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


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



Minimization of excess sludge production for biological wastewater treatment  

Microsoft Academic Search

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

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



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

Code of Federal Regulations, 2013 CFR

...Slimes and sludges, automotive coating, wastewater treatment, solid waste. 721.10636...Slimes and sludges, automotive coating, wastewater treatment, solid waste. (a) Chemical...slimes and sludges, automotive coating, wastewater treatment, solid waste (PMN...



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

Code of Federal Regulations, 2013 CFR

...sludges, aluminum and iron casting, wastewater treatment, solid waste. 721.10667...sludges, aluminum and iron casting, wastewater treatment, solid waste. (a) Chemical...sludges, aluminum and iron casting, wastewater treatment, solid waste...



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. PMID:23369451



Livestock wastewater treatment using aerobic granular sludge.  


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



Polyhydroxyalkanoate (PHA) production from sludge and municipal wastewater treatment.  


Polyhydroxyalkanoates (PHAs) are biodegradable polyesters with comparable properties to some petroleum-based polyolefins. PHA production can be achieved in open, mixed microbial cultures and thereby coupled to wastewater and solid residual treatment. In this context, waste organic matter is utilised as a carbon source in activated sludge biological treatment for biopolymer synthesis. Within the EU project Routes, the feasibility of PHA production has been evaluated in processes for sludge treatment and volatile fatty acid (VFA) production and municipal wastewater treatment. This PHA production process is being investigated in four units: (i) wastewater treatment with enrichment and production of a functional biomass sustaining PHA storage capacity, (ii) acidogenic fermentation of sludge for VFA production, (iii) PHA accumulation from VFA-rich streams, and (iv) PHA recovery and characterisation. Laboratory- and pilot-scale studies demonstrated the feasibility of municipal wastewater and solid waste treatment alongside production of PHA-rich biomass. The PHA storage capacity of biomass selected under feast-famine with municipal wastewater has been increased up to 34% (g PHA g VSS(-1)) in batch accumulations with acetate during 20 h. VFAs obtained from waste activated sludge fermentation were found to be a suitable feedstock for PHA production. PMID:24434985

Morgan-Sagastume, F; Valentino, F; Hjort, M; Cirne, D; Karabegovic, L; Gerardin, F; Johansson, P; Karlsson, A; Magnusson, P; Alexandersson, T; Bengtsson, S; Majone, M; Werker, A




EPA Science Inventory

This report discusses the advantages and disadvantages of the disposal of waste alum sludge from a water treatment plant to a municipal wastewater treatment plant and is submitted in fulfillment of Grant No. 803336-01 by Novato Sanitary District and North Marin County Water Distr...


Wastewater treatment sludge as a raw material for the production of bacillus thuringiensis based biopesticides  

Microsoft Academic Search

Seven wastewater sludges of different origins and types were used as an alternate culture medium for producing Bacillus thuringiensis variety kurstaki HD-1. The sludge samples were used under three different preparations: without pre-treatment, with acid treatment (hydrolysed sludge) and the supernatant obtained after centrifugation of the hydrolysed sludge. The sludge composition varied widely with origin and the type of sludge.

Maria de Lourdes Tirado Montiel; R. D Tyagi; J. R Valero



Formation of aerobic granular sludge biofilms for sustainable wastewater treatment  

E-print Network

ENAC/ Formation of aerobic granular sludge biofilms for sustainable wastewater treatment David G to aerobic granular microbial biofilms (Confocal laser scanning microscopy analysis) Floc viscous bulking) Exopolysaccharide-producing Zoogloea spp. form the early-stage aerobic granular biofilms, and then decline


Pilot Scale Study of Excess Sludge Production Reduction in Wastewater Treatment by Ozone  

E-print Network

Pilot Scale Study of Excess Sludge Production Reduction in Wastewater Treatment by Ozone Yuan Ma-scale reactors were operated at the LaPrairie Wastewater Treatment plant (one control and one ozonated) to investigate the sludge reduction potential of partially ozonating sludge return activated sludge (RAS

Barthelat, Francois



E-print Network

CONTROL OF AN IDEAL ACTIVATED SLUDGE PROCESS IN WASTEWATER TREATMENT VIA AN ODE-PDE MODEL STEFAN DIEHL AND SEBASTIAN FAR°AS Abstract. The activated sludge process (ASP), found in most wastewater nutrients (substrate) in the incom- ing wastewater by means of activated sludge (microorganisms). The major

Diehl, Stefan


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


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



Cultivation of aerobic granular sludge for rubber wastewater treatment.  


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




EPA Science Inventory

Data for estimating average construction costs and operation and maintenance requirements are presented for thermal treatment of municipal wastewater sludges; for handling, treatment, and disposal of the strong liquor generated; and for controlling odors produced. Size ranges cov...


Radioactive and hazardous wastewater treatment and sludge stabilization by filtration  

SciTech Connect

Concentrated effluents from batch discharges of spent process solutions are mixed with filter cake from treatment of the dilute effluents and stored in a large tank at the optimum high pH for hydroxide precipitation of heavy metals. Supernate is decanted from the storage tanks and mixed with the dilute effluents before treatment. A filtration and stabilization process has been developed to treat and stored sludge as well as the concentrated wastewater slurry as it is generated. A 94% waste volume reduction over conventional technology can be achieved. Furthermore, leachate from the solidified waste filter cake meets the EPA land disposal restrictions.

Martin, H.L.; Pickett, J.B.; Langton, C.A.



Radioactive and hazardous wastewater treatment and sludge stabilization by filtration  

SciTech Connect

Concentrated effluents from batch discharges of spent process solutions are mixed with filter cake from treatment of the dilute effluents and stored in a large tank at the optimum high pH for hydroxide precipitation of heavy metals. Supernate is decanted from the storage tanks and mixed with the dilute effluents before treatment. A filtration and stabilization process has been developed to treat and stored sludge as well as the concentrated wastewater slurry as it is generated. A 94% waste volume reduction over conventional technology can be achieved. Furthermore, leachate from the solidified waste filter cake meets the EPA land disposal restrictions.

Martin, H.L.; Pickett, J.B.; Langton, C.A.



Evaluation of reed bed technology to dewater Army wastewater treatment plant sludge. Final report  

Microsoft Academic Search

As operator of over 100 small wastewater treatment plants (WWTPs), the Army has an interest in efficient and cost-effective sludge dewatering systems. Many Army wastewater treatment plants use conventional sand-drying beds to dewater sludge. However, sand drying involves costly regular removal of sludge, and sand-drying beds are vulnerable to operational problems with long drying periods during wet weather and sand

B. J. Kim; R. R. Cardenas; S. P. Chennupati



Integrated application of upflow anaerobic sludge blanket reactor for the treatment of wastewaters.  


The UASB process among other treatment methods has been recognized as a core method of an advanced technology for environmental protection. This paper highlights the treatment of seven types of wastewaters i.e. palm oil mill effluent (POME), distillery wastewater, slaughterhouse wastewater, piggery wastewater, dairy wastewater, fishery wastewater and municipal wastewater (black and gray) by UASB process. The purpose of this study is to explore the pollution load of these wastewaters and their treatment potential use in upflow anaerobic sludge blanket process. The general characterization of wastewater, treatment in UASB reactor with operational parameters and reactor performance in terms of COD removal and biogas production are thoroughly discussed in the paper. The concrete data illustrates the reactor configuration, thus giving maximum awareness about upflow anaerobic sludge blanket reactor for further research. The future aspects for research needs are also outlined. PMID:21764417

Latif, Muhammad Asif; Ghufran, Rumana; Wahid, Zularisam Abdul; Ahmad, Anwar



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



[Pollution characteristics of heavy metals in sludge from wastewater treatment plants and sludge disposal in Chinese coastal areas].  


Thirteen sludge samples from Guangzhou, Shanghai and Dalian were collected and analysed for heavy metals to investigate the distribution and variation trend of heavy metals in sludge from wastewater treatment plants in Chinese coastal areas. The results showed that contents of heavy metals in sludge varied significantly, and the average contents exhibited an order of Cr > Zn > Cu > Pb > As > Hg > Cd. Additionally, contents of Cr, Cu and As exceeded their corresponding standard levels. Compared with contents of heavy metals in 2006 and 2001, content of Zn in sludge increased while contents of Cr, Cu and As decreased. Results also indicated that the industrial sludge was more seriously polluted than domestic sludge in terms of Zn, Cu and As. Only 23% sludge samples exceeded the standards for fertilization of sludge, suggesting that most of the sludge could be disposed by land application. These results also provide further information about the establishment of ocean disposal assessment for sludge. PMID:23798112

Zhang, Can; Chen, Hong; Yu, Yi-Xuan; Wang, Li-Jun; Han, Jian-Bo; Tao, Ping



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



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


Antimicrobial resistance in Escherichia coli isolated in inflow, effluent and sludge from municipal wastewater treatment plants  

Microsoft Academic Search

Antimicrobial resistance is a phenomenon of increasing importance. Sewage treatment processes are a vehicle for dissemination of resistant bacteria in both aquatic and terrestrial environments. To assess the number of antimicrobial resistant E. coli present in the wastewater inflow, effluent and sludge from urban sewage treatment plants in Portugal, 42 samples of crude inflow, treated effluent and sludge were collected

P. Martins Da Costa; P. Vaz-Pires; F. Bernardo



The Reactive Light Yellow Dye Wastewater Treatment by Sewage Sludge-Based Activated Carbon  

Microsoft Academic Search

The paper is aim to discuss the dye wastewater treatment by sewage sludge-based adsorbent. The adsorbent derived from sewage sludge , which produced through phosphoric acid-microwave method, and commercia activated carbon (ACC) were tested in the process of the Reactive Light Yellow dye wastewater treatment. The effects of pH value, contact time and the adsorbents' amount on the adsorption efficiency

Yang Lijun; Dai Qunwei



A nonlinear observer design for an activated sludge wastewater treatment process  

E-print Network

, route de Luxembourg, L - 4009 Esch-Alzette, Luxembourg Abstract This paper treats the problem;Activated sludge wastewater treatment is a highly complex physical, chemical and bio- logical process for modeling the benchmark with a single Reactor Activated Sludge Process. This reduced model contains five

Paris-Sud XI, Université de


Microbial Products of Activated Sludge in Biological Wastewater Treatment Systems: A Critical Review  

Microsoft Academic Search

Activated sludge is subjected to transient conditions, resulting in the enhanced production of microbial products (i.e., extracellular polymeric substances, soluble microbial products, and internal storage products). The authors review the status of the microbial products formed by activated sludge in wastewater treatment systems. They outline the fundamental facets of their formation and metabolism, define their key characteristics and important roles,




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


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



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


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.


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


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



Wastewater treatment sludge as a raw material for the production of Bacillus thuringiensis based biopesticides.  


