment Plant Control.  

National Technical Information Service (NTIS)

The Carrousel is a waste-water treatment plant based on the functioning of the activated sludge process. in this biochemical process, ammonium and nitrate and/or nitrite are broken down by living biomass. The main contribution to plant operation costs is ...

K. van Schagen R. Banning A. M. J. Veersma

1996-01-01

267

Microbiologically influenced corrosion in wastewater treatment plants  

Microsoft Academic Search

Microbiologically influenced corrosion (MIC) activity in wastewater treatment plans is discussed. Three case histories are presented showing throughwall pitting from MIC in recycle activated sludge process piping systems. Field and laboratory investigation activities are reported. Alternatives are reviewed for corrosion prevention and mitigation.

J. B. Soebbing; R. A. Yolo

1996-01-01

268

Microbiologically influenced corrosion in wastewater treatment plants  

SciTech Connect

Microbiologically influenced corrosion (MIC) activity in wastewater treatment plans is discussed. Three case histories are presented showing throughwall pitting from MIC in recycle activated sludge process piping systems. Field and laboratory investigation activities are reported. Alternatives are reviewed for corrosion prevention and mitigation.

Soebbing, J.B. [CH2M Hill, Greenwood Village, CO (United States); Yolo, R.A. [CH2M Hill, Milwaukee, WI (United States)

1996-09-01

269

HEALTH EFFECTS OF A WASTEWATER TREATMENT SYSTEM  

EPA Science Inventory

Data obtained as part of a comprehensive community health study conducted during 1965-1971 were utilized to examine the incidence of acute illness in a population surrounding an activated sludge wastewater treatment plant and a control location in Tecumseh, Michigan. Study partic...

270

MATERIALS FOR OXYGENATED WASTEWATER TREATMENT PLANT CONSTRUCTION  

EPA Science Inventory

This research study was initiated to identify resistant materials for construction of wastewater treatment plants using the oxygen activated sludge process. In this investigation, samples of a broad range of construction materials were exposed for periods up to 28 months in the a...

271

Simulation study supporting wastewater treatment plant upgrading  

Microsoft Academic Search

The paper presents a study where upgrading of an existing wastewater treatment plant was supported by simulation. The aim of the work was to decide between two technologies to improve nitrogen removal: a conventional activated sludge process (ASP) and a moving bed biofilm reactor (MBBR). To perform simulations, the mathematical models of both processes were designed. The models were calibrated

N. Hvala; D. Vrecko; O. Burica; M. Strazar; M. Levstek

272

Mechanisms of Cu2+ migration, recovery and detoxification in Cu2+-, SO4(2-) -containing wastewater treatment process with anaerobic granular sludge.  

PubMed

In this study, anaerobic granular sludge with sulphate-reducing bacteria (SRB) was applied to treat Cu2+-, SO4(2-) -containing wastewater in an expanded granular sludge bed reactor. The migration and enrichment of copper in anaerobic granular sludge were envaluated. By analysing the sludge with X-ray diffraction, copper was determined to be present as covellite (CuS) in the sludge. Observations at the microscopic level showed that CuS precipitates were absorbed onto granules and gradually migrated from the outer to the interior layer of the granule over time and finally accumulated in the core of the granular sludge. Because of the migration of the CuS precipitates and the protection of the extracellular polymeric substances matrix, SRB were able to tolerate copper concentrations up to 10 mg/L. A copper removal efficiency of about 96% was observed at a steady state for 3 months, and copper was enriched in the granular sludge. PMID:24956789

Cao, Xiaolei; Cao, Hongbin; Sheng, Yuxing; Xie, Yongbing; Zhang, Kai; Zhang, Yi; Crittenden, John C

2014-08-01

273

Wetlands for Wastewater Treatment  

Microsoft Academic Search

\\u000a This chapter discusses the use of natural and constructed wetlands for treatment of wastewaters. Mechanisms of treatment processes\\u000a for wetlands were described. Function, roles, types, and selection of wetland plants were discussed. This chapter also covers\\u000a design, monitoring, and maintenance of wetland treatment systems for wastewater. Case studies in Malaysia and UK were discussed.

Azni Idris; Abdul Ghani Liew Abdullah; Yung-Tse Hung; Lawrence K. Wang

274

SLUDGE TREATMENT AND DISPOSAL. VOLUME 1. SLUDGE TREATMENT  

EPA Science Inventory

This two volume set presents in detail technical design information for the following sludge treatment and disposal processes: lime stabilization, anaerobic digestion, aerobic digestion, thermal sludge conditioning, thickening, dewatering, and landfilling. The discussion of each ...

275

IMPROVED METHOD FOR RECOVERY OF ENTERIC VIRUSES FROM WASTEWATER SLUDGES  

EPA Science Inventory

Various parameters involved in recovering indigenous enteric viruses from wastewater sludges aided by buffered beef extract elution and subsequent organic flocculation concentration were examined. Conditions were optimized to yield an overall effective method for use in environme...

276

Improved Method for Recovery of Enteric Viruses from Wastewater Sludges.  

National Technical Information Service (NTIS)

Various parameters involved in recovering indigenous enteric viruses from wastewater sludges aided by buffered beef extract elution and subsequent organic flocculation concentration were examined. Conditions were optimized to yield an overall effective me...

C. J. Hurst T. Goyke

1986-01-01

277

Anaerobic SBR Treatment of Coal Conversion Wastewaters. Second Quarterly Report.  

National Technical Information Service (NTIS)

Development of both an operating strategy and a basis of design for Anaerobic Sequencing Batch Reactor (AnSBR) systems for treatment of coal conversion wastewaters is reported for two different systems: to develop a settleable granular sludge, typical of ...

L. H. Ketchum

1986-01-01

278

Microwave, ultrasonic and chemo-mechanical pretreatments for enhancing methane potential of pulp mill wastewater treatment sludge.  

PubMed

Microwave (2450 MHz, 1250 W), ultrasonic (20 kHz, 400 W) and chemo-mechanical (MicroSludge® with 900 mg/L NaOH followed by 83,000 kPa) pretreatments were applied to pulp mill waste sludge to enhance methane production and reduce digester sludge retention time. The effects of four variables (microwave temperature in a range of 50-175°C) and sonication time (15-90 min), sludge type (primary or secondary) and digester temperature (mesophilic and thermophilic) were investigated. Microwave pretreatment proved to be the most effective, increasing specific methane yields of WAS samples by 90% compared to controls after 21 days of mesophilic digestion. Sonication solubilized the sludge samples better, but resulted in soluble non-biodegradable compounds. Based on the laboratory scale data, MicroSludge® was found the least energy intensive pretreatment followed by sonication for 15 min alternative with net energy profits of 1366 and 386 kWh/tonne of total solids (TS), respectively. Pretreatment benefits were smaller for thermophilic digesters. PMID:21727004

Saha, Mithun; Eskicioglu, Cigdem; Marin, Juan

2011-09-01

279

Evaluation of the fate of perfluoroalkyl compounds in wastewater treatment plants  

Microsoft Academic Search

Recent studies have shown that the wastewater treatment plant (WWTP) is a significant source of perfluoroalkyl compounds (PFCs) in natural water. In this study, 10 PFCs were analyzed in influent and effluent wastewater and sludge samples in 15 municipal, 4 livestock and 3 industrial WWTPs in Korea. The observed distribution pattern of PFCs differed between the wastewater and sludge samples.

Rui Guo; Won-Jin Sim; Eung-Sun Lee; Ji-Hyun Lee; Jeong-Eun Oh

2010-01-01

280

Elimination of aromatic surfactants from municipal wastewaters: comparison of conventional activated sludge treatment and membrane biological reactor.  

PubMed

Behaviour of anionic surfactants of linear alkylbenzene sulphonates (LAS) type and non-ionic surfactants of nonylphenol polyethoxylate (NPnEO) type was studied in the conventional mechanical/biological sewage treatment plant (STP) as well as using a membrane biological reactor (MBR). LAS and NPnEO were determined using high performance liquid chromatography (HPLC) equipped with spectrofluorimetric detection. Liquid chromatography/tandem mass spectrometry (LC/MS/MS) was used for identification and quantification of stable metabolites, including nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO) and nonylphenoxy carboxylic acids (NPnEC). The study showed that aromatic surfactants belong to the most prominent constituents in the examined municipal wastewaters with typical LAS and NPnEO concentrations of 2-10 mg/L and 0.1-0.5 mg/L, respectively. The removal of aromatic surfactants in conventional STP showed well-known features reported in the literature, including an efficient microbial transformation of the parent molecules and formation of stable metabolic products. The elimination efficiency of aromatic surfactants using the MBR unit was higher than that in the conventional STP, while the composition of recalcitrant nonylphenolic residues in the effluent seems to be ecotoxicologically more favourable due to the lower contributions of the lipophilic metabolites. PMID:16004007

Terzic, S; Matosic, M; Ahel, M; Mijatovic, I

2005-01-01

281

SEPARATION OF METALS IN WASTEWATER SLUDGE BY CENTRIFUGAL CLASSIFICATION  

EPA Science Inventory

Municipal wastewater sludges frequently contain undesirably high concentrations of heavy metals and/or organic pollutants which interfere with beneficial use of sludge on farmland and with some disposal practices such as ocean disposal. Centrifugal classification is a low-cost pr...

282

Separation of metals in wastewater sludge by centrifugal classification  

Microsoft Academic Search

Municipal wastewater sludges frequently contain undesirably high concentrations of heavy metals and\\/or organic pollutants that interfere with beneficial use of sludge on farmland and with some disposal practices such as ocean disposal. Centrifugal classification is a low-cost procedure that has been demonstrated in the study to concentrate contaminants into the centrate stream, thus reducing the contaminants in the centrifuge cake

Carol Ann Fronk; Joseph B. Farrell; William Strachan

1985-01-01

283

Parasitic contamination in wastewater and sludge samples in Tunisia using three different detection techniques.  

PubMed

The limited availability of water results in the reuse of wastewater or sludge. The Tunisian wastewater regulatory guidelines have specific limits for ova of helminths (<1 egg/l) but none for protozoan parasites. We assessed the presence and loads of parasites in 20 samples of raw, treated wastewater and sludge collected from six wastewater treatment plants. Samples were tested by microscopy using the modified Bailenger method (MBM), immunomagnetic separation (IMS) followed by immunofluorescent assay microscopy, and PCR and sequence analysis for the protozoa Cryptosporidium and Giardia. The seven samples of raw wastewater had a high diversity of helminth and protozoa contamination. Giardia spp., Entamoeba histolytica/dispar, Entamoeba coli, Ascaris spp., Enterobius vermicularis, and Taenia saginata were detected by MBM, and protozoan loads were greater than helminth loads. Cryptosporidium and Giardia were also detected by IMS microscopy and PCR. Six of the eight samples of treated wastewater had parasites: helminths (n = 1), Cryptosporidium (n = 1), Giardia (n = 4), and Entamoeba (n = 4). Four of five samples of sludge had microscopically detectable parasites, and all had both Cryptosporidium and Giardia. The genotypes and subtypes of Cryptosporidium and Giardia were of both human and animal origin. These findings suggest that it may be important to monitor the presence of protozoan parasites in treated wastewater and sludge in Tunisia. PMID:20352447

Khouja, Layla Ben Ayed; Cama, Vitaliano; Xiao, Lihua

2010-06-01

284

Evaluation of advanced wastewater treatment systems for water reuse in the era of advanced wastewater treatment  

NASA Astrophysics Data System (ADS)

This study focuses on effluent COD concentration from wastewater treatment in regards to the reduction of pathogenic bacteria and trace substances in public waters. The main types of secondary wastewater treatment were conventional activated sludge processes. Recently, however, advance wastewater treatment processes have been developed aimed at the removal of nitrogen and phosphorus, and the effluent quality of these processes was analyzed in this study. Treatment processes for water reclamation that make effluent to meet the target water quality for reuse purposes were selected and also optimum design parameters for these processes were proposed. It was found that the treatment cost to water reclamation was greatly affected by the effluent COD of the secondary treatment. It is important to maintain low COD concentration in the secondary treated effluent. Therefore, it is considered that adequate cost benefits would be obtained by achieving target COD quality through shifting from a conventional activated sludge process to an advanced treatment process.

Kon, Hisao; Watanabe, Masahiro

285

Removal of carbon and nutrients from low strength domestic wastewater by expanded granular sludge bed-zeolite bed filtration (EGSB-ZBF) integrated treatment concept  

Microsoft Academic Search

The performance of an expanded granular sludge bed (EGSB) reactor coupled with zeolite bed filtration (ZBF) for treating low strength domestic wastewater was monitored at 35°C for 7 months. The whole operation period of EGSB system was divided into five phases. Each phase ran at up-flow velocity (m\\/h) of 0.51, 1.02, 3.57, 2.05, 9.69, and hydraulic retention time (HRT) (h)

Xiao-Ming Li; Liang Guo; Qi Yang; Guang-Ming Zeng; De-Xiang Liao

2007-01-01

286

Simultaneous biohydrogen production and starch wastewater treatment in an acidogenic expanded granular sludge bed reactor by mixed culture for long-term operation  

Microsoft Academic Search

The biofilm-based expanded granular sludge bed (EGSB) reactor was developed to treat starch-containing wastewater and simultaneously recovery hydrogen by mixed microbial culture. Granular activated carbon (GAC) was used as the support media. Operating at the temperature of 30°C for over 400 days (data not shown), the EGSB reactor presented high efficiency in hydrogen production and COD removal ability. The maximum

Wan-Qian Guo; Nan-Qi Ren; Zhao-Bo Chen; Bing-Feng Liu; Xiang-Jing Wang; Wen-Sheng Xiang; Jie Ding

2008-01-01

287

Anaerobic treatment of domestic wastewater in a membrane-coupled expended granular sludge bed (EGSB) reactor under moderate to low temperature  

Microsoft Academic Search

The performance of an expended granular sludge bed (EGSB) reactor coupled with hollow fibre membrane filtration for treating domestic wastewater was monitored during 7-month period in the range 11–25°C, and at the hydraulic retention time (HRT) of 3.5 to 5.7h. With temperatures above 15°C, the system was capable of removing 85–96% of total chemical oxygen demand (COD) and 83–94% of

Li-Bing Chu; Feng-Lin Yang; Xing-Wen Zhang

2005-01-01

288

Elimination of Cu(II) toxicity by powdered waste sludge (PWS) addition to an activated sludge unit treating Cu(II) containing synthetic wastewater  

Microsoft Academic Search

Copper(II) ion toxicity onto activated sludge organisms was eliminated by addition of powdered waste sludge (PWS) to the feed wastewater for removal of Cu(II) ions by biosorption before biological treatment. The synthetic feed wastewater containing 14 or 22mgl?1 Cu(II) was mixed with PWS in a mixing tank where Cu(II) ions were adsorbed onto PWS and the mixture was fed to

M. Yunus Pamukoglu; Fikret Kargi

2007-01-01

289

EVALUATION OF THE FULL-SCALE APPLICATION OF ANAEROBIC SLUDGE DIGESTION AT THE BLUE PLAINS WASTEWATER TREATMENT FACILITY, WASHINGTON, DC  

EPA Science Inventory

The mesophilic-thermophilic digestion process is a new two-step concept for treating municipal wasterwater sludges. The first step operates under mesophilic process conditions (digestion with anaerobic microorganisms that thrive at 90 to 100F). The second step operates under ther...

290

Sewage sludge treatment system  

NASA Technical Reports Server (NTRS)

Raw sewage may be presently treated by mixing screened raw sewage with activated carbon. The mixture is then allowed to stand in a first tank for a period required to settle the suspended matter to the bottom of the tank as a sludge. Thereafter, the remaining liquid is again mixed with activated carbon and the mixture is transferred to a secondary settling tank, where it is permitted to stand for a period required for the remaining floating material to settle as sludge and for adsorption of sewage carbon as well as other impurities to take place. The sludge from the bottom of both tanks is removed and pyrolyzed to form activated carbon and ash, which is mixed with the incoming raw sewage and also mixed with the liquid being transferred from the primary to the secondary settling tank. It has been found that the output obtained by the pyrolysis process contains an excess amount of ash. Removal of this excess amount of ash usually also results in removing an excess amount of carbon thereby requiring adding carbon to maintain the treatment process. By separately pyrolyzing the respective sludges from the first and second settling tanks, and returning the separately obtained pyrolyzed material to the respective first and second tanks from which they came, it has been found that the adverse effects of the excessive ash buildup is minimized, the carbon yield is increased, and the sludge from the secondary tank can be pyrolyzed into activated carbon to be used as indicated many more times than was done before exhaustion occurs.