Seven wastewater sludges of different origins and types were used as an alternate culture medium for producing Bacillus thuringiensis variety kurstaki HD-1. The sludge samples were used under three different preparations: without pre-treatment, with acid treatment (hydrolysed sludge) and the supernatant obtained after centrifugation of the hydrolysed sludge. The sludge composition varied widely with origin and the type of sludge. Growth and sporulation were evaluated by the total viable cell count and spore count of the preparations. Growth, sporulation and endotoxin production were affected by the sludge origin. Hydrolysed sludge gave the highest viable cell and spore counts while the liquid phase (supernatant) gave the lowest. Non-hydrolysed primary sludge from Valcartier was unable to sustain bacterial growth because of its low pH. Bioassays were conducted against larvae of spruce budworm to evaluate entomotoxic potential of the preparations obtained. In general, sludge hydrolysis increased the entomotoxicity yields. Similar entomotoxicity was observed in Black Lake secondary sludge (4100 IU/microL) as that obtained in the reference soya medium (3800 IU/microL). The use of the sludge supernatant (liquid phase) was not recommended due to the low entomotoxic potential obtained. PMID:12230163

Montiel, M D; Tyagi, R D; Valero, J R



Influence of pharmaceutical residues on the structure of activated sludge bacterial communities in wastewater treatment bioreactors  

Microsoft Academic Search

Concern is growing over contamination of the environment with pharmaceuticals because of their widespread use and incomplete removal during wastewater treatment, where microorganisms drive the key processes. The influence of pharmaceuticals on bacterial community structure in activated sludge was assessed in small-scale wastewater treatment bioreactors containing different concentrations (5, 50, 200 and 500?gL?1) of several commonly used pharmaceuticals (ibuprofen, naproxen,

Barbara Kraigher; Tina Kosjek; Ester Heath; Boris Kompare; Ines Mandic-Mulec



Toxicity formation and distribution in activated sludge during treatment of N,N-dimethylformamide (DMF) wastewater.  


The organic toxicity of sludge in land applications is a critical issue; however, minimal attention has been given to the mechanism of toxicity formation during high-strength wastewater treatment. To investigate the relevant factors that contribute to sludge toxicity, synthetic wastewater with N,N-dimethylformamide (DMF) was treated in a sequential aerobic activated sludge reactor. The acute toxicity of sludge, which is characterised by the inhibition rate of luminous bacteria T3, is the focus of this study. Using an operational time of 28 days and a hydraulic retention time of 12h, the study demonstrated a positive relationship between the acute toxicity of sludge and the influent DMF concentration; the toxicity centralised in the intracellular and inner sections of extracellular polymeric substances (EPS) in sludge flocs. Due to increased concentrations of DMF, which ranged from 40 to 200mgL(-1), the sludge toxicity increased from 25 to 45%. The organic toxicity in sludge flocs was primarily contributed by the biodegradation of DMF rather than adsorption of DMF. Additional investigation revealed a significant correlation between the properties of the bacterial community and sludge toxicity. PMID:24316801

Yang, Na; Chen, Xiurong; Lin, Fengkai; Ding, Yi; Zhao, Jianguo; Chen, Shanjia



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


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



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


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



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


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



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


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



Temperature effect on shear flow and thixotropic behavior of residual sludge from wastewater treatment plant  

NASA Astrophysics Data System (ADS)

The temperature and shear rate effects on rheological behavior of residual sludge from wastewater treatment plant was investigated in this work. The model of Herschel-Bulkley was used to fit the shear rate dependence of the shear stress. The temperature increase induced not only an increase in the yield stress and the flow index of sludge but also a decrease of the consistency index of sludge. The temperature dependence of limit viscosity at high shear rate of the residual sludge was fitted by an Arrhenius equation. For constant shear rate applied on the sludge at 20 °C a thixotropic behavior was observed and analyzed using a modified model of Herschel-Bulkley in which a structural parameter ? was included in order to account for the time-dependent effect.

Hammadi, L.; Ponton, A.; Belhadri, M.



Wastewater sludge management options for Honduras  

E-print Network

Sludge management is a fundamental area of concern across wastewater treatment systems in Honduras. The lack of timely sludge removal has led to declining plant performance in many facilities throughout the country. In ...

Bhattacharya, Mahua, M. Eng. Massachusetts Institute of Technology.



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


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



Mechanisms involved in Escherichia coli and Serratia marcescens removal during activated sludge wastewater treatment.  


Wastewater treatment reduces environmental contamination by removing gross solids and mitigating the effects of pollution. Treatment also reduces the number of indicator organisms and pathogens. In this work, the fates of two coliform bacteria, Escherichia coli and Serratia marcescens, were analyzed in an activated sludge process to determine the main mechanisms involved in the reduction of pathogenic microorganisms during wastewater treatment. These bacteria, modified to express green fluorescent protein, were inoculated in an activated sludge unit and in batch systems containing wastewater. The results suggested that, among the different biological factors implied in bacterial removal, bacterivorous protozoa play a key role. Moreover, a representative number of bacteria persisted in the system as free-living or embedded cells, but their distribution into liquid or solid fractions varied depending on the bacterium tested, questioning the real value of bacterial indicators for the control of wastewater treatment process. Additionally, viable but nonculturable cells constituted an important part of the bacterial population adhered to solid fractions, what can be derived from the competition relationships with native bacteria, present in high densities in this environment. These facts, taken together, emphasize the need for reliable quantitative and qualitative analysis tools for the evaluation of pathogenic microbial composition in sludge, which could represent an undefined risk to public health and ecosystem functions when considering its recycling. PMID:25044599

Orruño, Maite; Garaizabal, Idoia; Bravo, Zaloa; Parada, Claudia; Barcina, Isabel; Arana, Inés



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


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



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


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 by determining the fate of solids and selected nutrients. Parameters assessed in both the reed bed influent and effluent: total suspended solids, biochemical oxygen demand, nitrate-nitrogen and total phosphorus. In addition, the following metals were studied in the reed bed influent, effluent and Phragmites plant tissue and the sludge core biomass: boron, cadmium, chromium, copper, iron, lead, manganese, molybdenum, nickel, and zinc. The removal efficiencies for sludge dewatering, total suspended solids and biochemical oxygen demand were all over 90%. Nitrate and total phosphorus removal rates were 90% and 80% respectively. Overall metals removal efficient was 87%. Copper was the only metal in the sludge biomass that exceeded the standards set by the Massachusetts Department of Environmental Protection for land disposal of sludge. The highest metal concentrations, for the most part, tended to be in the lower tier of the sludge profile. The exception was boron, which was more concentrated in the middle tier of the sludge profile. The data and results presented in this paper support the notion that reed bed sludge treatment systems and the use of reed beds provide an efficient and cost effective alternative for municipal sludge treatment. PMID:11804125

Begg, J S; Lavigne, R L; Veneman, P L



Coagulant recovery from water treatment plant sludge and reuse in post-treatment of UASB reactor effluent treating municipal wastewater.  


In the present study, feasibility of recovering the coagulant from water treatment plant sludge with sulphuric acid and reusing it in post-treatment of upflow anaerobic sludge blanket (UASB) reactor effluent treating municipal wastewater were studied. The optimum conditions for coagulant recovery from water treatment plant sludge were investigated using response surface methodology (RSM). Sludge obtained from plants that use polyaluminium chloride (PACl) and alum coagulant was utilised for the study. Effect of three variables, pH, solid content and mixing time was studied using a Box-Behnken statistical experimental design. RSM model was developed based on the experimental aluminium recovery, and the response plots were developed. Results of the study showed significant effects of all the three variables and their interactions in the recovery process. The optimum aluminium recovery of 73.26 and 62.73 % from PACl sludge and alum sludge, respectively, was obtained at pH of 2.0, solid content of 0.5 % and mixing time of 30 min. The recovered coagulant solution had elevated concentrations of certain metals and chemical oxygen demand (COD) which raised concern about its reuse potential in water treatment. Hence, the coagulant recovered from PACl sludge was reused as coagulant for post-treatment of UASB reactor effluent treating municipal wastewater. The recovered coagulant gave 71 % COD, 80 % turbidity, 89 % phosphate, 77 % suspended solids and 99.5 % total coliform removal at 25 mg Al/L. Fresh PACl also gave similar performance but at higher dose of 40 mg Al/L. The results suggest that coagulant can be recovered from water treatment plant sludge and can be used to treat UASB reactor effluent treating municipal wastewater which can reduce the consumption of fresh coagulant in wastewater treatment. PMID:24777321

Nair, Abhilash T; Ahammed, M Mansoor



Non-filamentous sludge bulking caused by a deficiency of nitrogen in industrial wastewater treatment.  


Deficiency in the nutrient supply such as nitrogen usually results in activated sludge bulking and this phenomenon often takes place in the industrial wastewater treatment plants with activated sludge process. The effects of nitrogen deficiency on activated sludge bulking were studied specially in some experiments carried out in a sequencing batch reactor fed with brewing process wastewater in this paper. The experimental results showed that the sludge settled properly at an influent BOD/N value of 100/4. When the value of BOD/N was 100/3, filaments had an excessive growth at one time during the reaction process. Afterwards, the number of filamentous bacteria began to reduce and simultaneously an excessive growth of viscous Zoogloea with high percentage of moisture was observed and non-filamentous activated sludge bulking occurred. When the influent BOD/N value was 100/2, the excessive growth of filamentous microorganisms could not be observed at all times and the sludge characterization was similar to the case in which BOD/N value was 100/3. When the value of influent BOD/N was 100/0.94, more serious non-filamentous bulking occurred. Furthermore, the effects of nitrogen deficiency on the nitrogen sources and phosphorus sources utilization rate and the COD removal rate were investigated in the experiments. PMID:12906302

Peng, Y; Gao, C; Wang, S; Ozaki, M; Takigawa, A



Calorific value of wastewater plant sludges  

SciTech Connect

Calorific values of wastewater plant sludges are best determined using an oxygen bomb calorimeter, an apparatus which is not readily available in many plants. Using a variety of sludges from thirteen municipal wastewater treatment plants in southeastern Wisconsin, an excellent correlation is established between the calorific value and chemical oxygen demand of the sludges. A well-tested recommended procedure for conducting the chemical oxygen demand of wet sludges and semi-dry cakes is also presented. (Refs. 4).

Zanoni, A.E.; Mueller, D.L.



Effects of chromium on activated sludge and on the performance of wastewater treatment plants: A review.  