Kalvinskas, John J. (Inventor); Mueller, William A. (Inventor)

1976-01-01

291

Color removal from cotton textile industry wastewater in an activated sludge system with various additives  

Microsoft Academic Search

The low biodegradability of many dyes and textile chemicals indicates that biological treatment is not always successful in the treatment of cotton textile wastewater, in terms of color removal. In this study, a specific organic flocculant (Marwichem DEC), powdered activated carbon (PAC), bentonite, activated clay and commercial synthetic inorganic clay (Macrosorb) were directly added into the activated sludge laboratory pilot

Ay?egül Pala; Enis Tokat

2002-01-01

292

Enantiomeric determination of azole antifungals in wastewater and sludge by liquid chromatography-tandem mass spectrometry.  

PubMed

A sensitive and reliable liquid chromatographic-tandem mass spectrometric method for enantiomeric determination of five chiral azole antifungals (econazole, ketoconazole, miconazole, tebuconazole, and propiconazole) in wastewater and sludge has been established and validated. An isotope-labeled internal standard was used for quantification. Recovery of the individual enantiomers was usually in the range of 77-102 % for wastewater and 71-95 % for sludge, with relative standard deviations within 20 %. No significant difference (p>0.05) was observed between recovery of pairs of enantiomers of the chiral azole antifungals except for those of tebuconazole. Method quantification limits for individual enantiomers were 0.3-10 ng L(-1) and 3-29 ng g(-1) dry weight for wastewater and sludge, respectively. The method was used to investigate the enantiomeric composition of the azole pharmaceuticals in wastewater and sludge samples from a sewage treatment plant in China. Enantiomers of miconazole, ketoconazole, and econazole were widely detected. The results showed that the azole antifungals in wastewater and sludge were generally racemic or marginally non-racemic. The method is a useful tool for investigation of the enantiomeric occurrence, behavior, and fate of the chiral azole antifungals in the environment. PMID:22526654

Huang, Qiuxin; Zhang, Kun; Wang, Zhifang; Wang, Chunwei; Peng, Xianzhi

2012-06-01

293

Formation and impact of granules in fostering clean energy production and wastewater treatment in upflow anaerobic sludge blanket (UASB) reactors  

Microsoft Academic Search

Anaerobic reactors have acquired a new relevance in recent years due to their ability to generate methane from biodegradable wastewaters—thereby producing clean energy. Methane capture in this manner also prevents the escape of the greenhouse gas to the atmosphere which otherwise occurs when anaerobic conditions develop in drains and outfalls carrying wastewater. Of all the different types of anaerobic reactors

Tasneem Abbasi; S. A. Abbasi

2012-01-01

294

Removal of phosphorus from agricultural wastewaters using adsorption media prepared from acid mine drainage sludge  

USGS Publications Warehouse

Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A??cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid mine drainage sludge is a waste product produced by the neutralization of acid mine drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the removal of phosphorus. In this paper, we describe a method for the drying and pelletization of acid mine drainage sludge that results in a particulate media, which we have termed Ferroxysorb, for the removal of phosphorus from wastewater in an efficient packed bed contactor. Adsorption capacities are high, and kinetics rapid, such that a contact time of less than 5 min is sufficient for removal of 60-90% of the phosphorus, depending on the feed concentration and time in service. In addition, the adsorption capacity of the Ferroxysorb media was increased dramatically by using two columns in an alternating sequence so that each sludge bed receives alternating rest and adsorption cycles. A stripping procedure based on treatment with dilute sodium hydroxide was also developed that allows for recovery of the P from the media, with the possibility of generating a marketable fertilizer product. These results indicate that acid mine drainage sludges - hitherto thought of as undesirable wastes - can be used to remove phosphorus from wastewater, thus offsetting a portion of acid mine drainage treatment costs while at the same time improving water quality in sensitive watersheds.

Sibrell, Philip L.; Montgomery, Gary A.; Ritenour, Kelsey L.; Tucker, Travis W.

2009-01-01

295

Integration of anammox into the aerobic granular sludge process for main stream wastewater treatment at ambient temperatures  

Microsoft Academic Search

Anaerobic ammonium oxidation, nitrification and removal of COD was studied at ambient temperature (18 °C ± 3) in an anoxic\\/aerobic granular sludge reactor during 390 days. The reactor was operated in a sequencing fed batch mode and was fed with acetate and ammonium containing medium with a COD\\/N ratio of 0.5 [g COD\\/gN]. During influent addition, the medium was mixed with recycled effluent

Mari K. H. Winkler; Robbert Kleerebezem; Mark C. M. van Loosdrecht

296

Effects of dissolved oxygen on biological nitrogen removal in integrated fixed film activated sludge (IFAS) wastewater treatment process  

Microsoft Academic Search

The objective of this research was to determine the effects of dissolved oxygen on the biological nitrogen removal in the Integrated Fixed Film Activated Sludge (IFAS) and Modified Ludzack-Ettinger (MLE) systems. The carbonaceous and nitrogen removals were investigated at the COD\\/Nitrogen (C\\/N) ratios of 4, 6, and 10, and the dissolved oxygen (DO) concentrations of 2, 4, and 6 mg\\/L.

Tongchai Sriwiriyarat; Wiyaporn Ungkurarate; Prayoon Fongsatitkul; Sopa Chinwetkitvanich

2008-01-01

297

Utilization of AMD sludges from the anthracite region of Pennsylvania for removal of phosphorus from wastewater  

USGS Publications Warehouse

Excess phosphorus (P) inputs from human sewage, animal feeding operations, and nonpoint source discharges to the environment have resulted in the eutrophication of sensitive receiving bodies of water such as the Great Lakes and Chesapeake Bay. Phosphorus loads in wastewater discharged from such sources can be decreased by conventional treatment with iron and aluminum salts but these chemical reagents are expensive or impractical for many applications. Acid mine drainage (AMD) sludges are an inexpensive source of iron and aluminum hydrous oxides that could offer an attractive alternative to chemical reagent dosing for the removal of P from local wastewater. Previous investigations have focused on AMD sludges generated in the bituminous coal region of western Pennsylvania, and confirmed that some of those sludges are good sorbents for P over a wide range of operating conditions. In this study, we sampled sludges produced by AMD treatment at six different sites in the anthracite region of Pennsylvania for potential use as P sequestration sorbents. Sludge samples were dried, characterized, and then tested for P removal from water. In addition, the concentrations of acid-extractable metals and other impurities were investigated. Test results revealed that sludges from four of the sites showed good P sorption and were unlikely to add contaminants to treated water. These results indicate that AMD sludges could be beneficially used to sequester P from the environment, while at the same time decreasing the expense of sludge disposal.

Sibrell, P.L.; Cravotta, C.A., III; Lehman, W.G.; Reichert, W.

2010-01-01

298

Concentrations and inactivation of Ascaris eggs and pathogen indicator organisms in wastewater stabilization pond sludge.  

PubMed

During treatment in wastewater stabilization ponds (WSPs) many pathogens, in particular helminth eggs, are concentrated in the sludge layer. Because periodic removal of the sludge is often required, information is needed on the concentrations and inactivation of pathogens in the sludge layer to evaluate the public health risk they pose upon removal of the sludge. In this paper, previous reports on the sludge concentrations of various pathogen indicator organisms and helminth eggs are reviewed and results from our own recent experiments are reported. The advantages and disadvantages of several methods for studying inactivation in the sludge layer are discussed, as well as implications for the management of WSP sludge. In our recent experiments, which were conducted at three WSPs in central Mexico, sludge cores, dialysis chambers, and batch experiments were used to measure the inactivation rates of fecal coliform bacteria, fecal enterococci, F+ coliphage, somatic coliphage, and Ascaris eggs. The first-order inactivation rate constants were found to be approximately 0.1, 0.1, 0.01, 0.001, and 0.001 d(-1), respectively. The concentrations of all the organisms were found to vary both vertically and horizontally in the sludge layer; therefore, to determine the maximum and average concentration of organisms in the sludge layer of a WSP, complete sludge cores must be collected from representative locations throughout the pond. PMID:14510198

Nelson, K L

2003-01-01

299

Process Design Manual: Wastewater Treatment Facilities for Sewered Small Communities.  

ERIC Educational Resources Information Center

This manual attempts to describe new treatment methods, and discuss the application of new techniques for more effectively removing a broad spectrum of contaminants from wastewater. Topics covered include: fundamental design considerations, flow equalization, headworks components, clarification of raw wastewater, activated sludge, package plants,…

Leffel, R. E.; And Others

300

Rapid quantification of bacteria and viruses in influent, settled water, activated sludge and effluent from a wastewater treatment plant using flow cytometry.  

PubMed

As microbiological parameters are important in monitoring the correct operation of wastewater treatment plants and controlling the microbiological quality of wastewater, the abundances of total bacteria (including intact and damaged bacterial cells) and total viruses in wastewater were investigated using a combination of ultrasonication and flow cytometry. The comparisons between flow cytometry (FCM) and other cultivation-independent methods (adenosine tri-phosphate (ATP) analysis for bacteria enumeration and epifluorescence microscopy (EFM) for virus enumeration) gave very similar patterns of microbial abundance changes, suggesting that FCM is suitable for targeting and obtaining reliable counts for bacteria and viruses in wastewater samples. The main experimental results obtained were: (1) effective removal of total bacteria in wastewater, with a decrease from an average concentration of 1.74 × 10(8)counts ml(-1) in raw wastewater to 3.91 × 10(6)counts ml(-1) in the effluent, (2) compared to influent raw wastewater, the average concentration of total viruses in the treated effluent (3.94 × 10(8)counts ml(-1)) exhibited no obvious changes, (3) the applied FCM approach is a rapid, easy, and convenient tool for understanding the microbial dynamics and monitoring microbiological quality in wastewater treatment processes. PMID:24185058

Ma, Lili; Mao, Guannan; Liu, Jie; Yu, Hui; Gao, Guanghai; Wang, Yingying

2013-01-01

301

Use of Filamentous Fungi for Wastewater Treatment and Production of High Value Fungal Byproducts: A Review  

Microsoft Academic Search

Conventional biological wastewater treatment generates large amounts of low value bacterial biomass. The treatment and disposal of this excess bacterial biomass, also known as waste activated sludge, accounts for about 40–60% of the wastewater treatment plant operation cost. A different form of biomass with a higher value could significantly change the economics of wastewater treatment. Fungi could offer this benefit

Sindhuja Sankaran; Samir Kumar Khanal; Nagapadma Jasti; Bo Jin; Anthony L. Pometto III; J. Hans Van Leeuwen

2010-01-01

302

Production of polyhydroxyalcanoates (PHAs) using milk whey and dairy wastewater activated sludge production of bioplastics using dairy residues.  

PubMed

The production of polyhydroxyalcanoates (PHAs), which are biodegradable plastics, was studied using milk whey and dairy wastewater activated sludge to define a suitable C/N ratio, the pre-treatments required to reduce the protein content, and the effect of pH correction. The results show good production of PHAs at a C/N=50 and without pH correction. The use of dairy wastewater activated sludge has the advantage of not requiring aseptic conditions. PMID:20226388

Bosco, Francesca; Chiampo, Fulvia

2010-04-01

303

Onsite Wastewater Treatment Systems Manual.  

National Technical Information Service (NTIS)

The U.S. Environmental Protection Agency is pleased to publish the Onsite Wastewater Treatment Systems Manual. This manual provides up-to-date information on onsite wastewater treatment system (OWTS) siting, design, installation, maintenance, and replacem...

2002-01-01

304

COLLECTION, TREATMENT, AND DISPOSAL OF SLUDGE FROM SMALL COMMUNITIES: U.S. EXPERIENCE  

EPA Science Inventory

Sludge treatment represents almost half the cost of wastewater treatment at many facilities in the U.S. Although sludge problems are of serious concern everywhere, they are different for different locations. The approach to sludge handling and the solution to problems depends on ...

305

Capital and Operating Costs of Full-Scale Fecal Sludge Management and Wastewater Treatment Systems in Dakar, Senegal  

PubMed Central

A financial comparison of a parallel sewer based (SB) system with activated sludge, and a fecal sludge management (FSM) system with onsite septic tanks, collection and transport (C&T) trucks, and drying beds was conducted. The annualized capital for the SB ($42.66 capita–1 year–1) was ten times higher than the FSM ($4.05 capita–1 year–1), the annual operating cost for the SB ($11.98 capita–1 year–1) was 1.5 times higher than the FSM ($7.58 capita–1 year–1), and the combined capital and operating for the SB ($54.64 capita–1 year–1) was five times higher than FSM ($11.63 capita–1 year–1). In Dakar, costs for SB are almost entirely borne by the sanitation utility, with only 6% of the annualized cost borne by users of the system. In addition to costing less overall, FSM operates with a different business model, with costs spread among households, private companies, and the utility. Hence, SB was 40 times more expensive to implement for the utility than FSM. However, the majority of FSM costs are borne at the household level and are inequitable. The results of the study illustrate that in low-income countries, vast improvements in sanitation can be affordable when employing FSM, whereas SB systems are prohibitively expensive.

2012-01-01

306

Priority and emerging pollutants in sewage sludge and fate during sludge treatment.  

PubMed

This paper aims at characterizing the quality of different treated sludges from Paris conurbation in terms of micropollutants and assessing their fate during different sludge treatment processes (STP). To achieve this, a large panel of priority and emerging pollutants (n=117) have been monitored in different STPs from Parisian wastewater treatment plants including anaerobic digestion, thermal drying, centrifugation and a sludge cake production unit. Considering the quality of treated sludges, comparable micropollutant patterns are found for the different sludges investigated (in mg/kg DM - dry matter). 35 compounds were detected in treated sludges. Some compounds (metals, organotins, alkylphenols, DEHP) are found in every kinds of sludge while pesticides or VOCs are never detected. Sludge cake is the most contaminated sludge, resulting from concentration phenomenon during different treatments. As regards treatments, both centrifugation and thermal drying have broadly no important impact on sludge contamination for metals and organic compounds, even if a slight removal seems to be possible with thermal drying for several compounds by abiotic transfers. Three different behaviors can be highlighted in anaerobic digestion: (i) no removal (metals), (ii) removal following dry matter (DM) elimination (organotins and NP) and iii) removal higher than DM (alkylphenols - except NP - BDE 209 and DEHP). Thus, this process allows a clear removal of biodegradable micropollutants which could be potentially significantly improved by increasing DM removal through operational parameters modifications (retention time, temperature, pre-treatment, etc.). PMID:24797622

Mailler, R; Gasperi, J; Chebbo, G; Rocher, V

2014-07-01

307

Feasibility study: Codisposal with energy recovery from wastewater sludge and municipal refuse. Phase 2, Gloucester County, New Jersey  

NASA Astrophysics Data System (ADS)

The feasibility of thermal reduction of dewatered sludge and mixed municipal refuse with steam recovery for generation of electricity is investigated. The Gloucester County Utilities Authority wastewater treatment complex would produce the sludge and benefit from the generated electricity from a waste to energy system located on adjacent property.

1981-07-01

308

Anaerobic SBR treatment of coal conversion wastewaters. Second quarterly report  

SciTech Connect

Development of both an operating strategy and a basis of design for Anaerobic Sequencing Batch Reactor (AnSBR) systems for treatment of coal conversion wastewaters is reported for two different systems: to develop a settleable granular sludge, typical of Anaerobic Up-Flow Sludge Blanket Reactors; and a treatment without developing granular sludges. In the second case, development of more elaborate solids-liquid-gas separation systems may be required. Acclimation studies continue to develop anaerobic sludges better acclimated to treatment constituents common in coal conversion wastewater. Screening studies, in 100 mL to 500 mL serum-bottles, are being conducted to determine treatability and where possible, identify degradation rates and pathways of these coal conversion wastewater constituents, commonly, phenol, aniline, o-cresol, m-cresol, p-cresol, ammonia nitrogen, volatile acids, cyanide, thiocyanide, and xylenes.

Ketchum, L.H. Jr.

1986-04-04

309

Determination of 4'-isobutylacetophenone and other transformation products of anti-inflammatory drugs in water and sludge from five wastewater treatment plants in Sweden by hollow fiber liquid phase microextraction and gas chromatography-mass spectrometry.  