Chromium is a heavy metal of commercial importance, thus significant amounts are released in wastewaters. Chromium in wastewaters and in the aquatic environment is primarily encountered in oxidation stages +3 (Cr((III))) and +6 (Cr((VI))). Recent publications suggest that Cr((VI)) compounds are more toxic than Cr((III)) ones, while Cr((III)) has been identified as trace element, at least for complex organisms. With respect to chromium species mobility, Cr((VI)) can cross cellular membranes, which then may be oxidized to Cr((III)) and react with intracellular biomolecules. Clear conclusions cannot be derived about the critical chromium concentrations that affect activated sludge growth, as the latter is a function of a number of factors. Broadly, may be supported that activated sludge growth is stimulated at Cr((III)) concentrations up to 15 mg L(-1), above which is inhibited, with lethal doses lying above 160 mg Cr((III)) L(-1). On the other hand, literature data on Cr((VI)) effects on activated sludge are even more controversial. A number of reports support that Cr((VI)) is toxic to activated sludge at concentrations above 5 mg L(-1), while others report growth stimulation at concentrations up to 25 mg L(-1). However, all reports agree that Cr((VI)) is definitely an activated sludge growth inhibitor at higher concentrations, while 80 mg Cr((VI)) L(-1) have been identified as lethal dose. A number of factors have been identified to influence chromium toxicity on activated sludge, such as, pH, biomass concentration, presence of organic substances or other heavy metals, acclimation process, exposure time, etc. Naturally, the presence of chromium species in wastewaters may affect the performance of wastewater treatment plants often causing malfunctions, particularly for industrial wastewaters containing relatively high chromium concentrations. The present work reviews in a critical way the published literature on chromium effects on activated sludge, and on the operation of wastewater treatment plants. PMID:22154108

Vaiopoulou, Eleni; Gikas, Petros



Aerobic treatment of winery wastewater using a jet-loop activated sludge reactor  

Microsoft Academic Search

A jet-loop activated sludge reactor (JLR) of 15 dm3 working volume was used for the aerobic treatment of winery wastewater (WW). The reactor was operated continuously for more than 12 months using WW from different wineries and collected in different periods of the year with CODs that ranged between 0.8 and 12.8 kg m?3. Loading rates were from 0.4 to

Maurizio Petruccioli; J. Cardoso Duarte; Ana Eusebio; Federico Federici



Assessment of characteristic distribution of PCDD/Fs and BFRs in sludge generated at municipal and industrial wastewater treatment plants.  


The presence of polychlorinated dibenzo-p-dioxins and furan (PCDD/Fs) and brominated flame retardants (BFRs) in sludge generated at municipal wastewater treatment plants (MWTPs) and industrial wastewater treatment plants (IWTPs) was investigated. The concentrations of these pollutants were in the following ranges: 5.38-7947ngkg(-1)dw (0.02-49.9ngWHO-TEQkg(-1) dw) for 17 PCDD/Fs, 17.5-66761?gkg(-1)dw for 27 polybrominated diphenyl ethers (PBDEs), 1.55-29604?gkg(-1)dw for hexabromocyclododecanes (HBCDs) (?-, ?-, and ?-diastereomers), and 4.01-618?gkg(-1)dw for tetrabromobisphenol A (TBBPA). Generally, the levels of each compound in the sewage-sludge samples were higher than those in the industrial-sludge samples with some exceptions. The characteristic distribution profiles of target compounds were observed for different types of sludge and different sources of wastewater. High-chlorinated PCDD/Fs were dominant in all samples except those from the textile industry. The distribution of the BFRs in industrial-sludge samples varied, whereas that of the BFRs in sewage-sludge samples was consistent. The proportion of penta-BDEs in sewage sludge was higher than that in industrial sludge, even though BDE-209 was the most dominant congener in all the samples. For HBCDs, the distribution of diastereomers (?-, ?-, and ?-HBCD) was similar across sludge samples that had the same source of wastewater and treatment processes. PMID:22595527

Hwang, In-Kyu; Kang, Hee-Hyung; Lee, In-Seok; Oh, Jeong-Eun



Production of biodiesel and other valuable chemicals from wastewater treatment plant sludges  

US Patent & Trademark Office Database

A process for producing biodiesel has been invented by first extracting lipids from the sludges generated during primary and/or biological treatment of municipal, agricultural, and industrial wastewaters using primary, secondary, and tertiary treatments followed by the transesterification of the extracted lipids using transesterification conversion into alcohol-based esters. The resulting products from this process include biodiesel, glycerol, lipid-free proteins, various other useful chemicals and an aqueous-based substrate well suited for optimized digestion within subsequent biological digestion (either aerobic or anaerobic). The lipids extracted from the sludges containing high levels of microorganisms are phospholipids which can also be directly used as lecithin. The extraction of the lipids from the sludges will be performed using chemical extraction techniques with the transesterification of the extracted lipids accomplished using basic, acidic, and/or a combination of the two transesterification techniques.



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. PMID:18392150

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



Treatment of swine wastewater using chemically modified zeolite and bioflocculant from activated sludge.  


Sterilization, alkaline-thermal and acid-thermal treatments were applied to activated sludge and the pre-treated sludge was used as raw material for Rhodococcus R3 to produce polymeric substances. After 60 h of fermentation, bioflocculant of 2.7 and 4.2 g L(-1) were produced in sterilized and alkaline-thermal treated sludge as compared to that of 0.9 g L(-1) in acid-thermal treated sludge. Response surface methodology (RSM) was employed to optimize the treatment process of swine wastewater using the composite of bioflocculant and zeolite modified by calcining with MgO. The optimal flocculating conditions were bioflocculant of 24 mg L(-1), modified zeolite of 12 g L(-1), CaCl2 of 16 mg L(-1), pH of 8.3 and contact time of 55 min, and the corresponding removal rates of COD, ammonium and turbidity were 87.9%, 86.9%, and 94.8%. The use of the composite by RSM provides a feasible way to improve the pollutant removal efficiencies and recycle high-level of ammonium from wastewater. PMID:23810950

Guo, Junyuan; Yang, Chunping; Zeng, Guangming



Sludge valorization from wastewater treatment plant to its application on the ceramic industry.  


The main aim of this study is to assess the effect of incorporating waste sludge on the properties and microstructure of clay used for bricks manufacturing. Wastewater treatment plants produce annually a great volume of sludge. Replacing clay in a ceramic body with different proportions of sludge can reduce the cost due to the utilization of waste and, at the same time, it can help to solve an environmental problem. Compositions were prepared with additions of 1%, 2.5%, 5%, 7.5%, 10% and 15% wt% waste sludge in body clay. In order to determine the technological properties, such as bulk density, linear shrinkage, water suction, water absorption and compressive strength, press-moulded bodies were fired at 950 °C for coherently bonding particles in order to enhance the strength and the other engineering properties of the compacted particles. Thermal heating destroys organic remainder and stabilizes inorganic materials and metals by incorporating oxides from the elemental constituent into a ceramic-like material. Results have shown that incorporating up to 5 wt% of sludge is beneficial for clay bricks. By contrast, the incorporation of sludge amounts over 5 wt% causes deterioration on the mechanical properties, therefore producing low-quality bricks. PMID:21723033

Martínez-García, C; Eliche-Quesada, D; Pérez-Villarejo, L; Iglesias-Godino, F J; Corpas-Iglesias, F A



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


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



A Cost-Effectiveness Analysis of Seminatural Wetlands and Activated Sludge Wastewater-Treatment Systems  

NASA Astrophysics Data System (ADS)

A cost-effectiveness analysis was performed to evaluate the competitiveness of seminatural Free Water Surface (FWS) wetlands compared to traditional wastewater-treatment plants. Six scenarios of the service costs of three FWS wetlands and three different wastewater-treatment plants based on active sludge processes were compared. The six scenarios were all equally effective in their wastewater-treatment capacity. The service costs were estimated using real accounting data from an experimental wetland and by means of a market survey. Some assumptions had to be made to perform the analysis. A reference wastewater situation was established to solve the problem of the different levels of dilution that characterize the inflow water of the different systems; the land purchase cost was excluded from the analysis, considering the use of public land as shared social services, and an equal life span for both seminatural and traditional wastewater-treatment plants was set. The results suggest that seminatural systems are competitive with traditional biotechnological systems, with an average service cost improvement of 2.1-fold to 8-fold, according to the specific solution and discount rate. The main improvement factor was the lower maintenance cost of the seminatural systems, due to the self-regulating, low artificial energy inputs and the absence of waste to be disposed. In this work, only the waste-treatment capacity of wetlands was considered as a parameter for the economic competitiveness analysis. Other goods/services and environmental benefits provided by FWS wetlands were not considered.

Mannino, Ilda; Franco, Daniel; Piccioni, Enrico; Favero, Laura; Mattiuzzo, Erika; Zanetto, Gabriele



A cost-effectiveness analysis of seminatural wetlands and activated sludge wastewater-treatment systems.  


A cost-effectiveness analysis was performed to evaluate the competitiveness of seminatural Free Water Surface (FWS) wetlands compared to traditional wastewater-treatment plants. Six scenarios of the service costs of three FWS wetlands and three different wastewater-treatment plants based on active sludge processes were compared. The six scenarios were all equally effective in their wastewater-treatment capacity. The service costs were estimated using real accounting data from an experimental wetland and by means of a market survey. Some assumptions had to be made to perform the analysis. A reference wastewater situation was established to solve the problem of the different levels of dilution that characterize the inflow water of the different systems; the land purchase cost was excluded from the analysis, considering the use of public land as shared social services, and an equal life span for both seminatural and traditional wastewater-treatment plants was set. The results suggest that seminatural systems are competitive with traditional biotechnological systems, with an average service cost improvement of 2.1-fold to 8-fold, according to the specific solution and discount rate. The main improvement factor was the lower maintenance cost of the seminatural systems, due to the self-regulating, low artificial energy inputs and the absence of waste to be disposed. In this work, only the waste-treatment capacity of wetlands was considered as a parameter for the economic competitiveness analysis. Other goods/services and environmental benefits provided by FWS wetlands were not considered. PMID:17943345

Mannino, Ilda; Franco, Daniel; Piccioni, Enrico; Favero, Laura; Mattiuzzo, Erika; Zanetto, Gabriele



Heavy metal extraction from PCB wastewater treatment sludge by sulfuric acid.  


Heavy metals contaminated wastewater sludge is classified as hazardous solid waste and needs to be properly treated to prevent releasing heavy metals to the environment. In this study, the wastewater treatment sludge from a printed circuit board manufacturing plant was treated in a batch reactor by sulfuric acid to remove the contained heavy metals. The effects of sulfuric acid concentration and solid to liquid ratio on the heavy metal removal efficiencies were investigated. The experimental results showed that the total and individual heavy metal removal efficiencies increased with increasing sulfuric acid concentration, but decreased with increasing solid to liquid ratio. A mathematical model was developed to predict the residual sludge weights at varying sulfuric concentrations and solid to liquid ratios. The trivalent heavy metal ions, iron and chromium were more difficult to be removed than the divalent ions, copper, zinc, nickel, and cadmium. For 5 g/L solid to liquid ratio, more than 99.9% of heavy metals can be removed from the sludge by treating with 0.5M sulfuric acid in 2h. PMID:20079970

Kuan, Yu-Chung; Lee, I-Hsien; Chern, Jia-Ming



Reduction of sludge generation by the addition of support material in a cyclic activated sludge system for municipal wastewater treatment.  


An innovative biomass carrier (Biobob®) was tested for municipal wastewater treatment in an activated sludge system to evaluate the pollutant removal performance and the sludge generation for different carrier volumes. The experiment was carried out in a pilot-scale cyclic activated sludge system (CASS®) built with three cylindrical tanks in a series: an anoxic selector (2.1 m(3)), an aerobic selector (2.5 m(3)) and the main aerobic reactor (25.1 m(3)). The results showed that by adding the Biobob® carrier decreased the MLVSS concentration, which consequently reduced the waste sludge production of the system. Having 7% and 18% (v/v) support material in the aerobic reactor, the observed biomass yield decreased 18% and 36%, respectively, relative to the reactor operated with suspended biomass. The addition of media did not affect the system's performance for COD and TSS removal. However, TKN and TN removal were improved by 24% and 14%, respectively, using 18% (v/v) carrier. PMID:23831747

Araujo, Moacir Messias de; Lermontov, André; Araujo, Philippe Lopes da Silva; Zaiat, Marcelo



Assessment of fates of estrogens in wastewater and sludge from various types of wastewater treatment plants  

Microsoft Academic Search

We measured five estrogens in the wastewater samples from the municipal wastewater treatment plants (M-WWTPs), livestock wastewater treatment plants (L-WWTPs), hospital WWTPs (H-WWTPs) and pharmaceutical manufacture WWTPs (P-WWTPs) in Korea. The L-WWTPs showed the highest total concentration (0.195–10.4?gL?1) of estrogens in the influents, followed by the M-WWTPs (0.028–1.15?gL?1), H-WWTPs (0.068–0.130?gL?1) and P-WWTPs (0.015–0.070?gL?1). Like the influents, the L-WWTPs (0.003–0.729?gL?1) and

Won-Jin Sim; Ji-Woo Lee; Sun-Kyoung Shin; Ki-Bong Song; Jeong-Eun Oh




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...


Preparation and characteristics of bacterial polymer using pre-treated sludge from swine wastewater treatment plant.  


Sterilization, alkaline-thermal, and acid-thermal treatments were applied to different suspended sludge solids (SSS) concentrations and the pre-treated sludge was used as raw material for bioflocculant-producing bacteria R3 to produce bioflocculant. After 60 h of fermentation, three forms of bioflocculant (broth, capsular, and slime) were extracted, and maximum broth bioflocculant of 2.9 and 4.1 g L(-1) were produced in sterilized and alkaline-thermal treated sludge as compared to that of 1.8 g L(-1) in acid-thermal treated sludge. Higher bioflocculant quantity was produced in SS of 15, 25, and 35 g L(-1) compared to that produced in SS of 45, 55, and 65 g L(-1). Bioflocculant combined with 0.5 g Ca(2+) in 1.0 L kaolin suspension acted as conditioning agent, and maximum flocculating activity of 94.5% and 92.8% was achieved using broth and slime bioflocculant, respectively. The results demonstrated that wastewater sludge could be used as sources to prepare bioflocculants. PMID:24333626

Guo, Junyuan; Yang, Chunping; Peng, Lanyan



Anaerobic treatment of low-strength brewery wastewater in expanded granular sludge bed reactor.  


Anaerobic treatment of low-strength brewery wastewater, with influent total chemical oxygen demand (COD) (CODin) concentrations ranging from 550 to 825 mg/L, was investigated in a pilot-scale 225.5-L expanded granular sludge bed (EGSB) reactor. In an experiment in which the temperature was lowered stepwise from 30 to 12 degrees C, the COD removal efficiency decreased from 73 to 35%, at organic loading rates (OLR) of 11-16.5 g COD/L/d. The applied hydraulic retention time (HRT) and liquid upflow velocity (Vup) were 1.2 h and 5.8 m/h, respectively. Under these conditions, the acidified fraction of the CODin varied from 45 to 90%. In addition to the expected drop in reactor performance, problems with sludge retention were also observed. In a subsequent experiment set at 20 degrees C, COD removal efficiencies exceeding 80% were obtained at an OLR up to 12.6 g COD/L/d, with CODin between 630 and 715 mg/L. The values of HRT and Vup applied were 2.1-1.2 h, and 4.4-7.2 m/h, respectively. The acidified fraction of the CODin was above 90%, but sludge washout was not significant. These results indicate that the EGSB potentials can be further explored for the anaerobic treatment of low-strength brewery wastewater, even at lower temperatures. PMID:10327587

Kato, M T; Rebac, S; Lettinga, G



Effect of microalgae/activated sludge ratio on cooperative treatment of anaerobic effluent of municipal wastewater.  


In this work, capability of the green microalga (MA), Chlorella vulgaris, in treating synthetic anaerobic effluent of municipal wastewater was investigated. While pure C. vulgaris (100 % MA) provided maximum soluble chemical oxygen demand (sCOD) and N-NH4(+) removal efficiencies of 27 and 72 % respectively, addition of activated sludge (AS) to MA in different mass ratios (91, 80, 66.7, 9 % MA) improved wastewater treatment efficiency. Thus giving maximum sCOD and N-NH4(+) removal efficiencies 85 and 86.3 % (for MA/AS = 10/1), respectively. Utilizing AS without C. vulgaris, for treating the synthetic wastewater resulted in 87 % maximum sCOD and 42 % maximum N-NH4(+) removal efficiencies. Furthermore, algal growth and specific growth rates were measured in the systems with microalga as the dominant cellular population. As a result, faster algal growth was observed in mixed systems. Specific growth rate of C. vulgaris was 0.14 (day(-1)) in 100 % MA and 0.39 (day(-1)) in 80 % MA. Finally, data gathered by online measurement of dissolved oxygen indicate that algae-activated sludge mixture improves photosynthetic activity of examined microalga strain during anaerobic effluent treatment. PMID:24052335

Roudsari, Fatemeh Pourasgharian; Mehrnia, Mohammad Reza; Asadi, Akram; Moayedi, Zohreh; Ranjbar, Reza



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


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



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.



Changes in wastewater treatment performance and activated sludge properties of a membrane bioreactor at low temperature operation.  


The membrane bioreactor (MBR) activated sludge process is being applied more and more for wastewater treatment due to its high treatment efficiency and low space requirement. However, the usefulness of the MBR process in low-temperature zones is less studied than that under normal conditions. This study determined the effect of low temperature (?13 °C) operation on MBR performance and activated sludge characteristics. When the wastewater temperature decreased from 22 °C to 13 °C, the average effluent COD concentration increased from (10 ± 5) to (25 ± 4) mg L(-1) and the nitrogen removal efficiency appeared not to be affected. The abundance and diversity of nitrifying bacteria such as Nitrosospira (ammonia-oxidizing bacteria) and Nitrospira (nitrite-oxidizing bacteria) in the activated sludge were reduced under low temperature exposure. The total biomass concentration decreased from about 10?000 mg COD L(-1) at room temperature to 8200 mg COD L(-1) at 13 °C at the same solid retention time. Furthermore, the sludge became bulking at 13 °C with a significant increase in the sludge volume index. The resultant sludge bulking was accompanied by accelerated membrane fouling resulting in a two-fold increase in the frequency of membrane cleaning. The results suggest that the performance of the MBR activated sludge process deteriorated at low wastewater temperatures even though the effluent water quality was still good enough for its applications in low temperature zones. PMID:25003580

Zhang, Chiqian; Wang, Guangzhi; Hu, Zhiqiang



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

Microsoft Academic Search

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°C. More than 90% TOC removal was

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



Heavy metal concentration and speciation of seven representative municipal sludges from wastewater treatment plants in Northeast China  

Microsoft Academic Search

The analysis of heavy metals is very important for assessing the feasibility of the agricultural utilization for the municipal\\u000a sludge. In this paper, a four-step sequential extraction method was applied to extract heavy metals (Cu, Zn, Mn, Cr, and Ni)\\u000a in municipal sludges from seven individual wastewater treatment plants located in Jilin and Heilongjiang Province, China,\\u000a for estimating the mobility

Jiangcheng Tu; Qingliang Zhao; Liangliang Wei; Qianqian Yang


Short-Term Effects of Low pH on the Microfauna of an Activated Sludge Wastewater Treatment System  

Microsoft Academic Search

Optimum pH for biological (e.g., activated sludge) wastewater treatment is stat- ed to lie between pH 6.5 and 8.0; however, the pH of processed effluent from thermomechanical pulp mills is closer to 4.5 and 5.5. Consequently, pH adjust- ment of effluent is required with associated costs. The ability of the microfaunal community (protozoa and metazoa) of activated sludge to survive




Toxicity of ammonia nitrogen to ciliated protozoa Stentor coeruleus and Coleps hirtus isolated from activated sludge of wastewater treatment plants.  