PubMed

This work describes the development of a two-phase hollow fiber liquid phase microextraction method for the determination of three hydrophobic transformation products of the nonsteroidal anti-inflammatory drugs ketoprofen, ibuprofen and diclofenac: 3-acetobenzophenone, 4´-isobutylacetophenone and diclofenac amide. The optimized method involved extraction for 180min at a stirring speed of 440rpm. Hollow fibers (0.6mm i.d.) of 6cm length were employed and the acceptor phase consisted of 1-octanol. 5% Sodium chloride was added to samples to prevent loss of the solvent during extraction. Extracts were analyzed by GC-MS and method detection limits were in the range of 1.6-5.6ngL(-1). The method was applied for the determination of target analytes in influent samples from five Swedish wastewater treatment plants (WWTPs). All three analytes were found in very low or non-detectable concentrations. The most abundant compound was 3-acetobenzophenone found at four of the investigated WWTPs at an average concentration of 62ngL(-1). Diclofenac amide and 4'-isobutylacetophenone were only detected above LOD at one WWTP each at a concentration of 55 and 197ngL(-1), respectively. Samples of water entering and exiting the activated sludge treatment as well as digested sludge were also collected from one of the WWTPs. Only diclofenac amide was detected in these samples. A higher concentration was detected in the effluent from the activated sludge treatment than the influent, thus indicating the formation of this compound during treatment. In the sludge, diclofenac amide was detected at 183ngg(-1)wet weight. Based on these results it can be concluded that the amounts of these compounds reaching WWTPs are very small, suggesting negligible risks to the aquatic environment. However, they also indicate the potential formation during the activated sludge process and accumulation into sludge for at least one of the compounds which is why further studies of these processes are needed. PMID:24840419

Manso, Jose; Larsson, Estelle; Jönsson, Jan Åke

2014-07-01

310

UTILIZATION OF MUNICIPAL WASTEWATER AND SLUDGE ON LAND, PROCEEDINGS OF THE 1983 WORKSHOP  

EPA Science Inventory

A workshop on Utilization of Municipal Wastewater and Sludge on Land was held in Denver, Colorado from February 23 through 25, 1983. Researchers and practioners of land treatment, totaling 203 in number and from the United States and other countries were invited to attend and eva...

311

THE SOURCES AND BEHAVIOR OF HEAVY METALS IN WASTEWATER AND SLUDGES  

EPA Science Inventory

A critical evaluation has been made of the literature regarding the sources of heavy metals in sludges from municipal wastewater treatment plants. Residential loadings of heavy metals as a percentage of total metal loads are highly variable with respect to both the particular ele...

312

Utilization of Municipal Wastewater and Sludge on Land, Proceedings of the 1983 Workshop.  

National Technical Information Service (NTIS)

A workshop on Utilization of Municipal Wastewater and Sludge on Land was held in Denver, Colorado from February 23 through 25, 1983. Researchers and practioners of land treatment, totaling 203 in number and from the United States and other countries were ...

A. L. Page, I. K. Iskandar, J. E. Smith, L. E. Sommers, T. L. Gleason

1984-01-01

313

Disinfection. [Wastewater treatment  

SciTech Connect

Methods of disinfection of wastewater including chlorination, ultraviolet radiation, ozone, and quaternary compounds are reviewed. Various analytical methods to detect residues of the disinfectants are described. The production of inorganic and nonvolatile organic compounds in conventional water treatment processes is reviewed. (KRM)

Haas, C.N. (Illinois Inst. of Technology, Chicago); McCreary, J.J.

1982-06-01

314

Microalgae and wastewater treatment  

PubMed Central

Organic and inorganic substances which were released into the environment as a result of domestic, agricultural and industrial water activities lead to organic and inorganic pollution. The normal primary and secondary treatment processes of these wastewaters have been introduced in a growing number of places, in order to eliminate the easily settled materials and to oxidize the organic material present in wastewater. The final result is a clear, apparently clean effluent which is discharged into natural water bodies. This secondary effluent is, however, loaded with inorganic nitrogen and phosphorus and causes eutrophication and more long-term problems because of refractory organics and heavy metals that are discharged. Microalgae culture offers an interesting step for wastewater treatments, because they provide a tertiary biotreatment coupled with the production of potentially valuable biomass, which can be used for several purposes. Microalgae cultures offer an elegant solution to tertiary and quandary treatments due to the ability of microalgae to use inorganic nitrogen and phosphorus for their growth. And also, for their capacity to remove heavy metals, as well as some toxic organic compounds, therefore, it does not lead to secondary pollution. In the current review we will highlight on the role of micro-algae in the treatment of wastewater.

Abdel-Raouf, N.; Al-Homaidan, A.A.; Ibraheem, I.B.M.

2012-01-01

315

Wastewater treatment with microalgae  

Microsoft Academic Search

In locations where total solar energy inputs average 400 langeleys or more, microscopic algae, grown in properly designed ponds, can contribute significantly and economically to wastewater treatment. While growing, microalgae produce an abundance of oxygen for microbial and biochemical oxidation of organics and other reduced compounds and for odor control. Microalgae also accelerate the inactivation of disease bacteria and parasitic

Oswald

1992-01-01

316

IMPROVING HOUSEHOLD WASTEWATER TREATMENT  

Microsoft Academic Search

Many rural and suburban homes and virtually all farmsteads use a septic system or similar onsite waste- water treatment system. While these systems are generally economical and safe, household wastewater can contain contaminates that degrade water quality for such uses as drinking, stock watering, food preparation and cleaning. A properly designed, installed, and maintained system minimizes the impact of that

Anthony Tyson

317

Integrating anaerobic processes into wastewater treatment.  

PubMed

Over the past decade, the concept of anaerobic processes for the treatment of low temperature domestic wastewater has been introduced. This paper uses a developed wastewater flowsheet model and experimental data from several pilot scale studies to establish the impact of integrating anaerobic process into the wastewater flowsheet. The results demonstrate that, by integrating an expanded granular sludge blanket reactor to treat settled wastewater upstream of the activated sludge process, an immediate reduction in imported electricity of 62.5% may be achieved for a treated flow of c. 10,000 m(3) d(-1). This proposed modification to the flowsheet offers potential synergies with novel unit processes including physico-chemical ammonia removal and dissolved methane recovery. Incorporating either of these unit operations can potentially further improve the flowsheet net energy balance to between +0.037 and +0.078 kWh m(-3) of produced water. The impact of these secondary unit operations is significant as it is this contribution to the net energy balance that facilitates the shift from energy negative to energy positive wastewater treatment. PMID:21508551

McAdam, E J; Lüffler, D; Martin-Garcia, N; Eusebi, A L; Lester, J N; Jefferson, B; Cartmell, E

2011-01-01

318

Operation, Maintenance and Management of Wastewater Treatment Facilities: A Bibliography of Technical Documents.  

ERIC Educational Resources Information Center

This is an annotated bibliography of wastewater treatment manuals. Fourteen manuals are abstracted including: (1) A Planned Maintenance Management System for Municipal Wastewater Treatment Plants; (2) Anaerobic Sludge Digestion, Operations Manual; (3) Emergency Planning for Municipal Wastewater Treatment Facilities; (4) Estimating Laboratory Needs…

Himes, Dottie

319

Application of ionic liquids for the removal of heavy metals from wastewater and activated sludge.  

PubMed

This paper presents the results of adsorption studies on the removal of heavy metals (Cr, Cu, Cd, Ni, Pb and Zn) from standard solutions, real wastewater samples and activated sewage sludge using a new technique of liquid-liquid extraction using quaternary ammonium and phosphonium ionic liquids (ILs). Batch sorption experiments were conducted using the ILs [PR4][TS], [PR4][MTBA], [A336][TS] and [A336][MTBA]. Removal of these heavy metals from standard solutions were not effective, however removal of heavy metals from the industrial effluents/wastewater treatment plants were satisfactory, indicating that the removal depends mainly on the composition of the wastewater and cannot be predicted with standard solutions. Removal of heavy metals from activated sludge proved to be more successful than conventional methods such as incineration, acid extraction, thermal treatment, etc. For the heavy metals Cu, Ni and Zn, ?90% removal was achieved. PMID:22546790

Fuerhacker, Maria; Haile, Tadele Measho; Kogelnig, Daniel; Stojanovic, Anja; Keppler, Bernhard

2012-01-01

320

Microalgae and wastewater treatment.  

PubMed

The performance of microalgae aquaculture wastewater treatment system predominated mainly by Scenedesmus and Chlorella was assessed. Treatment induced a progressive reduction in both COD and BOD to values below the discharge limits. Different patterns were obtained for removal of phosphorus, nitrogen, and ammonia; however, the algal culture efficiencies reached 100% in their removal by the end of the treatment period. The applied aquatic systems demonstrated percentage reduction of heavy metals in the range between 52.3 and 100% in the batch system and 64.2 and 100% in the continuous system. Wastewater supported algal growth by inducing the incorporation of a significantly higher content of the individual amino acids Asp, Thr, Ser, Glu, Gly, and Tyr, and a markedly higher level of Pro. However, His, Lys, and Arg were markedly reduced compared to their levels in synthetic-medium-grown algae. PMID:7498057

Hammouda, O; Gaber, A; Abdel-Raouf, N

1995-08-01

321

A fullerene colloidal suspension stimulates the growth and denitrification ability of wastewater treatment sludge-derived bacteria.  

PubMed

Fullerene (C60) is a nanoparticle that has been widely studied and applied in numerous commodities. However, there are concerns regarding its potential negative impact on the environment. A fullerene colloidal suspension (nC60) is known for its property of selectively inhibiting the growth of microorganisms. In this study, using denaturing gradient gel electrophoresis fingerprinting technology, we found that fullerene altered the structure of a sludge-derived microbial community. Specifically, the bacteria from Bacillus, Acidovorax and Cloacibacterium genera were enriched in abundance when supplemented with nC60 at pH 6.5 under aerobic conditions. The effects of the fullerene colloidal suspension on a strain of Bacillus isolated from the same microbial community were evaluated to further characterize the growth-stimulating effect of nC60. The biomass of cultures of this strain incubated with nC60 concentrations ranging from 3mgL(-1) to 7mgL(-1) was approximately twice that of the control during the stationary phase. The fullerene also induced higher superoxide dismutase activity in Bacillus cereus. Furthermore, the nitrate removal rate of B. cereus increased to nearly 55% in the presence of 5mgL(-1) nC60, compared to 35% for the control. Meanwhile, the cumulative loading amount of nitrite was reduced from 33?gmL(-1) to 25?gmL(-1) by the addition of 5mgL(-1) nC60. Our results demonstrate that the fullerene colloidal suspension is conditionally capable of promoting the growth and denitrification metabolism of certain bacteria, such as B. cereus. Fullerene might have both inhibitory and stimulatory effects on microorganisms in various environments. PMID:24630252

Huang, Fei; Ge, Ling; Zhang, Bo; Wang, Yun; Tian, Hao; Zhao, Liping; He, Yiliang; Zhang, Xiaojun

2014-08-01

322

Persistence of pathogenic prion protein during simulated wastewater treatment processes  

USGS Publications Warehouse

Transmissible spongiform encephalopathies (TSEs, prion diseases) are a class of fatal neurodegenerative diseases affecting a variety of mammalian species including humans. A misfolded form of the prion protein (PrP TSE) is the major, if not sole, component of the infectious agent. Prions are highly resistant to degradation and to many disinfection procedures suggesting that, if prions enter wastewater treatment systems through sewers and/or septic systems (e.g., from slaughterhouses, necropsy laboratories, rural meat processors, private game dressing) or through leachate from landfills that have received TSE-contaminated material, prions could survive conventional wastewater treatment Here, we report the results of experiments examining the partitioning and persistence of PrPTSE during simulated wastewater treatment processes including activated and mesophilic anaerobic sludge digestion. Incubation with activated sludge did not result in significant PrPTSE degradation. PrPTSE and prion infectivity partitioned strongly to activated sludge solids and are expected to enter biosolids treatment processes. A large fraction of PrPTSE survived simulated mesophilic anaerobic sludge digestion. The small reduction in recoverable PrPTSE after 20-d anaerobic sludge digestion appeared attributable to a combination of declining extractability with time and microbial degradation. Our results suggest that if prions were to enter municipal wastewater treatment systems, most would partition to activated sludge solids, survive mesophilic anaerobic digestion, and be present in treated biosolids. ?? 2008 American Chemical Society.

Hinckley, G. T.; Johnson, C. J.; Jacobson, K. H.; Bartholomay, C.; Mcmahon, K. D.; Mckenzie, D.; Aiken, J. M.; Pedersen, J. A.

2008-01-01

323

Persistence of pathogenic prion protein during simulated wastewater treatment processes.  

PubMed

Transmissible spongiform encephalopathies (TSEs, prion diseases) are a class of fatal neurodegenerative diseases affecting a variety of mammalian species including humans. A misfolded form of the prion protein (PrP(TSE)) is the major, if not sole, component of the infectious agent. Prions are highly resistant to degradation and to many disinfection procedures suggesting that, if prions enter wastewater treatment systems through sewers and/or septic systems (e.g., from slaughterhouses, necropsy laboratories, rural meat processors, private game dressing) or through leachate from landfills that have received TSE-contaminated material, prions could survive conventional wastewater treatment. Here, we report the results of experiments examining the partitioning and persistence of PrPTSE during simulated wastewater treatment processes including activated and mesophilic anaerobic sludge digestion. Incubation with activated sludge did not result in significant PrPTSE degradation. PrPTSE and prion infectivity partitioned strongly to activated sludge solids and are expected to enter biosolids treatment processes. A large fraction of PrPTSE survived simulated mesophilic anaerobic sludge digestion. The small reduction in recoverable PrPTSE after 20-d anaerobic sludge digestion appeared attributable to a combination of declining extractability with time and microbial degradation. Our results suggest that if prions were to enter municipal wastewater treatment systems, most would partition to activated sludge solids, survive mesophilic anaerobic digestion, and be present in treated biosolids. PMID:18754377

Hinckley, Glen T; Johnson, Christopher J; Jacobson, Kurt H; Bartholomay, Christian; McMahon, Katherine D; McKenzie, Debbie; Aiken, Judd M; Pedersen, Joel A

2008-07-15

324

A STUDY OF FORCED AERATION COMPOSTING OF WASTEWATER SLUDGE  

EPA Science Inventory

The overall study objective was to make an independent assessment of the forced aeration wastewater sludge composting method as practiced at Beltsville, Maryland and Bangor, Maine. A number of visits were made to both sites to observe operations under all weather conditions and t...

325

Two Devices for Removing Sludge From Bioreactor Wastewater  

NASA Technical Reports Server (NTRS)

Two devices a magnetic separator and a special filter denoted a self-regenerating separator (SRS) have been developed for separating sludge from the stream of wastewater from a bioreactor. These devices were originally intended for use in microgravity, but have also been demonstrated to function in normal Earth gravity. The magnetic separator (see Figure 1) includes a thin-walled nonmagnetic, stainless-steel cylindrical drum that rotates within a cylindrical housing. The wastewater enters the separator through a recirculation inlet, and about 80 percent of the wastewater flow leaves through a recirculation outlet. Inside the drum, a magnet holder positions strong permanent magnets stationary and, except near a recirculation outlet, close to the inner drum surface. To enable magnetic separation, magnetite (a ferromagnetic and magnetically soft iron oxide) powder is mixed into the bioreactor wastewater. The magnetite becomes incorporated into the sludge by condensation, onto the powder particles, of microbe flocks that constitute the sludge. As a result, the magnets inside the drum magnetically attract the sludge onto the outer surface of the drum.

Archer, Shivaun; Hitchens, G. DUncan; Jabs, Harry; Cross, Jennifer; Pilkinton, Michelle; Taylor, Michael

2007-01-01

326

ELECTROPLATING PLANT OPERATING CONDITIONS RELATED TO WASTEWATER SLUDGE LEACHABILITY  

EPA Science Inventory

The objective of this project was to characterize the operating variables and wastewater sludges from six electroplating plants conducting a wide variety of plating operations so that the information developed would be applicable on an industry-wide basis. The results of the stud...

327

Evaluation of Municipal Wastewater Treatment Plant Activated Sludge for Biodegradation of Propylene Glycol as an Aircraft Deicing Fluid.  

National Technical Information Service (NTIS)

Aircraft deicing fluid used at airport facilities is often collected for treatment or disposal in order to prevent serious ecological threats to nearby surface waters. This study investigated lab scale degradation of propylene glycol (PG), the active ingr...

J. D. Delorit

2012-01-01

328

Wastewater treatment of pulp and paper industry: a review.  