We assessed the toxicity of ammonia ions to Stentor coeruleus and Coleps hirtus (Protozoa) isolated from activated sludge taken from two municipal wastewater treatment plants in southern Poland. Stentor coeruleus is a rarely occurring species in activated sludge, unlike the widespread Coleps hirtus. The mean LC50 values (concentration causing 50 % mortality) calculated for the 24 h tests differed hugely between the tested species: 43.03 mg NH(4+) dm(-3) for Stentor coeruleus and 441.12 mg NH(4+) dm(-3) for Coleps hirtus. The ammonia ion concentration apparently is an important factor in the occurrence of these protozoan species in activated sludge. PMID:22976439

Klimek, Beata; Fyda, Janusz; Pajdak-Stós, Agnieszka; Kocerba, Wioleta; Fia?kowska, Edyta; Sobczyk, Mateusz



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


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



Fate and behaviour of copper and zinc in secondary biological wastewater treatment processes: II Removal at varying sludge age  

Microsoft Academic Search

The mechanisms for the removal of heavy metals during secondary biological treatment of wastewater, with particular emphasis on the activated sludge process, are considered. It is concluded that the predominant mechanism is the entrapment and co?settlement of insoluble metal species in the mixed liquor (biomass). Secondary extracellular polymeric materials, particularly extracellular polysaccharides and other capsule?forming materials, may also play a

A. Santos; P. Barton; E. Cartmell; F. Coulon; R. S. Crane; P. Hillis; J. N. Lester; T. Stephenson; S. J. Judd



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


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



Nitrification treatment of swine wastewater with acclimated nitrifying sludge immobilized in polymer pellets  

SciTech Connect

Nitrification of ammonia (NH{sub 4}{sup +}) is a critical component for improved systems of animal wastewater treatment. One of the most effective processes uses nitrifying microorganisms encapsulated in polymer resins. It is used in Japan in municipal wastewater treatment plants for higher nitrification rates, shorter hydraulic retention times (HRT), and lower aeration treatment cost. The authors evaluated whether this technology could be adapted for treatment of higher-strength lagoon swine wastewaters containing {approximately}230 mg NH{sub 4}-N/L and 195 mg BOD{sub 5}/L. A culture of acclimated lagoon nitrifying sludge (ALNS) was prepared from a nitrifying biofilm developed in an overland flow soil using fill-and-draw cultivation. The ALNS was successfully immobilized in 3- to 5-mm polyvinyl alcohol (PVA) polymer pellets by a PVA-freezing method. Swine wastewater was treated in aerated, suspended bioreactors with a 15% (w/v) pellet concentration using batch and continuous flow treatment. Alkalinity was supplemented with inorganic carbon to maintain the liquid pH within an optimum range (7.7--8.4). In batch treatment, only 14 h were needed for nitrification of NH{sub 4}{sup +}. Ammonia was nitrified readily, decreasing at a rate of 16.1 mg NH{sub 4}-N/L h. In contrast, it took 10 d for a control (no-pellets) aerated reactor to start nitrification; furthermore, 70% of the N was lost by air stripping. Without alkalinity supplements, the pH of the liquid fell to 6.0--6.2, and NH{sub 4}{sup +} oxidation stopped. In continuous flow treatment, nitrification efficiencies of 95% were obtained with NH{sub 4}{sup +} loading rates of 418 mg-N/L-reactor d (2.73 g-N/g-pellet d) and an HRT of 12 h. The rate of nitrification obtained with HRT of 4 h was 567 mg-N/L d. In all cases, the NH{sub 4}-N removed was entirely recovered in oxidized N forms. Nitrification rates obtained in this work were not greatly affected by high NH{sub 4}{sup +} or BOD concentration of swine wastewater. Thus, immobilized pellet technology can be adapted for fast and efficient removal of NH{sub 4}{sup +} contained in anaerobic swine lagoons using acclimated microorganisms.

Vanotti, M.B.; Hunt, P.G.



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

SciTech Connect

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.

Hullenbusch, Eric van [Laboratoire des Geomateriaux, Universite de Marne la Vallee (France); Farges, Francois [Dept. of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 (United States); USM 201 'Mineralogie', UMR CNRS 7160, Museum National d'Histoire Naturelle, Paris, (France); Lenz, Markus; Lens, Piet [Sub-dept. of Environmental Technology, Wageningen Universitaet, 6700 EV Wageningen (Netherlands); Brown, Gordon E. Jr. [Dept. of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 (United States); Stanford Synchrotron Radiation Laboratory, SLAC, MS 69, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)



Demonstration of vitrification of surrogate F006 waste-water treatment sludges  

SciTech Connect

A demonstration program with the focus on vitrification of surrogate formulations of Savannah River Site M-Area wastewater treatment sludges has been completed. The program utilized commercially available melting equipment, supplied by EnVitCo, Inc., and Stir Melter, Inc., located at the Clemson University Environmental Systems Engineering Laboratories. Over 2000 kg of glass was manufactured in a series of five separate tests with four formulations. Glasses were characterized by Toxicity Characteristic Leaching Procedure (TCLP) and the Product Consistency Test (PCT), with all glasses showing leach characteristics better than Land Disposal Requirements (LDR) for corresponding F006 waste (TCLP) and benchmark environmental assessment glasses (PCT). Offgas sampling by EPA Method 5 was conducted, including chemical analysis of filter residue and impinger solution. Data is presented on glass leaching, offgas sampling, phase separation, and melter performance.

Bennert, D.M.; Overcamp, T.J. [Clemson Univ. Environmental Systems Engineering, Anderson, SC (United States); Bickford, D.F.; Jantzen, C.M.; Cicero, C.A. [Westinghouse Savannah River Co., Aiken, SC (United States)



XRF and leaching characterization of waste glasses derived from wastewater treatment sludges  

SciTech Connect

Purpose of this study was to investigate use of XRF (x-ray fluorescence spectrometry) as a near real-time method to determine melter glass compositions. A range of glasses derived from wastewater treatment sludges associated with DOE sites was prepared. They were analyzed by XRF and wet chemistry digestion with atomic absorption/inductively coupled emission spectrometry. Results indicated good correlation between these two methods. A rapid sample preparation and analysis technique was developed and demonstrated by acquiring a sample from a pilot-scale simulated waste glass melter and analyzing it by XRF within one hour. From the results, XRF shows excellent potential as a process control tool for waste glass vitrification. Glasses prepared for this study were further analyzed for durability by toxicity characteristic leaching procedure and product consistency test and results are presented.

Ragsdale, R.G., Jr



Characterization and biofiltration of a real odorous emission from wastewater treatment plant sludge.  


Biofilters have been widely employed for the treatment of malodorous emissions from sludge handling activities in wastewater treatment plants (WWTPs), although their optimized design has been usually hindered by the lack of information about the dynamics of odorant formation. Besides, the odour abatement efficiency of biofilters has been rarely assessed on an individual odorant elimination basis. In this context, the characterization of odours from WWTP sludge in this study revealed the occurrence of a wide range of chemicals, including reduced sulphur compounds and volatile organic compounds (VOCs), with a dynamic concentration profile. The abatement of these odorants was evaluated in a compost-based biofilter at different empty bed residence times (EBRTs). Removal efficiencies (REs) higher than 99% were recorded for limonene, ketones and benzene, while toluene and DMTS REs exceeded 80% at an EBRT of 60 s. A stable biofilter performance was recorded despite the inlet odorant concentration fluctuations. Conversely, DMS and acetic acid were poorly removed due to their likely formation within the biofilter packing material. No correlation between the odorant elimination efficiency and their individual partition coefficients was herein observed. PMID:23291041

Lebrero, Raquel; Rangel, M Gabriela L; Muñoz, Raúl



Selective hydrolysis of wastewater sludge Part 1, December 2008  

E-print Network

Report Selective hydrolysis of wastewater sludge Part 1, December 2008 Revised Model calculations and cost benefit analysis for Esbjerg Vest wastewater treatment plant, Denmark PSO-F&U project nr. 2006 This project "Selective hydrolysis of wastewater sludge" is supported by EnergiNet .DK under the PSO


Selective hydrolysis of wastewater sludge Part 1, September 2007  

E-print Network

Report Selective hydrolysis of wastewater sludge Part 1, September 2007 Model calculations and cost "Selective hydrolysis of wastewater sludge" is supported by EnergiNet.DK under the PSO-F&U projects having National Laboratory, Rambøll, the Estate of Overgaard and SamRas. The wastewater treatment plant Esbjerg


6:2 Fluorotelomer alcohol aerobic biotransformation in activated sludge from two domestic wastewater treatment plants.  


6:2 Fluorotelomer alcohol [6:2 FTOH, F(CF2)6CH2CH2OH] is a major basic chemical being used to manufacture FTOH-based products. After the end of use, 6:2 FTOH-based products may be released to domestic wastewater treatment plants (WWTPs) as a first major environmental entry point. Activated sludge collected from two WWTPs was dosed with 6:2 FTOH to investigate its biotransformation rate and to identify major transformation products. The volatile 5:2 sFTOH [F(CF2)5CH(OH)CH3] is the most abundant transformation product and accounted for an average of 40mol% of initially dosed 6:2 FTOH after two months of incubation with activated sludge, with 30mol% detected in the headspace. PFPeA [F(CF2)4COOH] averaged 4.4mol% after two months, 2.4-7 times lower than that in sediment and soils. The much lower level of PFPeA formed in activated sludge compared with soil indicates that microbial populations in activated sludge may lack enzymes or suitable environment conditions to promote rapid 5:2 sFTOH decarboxylation to form PFPeA, resulting in more 5:2 sFTOH partitioned to the headspace. PFHxA [F(CF2)5COOH] and 5:3 [F(CF2)5CH2CH2COOH] acid are major non-volatile transformation products in activated sludge. For example, PFHxA averaged 11mol% after two months, which is about 30% higher compared with sediment and soils, suggesting that microbes in WWTPs may utilize similar pathways as that in sediment and soils to convert 5:2 sFTOH to PFHxA. 5:3 Acid averaged 14mol% after two months, comparable to that in soils and slightly lower than in sediment, further confirming that 5:3 acid is a unique product of 6:2 FTOH biotransformation in the environment. PMID:23540810

Zhao, Lijie; McCausland, Patricia K; Folsom, Patrick W; Wolstenholme, Barry W; Sun, Hongwen; Wang, Ning; Buck, Robert C



Combined Treatment of Leachate from Sanitary Landfill and Municipal Wastewater by Activated Sludge  

Microsoft Academic Search

Two leachates from sanitary landfill, characterized by different biodegradability, were mixed with municipal wastewater in different proportions and aerobically treated by activated sludge. The overall removals of chemical oxygen demand (COD) and am- monia as well as the fraction of hardly-biodegradable substances were investigated to se- lect the best operating conditions for the simultaneous removal of these pollutants. Pre- liminary

A. Del Borghi; L. Binaghi; A. Converti; M. Del Borghi


Molecular characterization of activated sludge from a seawater-processing wastewater treatment plant  

PubMed Central

Summary The prokaryotic community composition of activated sludge from a seawater?processing wastewater treatment plant (Almeria, Spain) was investigated by using the rRNA approach, combining different molecular techniques such as denaturing gradient gel electrophoresis (DGGE), clone libraries and in situ hybridization (FISH and CARD?FISH). Most of the sequences retrieved in the DGGE and the clone libraries were similar to uncultured members of different phyla. The most abundant sequence recovered from Bacteria in the clone library corresponded to a bacterium from the Deinococcus–Thermus cluster (almost 77% of the clones), and the library included members from other groups such as the Alpha, Gamma and Delta subclasses of Proteobacteria, the Bacteroidetes and Firmicutes. Concerning the archaeal clone library, we basically found sequences related to different orders of methanogenic Archaea, in correspondence with the recovered DGGE bands. Enumeration of DAPI (4?,6?diamidino?2?phenylindole) stained cells from two different activated sludge samples after a mechanical flocculation disruption revealed a mean cell count of 1.6?×?109?ml?1. Around 94% of DAPI counts (mean value from both samples) hybridized with a Bacteria specific probe. Alphaproteobacteria were the dominant bacterial group (36% of DAPI counts), while Beta?, Delta? and Gammaproteobacteria, Bacteroidetes, Actinobacteria and Firmicutes contributed to lower proportions (between 0.5–5.7% of DAPI counts). Archaea accounted only for 6% of DAPI counts. In addition, specific primers for amplification of the amoA (ammonia monooxygenase) gene were used to detect the presence of Beta, Gamma and archaeal nitrifiers, yielding positive amplifications only for Betaproteobacteria. This, together with negative in situ hybridizations with probes for well?known nitrifiying bacteria, suggests that nitrification is performed by still undetected microorganisms. In summary, the combination of the three approaches provided different and complementary pictures of the real assemblage composition and allowed to get closer to the main microorganisms involved in key processes of seawater?processing activated sludge. PMID:21414181

Sanchez, Olga; Garrido, Laura; Forn, Irene; Massana, Ramon; Maldonado, Manuel Ignacio; Mas, Jordi



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


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



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



Bioavailable and biodegradable dissolved organic nitrogen in activated sludge and trickling filter wastewater treatment plants.  


A study was carried out to understand the fate of biodegradable dissolved organic nitrogen (BDON) and bioavailable dissolved organic nitrogen (ABDON) along the treatment trains of a wastewater treatment facility (WWTF) equipped with an activated sludge (AS) system and a WWTF equipped with a two-stage trickling filter (TF) process. A mixed culture bacterial inoculum was used for BDON determination, while a pure cultured algal inoculum (Selenastrum capricornutum) and a combination of the bacterial and alga inocula were used for ABDON determination. Results show that BDON and ABDON varied significantly within the treatment facility and between the two facilities. From after primary clarification to final effluent, the TF facility removed 65% of BDON and 63% of ABDON while the AS facility removed 68% of BDON and 56% of ABDON. For the TF facility, BDON and ABDON were 62% and 71% of the effluent dissolved organic nitrogen (DON), while they were 26% and 47% of the effluent DON for the AS WWTF. BDON and ABDON results, which are based on incubation of samples under different inocula (bacteria only, algae only, and bacteria + algae), further showed that some portions of DON are utilizable by bacteria only or algae only while there is a portion of DON utilizable by either bacteria or algae. DON utilization was the highest when both bacteria and algae were used as a co-inoculum in the samples. This study is the first to investigate the fate of BDON and ABDON along the treatment trains of two different WWTFs. PMID:23579086

Simsek, Halis; Kasi, Murthy; Ohm, Jae-Bom; Blonigen, Mark; Khan, Eakalak



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


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



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


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



Fate and behaviour of copper and zinc in secondary biological wastewater treatment processes: II. Removal at varying sludge age.  


The mechanisms for the removal of heavy metals during secondary biological treatment of wastewater, with particular emphasis on the activated sludge process, are considered. It is concluded that the predominant mechanism is the entrapment and co-settlement of insoluble metal species in the mixed liquor (biomass). Secondary extracellular polymeric materials, particularly extracellular polysaccharides and other capsule-forming materials, may also play a role. In general, removal of both copper and zinc was superior at the higher sludge ages employed in this study, 4.3 and 8 days, and can in part be attributed to the superior removals of both biochemical oxygen demand and effluent suspended solids achieved at these sludge ages compared with the lowest sludge age studied, 3.6 days. For both copper and zinc there is an increase in soluble metal across the activated sludge process. However, significant removal of both metals occurs as a consequence of the removal of substantial amounts of insoluble metal. The presence of returned sludge liquors, high in settleable solids, to the mixed liquor appears to moderately enhance the percentage removal of copper and zinc. Membranes used in place of secondary sedimentation also enhance removal of both metals by reducing effluent suspended solids. It is concluded that there is potential for maximizing metal removal by optimization of secondary biological treatment in a sustainable manner, without recourse to energy-intensive or chemically-dependent tertiary treatment technologies. PMID:20586235

Santos, A; Barton, P; Cartmell, E; Coulon, F; Crane, R S; Hillis, P; Lester, J N; Stephenson, T; Judd, S J



Mesophilic anaerobic digestion of waste activated sludge: influence of the solid retention time in the wastewater treatment process  

Microsoft Academic Search

The performance of mesophilic anaerobic digesters of four large Italian wastewater treatment plants without primary sedimentation were studied. Only the waste activated sludge is stabilised by means of the mesophilic (35–37°C) anaerobic digestion process. The anaerobic digesters generally worked with a hydraulic retention time in a range of 20–40 days and an organic loading rate of some 1kgVS\\/mreactor3day. The solids

David Bolzonella; Paolo Pavan; Paolo Battistoni; Franco Cecchi



Studies on the Survival of Enterohemorrhagic and Environmental Escherichia coli Strains in Wastewater and in Activated Sludges from Dairy Sewage Treatment Plants  

Microsoft Academic Search

Survival of Escherichia coli O157:H7 strain isolated from milk in Poland and an environmental E. coli strain in wastewater from Garwolin and £owicz dairies and in activated sludges from dairy sewage treatment plants as well as in dairy wastewater with activated sludges was examined. Environmental materials were contaminated with about 10 8 of target bacteria\\/ml of sample. The experiments were



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


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



Taxonomic relatedness shapes bacterial assembly in activated sludge of globally distributed wastewater treatment plants.  


Activated sludge (AS), which has been in use for 100 years, has been the most popular biological process in various wastewater treatment plants (WWTPs), in which bacteria plays central roles in pollutant removal. However, the potential relationship between bacteria taxa and the niches occupied by specific functional bacteria in AS are largely unknown. Here, correlation-based network analysis was applied to a 16S rRNA gene pyrosequencing dataset containing >?760?000 sequences of 50?AS samples from globally distributed full-scale WWTPs. The results showed that (i) bacterial assembly in AS was nonrandomly arranged by taxonomic relatedness and (ii) intra- and inter-phylum/class co-occurrence higher than expected by chance was induced by multiple deterministic processes, such as habitat filtering and competition. Moreover, based on bacterial occupancy, a prevalent core set of cosmopolitan functional bacteria (e.g. multiple nitrogen-cycling-related bacteria) was widely distributed in the AS of different WWTPs, showing strong ecological associations among them. Additionally, the AS network has statistical and structural characteristics similar to those of previously reported ecological networks, such as power-law connectivity distribution and nonrandomly connected properties. Overall, this work provides novel insights into the bacterial associations within AS and sheds light on the ecological rules guiding bacterial assembly in WWTPs. PMID:24329969

Ju, Feng; Xia, Yu; Guo, Feng; Wang, Zhiping; Zhang, Tong



Fate of Zinc Oxide Nanoparticles during Anaerobic Digestion of Wastewater and Post-Treatment Processing of Sewage Sludge  

SciTech Connect

The rapid development and commercialization of nanomaterials will inevitably result in the release of nanoparticles (NPs) to the environment. As NPs often exhibit physical and chemical properties significantly different from those of their molecular or macrosize analogs, concern has been growing regarding their fate and toxicity in environmental compartments. The wastewater-sewage sludge pathway has been identified as a key release pathway leading to environmental exposure to NPs. In this study, we investigated the chemical transformation of two ZnO-NPs and one hydrophobic ZnO-NP commercial formulation (used in personal care products), during anaerobic digestion of wastewater. Changes in Zn speciation as a result of postprocessing of the sewage sludge, mimicking composting/stockpiling, were also assessed. The results indicated that 'native' Zn and Zn added either as a soluble salt or as NPs was rapidly converted to sulfides in all treatments. The hydrophobicity of the commercial formulation retarded the conversion of ZnO-NP. However, at the end of the anaerobic digestion process and after postprocessing of the sewage sludge (which caused a significant change in Zn speciation), the speciation of Zn was similar across all treatments. This indicates that, at least for the material tested, the risk assessment of ZnO-NP through this exposure pathway can rely on the significant knowledge already available in regard to other 'conventional' forms of Zn present in sewage sludge.

Lombi, Enzo; Donner, Erica; Tavakkoli, Ehsan; Turney, Terence W.; Naidu, Ravi; Miller, Bradley W.; Scheckel, Kirk G. (U. South Australia); (EPA); (Monash)



Recovery of Iron Coagulants From Tehran Water-Treatment-Plant Sludge for Reusing in Textile Wastewater Treatment  

Microsoft Academic Search

Most of the water treatment plants in Iran discharge their sludge to the environment whithout consideration of possible side effects. Since this kind of sludge is generally considered pollutant, the sludge treatment of water industry seems to be an essential task. Obviously theweight and volume of solids produced during the coagulation process are much more than other wastes of water

F Vaezi; F Batebi; Gh Moosavi


Fate and effect of naphthenic acids on oil refinery activated sludge wastewater treatment systems.  


Naphthenic acids (NAs) are a complex group of alkyl-substituted acyclic, monocyclic and polycyclic carboxylic acids present in oil sands process waters, crude oil, refinery wastewater and petroleum products. Crude oil, desalter brine, influent, activated sludge mixed liquor and effluent refinery samples were received from six United States refineries. The total acid number (TAN) of the six crudes tested ranged from 0.12 to 1.5 mg KOH/g crude oil and correlated to the total NA concentration in the crudes. The total NA concentration in the desalter brine, influent, activated sludge mixed liquor and effluent samples ranged from 4.2 to 40.4, 4.5 to 16.6, 9.6 to 140.3 and 2.8 to 11.6 mg NA/L, respectively. The NAs in all wastewater streams accounted for less than 16% of the total COD, indicating that many other organic compounds are present and that NAs are a minor component in refinery wastewaters. Susceptibility tests showed that none of the activated sludge heterotrophic microcosms was completely inhibited by NAs up to 400 mg/L. Growth inhibition ranging from 10 to 59% was observed in all microcosms at and above 100 mg NA/L. NAs chronically-sorbed to activated sludge mixed liquor biomass and powdered activated carbon (PAC) were recalcitrant and persistent. More than 80% of the total NAs remained in the solid phase at the end of the 10-day desorption period (five successive desorption steps). Throughout a 90-day incubation period, the total NA concentration decreased by 33 and 51% in PAC-free and PAC-containing mixed liquor microcosms, respectively. The lower molecular weight fraction of NAs was preferentially degraded in both mixed liquors. The persistence of the residual, higher molecular weight NAs is likely a combination of molecular recalcitrance and decreased bioavailability when chronically-sorbed to the biomass and/or PAC. PMID:23141768

Misiti, Teresa; Tezel, Ulas; Pavlostathis, Spyros G



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


Wastewater treatment  

SciTech Connect

The processes presently used for industrial wastewater treatment are shown. This article presents an overview of the wastewaters and the processes, and then describes each process in detail, explaining how it works, what it can accomplish, and how it should be applied. Costs are also discussed. The authors explain how a combination of wastewaters can be economically treated so as to meet effluent limits.

Eckenfelder, W.W.; Patoczka, J.; Watkin, A.T.