PubMed

Pulp and paper industries generate varieties of complex organic and inorganic pollutants depending upon the type of the pulping process. A state-of-art of treatment processes and efficiencies of various wastewater treatment is presented and critically reviewed in this paper. Process description, source of wastewater and their treatment is discussed in detail. Main emphasis is given to aerobic and anaerobic wastewater treatment. In pulp and paper mill wastewater treatment aerobic treatment includes activated sludge process, aerated lagoons and aerobic biological reactors. UASB, fluidized bed, anaerobic lagoon and anaerobic contact reactors are the main technologies for anaerobic wastewater treatment. It is found that the combination of anaerobic and aerobic treatment processes is much efficient in the removal of soluble biodegradable organic pollutants. Color can be removed effectively by fungal treatment, coagulation, chemical oxidation, and ozonation. Chlorinated phenolic compounds and adsorable organic halides (AOX) can be efficiently reduced by adsorption, ozonation and membrane filtration techniques. PMID:23033705

Kansal, Ankur; Siddiqui, Nihalanwar; Gautam, Ashutosh

2011-04-01

329

Wastewater treatment as an energy production plant  

NASA Astrophysics Data System (ADS)

The objective of this research was to investigate the potential for net energy production at a Wastewater Treatment Plant (WWTP). Historically, wastewater treatment plants have been designed with the emphasis on process reliability and redundancy; efficient utilization of energy has not received equal consideration. With growing demands for energy and increased budgetary pressures in funding wastewater treatment plant costs, methods of reducing energy consumption and operating costs were explored in a new and novel direction pointed towards energy production rather than energy consumption. To estimate the potential for net energy production, a quantitative analysis was performed using a mathematical model which integrates the various unit operations to evaluate the overall plant energy balance. Secondary treatment performance analysis is included to ensure that the energy evaluation is consistent with plant treatment needs. Secondary treatment performance was conducted for activated sludge, trickling filters and RBCs. The equations for the mathematical model were developed independently for each unit operation by writing mass balance equations around the process units. The process units evaluated included those for preliminary treatment, primary treatment, secondary treatment, disinfection, and sludge treatment. Based on an analysis of both energy reduction and energy recovery methods, it was shown that net energy production at a secondary WWTP is possible utilizing technologies available today. Such technologies include those utilized for plant operations, as well as for energy recovery. The operation of fuel cells using digester gas represents one of the most significant new opportunities for energy recovery at wastewater facilities. The analysis predicts that a trickling filter WWTP utilizing commercial phosphoric acid fuel cells to recover energy from digester gas can provide for facility energy needs and have both electrical and thermal energy available for export. The use of fuel cells at an activated sludge or RBC WWTP is projected to produce all of the plant's thermal energy requirements and a significant amount of the electrical energy needs. With continued fuel cell development, it is expected that the 21st century will see all types of wastewater treatments plants producing significant energy for export in addition to its primary function of wastewater treatment.

Samela, Daniel A.

330

Mass flows of perfluorinated compounds (PFCs) in central wastewater treatment plants of industrial zones in Thailand  

Microsoft Academic Search

Perfluorinated compounds (PFCs) are fully fluorinated organic compounds, which have been used in many industrial processes and have been detected in wastewater and sludge from municipal wastewater treatment plants (WWTPs) around the world. This study focused on the occurrences of PFCs and PFCs mass flows in the industrial wastewater treatment plants, which reported to be the important sources of PFCs.

Chinagarn Kunacheva; Shuhei Tanaka; Shigeo Fujii; Suwanna Kitpati Boontanon; Chanatip Musirat; Thana Wongwattana; Binaya Raj Shivakoti

2011-01-01

331

Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks.  

PubMed

The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In activated sludge systems, accurate estimation of the solids in the underflow stream will facilitate the calibration process and can lead to correct estimates of particularly kinetic parameters related to biomass growth. Using principles of compaction and consolidation, as in soil mechanics, a dynamic model of the sludge consolidation processes taking place in the secondary settling tanks is developed and incorporated to the commonly used double exponential settling model. The modified double exponential model is calibrated and validated using data obtained from a full-scale wastewater treatment plant. Good agreement between predicted and measured data confirmed the validity of the modified model. PMID:19280899

Abusam, A; Keesman, K J

2009-01-01

332

Treatment and Reuse of Sludge  

Microsoft Academic Search

\\u000a Almost all over the world, the production of sewage sludge rises due to increased population, industrialization and urbanization.\\u000a Treatment and disposal of sewage sludge is an expensive and environmentally challenging task, problems arising mainly from\\u000a lack of social acceptability, high treatment costs, human and environmental health risks associated with treatment and lack\\u000a of sustainable disposal options. Currently the most widely

Maria Fuerhacker; Tadele Measho Haile

333

Pharmaceutical chemicals and endocrine disrupters in municipal wastewater in Tokyo and their removal during activated sludge treatment.  

PubMed

We measured six acidic analgesics or anti-inflammatories (aspirin, ibuprofen, naproxen, ketoprofen, fenoprofen, mefenamic acid), two phenolic antiseptics (thymol, triclosan), four amide pharmaceuticals (propyphenazone, crotamiton, carbamazepine, diethyltoluamide), three phenolic endocrine disrupting chemicals (nonylphenol, octylphenol, bisphenol A), and three natural estrogens (17beta-estradiol, estrone, estriol) in 24-h composite samples of influents and secondary effluents collected seasonally from five municipal sewage treatment plants in Tokyo. Aspirin was most abundant in the influent, with an average concentration of 7300 ng/L (n = 16), followed by crotamiton (921 ng/L), ibuprofen (669 ng/L), triclosan (511 ng/L), and diethyltoluamide (503 ng/L). These concentrations were 1 order of magnitude lower than those reported in the USA and Europe. This can be ascribed to lower consumption of the pharmaceuticals in Japan. Aspirin, ibuprofen, and thymol were removed efficiently during primary + secondary treatment (> 90% efficiency). On the other hand, amide-type pharmaceuticals, ketoprofen, and naproxen showed poor removal (< 50% efficiency), which is probably due to their lower hydrophobicity (logKow < 3). Because of the persistence of crotamiton during secondary treatment, crotamiton was most abundant among the target pharmaceuticals in the effluent. This is the first paper to report ubiquitous occurrence of crotamiton, a scabicide, in sewage. Because crotamiton is used worldwide and it is persistent during secondary treatment, it is a promising molecular marker of sewage and secondary effluent. PMID:16938339

Nakada, Norihide; Tanishima, Toshikatsu; Shinohara, Hiroyuki; Kiri, Kentaro; Takada, Hideshige

2006-10-01

334

Nitrate content of lettuce (Lactuca sativa L.) after fertilization with sewage sludge and irrigation with treated wastewater.  

PubMed

A romaine-type lettuce (Lactuca sativa L.) was cultivated over three crop seasons (spring 2005, spring 2006 and autumn-winter 2006) in six 36 m(2) plots in Alcázar de San Juan, Spain. A drip irrigation system was used to water all plots: five plots with drinking water and one plot with wastewater from the activated sludge system of a wastewater treatment plant (WWTP). One drinking water-irrigated plot was not fertilized (control). Five different treatments were applied to the soil: three organic mixtures (sewage sludge, sewage sludge mixed with pine bark and municipal solid waste with composted sludge) and a conventional fertilizer were applied to the four plots irrigated with drinking water. The last plot was irrigated with treated wastewater. The treatments were tested for their effect on plant growth and nitrate concentration in vegetable tissue. An increase in fresh weight in the lettuce was linked to the dosage of sewage sludge. The highest nitrate level was observed in the sewage sludge treatment in all crops and seasons, although, in general, all values were below the maximum limits established by the European Commission for nitrate content in fresh romaine lettuce. In the third crop season, a significant increase in nitrate content was observed in lettuce from organic treatments. Nitrate concentration in lettuce from irrigated treated wastewater was higher than control, although significant differences were not found. PMID:19680887

Castro, E; Mañas, M P; De Las Heras, J

2009-02-01

335

Wastewater and sludge control-technology options for synfuels industries  

SciTech Connect

The options examined were those of zero discharge, partial water reuse with restricted discharge of treated effluents, and unrestricted discharge of treated effluents. Analysis of cost data and performance-analyses data for several candidate secondary-wastewater-treatment unit processes indicated that combined activated-sludge/powdered-activated-carbon (AS/PAC) treatment incorporating wet-air-oxidation carbon regeneration is the most cost-effective control technology available for the removal of organic material from slagging, fixed-bed process wastewaters. Bench-scale treatability and organic-constituent removal studies conducted on process quench waters from a pilot-scale, slagging, fixed-bed gasifer using lignite as feedstock indicated that solvent extraction followed by AS/PAC treatment reduces levels of extractable and chromatographable organics to less than 1 ..mu..g/L in the final effluent. Levels of conventional pollutants also were effectively reduced by AS/PAC to the minimum water-quality standards for most receiving waters. The most favored and most cost-effective treatment option is unrestricted discharge of treated effluents with ultimate disposal of biosludges and landfilling of gasifier ash and slag. This option requires a capital expenditure of $8,260,000 and an annual net operating cost of $2,869,000 in 1978 dollars, exclusive of slag disposal. The net energy requirement of 19.6 x 10/sup 6/ kWh/year, or 15.3 kWh/1000 gal treated, is less than 6% of the equivalent energy demand associated with the zero-discharge option.

Castaldi, F.J.; Harrison, W.; Ford, D.L.

1981-02-01

336

Potential fertilizing properties of sewage sludge treated in the sludge treatment reed beds (STRB).  

PubMed

In previous research the fertilizer value of sludge from reed beds was evaluated based on the sampling sludge on different depths from four Danish sludge treatment reed beds (STRB) after long periods of stabilization. The dewatering efficiency of sewage sludge in the STRB is comparable to mechanical dewatering. The long-term stabilization of sewage sludge progressively decreases the concentration of organic matter due to the process of humification. The aim of the work was to determine the changes of organic matter concentration, nutrients concentrations as well as speciation of selected heavy metals (Cd, Pb, Ni, Cr, Cu and Zn) in vertical profile of the sewage sludge stabilized in the STRB for 7-15 years. The analyzed sewage sludge was collected from the STRB treating sludge from four municipal wastewater treatment plants located in Denmark serving from 9,000 to 40,000 person equivalent. Analyzed heavy metals (except for Zn) were mostly bound with the most stable - residual - fraction. The most stable metals were Pb and Cr, where the share of the residual fraction exceeded 80.0%. The most mobile metal was Zn, where the share of the mobile fractions (calculated as the sum of I, II and III fractions) exceeded 85.0%. The high concentration of nitrogen and phosphorus is the decisive factor in the high valuation of sludge stabilized in the STRB as fertilizer. PMID:24056442

Ko?ecka, Katarzyna; Obarska-Pempkowiak, Hanna

2013-01-01

337

Increased biogas production in a wastewater treatment plant by anaerobic co-digestion of fruit and vegetable waste and sewer sludge - a full scale study.  

PubMed

Anaerobic digestion is a well established technology for the reduction of organic matter and stabilization of wastewater. Biogas, a mixture of methane and carbon dioxide, is produced as a useful by-product of the process. Current solid waste management at the city of Prince George is focused on disposal of waste and not on energy recovery. Co-digestion of fresh fruit and vegetable waste with sewer sludge can improve biogas yield by increasing the load of biodegradable material. A six week full-scale project co-digesting almost 15,000 kg of supermarket waste was completed. Average daily biogas production was found to be significantly higher than in previous years. Digester operation remained stable over the course of the study as indicated by the consistently low volatile acids-to-alkalinity ratio. Undigested organic material was visible in centrifuged sludge suggesting that the waste should have been added to the primary digester to prevent short circuiting and to increase the hydraulic retention time of the freshly added waste. PMID:22020478

Park, Nathan D; Thring, Ronald W; Garton, Randy P; Rutherford, Michael P; Helle, Steve S

2011-01-01

338

Screening wastewater for toxicity to activated sludge  

SciTech Connect

Several toxicity tests were compared to define their utility for prediction of toxicity to activated sludge. The tests included: (1) oxygen uptake rates in batch tests with activated sludge, (2) adenosine triphosphate (ATP) measurements in the same batch tests, (3) Warburg respirometer studies with activated sludge, and (4) a luminescent bacteria test (Microtox/sup TM/). An evaluation of the toxicity tests was made with several toxicants; nickel (II), mercury (II), 2,4-dichlorophenol (DCP) and 4,6-dinitro-o-cresol (DNOC). Because of differences in toxic mechanism, some of the toxicants produced greater toxic effects in some tests than in other tests. The ATP levels decreased significant when uncouplers of oxidative phosphorylation were studied (DCP and DNOC). Several procedures for measuring ATP were investigated and were found to be unsatisfactory when applied to activated sludge. A new method for extraction of ATP, which incorporated a sonic bath and trichloroacetic acid, was developed. The improved ATP method was used in the toxicity tests and for the additional studies. Current practice in environmental engineering relies on volatile suspended solids (VSS) as a measure of active biomass in activated sludge. After an improved ATP procedure was developed, ATP was investigated for estimation of active biomass. The fate of DCP in the toxicity tests was studied and an adsorptive mechanism was proposed that was based on membrane solubility. This mechanism explained the fate of DCP in the toxicity tests and is useful for understanding the fate of DCP in activated sludge.

Schneider, C.G.

1987-01-01

339

SLUDGE TREATMENT AND DISPOSAL  

EPA Science Inventory

The purpose of this manual is to present a contemporary review of sludge processing technology and the specific procedures to be considered, modified, and applied to meet unique conditions. he manual emphasizes the operational considerations and interrelationships of the various ...

340

Activated sludge systems removal efficiency of veterinary pharmaceuticals from slaughterhouse wastewater.  

PubMed

The knowledge on the efficiency of wastewater treatment plants (WWTPs) from animal food production industry for the removal of both hormones and antibiotics of veterinary application is still very limited. These compounds have already been reported in different environmental compartments at levels that could have potential impacts on the ecosystems. This work aimed to evaluate the role of activated sludge in the removal of commonly used veterinary drugs, enrofloxacin (ENR), tetracycline (TET), and ceftiofur, from wastewater during a conventional treatment process. For that, a series of laboratory-controlled experiments using activated sludge were carried out in batch reactors. Sludge reactors with 100 ?g/L initial drug charge presented removal rates of 68 % for ENR and 77 % for TET from the aqueous phase. Results indicated that sorption to sludge and to the wastewater organic matter was responsible for a significant percentage of drugs removal. Nevertheless, these removal rates still result in considerable concentrations in the aqueous phase that will pass through the WWTP to the receiving environment. Measuring only the dissolved fraction of pharmaceuticals in the WWTP effluents may underestimate the loading and risks to the aquatic environment. PMID:23740304

Carvalho, Pedro N; Pirra, António; Basto, M Clara P; Almeida, C Marisa R

2013-12-01

341

Occurrence of selected polybrominated diphenyl ethers and 2,2',4,4',5,5'-hexabromobiphenyl (BB-153) in sewage sludge and effluent samples of a wastewater-treatment plant in Cape Town, South Africa.  

PubMed

The reuse of treated effluent from wastewater treatment plants (WWTPs) as alternative water source for sport-field or landscape irrigation, agricultural, and other industrial purposes is growing significantly. Similarly, the application of treated sludge (biosolid) to agricultural soils is now being considered globally as the most economic means of sludge disposal. However, the presence of emerging organic contaminants in these matrices, including polybrominated diphenyl ethers (PBDEs), which are potential endocrine disruptors, portends a high health risk to humans and the environment in general. In this study, effluent and sewage sludge samples collected from a WWTP were analysed for some selected PBDE congeners (BDE congeners 28, 47, 99 100 153 154 183, and 209) as well as BB-153 using a high-capillary gas chromatograph equipped with an electron capture detector. The sum of the eight PBDE congeners ranged from 369 to 4370, 19.2 to 2640, and 90.4 to 15,100 ng/l for raw water, secondary effluent, and final effluent, respectively. A similar result was observed for sewage sludge samples, which ranged between 13.1 and 652 ng/g dry weight (dw). The results obtained for BB-153 were generally lower compared with those found for most PBDE congeners. These ranged from ND to 18.4 ng/l and ND to 9.97 ng/g dw for effluents and sewage sludge, respectively. In both matrices, BDE 47 and 209 congeners were found to contribute significantly to the overall sum of PBDEs. The reuse of the treated effluent, particularly for agricultural purposes, could enhance the possibility of these contaminants entering into the food chain, thus causing undesirable health problems in exposed subjects. PMID:22002787

Daso, Adegbenro P; Fatoki, Olalekan S; Odendaal, James P; Olujimi, Olanrewaju O

2012-04-01

342

Deployable Wastewater Treatment Technology Evaluation.  

National Technical Information Service (NTIS)

AFRL/MLQD is expanding the Deployable Waste Disposal System to include bare base wastewater treatment. The goal of AFRL/MLQD is for the deployable wastewater treatment system to be integrated into a waste treatment system that will treat both solid and aq...

E. N. Coppola J. Rine

2002-01-01

343

ORGANIC CHEMICAL FATE PREDICTION IN ACTIVATED SLUDGE TREATMENT PROCESSES  

EPA Science Inventory

The report describes results from a broadly-based effort to determine the feasibility of predicting the fates of organic chemicals in diffused air, activated sludge wastewater treatment processes. The three conversion/removal mechanisms emphasized in the work were stripping, sorp...

344

Treatment of Recycle Streams from Thermal Sludge Conditioning.  

National Technical Information Service (NTIS)

The thermal conditioning and dewatering of activated sludges in wastewater treatment plants results in decant and filtrate streams that are high in organic matter. Although the volume of the recycle flow is small, the high strength may add as much as 20% ...

R. R. Dague

1983-01-01

345

Extracellular polymeric substances (EPS) producing bacterial strains of municipal wastewater sludge: isolation, molecular identification, EPS characterization and performance for sludge settling and dewatering.  