Phylogenetic and functional diversity of metagenomic libraries of phenol degrading sludge from petroleum refinery wastewater treatment system  

PubMed Central

In petrochemical refinery wastewater treatment plants (WWTP), different concentrations of pollutant compounds are received daily in the influent stream, including significant amounts of phenolic compounds, creating propitious conditions for the development of particular microorganisms that can rapidly adapt to such environment. In the present work, the microbial sludge from a refinery WWTP was enriched for phenol, cloned into fosmid vectors and pyrosequenced. The fosmid libraries yielded 13,200 clones and a comprehensive bioinformatic analysis of the sequence data set revealed a complex and diverse bacterial community in the phenol degrading sludge. The phylogenetic analyses using MEGAN in combination with RDP classifier showed a massive predominance of Proteobacteria, represented mostly by the genera Diaphorobacter, Pseudomonas, Thauera and Comamonas. The functional classification of phenol degrading sludge sequence data set generated by MG-RAST showed the wide metabolic diversity of the microbial sludge, with a high percentage of genes involved in the aerobic and anaerobic degradation of phenol and derivatives. In addition, genes related to the metabolism of many other organic and xenobiotic compounds, such as toluene, biphenyl, naphthalene and benzoate, were found. Results gathered herein demonstrated that the phenol degrading sludge has complex phylogenetic and functional diversities, showing the potential of such community to degrade several pollutant compounds. This microbiota is likely to represent a rich resource of versatile and unknown enzymes which may be exploited for biotechnological processes such as bioremediation. PMID:22452812



Aerobic granular sludge formation for high strength agro-based wastewater treatment.  


The present study investigates the formation of aerobic granular sludge in sequencing batch reactor (SBR) fed with palm oil mill effluent (POME). Stable granules were observed in the reactor with diameters between 2.0 and 4.0mm at a chemical oxygen demand (COD) loading rate of 2.5 kg COD m(-3) d(-1). The biomass concentration was 7600 mg L(-1) while the sludge volume index (SVI) was 31.3 mL g SS(-1) indicating good biomass accumulation in the reactor and good settling properties of granular sludge, respectively. COD and ammonia removals were achieved at a maximum of 91.1% and 97.6%, respectively while color removal averaged at only 38%. This study provides insights on the development and the capabilities of aerobic granular sludge in POME treatment. PMID:21524907

Abdullah, Norhayati; Ujang, Zaini; Yahya, Adibah



Ion exchange extraction of heavy metals from wastewater sludges.  


Heavy metals are common contaminants of some industrial wastewater. They find their way to municipal wastewaters due to industrial discharges into the sewerage system or through household chemicals. The most common heavy metals found in wastewaters are lead, copper, nickel, cadmium, zinc, mercury, arsenic, and chromium. Such metals are toxic and pose serious threats to the environment and public health. In recent years, the ion exchange process has been increasingly used for the removal of heavy metals or the recovery of precious metals. It is a versatile separation process with the potential for broad applications in the water and wastewater treatment field. This article summarizes the results obtained from a laboratory study on the removal of heavy metals from municipal wastewater sludges obtained from Ardhiya plant in Kuwait. Data on heavy metal content of the wastewater and sludge samples collected from the plant are presented. The results obtained from laboratory experiments using a commercially available ion exchange resin to remove heavy metals from sludge were discussed. A technique was developed to solubilize such heavy metals from the sludge for subsequent treatment by the ion exchange process. The results showed high efficiency of extraction, almost 99.9%, of heavy metals in the concentration range bound in wastewater effluents and sludges. Selective removal of heavy metals from a contaminated wastewater/sludge combines the benefits of being economically prudent and providing the possibility of reuse/recycle of the treated wastewater effluents and sludges. PMID:15027828

Al-Enezi, G; Hamoda, M F; Fawzi, N



A nationwide survey and emission estimates of cyclic and linear siloxanes through sludge from wastewater treatment plants in Korea.  


Siloxanes are widely used in various industrial applications as well as in personal care products. Despite their widespread use and potential toxic effects, few studies have reported on the occurrence of siloxanes in the environment. In this study, we determined the concentrations of 5 cyclic and 15 linear siloxanes in sludge collected from 40 representative wastewater treatment plants (WWTPs) in Korea. Total concentrations of 20 siloxanes (?siloxane) in sludge ranged from 0.05 to 142 (mean: 45.7) ?g/g dry weight, similar to the concentrations reported in European countries but higher than those reported in China. The concentrations of siloxanes in sludge from domestic WWTPs were significantly (p<0.01) higher than those from industrial WWTPs, indicating higher consumption of siloxanes in various personal care products (e.g. shampoos and conditioners). The major siloxane compounds found in sludge were decamethylcyclopentasilane (D5), docosamethyldecasiloxane (L10) and dodecamethylcyclohexasilane (D6), which collectively accounted for, on average, 62% of the ?siloxane concentrations. Non-parametric multidimensional scaling ordination of the profiles of siloxanes indicated the existence of different usage patterns of siloxanes between industrial and household activities. Multiple linear regression analysis of siloxane concentrations and WWTP characteristics suggested that D5, D6 and linear siloxane concentrations in sludge were positively correlated with population served by a WWTP. Environmental emission fluxes of cyclic and linear siloxanes through sludge disposal in Korea were 14,800 and 18,500kg/year, respectively. This is the first report describing occurrence and environmental emission of siloxanes through sludge in Korea. PMID:25127445

Lee, Sunggyu; Moon, Hyo-Bang; Song, Geum-Ju; Ra, Kongtae; Lee, Won-Chan; Kannan, Kurunthachalam



The role of stress agents as operating factors in formation and functioning of granular aerobic activated sludge at model domestic wastewater treatment.  


Maintenance of the wastewater treatment plants and increasing the efficiency of existing aerobic biological reactors depend on the stability of activated sludge characteristics under varying wastewater parameters within significant limits and/or influence of some environmental factors. The steady microbial communities observed in biofilms and anaerobic granules of activated sludge can serve as successful samples of formation of the similar aerobic systems. The granular aerobic sludge obtained in the course of our researches is an ideal "plant" on treatment of biogenic pollution at both low and high concentrations. It demonstrates high ability for treatment and stability to adverse factors. To improve aerobic wastewater treatment characteristics, a possibility of using impact of stress conditions upon activated sludge has been studied. Under conditions of fractional hydrogen peroxide addition at diffused lighting, the granular aerobic activated sludge adapted to hydrogen peroxide has been obtained. This sludge has got good sedimentary properties and it differs from the control sample in the species diversity, improved treatment characteristics and also resistance to the stressor. It also endures an impact of one-time hydrogen peroxide addition up to 1.2-1.5 g H2O2/l. The conditions under which the steady aerobic granules of the diameter from 2 to 5 mm were formed with high treatment ability have been chosen. The granules were being stabilized at passages with hydrogen peroxide treatment and they endured up to 2.4-3.0 g/l of one-time H2O2 addition. PMID:24556977

Khokhlachev, Nikolay S; Kalenov, Sergei V; Zanina, Olga S; Tyupa, Dmitry V; Baurina, Marina M; Kuznetsov, Alexander Ye



Multi-scale modelling of bioreactor-separator system for wastewater treatment with two-dimensional activated sludge floc dynamics.  


A simple "first generation" multi-scale computational model of the formation of activated sludge flocs at micro-scale and reactor performance at macro-scale is proposed. The model couples mass balances for substrates and biomass at reactor scale with an individual-based approach for the floc morphology, shape and micro-colony development. Among the novel model processes included are the group attachment/detachment of micro-flocs to the core structure and the clustering of nitrifiers. Simulation results qualitatively describe the formation of micro-colonies of ammonia and nitrite oxidizers and the extracellular polymeric substance produced by heterotrophic microorganisms, as typically observed in fluorescence in situ hybridization images. These results are the first step towards realistic multi-scale multispecies models of the activated sludge wastewater treatment systems and a generic modelling strategy that could be extended to other engineered biological systems. PMID:24246170

Ofi?eru, Irina D; Bellucci, Micol; Picioreanu, Cristian; Lavric, Vasile; Curtis, Thomas P



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


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



Hungry microbes eat away wastewater sludge problem  

SciTech Connect

Accumulations of diluted resin solids and sludge in an equalization pond were reducing a White City, Ore., chemical plant`s wastewater treatment capacity by 90%. Dyno Polymers, a division of Norway-based Dyno Industries, manufacturers formaldehyde, urea-formaldehyde and phenol-formaldehyde resins for the wood products industry. High-solids and biosolids bulking in the plant`s aeration pond overloaded the clarifier, and an overabundance of solids in the excess-wastewater holding pond made pumping nearly impossible. The plant`s drains carry production wastewater, truck washout water and equipment rinsewater flows to a central sump. The wastewater is pumped to the facility`s biological treatment system, where it enters an equalization pond and flows to an aeration pond equipped with two 50-horsepower aerators. The water then flows to a clarifier, where solids are settled out and removed before the water is reused or discharged to a public sewer system.

Kratch, K.




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...


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




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...


Quorum quenching bacteria isolated from the sludge of a wastewater treatment plant and their application for controlling biofilm formation.  


Bacteria recognize changes in their population density by sensing the concentration of signal molecules, N-acyl-homoserine lactones (AHLs). AHL-mediated quorum sensing (QS) plays a key role in biofilm formation, so the interference of QS, referred to as quorum quenching (QQ), has received a great deal of attention. A QQ strategy can be applied to membrane bioreactors (MBRs) for advanced wastewater treatment to control biofouling. To isolate QQ bacteria that can inhibit biofilm formation, we isolated diverse AHL-degrading bacteria from a laboratory-scale MBR and sludge from real wastewater treatment plants. A total of 225 AHLdegrading bacteria were isolated from the sludge sample by enrichment culture. To identify the enzyme responsible for AHL degradation in QQ bacteria, AHL-degrading activities were analyzed using cell-free lysate, culture supernatant, and whole cells. Afipia sp. and Acinetobacter sp. strains produced the intracellular QQ enzyme, whereas Pseudomonas sp. and Micrococcus sp. produced the extracellular QQ enzyme that was most likely to produce AHLacylase. AHL-degrading activity was observed in whole-cell assay with the Microbacterium sp. and Rhodococcus sp. strains. There has been no report for AHL-degrading capability in the case of Streptococcus sp. and Afipia sp. strains. Finally, inhibition of biofilm formation by isolated QQ bacteria or enzymes was observed on glass slides and 96-well microtiter plates using crystal violet staining. QQ strains or enzymes not only inhibited initial biofilm development but also reduced established biofilms. PMID:25112313

Kim, A-Leum; Park, Son-Young; Lee, Chi-Ho; Lee, Chung-Hak; Lee, Jung-Kee



Coagulation\\/flocculation process and sludge conditioning in beverage industrial wastewater treatment  

Microsoft Academic Search

Attempts were made in this study to examine the effectiveness of coagulation and flocculation process using ferric chloride and polyelectrolyte (non-ionic polyacrylamide) for the treatment of beverage industrial wastewater. Removal of organic matter (expressed as chemical oxygen demand, COD), total phosphorus (TP) and total suspended solid (TSS) using ferric chloride and organic polyelectrolyte during coagulation\\/flocculation process were investigated. Also, the

O. S. Amuda; I. A. Amoo



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



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.