PubMed

Wastewater treatment plants often face the problems of sludge settling mainly due to sludge bulking. Generally, synthetic organic polymer and/or inorganic coagulants (ferric chloride, alum and quick lime) are used for sludge settling. These chemicals are very expensive and further pollute the environment. Whereas, the bioflocculants are environment friendly and may be used to flocculate the sludge. Extracellular polymeric substances (EPS) produced by sludge microorganisms play a definite role in sludge flocculation. In this study, 25 EPS producing strains were isolated from municipal wastewater treatment plant. Microorganisms were selected based on EPS production properties on solid agar medium. Three types of EPS (slime, capsular and bacterial broth mixture of both slime and capsular) were harvested and their characteristics were studied. EPS concentration (dry weight), viscosity and their charge (using a Zetaphoremeter) were also measured. Bioflocculability of obtained EPS was evaluated by measuring the kaolin clay flocculation activity. Six bacterial strains (BS2, BS8, BS9, BS11, BS15 and BS25) were selected based on the kaolin clay flocculation. The slime EPS was better for bioflocculation than capsular EPS and bacterial broth. Therefore, extracted slime EPS (partially purified) from six bacterial strains was studied in terms of sludge settling [sludge volume index (SVI)] and dewatering [capillary suction time (CST)]. Biopolymers produced by individual strains substantially improved dewaterability. The extracted slime EPS from six different strains were partially characterized. PMID:20122709

Bala Subramanian, S; Yan, S; Tyagi, R D; Surampalli, R Y

2010-04-01

346

Anaerobic Treatment of Actual Domestic Wastewater with EGSB Reactor at Ambient Temperature  

Microsoft Academic Search

To assess the feasibility of actual domestic wastewater treatment by an expanded granular sludge bed (EGSB) reactor at ambient temperature, the startup and stable operation performance of an EGSB reactor seeded with digestion sludge treating actual domestic wastewater was monitored in the range of 13~25degC. The results showed that there was no adaptive stage to treat actual domestic wastewater using

Dong Chunjuan; Liu Xiao; Chen Suyun; Wang Yanxia; Zhao Qingliang; Lv Bingnan

2009-01-01

347

EPA (ENVIRONMENTAL PROTECTION AGENCY) DESIGN INFORMATION REPORT: SIDESTREAMS IN WASTEWATER TREATMENT PLANTS  

EPA Science Inventory

Performance problems at publicly-owned treatment works are often attributed to the recycling of sidestreams generated in the wastewater treatment and sludge handling systems. Although the volumes of these sidestreams are generally small compared to plant influent flows, sidestrea...

348

Wastewater reclamation by advanced treatment of secondary effluents  

Microsoft Academic Search

The objectives of this study were the investigation of the performance of an advanced treatment system, for the reclamation of secondary municipal effluents, and the study of the environmental quality of treated effluents. The secondary effluents from a conventional activated sludge process were fed to an advanced wastewater treatment system, consisting of a moving-bed sand filter, a granular activated carbon

M. Petala; V. Tsiridis; P. Samaras; A. Zouboulis; G. P. Sakellaropoulos

2006-01-01

349

DENSITY LEVELS OF PATHOGENIC ORGANISMS IN MUNICIPAL WASTEWATER SLUDGE: A LITERATURE REVIEW  

EPA Science Inventory

This report presents a critical review of the literature from laboratory and full scale studies regarding density levels of indicator and pathogenic organisms in municipal wastewater sludges and septage. The effectiveness of conventional municipal sludge stabilization processes (...

350

NEOS Server Usage in Wastewater Treatment Cost Minimization  

Microsoft Academic Search

\\u000a This paper describes the optimal design and operation of an activated sludge system in wastewater treatment plants. The optimization\\u000a problem is represented as a smooth programming problem with linear and nonlinear equality and inequality constraints, in which\\u000a the objective is to minimize the total cost required to design and operate the activated sludge system under imposed effluent\\u000a quality laws. We

I. A. C. P. Espírito-santo; Edite M. G. P. Fernandes; M. M. Araújo; E. C. Ferreira

2005-01-01

351

Ultrasonic reduction of excess sludge from activated sludge system II: urban sewage treatment.  

PubMed

Previous study showed that sonication was effective to reduce waste activated sludge (WAS) using artificial wastewater. This paper confirms the viability and evaluates the performance of this method in practical wastewater treatment using urban sewage without temperature control. The results showed that sonication significantly lowered the WAS and biomass synthesis, and greatly enhanced the mineralization of sewage organics. The optimal specific energy for sludge lysis was 20.0k Wh/kg DS. Further energy-increase had little benefit on WAS reduction. When the specific energy was 20.0kWh/kgDS and the sludge recycle ratio was 0.007, the WAS decreased by 54%, the biomass synthesis abated by 59%, and the sewage mineralization ratio increased from 31% to 58%. The effluent COD and nitrogen were stable but phosphorus was higher than that of the control bioreactor. The COD removal was lower but the WAS reduction was higher for urban sewage than for artificial wastewater. The accumulation pattern of heavy metals in sludge was greatly alternated by the sonication-cryptic growth; and different metals behaved differently. The sludge Ni concentration increased by 141% while As decreased by 53%. PMID:18926629

Zhang, Guangming; He, Junguo; Zhang, Panyue; Zhang, Jie

2009-05-30

352

Purification of cork processing wastewaters by ozone, by activated sludge, and by their two sequential applications  

Microsoft Academic Search

Wastewaters generated in the cork processing industry were treated in continuous reactors by means of single treatments separately—a chemical ozonation and an activated sludge system—and then by both sequential processes—ozonation followed by aerobic degradation, and aerobic degradation followed by ozonation. The removals obtained in the ozonation alone were 12–54%, 65–81%, and 55–89% for the COD, total phenolics, and absorbance at

F. Javier Benitez; Juan L. Acero; Juan Garcia; Ana I. Leal

2003-01-01

353

Polyelectrolyte conditioning for iron-hydroxide-containing sludge produced from electroflocculation of fermentation wastewater.  

PubMed

The purpose of this study is to investigate the application of chemical conditioning method for the post-electroflocculation wastewater sludge treatment with polyelectrolytes of varying ionic characters, namely anionic, cationic and nonionic flocculating agents. Electroflocculation, a combination of the processes of electroflotation and electroprecipitation, was found effective to remove the organic and color components in monosodium glutamate fermentation wastewater. The settleability and dewaterability of the separated sludge, containing 15-20% of iron hydroxides, increased 35% and 60% due to polymer conditioning through a jar-test apparatus. The influence of shear conditions and polymer dose on the floc size, zeta potential, filterability and dewatering performance, and shear resistance of sludges was investigated. Experimental results showed that the anionic polymer acts as a better flocculating agent than both cationic and nonionic polymers, and the optimal polymer doses fall between 4.0 and 10.0 mg/g Fe sludge under corresponding shear rates of 200 300 rpm. This study also indicated that both charge neutralization and polymer bridging mechanisms operate in the sludge conditioning process. PMID:15328692

Chen, Wen-Jang; Chen, Tson-Nan; Cheng, Yang-Chu

2002-08-01

354

PAPERMILL WASTEWATER TREATMENT BY MICROSTRAINING  

EPA Science Inventory

An original treatment system was designed, constructed, and operated for removal of suspended solids, turbidity, color, and BOD from the wastewaters of two paper mills which produce technical and other fine papers. The treatment process involves coagulation and flocculation follo...

355

Wastewater treatment with microalgae  

SciTech Connect

In locations where total solar energy inputs average 400 langeleys or more, microscopic algae, grown in properly designed ponds, can contribute significantly and economically to wastewater treatment. While growing, microalgae produce an abundance of oxygen for microbial and biochemical oxidation of organics and other reduced compounds and for odor control. Microalgae also accelerate the inactivation of disease bacteria and parasitic ova by increasing water temperature and pH. Microalgae remove significant amounts of nitrogen and phosphorus and adsorb most polyvalent metals, including those that are toxic. After growth in properly designed paddle wheel mixed high rate ponds, microalgae settle readily, leaving a supernatant free of most pollutants. Such effluents are suitable for irrigation of ornamental plants, crops not eaten raw, aquaculture, and grounwater recharge. The settled and concentrated microalgae may be used for fertilizer, for fermentation to methane, or, assuming no toxicity, for fish, bivalve, or animal feed.

Oswald, W.J. (Univ. of California, Berkeley (United States))

1992-01-01

356

Quick Startup of EGSB Reactor Seeded with Anaerobic Digestion Sludge for the Treatment of Actual Domestic Sewage under Ambient Temperature  

Microsoft Academic Search

To obtain the rapid startup of EGSB reactor seeded with anaerobic digestion sludge for the treatment of actual domestic wastewater under ambient temperature, two startup methods i.e. A and B were tried out at 25°C. For method A, reactor A (RA) was fed with brewery wastewater to incubate granular sludge and then treated domestic sewage, for method B, reactor B

Dong Chunjuan; Li Qingwei; Geng Zhaoyu; Wang Haihui; Wang Zengzhang

2010-01-01

357

Sludge.  

ERIC Educational Resources Information Center

Cites a recycling success story involving sludge production from wastewater and transformation into an effective plant fertilizer. Discusses related concerns such as dealing with pollutants like heavy metals and PCBs often found in sludge. Provides an example of an application of sludge produced in Chicago to an area reclamation site. (MCO)

Tenenbaum, David

1992-01-01

358

Characteristics and performance of aerobic granular sludge treating rubber wastewater at different hydraulic retention time.  

PubMed

The influence of hydraulic retention time (HRT, 24, 12, and 6h) on the physical characteristics of granules and performance of a sequencing batch reactor (SBR) treating rubber wastewater was investigated. Results showed larger granular sludge formation at HRT of 6h with a mean size of 2.0±0.1mm, sludge volume index of 20.1mLg(-1), settling velocity of 61mh(-1), density of 78.2gL(-1) and integrity coefficient of 9.54. Scanning electron microscope analyses revealed different morphology of microorganisms and structural features of granules when operated at various HRT. The results also demonstrated that up to 98.4% COD reduction was achieved when the reactor was operated at low HRT (6h). Around 92.7% and 89.5% removal efficiency was noted for ammonia and total nitrogen in the granular SBR system during the treatment of rubber wastewater. PMID:24704837

Rosman, Noor Hasyimah; Nor Anuar, Aznah; Chelliapan, Shreeshivadasan; Md Din, Mohd Fadhil; Ujang, Zaini

2014-06-01

359

Biodegradation of wastewater pollutants by activated sludge encapsulated inside calcium-alginate beads in a tubular packed bed reactor.  

PubMed

The wastewater treatment plants produce large quantities of biomass (sludge) that require about one-third of the total inversion and operation plant costs for their treatment. By the microorganisms immobilization it is possible to handle high cell concentration in the reactor, increasing its efficiency, reducing the loss of biomass and the wash out is avoided. Moreover, there is no cell growth then the sludge production is reduced. In this study, the COD removal and VSS variation were modeled in a tubular reactor with activated sludge immobilized in Ca-alginate. Moreover, two aspects that are commonly not considered in the performance of the actual reactors of this kind were introduced; the performance in non-steady state and the dispersion effect. The model was calibrated with an actual wastewater taken out from a Mexican wastewater treatment plant. The results of the performance of the tubular bioreactor at different scenarios (i.e., different residence time and VSS in the reactor) are presented. With longer residence times and higher VSS concentration in the Ca-alginate beads in the tubular bioreactor it is possible to increase the time operation of the bioreactor and to treat higher volumes of wastewater. During the process, the sludge generation was drastically reduced and it is possible to remove nitrogen form the wastewater making this process more attractive. PMID:19340591

Sergio, A Martinez D; Bustos, T Yaneth

2009-09-01

360

Nutrient Removal in Wastewater Treatment  

ERIC Educational Resources Information Center

Discusses the sources and effects of nutrients in wastewater, and the methods of their removal in wastewater treatment. In order to conserve water resources and eliminate the cost of nutrient removal, treated effluent should be used wherever possible for irrigation, since it contains all the ingredients for proper plant growth. (JR)

Shah, Kanti L.

1973-01-01

361

Design more flexibility into wastewater treatment  

SciTech Connect

Several case histories illustrates how to design a refinery wastewater treatment system (WWTS). The heart of WWTS, the biological oxidation (BIOX) process, is the main focus. The design case history shows how to calculate BIOX parameters such as system flow, hydraulic retention time, sludge age, destruction/removal efficiency, reactor loading, etc. Tighter control on equipment size prevents overdesign and minimizes capital and operating costs. A BIOX system that is too large can cause as many problems as one that is too small. Improved WWTSs specification allows cost-effective operations at extreme flow and contaminant conditions. The paper describes the complex and variable scheme, WWTS design concepts, waste water biodegradability, destruction/removal efficiency, food-to-microorganisms, mixed liquor suspended solids, hydraulic retention time, sludge age, BIOX reactor loading, aeration, temperature, clarifier, discharge permit limits, operating diagram, operability review, and three case histories.

Capps, R.W. (Pace Consultants, Inc., Houston, TX (United States)); Matelli, G.N.; Bradford, M.L. (Jacobs Engineering Group, Inc., Houston, TX (United States))

1993-12-01

362

SURVEY OF A WASTEWATER TREATMENT PLANT MICROFAUNA BY IMAGE ANALYSIS  

Microsoft Academic Search

The microfauna present in the activated sludge of a wastewater treatment plant is mainly composed by bacteria, protozoa and metazoa. The protozoan species are quite sensitive to physical, chemical and operational processes making them, thus, precious indicators of the state of the plant. Several authors already established relationships between the predominance of certain species or group and some parameters of

A. L. Amaral; M. da Motta; M. N. Pons; H. Vivier; M. Mota; E. C. Ferreira

363

SAFETY MANUAL FOR WASTEWATER TREATMENT WITH OXYGEN AERATION  

EPA Science Inventory

This safety manual provides design, operating, and safety personnel of municipal wastewater treatment plants which use oxygen aeration of activated sludge systems with the knowledge to prevent hazards due to the interaction of the oxygen with combustibles and other hazardous mate...

364

Perfluoroalkyl compounds in Danish wastewater treatment plants and aquatic environments  

Microsoft Academic Search

This study reports the results of a screening survey of perfluoroalkyl compounds (PFCs) in the Danish environment. The study included point sources (municipal and industrial wastewater treatment plants and landfill sites) and the marine and freshwater environments. Effluent and influent water and sewage sludge were analysed for point sources. Sediment, blue mussels (Mytilus edulis) and liver from plaice (Pleuronectes platessa),

R. Bossi; J. Strand; O. Sortkjær; M. M. Larsen

2008-01-01

365

Successful Treatment of Low PAH-Contaminated Sewage Sludge in Aerobic Bioreactors (7 pp)  

Microsoft Academic Search

Background, Aims and Scope   Polycyclic Aromatic Hydrocarbons (PAHs) are known for their adverse and cumulative effects at low concentration. In particular,\\u000a the PAHs accumulate in sewage sludge during wastewater treatment, and may thereafter contaminate agricultural soils by spreading\\u000a sludge on land. Therefore, sludge treatment processes constitute the unique opportunity of PAH removal before their release\\u000a in the environment. In this

Eric Trably; Dominique Patureau

2006-01-01

366

RECOMMENDED PRACTICE FOR THE USE OF ELECTROMAGNETIC FLOWMETERS IN WASTEWATER TREATMENT PLANTS  

EPA Science Inventory

Electromagnetic flowmeters that conform to the guidelines described in this document can be used to measure the volumetric flowrate of all liquids and sludges normally encountered in wastewater treatment plants, provided that adequate inspection and maintenance are performed as r...

367

Effects on Toxicity of Volatile Priority Pollutants Added to a Conventional Wastewater Treatment System.  

National Technical Information Service (NTIS)

Static acute, unaerated, toxicity tests using fathead minnows and Daphnia magna and a bacterial toxicity assay, Microtox(TM), were conducted on samples of influent and effluent from two conventional activated sludge pilot wastewater treatment systems. The...

T. W. Neiheisel W. B. Horning A. C. Petrasek V. R. Asberry D. A. Jones

1983-01-01

368

EVALUATION OF THE TWO-ZONE WASTEWATER TREATMENT PROCESS AT NORRISTOWN, PENNSYLVANIA  

EPA Science Inventory

Economic and practical considerations compel today's designers to investigate alternatives to conventional strategies for wastewater treatment systems. One such alternative is the Two-Zone process, a novel activated sludge process which combines the aerobic biological reactor and...

369

Energy autonomy in the wastewater treatment process  

SciTech Connect

Wastewater treatment plants can recover a high percentage of their energy needs by using new techniques in anaerobic digestion through the production and utilization of methane gas. The Acheres Wastewater Treatment Plant outside Paris has a present design capacity of 1.5 x 10/sup 6/ m/sup 3//d (400 mgd) and produces over 70% of its energy needs using this process. Methane gas is used to drive a series of engines that produce compressed air for the biological process and drive generators that produce electricity for use in all phases of the treatment process, equipment, and buildings. Water that cools these engines is also used to maintain optimum sludge temperature during the digestion process. After World War II, a master plan was developed that projects the plant's expansion through five major phases to an ultimate design capacity of 2.7 x 10/sup 6/ m/sup 3//d (715 mgd). To date three phases are in operation, with a total design capacity of 1.5 x 10/sup 6/ m/sup 3//d (400 mgd). Phase IV (6.0 x 10/sup 5/ m/sup 3//d, 160 mgd) is under construction. The article reviews the sludge digestion process used in all three operating phases of the plant.

Bernard, J. (Degremont S. A., Paris, France); DaVia, P.

1980-03-01

370

POTENTIAL HEALTH EFFECTS FROM PERSISTENT ORGANICS IN WASTEWATER AND SLUDGES USED FOR LAND APPLICATION  

EPA Science Inventory

The potential health problems associated with the presence of persistent organic chemicals in wastewater and sludge, when applied to agricultural lands, are reviewed. The type and amounts of organic chemicals present in wastewater and sludge, their fate on land, and available con...

371

SLUDGE DEWATERING AND DRYING ON SAND BEDS  

EPA Science Inventory

Dewatering of water and wastewater treatment sludges was examined through mathematical modeling and experimental work. The various components of the research include: (1) chemical analyses of water treatment sludges, (2) drainage and drying studies of sludges, (3) a mathematical ...

372

Cheese whey wastewater: characterization and treatment.  

PubMed

Cheese whey wastewater (CWW) is a strong organic and saline effluent whose characterization and treatment have not been sufficiently addressed. CWW composition is highly variable due to raw milk used, the fraction of non valorized cheese whey and the amount of cleaning water used. Cheese whey wastewater generation is roughly four times the volume of processed milk. This research tries to conduct an exhaustive compilation of CWW characterization and a comparative study between the different features of CWW, cheese whey (CW), second cheese whey (SCW) and dairy industry effluents. Different CWW existing treatments have also been critically analyzed. The advantages and drawbacks in aerobic/anaerobic processes have been evaluated. The benefits of physicochemical pre-stages (i.e. precipitation, coagulation-flocculation) in biological aerobic systems are assessed. Pre-treatments based on coagulation or basic precipitation might allow the application of aerobic biodegradation treatments with no dilution requirements. Chemical precipitation with lime or NaOH produces a clean wastewater and a sludge rich in organic matter, N and P. Their use in agriculture may lead to the implementation of Zero discharge systems. PMID:23376111

Carvalho, Fátima; Prazeres, Ana R; Rivas, Javier

2013-02-15

373

Utilizing acid mine drainage sludge and coal fly ash for phosphate removal from dairy wastewater.  

PubMed

This study aims to investigate a new and sustainable approach for the reuse of industrial by-products from wastewater treatment. The dairy industry produces huge volumes of wastewater, characterized by high levels of phosphate that can result in eutrophication and degradation of aquatic ecosystems. This study evaluated the application of acid mine drainage (AMD) sludge, coal fly ash, and lignite as low-cost adsorbents for the removal of phosphate from dairy wastewater. Material characterization using X-ray fluorescence, X-ray diffraction, and Brunauer-Emmett-Teller surface area analysis revealed significant amounts of crystalline/amorphous Fe/Al/Si/Ca-based minerals and large surface areas of AMD sludge and fly ash. Batch adsorption isotherms were best described using the Freundlich model. The Freundlich distribution coefficients were 13.7 mg(0.577) L(0.423) g(-1) and 16.9 mg(0.478) L(0.522) g(-1) for AMD sludge and fly ash, respectively, and the nonlinearity constants suggested favourable adsorption for column applications. The breakthrough curves of fixed-bed columns, containing greater than 10 wt% of the waste materials (individual or composite blends) mixed with sand, indicated that phosphate breakthrough did not occur within 100 pore volumes while the cumulative removal was 522 and 490 mg kg(-1) at 10 wt% AMD sludge and 10 wt% fly ash, respectively. By contrast, lignite exhibited negligible phosphate adsorption, possibly due to small amounts of inorganic minerals suitable for phosphate complexation and limited surface area. The results suggest that both AMD sludge and fly ash were potentially effective adsorbents if employed individually at a ratio of 10 wt% or above for column application. PMID:24617077

Wang, Y R; Tsang, Daniel C W; Olds, William E; Weber, Paul A

2013-01-01

374

Energy from municipal waste: assessment of energy conservation and recovery in municipal wastewater treatment  

SciTech Connect

This document provides a qualitative report on the status of a program for energy conservation in wastewater treatment. Analyzing the nation's energy requirements for wastewater treatment by process has shown that the wastewater- and sludge-stabilization processes accounted for more than 56% of the energy used for wastewater treatment in 1978. Advanced processes are projected to have the largest increase in energy of all treatment processes between 1978 and the year 2000. To promote energy conservation in wastewater treatment, DOE has sponsored a number of projects (either wholly or in part), including the following: demonstration of the anaerobic upflow (ANFLOW) bioreactor at Knoxville, Tenn.; assessment of digester-gas production and use in anaerobic-digestion facilities; study of the enhancement of anaerobic digestion by carbon addition; demonstration of water-hyacinth wastewater-treatment (WHWT) at Lake Buena Vista, Florida; and demonstration of unheated anaerobic contact stabilization (UACS) of sludge. These programs are described. 19 references, 22 figures, 29 tables.

Pierson, F.W.; Pearson, C.V.

1984-10-01

375

Application of Sludges and Wastewaters on Agricultural Land: A Planning and Educational Guide, MCD-35. Research Bulletin 1090.  

ERIC Educational Resources Information Center

This report addresses the application of agricultural processing wastes, industrial and municipal wastes on agricultural land as both a waste management and resource recovery and reuse practice. The document emphasizes the treatment and beneficial utilization of sludge and wastewater as opposed to waste disposal. These objectives are achieved…

Knezek, Bernard D., Ed.; Miller, Robert H., Ed.

376

AMMONIUM-CARBONATE LEACHING OF METAL VALUES FROM WATER-TREATMENT SLUDGES  

EPA Science Inventory

This project was undertaken to explore and develop processes based on ammoniacal leaching to recover metal values from metal-finishing wastewater treatment sludges. The objective was to eliminate or to reduce sufficiently the heavy metal content of the sludge so that it would no ...

377

REVIEW OF TECHNIQUES FOR TREATMENT AND DISPOSAL OF PHOSPHORUS-LADEN CHEMICAL SLUDGES  

EPA Science Inventory

The report summarizes the effects of phosphorus removal by chemical addition on sludge handling and disposal options at full-scale wastewater treatment plants. American and Canadian plants which generate phosphorus-laden chemical sludges were surveyed by questionnaire, and 174 re...

378

Techno-economic analysis of wastewater sludge gasification: A decentralized urban perspective.  

PubMed

The successful management of wastewater sludge for small-scale, urban wastewater treatment plants, (WWTPs), faces several financial and environmental challenges. Common management strategies stabilize sludge for land disposal by microbial processes or heat. Such approaches require large footprint processing facilities or high energy costs. A new approach considers converting sludge to fuel which can be used to produce electricity on-site. This work evaluated several thermochemical conversion (TCC) technologies from the perspective of small urban WWTPs. Among TCC technologies, air-blown gasification was found to be the most suitable approach. A gasification-based generating system was designed and simulated in ASPEN Plus® to determine net electrical and thermal outputs. A technical analysis determined that such a system can be built using currently available technologies. Air-blown gasification was found to convert sludge to electricity with an efficiency greater than 17%, about triple the efficiency of electricity generation using anaerobic digester gas. This level of electricity production can offset up to 1/3 of the electrical demands of a typical WWTP. Finally, an economic analysis concluded that a gasification-based power system can be economically feasible for WWTPs with raw sewage flows above 0.093m(3)/s (2.1 million gallons per day), providing a profit of up to $3.5 million over an alternative, thermal drying and landfill disposal. PMID:24727699

Lumley, Nicholas P G; Ramey, Dotti F; Prieto, Ana L; Braun, Robert J; Cath, Tzahi Y; Porter, Jason M

2014-06-01

379

Survey of Protozoa and Metazoa populations in wastewater treatment plants by image analysis and discriminant analysis  

Microsoft Academic Search

SUMMARY The biota present in the activated sludge of a wastewater treatment plant are mainly composed of bacteria, Protozoa and Metazoa. The Protozoa and Metazoa species are important micro-organisms taking part in the ecosystem balance in wastewater treatment plants and are quite sensitive to physical, chemical and operational processes. Several authors have established relationships between the predominance of certain species

A. L. Amaral; M. da Motta; M. N. Pons; H. Vivier; N. Roche; M. Mota; E. C. Ferreira

2004-01-01

380

Granulation of biomass in thermophilic upflow anaerobic sludge blanket reactors treating acidified wastewaters  

Microsoft Academic Search

The development of granular sludge in thermophilic (55 degrees C) upflow anaerobic sludge blanket reactors was investigated. Acetate and a mixture of acetate and butyrate were used as substrates, serving as models for acidified wastewaters. Granular sludge with either Methanothrix or Methanosarcina as the predominant acetate utilizing methanogen was cultivated by allowing the loading rate to increase whenever the acetate

W. M. Wiegant; A. W. A. de Man

1986-01-01

381

Survival of Ascaris suum eggs in ammonia-treated wastewater sludges  

Microsoft Academic Search

The use of wastewater sludges in agriculture is widespread throughout the world. The nutrients (especially organic matter and minerals) present in sludges can reduce or completely eliminate the need for commercial fertilizers. However, the disposal or reuse of inadequately treated sewage sludge poses a serious health risk to humans and animals. The aim of this study was to evaluate a

Roberta Ghiglietti; Claudio Genchi; Luigi Di Matteo; Enrico Calcaterra; Antonio Colombi

1997-01-01

382

Identification of wastewater sludge characteristics to predict critical flux for membrane bioreactor processes  

Microsoft Academic Search

The effects of sludge characteristics on critical flux were examined using a submerged membrane bioreactor pilot plant operated under different process conditions to treat municipal wastewater. The sludge in the membrane tank was characterized by measuring colloidal particle concentration, extracellular polymeric substances (EPS), mixed liquor suspended solids (MLSS), temperature, time to filter (TTF) and diluted sludge volume index (DSVI). The

Fengshen Fan; Hongde Zhou; Hadi Husain

2006-01-01

383

Design concepts for biological treatment of industrial wastewater  

SciTech Connect

Wastewater treatment systems have an operating envelope bounded by upper and lower operating limits. The design criteria should therefore include upper and lower operating limits. Upper limits are generally dictated by the effluent permit, whereas lower limits are the result of design. The design challenge for an industrial wastewater treatment system is to create a process which is capable of responding to extreme variations in flow and pollutant concentration, yet maintain the effluent within permit limitations. Industrial wastewater is contaminated with oil, aromatics, ammonia, phenols, sulfide, and heavy metals. Because the operating loads (flow, pollutant concentration, toxics, pH, and salinity) are largely unpredictable, maximum flexibility and controllability should be incorporated into the design. Since the heart of the wastewater treating system is the biological oxidation process, particular attention should be given to its specifications. A biological oxidation system that is too large can cause as many problems as one that is too small. This paper focuses on design considerations for the activated sludge process for industrial wastewater. Case Study 1 is an example of how to design a grass roots wastewater treatment plant for a new refinery. This design provides for the maximum efficiency and operability within permit limits. However, Case Study 2 is an example of how not to design an industrial wastewater treatment plant. Typically wastewater treatment systems like Case Study 2 are over-designed, which causes many operability problems that lead to permit excursions. 12 refs., 8 figs., 2 tabs.

Capps, R.W. [Pace Consultants, Inc., Houston, TX (United States); Mantelli, G.N.; Bradford, M.L. [Jacobs Engineering Group, Inc., Houston, TX (United States)

1995-02-01

384

UASB\\/EGSB APPLICATIONS FOR INDUSTRIAL WASTEWATER TREATMENT  

Microsoft Academic Search

Installation of the upflow anaerobic sludge bed (UASB) and expanded granular sludge bed (EGSB) for industrial wastewater has grown very rapid by over the past (15-20 years). The UASB (Upflow Anaerobic Sludge Blanket) process and (EGSB) with high liquid and\\/or gas upflow velocities require biomass with excellent settling characteristics. Typically, granular sludge or anaerobic sludge grown on inorganic support is

Medhat M. A. Saleh; Usama F. Mahmood

2003-01-01

385

TREATMENT OF OILY WASTEWATER  

Microsoft Academic Search

\\u000a Oily wastewaters are generated in many industrial processes, such as petroleum refining, petrochemical, food, leather and\\u000a metal finishing. Fats, oils and greases (FOG’s) present in these wastewaters have to be removed before the water can be reused\\u000a in a closed-loop process or discharged into the sewer system or to surface waters. These oily waters are mainly in the form\\u000a of

JOSÉ COCA; GEMMA GUTIÉRREZ; JOSÉ M. BENITO

386

CHLORINATED ORGANIC COMPOUNDS IN DIGESTED, HEAT-CONDITIONED, AND PURIFAX-TREATED SLUDGES  

EPA Science Inventory

Wastewater sludges were stabilized by Purifax treatment, anaerobic digestion and heat conditioning. The processed sludges from the Purifax process at chlorine dosages normally used in processing wastewater sludges contained 2 to > 14 times the total organic chlorine content of th...

387

Sugarcane molasses-based bio-ethanol wastewater treatment by two-phase multi-staged up-flow anaerobic sludge blanket (UASB) combination with up-flow UASB and down-flow hanging sponge.  

PubMed

This study was designed to evaluate a treatment system for high strength wastewater (vinasse) from a sugarcane molasses-based bio-ethanol plant in Thailand. A laboratory-scale two-phase treatment system composed of a sulfate reducing (SR) tank and multi-staged up-flow anaerobic sludge blanket (MS-UASB) reactor was used as the pre-treatment unit. Conventional UASB and down-flow hanging sponge (DHS) reactors were used as the post-treatment unit. The treatment system was operated for 300 days under ambient temperature conditions (24.6-29.6 °C). The hydraulic retention time (HRT) in each unit was kept at 25 h for the two-phase system and 23 h for the UASB&DHS. The influent concentration was allowed to reach up to 15,000 mg chemical oxygen demand (COD)/L. COD removal efficiency (based on influent COD) of the two-phase MS-UASB and the UASB&DHS was 54.9 and 18.7%, respectively. Due to the effective removal of sulfide in the SR tank, the MS-UASB achieved a high methane conversion ratio of up to 97%. In DHS, nitrification occurred at the outside portion of the sponge media while denitrification occurred at the inside. Consequently, 27% of the total nitrogen (TN) was removed. An amount of 32% of residual nitrogen (28 mgN/L) was in the form of nitrate, a better nitrogen state for fertilizer. PMID:24647181

Choeisai, P; Jitkam, N; Silapanoraset, K; Yubolsai, C; Yoochatchaval, W; Yamaguchi, T; Onodera, T; Syutsubo, K

2014-01-01

388

Wastewater Solids Process Technology for Environmental Quality Improvement.  

National Technical Information Service (NTIS)

A review of problems confronted in disposing of sludges from municipal wastewater treatment plants is presented. The quantities and characteristics of these sludges that must be dealt with are enumerated. Waste sludges originating from the activated sludg...

J. E. Smith

1970-01-01

389

Reliability analysis of wastewater treatment plants.  

PubMed

This article presents a reliability analysis of 166 full-scale wastewater treatment plants operating in Brazil. Six different processes have been investigated, comprising septic tank+anaerobic filter, facultative pond, anaerobic pond+facultative pond, activated sludge, upflow anaerobic sludge blanket (UASB) reactors alone and UASB reactors followed by post-treatment. A methodology developed by Niku et al. [1979. Performance of activated sludge process and reliability-based design. J. Water Pollut. Control Assoc., 51(12), 2841-2857] is used for determining the coefficients of reliability (COR), in terms of the compliance of effluent biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and fecal or thermotolerant coliforms (FC) with discharge standards. The design concentrations necessary to meet the prevailing discharge standards and the expected compliance percentages have been calculated from the COR obtained. The results showed that few plants, under the observed operating conditions, would be able to present reliable performances considering the compliance with the analyzed standards. The article also discusses the importance of understanding the lognormal behavior of the data in setting up discharge standards, in interpreting monitoring results and compliance with the legislation. PMID:17897694

Oliveira, Sílvia C; Von Sperling, Marcos

2008-02-01

390

Parameters affecting the formation of perfluoroalkyl acids during wastewater treatment.  

PubMed

This study examined the fate and behaviour of perfluoroalkyl acids (PFAAs) in liquid and solid samples from five different wastewater treatment types: facultative and aerated lagoons, chemically assisted primary treatment, secondary aerobic biological treatment, and advanced biological nutrient removal treatment. To the best of our knowledge, this is the largest data set from a single study available in the literature to date for PFAAs monitoring study in wastewater treatment. Perfluorooctanoic acid (PFOA) was the predominant PFAA in wastewater with levels from 2.2 to 150ng/L (influent) and 1.9 to 140ng/L (effluent). Perfluorooctanesulfonic acid (PFOS) was the predominant compound in primary sludge, waste biological sludge, and treated biosolids with concentrations from 6.4 to 2900ng/g dry weight (dw), 9.7 to 8200ng/gdw, and 2.1 to 17,000ng/gdw, respectively. PFAAs were formed during wastewater treatment and it was dependant on both process temperature and treatment type; with higher rates of formation in biological wastewater treatment plants (WWTPs) operating at longer hydraulic retention times and higher temperatures. PFAA removal by sorption was influenced by different sorption tendencies; median log values of the solid-liquid distribution coefficient estimated from wastewater biological sludge and final effluent were: PFOS (3.73)>PFDA (3.68)>PFNA (3.25)>PFOA (2.49)>PFHxA (1.93). Mass balances confirmed the formation of PFAAs, low PFAA removal by sorption, and high PFAA levels in effluents. PMID:24691135

Guerra, P; Kim, M; Kinsman, L; Ng, T; Alaee, M; Smyth, S A

2014-05-15

391

Nitrification treatment of wastewater  

SciTech Connect

In a two stage activated sludge plant, where in the first stage the major proportion of the organic pollutants is decomposed and in the second stage the decomposition of the residual organic pollutants is conducted in conjunction with nitrification, the nitrifying bacteria are fixed on a low-density, macroporous carrier, e.g., particulate, polyurethane, optionally with activated carbon as well. The second stage can be operated as a mixed activated sludge tank or a biological filter, and in either case, it is possible to avoid a post clarification stage.

Fuchs, U.

1983-11-15

392

Dedicated land disposal of wastewater sludge in south africa: leaching of trace elements and nutrients.  

PubMed

Most of the wastewater treatment facilities in South Africa (80%) dispose of their sewage sludge on dedicated land disposal (DLD) sites. The impact of this practice on the environment is believed to be negative, but very little research has been carried out to determine the extent of the damage to the soil and water resources. Forty wastewater treatment facilities using DLD, with different soil properties, application techniques, metal concentrations and period of sludge application, were studied. Soil and groundwater samples were collected at each of the selected facilities. Three extraction methods (aqua regia, NH4EDTA and NH4NO3) were used and samples were analysed for total N, P and K, pH, organic carbon and their metal content (Cr, Co, Ni, Cu, Zn, Cd, and Pb). Some degree of leaching of the heavy metals (especially Co and Ni) occurred at some of the sampling sites and the average depth of leaching was 100-200 mm. Deeper than 300 mm, the metal concentrations in most soil samples reached background concentrations. Seven of the nine groundwater samples that could be obtained had high NO3 concentrations (> 6 mg L(-1)). Statistical analyses of the data indicate no significant differences between sludge type (wet or dry) and leaching, or age of the disposal sites and leaching. Taking into account the age of the disposal sites, the frequency of sludge application and the metal load of the sludge, the depth of leaching is surprisingly shallow in most soils, in spite of the low soil pH(H2O) and clay content. PMID:17087379

Herselman, J E; Steyn, C E; Snyman, H G

2006-01-01

393

Thermophilic biological nitrogen removal in industrial wastewater treatment.  

PubMed

Nitrification is an integral part of biological nitrogen removal processes and usually the limiting step in wastewater treatment systems. Since nitrification is often considered not feasible at temperatures higher than 40 °C, warm industrial effluents (with operating temperatures higher than 40 °C) need to be cooled down prior to biological treatment, which increases the energy and operating costs of the plants for cooling purposes. This study describes the occurrence of thermophilic biological nitrogen removal activity (nitritation, nitratation, and denitrification) at a temperature as high as 50 °C in an activated sludge wastewater treatment plant treating wastewater from an oil refinery. Using a modified two-step nitrification-two-step denitrification mathematical model extended with the incorporation of double Arrhenius equations, the nitrification (nitrititation and nitratation) and denitrification activities were described including the cease in biomass activity at 55 °C. Fluorescence in situ hybridization (FISH) analyses revealed that Nitrosomonas halotolerant and obligatehalophilic and Nitrosomonas oligotropha (known ammonia-oxidizing organisms) and Nitrospira sublineage II (nitrite-oxidizing organism (NOB)) were observed using the FISH probes applied in this study. In particular, this is the first time that Nitrospira sublineage II, a moderatedly thermophilic NOB, is observed in an engineered full-scale (industrial) wastewater treatment system at temperatures as high as 50 °C. These observations suggest that thermophilic biological nitrogen removal can be attained in wastewater treatment systems, which may further contribute to the optimization of the biological nitrogen removal processes in wastewater treatment systems that treat warm wastewater streams. PMID:23657583

Lopez-Vazquez, C M; Kubare, M; Saroj, D P; Chikamba, C; Schwarz, J; Daims, H; Brdjanovic, D

2014-01-01

394

Nitrification treatment of wastewater  

Microsoft Academic Search

In a two stage activated sludge plant, where in the first stage the major proportion of the organic pollutants is decomposed and in the second stage the decomposition of the residual organic pollutants is conducted in conjunction with nitrification, the nitrifying bacteria are fixed on a low-density, macroporous carrier, e.g., particulate, polyurethane, optionally with activated carbon as well. The second

Fuchs

1983-01-01

395

Development of flexible fibre biofilm reactor for treatment of food processing wastewater.  

PubMed

Biological treatment methods are usually effective and commonly used in the treatment of organic wastewater. However, there are a number of problems for conventional biological treatment methods in treating wastewater from industries such as food processing. For example, microorganisms in the aeration tank in an activated sludge process cannot survive a continuous series of shock loads and the process could become operationally unstable. The associated problem of sludge bulking often occurs when the organic loading to the treatment process is high. In this paper, a new flexible fibre biofilm reactor was developed for the treatment of wastewater from fruit and vegetable processing plants. Experiments were carried out to evaluate the performance of the treatment process. Acclimatisation characteristics of the treatment process were also evaluated. The removal efficiencies for COD and BOD5 for different influent organic strengths evaluated. Results indicated that over 90% COD removal and 95% BOD5 removal could be achieved. The performance parameters were also compared with a conventional activated sludge process under similar conditions, operated in parallel. It was found that the biofilm reactor exhibited a number of advantages over the conventional reactor. These include (a) high organic loading rate, (b) long sludge retention times and low sludge discharge rate in the settling tank (about 10%), (c) elimination of the sludge recycle stream, and (d) no sludge bulking problem at high organic loading rates. Therefore, the flexible fibre biofilm reactor can provide a more efficient and cost effective treatment for wastewater from food processing industries. PMID:12755444

Yu, Q; Xu, H; Williams, P

2003-04-01

396

Impact of Tween 80 during Bacillus thuringiensis fermentation of wastewater sludges  

Microsoft Academic Search

The effect of a surface active agent, Tween 80 (0.2%, v\\/v) on production of Bacillus thuringiensis (Bt) based biopesticides using secondary wastewater sludge (non-hydrolysed (NH) and hydrolysed (TH)) as a raw material was studied in bioreactors. Hydrolysed sludge exhibited higher entomotoxicity (Tx) (49% increase) and cell\\/spore concentration vis-à-vis non-hydrolysed sludge. Amending the non-hydrolysed sludge with Tween 80 resulted in increase

S. K. Brar; M. Verma; S. Barnabé; R. D. Tyagi; J. R. Valéro; R. Surampalli

2005-01-01

397

Degradability of five aromatic compounds in a pilot wastewater treatment system  

Microsoft Academic Search

Purified terephthalic acid-manufacturing wastewater was treated aerobically with the microbial fusant Fhhh in the carrier activated sludge process at a pilot wastewater treatment plant. Biodegradability of p-toluic acid (p-Tol), benzoic acid (BA), 4-carboxybenzaldehyde (4-CBA), phthalic acid (PA) and terephthalic acid (TA) was monitored. The TOC and COD loading rate of suspended solids (SS) in the sludge were 0.53gTOCgSS?1 d?1 and

X. X. Zhang; S. P. Cheng; Y. Q. Wan; S. L. Sun; C. J. Zhu; D. Y. Zhao; W. Y. Pan

2006-01-01

398

Evaluation of perfluorinated compounds in seven wastewater treatment plants in Beijing urban areas  

Microsoft Academic Search

The presence of perfluorinated compounds (PFCs) in seven major wastewater treatment plants (WWTPs) in Beijing was investigated\\u000a in the current study. We detected nine PFCs in all the wastewater and sludge samples. Perfluorooctane acid (PFOA) is the dominant\\u000a PFCs in influents and effluents, while perfluorooctane sulfonate (PFOS) is the major contaminant in sludge. The highest PFC\\u000a concentration was found in

YuanYuan Pan; YaLi Shi; JieMing Wang; YaQi Cai

2011-01-01

399

Partitioning of nutrients and micropollutants along the sludge treatment line: a case study.  

PubMed

A 2-year sampling campaign was conducted in three wastewater treatment plants of various sizes in the Rome area to assess the occurrence of nutrients and micropollutants among primary, secondary and digested sludge. The primary purpose was to evaluate the quality of different sludge types and their suitability for agricultural use. Primary sludge was consistently more polluted than secondary in terms of organic micropollutants, whereas heavy metals partitioned equally among the sludge types. In digested sludge, the heavy metal concentrations were always below limit values proposed for agricultural utilisation. In contrast, organic micropollutants concentrated during anaerobic digestion and affected the quality of the digested sludge. Secondary sludge resulted less polluted and richer in nitrogen and phosphorus (up to three times) than primary sludge and is hence more suitable for agricultural use. Separate processing of primary and secondary sludge might therefore be an innovative option for sludge management that could maximise the possibilities of agricultural use of secondary sludge and limit disposal problems only to primary sludge. In fact, primary sludge could be easily treated and disposed of by conventional processes including thickening, anaerobic digestion, centrifugation and incineration, whereas the difficult digestibility of secondary sludge could be improved by disintegration pre-treatment before stabilisation. PMID:23589264

Gianico, A; Braguglia, C M; Mascolo, G; Mininni, G

2013-09-01

400

Industrial wastewater treatment with water re-use at a coal-fired generating station  

Microsoft Academic Search

A case-history is presented of an industrial wastewater treatment system at a 200 MW coal-fired power station. Wastewater treatment facilities were constructed in 1979 to treat low-volume wastes, coal pile runoff and ash handling wastes. A new ash handling system was constructed at the same time. The collection and combustion of various wastewater streams, and clarifier sludge handling are discussed.

1984-01-01

401

Radiation Treatment of Wastewater, (11). Treatment of Dye Wastewaters and Its Cost.  

National Technical Information Service (NTIS)

High-energy electron treatment of wastewaters from dyeing factories (in Kiryu city, Gunma Prefecture) was investigated in a series on wastewater treatment by radiation. Experiments were made on decoloration of printing and dip dyeing wastewaters using a d...

W. Kawakami S. Hashimoto T. Miyata A. Sakumoto T. Tokunaga

1978-01-01

402

Mathematical modeling of upflow anaerobic sludge blanket (UASB) reactor treating domestic wastewater.  

PubMed

Although the upflow anaerobic sludge blanket (UASB) reactor has been widely applied for domestic wastewater treatment in many developing countries, there is no sufficient mathematical model for proper design and operation of the reactor. An empirical model based on non-linear regression was developed to represent the physical and chemical removal of suspended solids (SS) in the reactor. Moreover, a simplified dynamic model based on ADM1 and the empirical model for SS removal was developed for anaerobic digestion of the entrapped SS and dissolved matter in the wastewater. The empirical model showed that effluent suspended chemical oxygen demand (COD(ss)) concentration is directly proportional to the influent COD(ss) concentration and inversely proportional to both the hydraulic retention time (HRT) of the reactor and wastewater temperature. For obtaining sufficient COD(ss) removal, the HRT of the UASB reactor must be higher than 4 h, and higher HRT than 12 h slightly improved COD(ss) removal. The dynamic model results showed that the required time for filling the reactor with sludge mainly depends on influent total chemical oxygen demand (COD(t)) concentration and HRT. The influent COD(t) concentration, HRT and temperature play a crucial role on the performance of the reactor. The results indicated that shorter HRT is needed for optimization of COD(t) removal, as compared with optimization of COD(t) conversion to methane. Based on the model results, the design HRT of the UASB reactor should be selected based on the optimization of wastewater conversion and minimization of biodegradable SS accumulation in the sludge bed, not only based on COD removal, to guarantee a stable reactor performance. PMID:23128617

Elmitwalli, Tarek

2013-01-01

403

40 CFR 61.54 - Sludge sampling.  

Code of Federal Regulations, 2010 CFR

...2) of this section, and the sludge analysis shall be performed according...of this section. (1) The sludge shall be sampled according to Method...Mercury in Wastewater Treatment Plant Sewage Sludges. A total of three...

2009-07-01

404

40 CFR 61.54 - Sludge sampling.  

Code of Federal Regulations, 2010 CFR

...2) of this section, and the sludge analysis shall be performed according...of this section. (1) The sludge shall be sampled according to Method...Mercury in Wastewater Treatment Plant Sewage Sludges. A total of three...

2010-07-01

405

Using wastewater for cooling: Increasing water reuse poses treatment challenges  

SciTech Connect

Technologies for control of biofouling, scale, corrosion and microbiologically influenced corrosion (MIC) in cooling water systems are discussed. Techniques involving water reuse and using wastewater as makeup are emphasized, and associated problems are identified. Appropriate chemical treatments, including biocides and biostats, biodispersants, sludge dispersants, corrosion inhibitors, and supplementary chemical treatments, are outlined. New and developing technologies reviewed include microorganism control based on biodispersants and on enzymes.

Lutey, R.W. [Buckman Labs. International Inc., Memphis, TN (United States)

1996-04-01

406

ISSUES WITH ALKALINE TREATMENT OF SLUDGE  

EPA Science Inventory

This presentation begins with a discussion of the use of lime and other alkaline materials from the very earliest times to the present for killing bacteria, viruses and parasites and for controlling odors in wastewaters and sludge. It answers the question "How did EPA arrive at i...

407

Polyelectrolytes: Wastewater and sewage treatment. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning polyelectrolytes in wastewater and water treatment. Topics include flocculation, coagulation, separation techniques, pollutant identification, water pollution sources, and sludge dehydration. Hospital wastewater processing, methods of synthesizing polyelectrolyte complexes, and performance evaluations of polyelectrolytes are also discussed. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1994-04-01

408

Simulation of an industrial wastewater treatment plant using artificial neural networks  

Microsoft Academic Search

This work presents a way to predict the environmental properties of the output stream from the wastewater treatment plant at Rhodiaco Ltda, one of the major chemical plants in Brazil. The industrial plant produces purified terephtalic acid and generates wastewater that should be treated in an activated sludge system. The influence of input variables is analyzed, and satisfactory predicted results

C. A. Gontarski; P. R. Rodrigues; M. Mori; L. F. Prenem

2000-01-01

409

Treatment of urban wastewater in a membrane bioreactor at high organic loading rates  

Microsoft Academic Search

Membrane bioreactors can replace the activated sludge process and the final clarification step in municipal wastewater treatment. The combination of bioreactor and crossflow microfiltration allows for a high chemical oxygen demand (COD) reduction of synthetic wastewater. From biomass, grown at high production rates in the aerobic bioreactor, energy rich biogas can be obtained in a subsequent anaerobic bioreactor. In this

Stefan Holler; Walter Trösch

2001-01-01

410

Polyelectrolytes: Wastewater and sewage treatment. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning polyelectrolytes in wastewater and water treatment. Topics include flocculation, coagulation, separation techniques, pollutant identification, water pollution sources, and sludge dehydration. Hospital wastewater processing, methods of synthesizing polyelectrolyte complexes, and performance evaluations of polyelectrolytes are also discussed. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-02-01

411

Use of sanitary sewers as wastewater pre-treatment systems  

SciTech Connect

As wastewater travels through a sewer system it undergoes changes in composition. The changes in composition may be caused by chemical, physical and/or biological processes. At present engineers do not take into consideration the impacts of these processes on the wastewater quality when designing wastewater treatment systems. However, the impact of these processes on the chemical oxygen demand, biochemical oxygen demand, nitrogen and phosphorus content of the wastewater can be significant. In the case of the biological processes, microorganisms present in the water as it travels through the sewer system are similar to those found in an activated sludge process. Given that the microorganism population and the hydraulic retention time often resembles that of an activated sludge process, it would seem only reasonable to look further into the possibility of using sewers as wastewater treatment systems. Furthermore, the plug flow regime of a sanitary sewer is inherently beneficial in terms of wastewater treatment as it is not subject to short-circuiting. The first part of this paper provides a technical review of the processes which take place in a sewer system and the resulting degradation of some of the more significant substances found in wastewater. The contribution of both the suspended biomass and the attached biomass to the degradation of substrate is also examined. The second part of this paper examines the use of the Toxchem computer model to predict the processes which are taking place in the sewer under a variety of conditions. The goal being to determine the magnitude of the degradation of substrate and dissolved oxygen depletion in a sewer system. In obtaining a better understanding of the processes that are taking place in sewer systems, engineers will be able to more accurately predict the degradation of substrates in sanitary sewer systems. This will result in a reduction in the size of wastewater treatment facilities (WWTFs).

Warith, M.A. [Ryerson Polytechnic Univ., Toronto, Ontario (Canada). Dept. of Civil Engineering] [Ryerson Polytechnic Univ., Toronto, Ontario (Canada). Dept. of Civil Engineering; Kennedy, K. [Univ. of Ottawa, Ontario (Canada). Civil Engineering Dept.] [Univ. of Ottawa, Ontario (Canada). Civil Engineering Dept.; Reitsma, R. [WCT-Delcan Corp., Victoria, British Columbia (Canada)] [WCT-Delcan Corp., Victoria, British Columbia (Canada)

1998-12-31

412

Anaerobic sequencing batch reactor treatment of coal conversion wastewaters  

SciTech Connect

The work proposed is a laboratory investigation of the AnSBR (Anaerobic Sequencing Batch Reactors) for treatment of a synthetic coal conversion wastewater. Two different strategies will be pursued. First, an AnSBR will be operated to simulate the Anaerobic Up-flow Sludge Blanket Reactor in an attempt to develop a readily settleable granular sludge. Second, operating strategies will be sought to optimize treatment, without attempting to develop settleable granular sludge. These systems will require development of more elaborate decanting mechanisms, probably including use of tube settler technology. We will use: (1) screening tests to identify compounds which are amenable to anaerobic degradation; (2) to determine those which are toxic or have an inhibitory effect; and (3) to identify the dilution required to achieve anaerobic degradation of the synthetic waste water; acclimation tests of organisms collected from different sources to the synthetic coal conversion wastewater; and Automatic Laboratory AnSBR studies. A 4-liter reactor will be operated to maintain a settleable granular anaerobic sludge when treating the synthetic coal conversion wastewater. 72 refs., 238 figs., 22 tabs.

Ketchum, L.H. Jr.; Earley, J.P.; Shen, Yutao.

1989-09-01

413

Improved performance of air-cathode single-chamber microbial fuel cell for wastewater treatment using microfiltration membranes and multiple sludge inoculation  

Microsoft Academic Search

Substantial optimization and cost reduction are required before microbial fuel cells (MFCs) can be practically applied. We show here the performance improvement of an air-cathode single-chamber MFC by using a microfiltration membrane (MFM) on the water-facing side of the cathode and using multiple aerobic sludge (AES), anaerobic sludge (ANS), and wetland sediment (WLS) as anodic inoculums. Batch test results show

Jian Sun; Yongyou Hu; Zhe Bi; Yunqing Cao

2009-01-01

414

Bioaugmentation Combined with Biofilim Process in the Treatment of Petrochemical Wastewater at Low Temperatures  

Microsoft Academic Search

Three sets of lab-scale reactors, which applied activated sludge process, bioaugmented activated sludge process and bioagumented biofilm process, respectively, were operated parallel to explore the optimum process for the treatment of petrochemical wastewater at low temperatures (13-15 degC ). Though being inoculated twice with enriched specialized bacteria, the bioaugmented activated sludge reactor (R2) did not show significant overall improvement on

Jingbo Guo; Fang Ma; Kan Jiang; Di Cui

2008-01-01

415

Wastewater Treatment: The Natural Way  

NASA Technical Reports Server (NTRS)

Wolverton Environmental Services, Inc. is widely acclaimed for innovative work in natural water purification which involves use of aquatic plants to remove pollutants from wastewater at a relatively low-cost. Haughton, Louisiana, visited Wolverton's artificial marsh test site and decided to use this method of wastewater treatment. They built an 11 acre sewage lagoon with a 70 by 900 foot artificial marsh called a vascular aquatic plant microbial filter cell. In the cell, microorganisms and rooted aquatic plants combine to absorb and digest wastewater pollutants, thereby converting sewage to relatively clean water. Raw waste water, after a period in the sewage lagoon, flows over a rock bed populated by microbes that digest nutrients and minerals from the sewage thus partially cleaning it. Additional treatment is provided by the aquatic plants growing in the rock bed, which absorb more of the pollutants and help deodorize the sewage.

1988-01-01

416

New insight into the biological treatment by activated sludge: the role of adsorption process.  

PubMed

The objective of this study was to evaluate the effect of adsorption on the biological treatment process of wastewater. In the absence of substrate in the water, activated sludge developed well in the first hour, indicating that the growth of microorganism was not directly related to substrate concentration and the dissolved organic matter in the water assays were performed, no organic matter was detected out, revealing that there was no desorption in the activated sludge adsorption process. Activated sludge batch growth experiments in the presence of different adsorption capacities indicated that specific growth rate increased as specific adsorption capacity increased. The experiment on the relationship of adsorption capacity and substrate concentration or sludge concentration was also carried out. Specific adsorption capacity increased as sludge load increased, presenting linear correlation. The experiment results showed that adsorption should be taken into account in the study of the biological treatment process of wastewater. PMID:24362248

Zhang, Xiaochun; Li, Xinrun; Zhang, Qingrui; Peng, Qiuming; Zhang, Wen; Gao, Faming

2014-02-01

417

SLUDGE DEWATERING AND DRYING  

Microsoft Academic Search

The production of wastewater treatment sludge, the basic characteristics of the sludge and the state of the water in the sludge are described in this paper. The methods for the determination of bound water content are discussed. The literature (including patents) on sludge dewatering and drying is reviewed, including vacuum filters, belt presses, centrifuges, direct dryers, indirect dryers and combined

Guohua Chen; Po Lock Yue; Arun S. Mujumdar

2002-01-01

418

Land Application of Treated Sewage Sludge in the United States: Regulatory Considerations for Risk Reduction and Determining Treatment Process Equivalency  

EPA Science Inventory

In the United States, municipal wastewater includes discharges from households, commercial businesses and various industries. Microorganisms associated with these wastes can be concentrated in the solids (sludge) which are removed during treatment operations. Beneficial reuse a...

419

Fate of silica nanoparticles in simulated primary wastewater treatment.  

PubMed

Through novel application of small-angle neutron scattering, we examined the fate of silica nanoparticles (SiO(2)NPs) during simulated primary wastewater treatment, by measuring, in real time, the colloidal behavior of SiO(2)NPs in wastewater (sewage). We examined the effects of surface functionality on SiO(2)NP fate in wastewater, by comparing both unfunctionalized (uncoated or "bare") SiO(2)NPs and SiO(2)NPs functionalized with a thin coating of a nonionic surfactant (Tween 20), which is widely used in personal care and household product formulations containing engineered oxide nanoparticles. Our results show new evidence that the surface functionality of SiO(2)NPs plays a crucial role in their flocculation and sedimentation behavior in wastewater, and thus the likely efficacy of their removal from the effluent stream during primary wastewater treatment. Uncoated SiO(2)NPs did not flocculate in wastewater over typical residence times for primary treatment. Conversely, surface-functionalized (Tween-coated) SiO(2)NPs underwent rapid flocculation in wastewater. Our results show that the surface-functionalized SiO(2)NPs are likely to be removed by sedimentation to sewage sludge (typically recycled to land), whereas uncoated SiO(2)NPs will continue through the effluent stream. While nanoparticle design is driven by use purpose, this study shows new potential for exploiting surface functionalization of nanoparticles to modify their environmental pathways. PMID:20028062

Jarvie, Helen P; Al-Obaidi, Hisham; King, Stephen M; Bowes, Michael J; Lawrence, M Jayne; Drake, Alex F; Green, Mark A; Dobson, Peter J

2009-11-15

420

Concomitant degradation of bisphenol A during ultrasonication and Fenton oxidation and production of biofertilizer from wastewater sludge  

Microsoft Academic Search

Degradation of bisphenol A (BPA), an endocrine disruptor, from wastewater sludge (WWS) has attracted great interest recently. In the present study, the effects of different pre-treatment methods, including ultrasonication (US), Fenton’s oxidation (FO) and ferro-sonication (FS) was assessed in terms of increase in solubilization of WWS and simultaneous degradation of BPA. Among US, FO and FS pre-treatment, higher suspended solids

D. P. Mohapatra; S. K. Brar; R. D. Tyagi; R. Y. Surampalli

2011-01-01

421

REDUCTION OF INTERFERING CYTOTOXICITY ASSOCIATED WITH WASTEWATER SLUDGE CONCENTRATES ASSAYED FOR INDIGENOUS ENTERIC VIRUSES  

EPA Science Inventory

Washing, freon extraction, and cationic polyelectrolyte precipitation were compared for their ability to reduce cytotoxicity associated with virus concentrates derived from beef extract eluates of wastewater sludges. Eluates concentrated by hydroextraction were usually much more ...

422

ENVIRONMENTAL REGULATIONS AND TECHNOLOGY - AUTOTHERMAL THERMOPHILIC AEROBIC DIGESTION OF MUNICIPAL WASTEWATER SLUDGE  

EPA Science Inventory

This document describes a promising technology ? autothermal thermophilic aerobic digestion ? for meeting the current and proposed U.S. federal requirements for pathogen controJ and land application of municipal wastewater sludge. Autothermal thermophilic aerobic digestion, or AT...

423

Land Application of Wastewater Sludges: A National Science Foundation Student-Originated Studies Project.  

ERIC Educational Resources Information Center

Summarizes a student-originated studies project, funded by the National Science Foundation, on land application of wastewater sludges. Describes the students' proposal, research methods, and evaluation of the project. (DS)

Bender, Timothy J.; Barnard, Walther M.

1981-01-01

424

Fate of diclofenac in municipal wastewater treatment plant - a review.  

PubMed

Diclofenac (DCF) is a common anti-inflammatory pharmaceutical that is often detected in waste wasters, effluents and surface waters. Recently, DCF was included in the watch list of substances in EU that requires its environmental monitoring in the member states. DCF is also known to harmfully affect several environmental species already at concentrations of ? 1 ?g/l. This review focuses on the occurrence and fate of DCF in conventional wastewater treatment processes. Research done in this area was gathered and analyzed in order to find out the possibilities to enhance DCF elimination during biological wastewater treatment. More precisely, human metabolism, concentrations in wastewater influents and effluents, elimination rates in the treatment train, roles of sorption and biotransformation mechanisms during the treatment as well as formation of transformation products are reported. Additionally, the effect of process configuration, i.e. conventional activated sludge (CAS), biological nutrient removal (BNR), membrane bioreactor (MBR) and attached-growth bioreactor, and process parameters, i.e. solids retention time (SRT) and hydraulic retention time (HRT) are presented. Generally, DCF is poorly biodegradable which often translates into low elimination rates during biological wastewater treatment. Only a minor portion is sorbed to sludge. MBR and attached-growth bioreactors may result in higher elimination of DCF over CAS or BNR. Long SRTs (>150 d) favor the DCF elimination due to sludge adaptation. Longer HRTs (>2-3d) could significantly increase the elimination of DCF during biological wastewater treatment. Bioaugmentation could be used to enhance DCF elimination, however, this requires more research on microbial communities that are able to degrade DCF. Also, further research is needed to gain more information about the deconjugation processes and biotic and abiotic transformation and the nature of transformation products. PMID:24791707

Vieno, Niina; Sillanpää, Mika

2014-08-01

425

Chemically reduced excess sludge production in the activated sludge process.  

PubMed

Excess sludge production from wastewater biological treatment process is highly, and the disposal of excess sludge will be forbidden in a near future, thus increased attention has been turned to look into potential technology for sludge reduction. Recently, some novel sludge reduction techniques have been developed based on chemical oxidation and metabolic uncoupling. This paper attempts to review those chemical-assisted sludge reduction processes, including sludge alkaline-thermal treatment, activated sludge-ozonation process, chlorination-combined activated sludge process, sludge reduction by metabolic uncouplers and high dissolved oxygen activated sludge process. In these combined activated sludge processes, excess sludge production can be reduced up to 100% without significant effect on process efficiency and stability. This paper would be useful when one is looking for appropriate environmentally and economically acceptable solutions for reducing or minimizing excess sludge production from wastewater biological treatment process. PMID:12656222

Liu, Yu

2003-01-01

426

Water Hyacinth Wastewater Treatment System.  

National Technical Information Service (NTIS)

A prototype water hyacinth wastewater treatment system has been in operation for two years at Walt Disney World, near Orlando, Florida. Typically, the hyacinth system removes 80-90% total suspended solids and B.O.D. from the influent stream. Major impacts...

B. R. Schwegler

1983-01-01

427

Winery Wastewater Characteristics and Treatment.  

National Technical Information Service (NTIS)

This report has been prepared to fulfill a Research, Development and Demonstration Grant. The grant was awarded to investigate a method of treatment for winery wastewaters. In brief - the grapes are harvested in the fall and are immediately pressed of the...

K. L. Sirrine P. H. Russell J. Makepeace

1977-01-01

428

VETIVER SYSTEM FOR WASTEWATER TREATMENT  

Microsoft Academic Search

Clean water is becoming one of the most scarce and valuable resources in the twenty first century as its supply is finite and its traditional source is easily polluted by industries and population growth. Existing and traditional wastewater treatment methods are expensive and in most cases are either impractical or unsuitable for smaller communities and certain industries. The Vetiver System

Paul Truong

429

Imprinted Polymers in Wastewater Treatment  

SciTech Connect

In wastewater treatment, a method that specifically recognizes a variety of impurities in a flexible manner would be useful for treatment facilities with varying needs. Current purification techniques (i.e. bacteria, oxidation, reduction, precipitation and filtration) are nonspecific and difficult to control in complex mixtures. Heavy metal removal is particularly important in improving the efficiency of wastewater treatment, as they inhibit or even destroy the bacteria used for filtration. Imprinting polymerization is a technique that allows for the efficient removal of specific compounds and has been used in purification of enantiomers. It has potential to be applied in wastewater systems with the impurities acting as the template for the imprinting polymerization. The polymer with the bound impurities intact can then be removed via precipitation. After removal of the impurity the polymer can be reused. Data for the imprinting polymerization of polyacrylates and polyacrylamides for several metal complexes will be presented. Imprinting polymerization in combination with emulsion polymerization to improve the removal of hydrophobic contaminants will be described. Removal efficiencies will be presented and compared with conventional wastewater treatment methods.

Eastman, Christopher; Goodrich, Scott; Gartner, Isabelle; Mueller, Anja

2004-03-31

430

Green Systems for Wastewater Treatment  

ERIC Educational Resources Information Center

Plants found in marshlands and wetlands in many parts of the world may play an increasing part in a very new, yet very old approach to treatment of water and wastewater--the application of biological methods. Biological water pollution control methods being utilized around the world are examined. (BT)

Environmental Science and Technology, 1975

1975-01-01

431

Application of the SCADA system in wastewater treatment plants.  

PubMed

The implementation of the SCADA system has a positive impact on the operations, maintenance, process improvement and savings for the City of Houston's Wastewater Operations branch. This paper will discuss the system's evolvement, the external/internal architecture, and the human-machine-interface graphical design. Finally, it will demonstrate the system's successes in monitoring the City's sewage and sludge collection/distribution systems, wet-weather facilities and wastewater treatment plants, complying with the USEPA requirements on the discharge, and effectively reducing the operations and maintenance costs. PMID:11515944

Dieu, B

2001-01-01

432

Preparation and characterization of titania nanoparticle produced from Ti-flocculated sludge with paper mill wastewater  

Microsoft Academic Search

Sludge disposal after flocculation with paper mill wastewater is one of the most costly and environmentally problematic challenges. In this study, an effective sludge recycling process was proposed using Ti-salt coagulant instead of the currently used Fe-salt. Paper mill wastewater flocculation using TiCl4 and FeCl3 coagulants was investigated for organic removal and precipitation efficiency. A large amount of titania nanoparticle

Suk-Hyun Na; Ho Kyong Shon; Jong Beom Kim; Hee Ju Park; Jong-Ho Kim

2011-01-01

433

Effect of ambient temperatures on disinfection efficiency of various sludge treatment technologies.  

PubMed

Sewage sludge produced during municipal wastewater treatment has to be treated efficiently in order to reduce impacts on the environment and on public health. In Germany and many countries, large quantities of sludge are reused in agriculture in order to recycle nutrients and organic material. In order to quantify the effect of different ambient temperatures on conventional and advanced sludge treatment technologies as well as on disinfection efficiency, a comprehensive research study was performed at Braunschweig Institute of Technology. The detailed results show that ambient temperature has a strong effect on biological liquid sludge stabilization and on natural dewatering and drying technologies, although microbiological quality of treated sludge, indicated by Escherichia coli concentration, does not meet the requirements for unrestricted reuse in agriculture. Composting and lime treatment of sludge are most efficient on reducing E. coli, as high temperatures and high pH values arise in the material respectively. PMID:24434963

Bauerfeld, Katrin