Application of sludge from urban wastewater treatment plants in road's embankments.  


While different kinds of compost have been tested for highway revegetation, sewage sludge has only been used for agricultural purposes. In this work, its application for helping vegetation establishment on roads embankments is studied. Testing areas measuring 4x5m were constructed on a new highway embankment in an arid location. Several variables are analyzed: side slope (2); sludge dosage (4); vegetative species (4). Results are presented on growth, survival rate and germination of the plants; colonization of other species; cover crop for the plots; estimation of the erosion. The species planted manually showed satisfactory results although any variable was specially significant in this case. However, in relation to the species planted using hydroseeding, 2:1 side slope presented better results than 3:2 side slope. Using hydroseeding, the performance of different species was significantly different, thyme did not grow if sludge was not applied and the cover crop was higher in plots with 3:2 side slope than in plots with 2:1 side slope, essentially due to the presence of colonizing species. Finally, the costs of the proposed treatments are figured out, being concluded that, so much from the technical as the economic point of view, it is a viable proposal for sewage sludge management. PMID:16233951

De Oña, J; Osorio, F



Investigation of nonylphenol and nonylphenol ethoxylates in sewage sludge samples from a metropolitan wastewater treatment plant in Turkey.  


Nonylphenol ethoxylates (NPEOs) have drawn significant attention within the last decade for both scientific and legislative reasons. In Turkey, the Regulation Regarding the Use of Domestic and Urban Sludges on Land states a limit value for the sum of nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenol diethoxylate (NP2EO) as NPE (NPE=NP+NP1EO+NP2EO). Unfortunately a standard method for the determination of these chemicals has not been yet set by the authorities and no data exists about the concentrations of NP and NPEOs in sewage sludge in Turkey. The aim of this study is to propose simple and easily applicable extraction and measurement techniques for 4-n-nonylphenol (4-n-NP), NP, NP1EO and NP2EO in sewage sludge samples and investigate the year round concentrations in a Metropolitan Wastewater Treatment Plant (WWTP) in Turkey. Different extraction techniques and GC/MS methods for sewage sludge were tested. The best extraction method for these compounds was found to be ultrasonication (5min) using acetone as the solvent with acceptable recovery of analytes suggested by USEPA and other studies. The optimized extraction method showed good repeatability with relative standard deviations (RSDs) less than 6%. The recovery of analytes were within acceptable limits suggested by USEPA and other studies. The limits of detection (LODs) were 6µgkg(-1) for NP and NP1EO, 12µgkg(-1) for NP2EO and 0.03µgkg(-1) for 4-n-NP. The developed method was applied to sewage sludge samples obtained from the Central WWTP in Ankara, Turkey. The sum NPE (NP+NP1EO+NP2EO) was found to be in between 5.5µgkg(-1) and 19.5µgkg(-1), values which are in compliance with Turkish and European regulations. PMID:25281154

Omero?lu, Seçil; Kara Murdoch, Fadime; Dilek Sanin, F



Effects of sonication on bacteria viability in wastewater treatment plants evaluated by flow cytometry—Fecal indicators, wastewater and activated sludge  

Microsoft Academic Search

The application of sonication to wastewater or sludge contributes to the dispersion of aggregates, the solubilisation of particulate matter with an increase in its biodegradability, the damage of microorganisms due to the loss of cellular membrane integrity. This research is aimed at investigating the effects of sonication at 20kHz frequency on viability of microorganisms present in raw wastewater and activated

Paola Foladori; Bruni Laura; Andreottola Gianni; Ziglio Giuliano



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.



Occurrence and distribution of organophosphate flame retardants/plasticizers in wastewater treatment plant sludges from the Pearl River Delta, China.  


Organophosphate esters (OPs) are widely used as flame retardants or plasticizers and are ubiquitously distributed in the environment. In the present study, the occurrence and distribution of 7 widely used OPs were analyzed in sludge samples collected from 19 municipal wastewater treatment plants in the Pearl River Delta, South China. All analytes were detected in these samples, and the total concentration of OPs ranged from 96.7 µg/kg to 1312.9 µg/kg dry weight, with a mean value of 420.1 µg/kg dry weight. In most sludge samples OPs exhibited a similar distribution pattern, for example, tris(2-butoxyethyl) phosphate (TBEP) and triphenyl phosphate (TPhP) were identified as the dominant compounds. However, the results also indicated significantly higher levels of OPs in specific sludges, such as tri-n-butyl phosphate (804.9 µg/kg), TBEP (783.7 µg/kg), TPhP (656.7 µg/kg), and tritolyl phosphate (265.0 µg/kg), which implied different discharge sources in the studied areas. PMID:24729049

Zeng, Xiangying; He, Lixiong; Cao, Shuxia; Ma, Shengtao; Yu, Zhiqiang; Gui, Hongyan; Sheng, Guoying; Fu, Jiamo



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


Differential filtration was used to measure silver (>2 nm) entering and leaving nine sewage treatment plants (STPs). The mean concentration of colloidal (2-450 nm) silver, which includes nanosilver, was found to be 12 ng L(-1) in the influent and 6 ng L(-1) in the effluent. For particulate silver (>450 nm) the mean values were 3.3 ?g L(-1) for influent and 0.08 ?g L(-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 3-14 mg kg(-1) DW in the sludge (median 3.6), which if the sludge were added at the recommended rate to soil, would add 11 ?g kg(-1) yr(-1) to the top 20 cm soil layer. Predicted concentrations using the LF2000-WQX model for all the rivers of England and Wales for nanosilver were typically in the 0-1 ng L(-1) range but levels up to 4 ng L(-1) are possible in a high discharge and low flow scenario. Predicted concentrations for the total particulate forms were mostly below 50 ng L(-1) except for a high discharge and low flow scenario where concentrations could reach 135 ng L(-1). PMID:25048887

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



Treatment of tomato processing wastewater by an upflow anaerobic sludge blanket-anoxic-aerobic system.  


The main objective of this study is to assess the achievability of stringent discharge criteria i.e. BOD(5)<15 mg/L, TSS<15 mg/L and NH(4)-N<1mg/L during the treatment of tomato processing wastewater with COD of 2800-15,500 mg/L, BOD(5) of 1750-7950 mg/L, TKN of 48-340 mg/L and NH(4)-N of 21-235 mg/L. Two treatment systems, a UASB-aerobic system and a UASB-anoxic-aerobic system were tested. Furthermore due to alkalinity deficiency, in the raw wastewater, the study explored varying UASB effluent recirculation flowrates to the UASB influent to reduce additional alkalinity requirements. The UASB-anoxic-aerobic system was effective in treating tomato canning wastewater at an overall HRT of 1.75 days while achieving 98.5% BOD(5), 95.6% COD, 84% TSS and 99.5% NH(4)-N removal producing effluent BOD(5), COD, TSS, NH(4)-N, TKN, NO(2)-N, NO(3)-N and PO(4)-P of 10, 70, 15, 0.5, 3, 0, 60 and 4 mg/L, respectively. The biogas yield was 0.43 m(3)/kg COD removed. PMID:16275063

Gohil, Alpesh; Nakhla, George



Hybrid activated sludge/biofilm process for the treatment of municipal wastewater in a cold climate region: a case study.  


A hybrid activated sludge/biofilm process was investigated for wastewater treatment in a cold climate region. This process, which contains both suspended biomass and biofilm, usually referred as IFAS process, is created by introducing plastic elements as biofilm carrier media into a conventional activated sludge reactor. In the present study, a hybrid process, composed of an activated sludge and a moving bed biofilm reactor was used. The aim of this paper has been to investigate the performances of a hybrid process, and in particular to gain insight the nitrification process, when operated at relatively low MLSS SRT and low temperatures. The results of a pilot-scale study carried out at the Department of Hydraulic and Environmental Engineering at the Norwegian University of Science and Technology in Trondheim are presented. The experimental campaign was divided into two periods. The pilot plant was first operated with a constant HRT of 4.5 hours, while in the second period the influent flow was increased so that HRT was 3.5 hours. The average temperature was near 11.5°C in the overall experimental campaign. The average mixed liquor SRT was 5.7 days. Batch tests on both carriers and suspended biomass were performed in order to evaluate the nitrification rate of the two different biomasses. The results demonstrated that this kind of reactor can efficiently be used for the upgrading of conventional activated sludge plant for achieving year-round nitrification, also in presence of low temperatures, and without the need of additional volumes. PMID:21436546

Di Trapani, Daniele; Christensso, Magnus; Odegaard, Hallvard



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


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



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



Evaluation of waste activated sludge as a coagulant aid for the treatment of industrial wastewater containing mixed surfactants.  


Wastewater generated by the industry manufacturing detergents and various kinds of consumer products normally contains very high contents of mixed surfactants, organic matters expressed as chemical oxygen demand (COD), and phosphates that must be treated prior to discharge to the aquatic environment. In this study, jar-test experiments were conducted to evaluate the waste activated sludge (WAS) as a coagulation aid in the coagulation-flocculation process with ferric chloride or aluminum sulfate as a coagulant for the treatment of wastewater collected from the aforementioned industry. The WAS was selected because of its adsorption capability of anionic surfactants and its availability from the wastage stream of biological wastewater treatment process. The effective dosages of both coagulants with and without the WAS additions were determined in this study. Without the WAS addition, the concentrations of 800 mg/L aluminum sulfate at the optimum pH value of 8 and 2208 mg/L ferric chloride at the optimum pH value of 12 were the optimum chemical dosages. It appears that aluminum sulfate was more effective than ferric chloride based on the chemical dosage and removal efficiency. The turbidity, suspended particles, anionic surfactants, COD, and phosphates removal efficiencies of aluminum sulfate and ferric chloride under the optimum dosage were 95.6, 88.2, 78.4, 73.5, 47.3% and 98.8, 92.0, 72.7, 67.5, 53.1%, respectively. The addition of 200 mg/L WAS was sufficient to reduce the optimum dosages of both chemicals by 200 mg/L. The cationic surfactant existing in the wastewater worked as a flocculating agent leading to the flocculation of waste activated sludge resulting in the enmeshment of the suspended particles and colloids on which the COD, anionic surfactants, and phosphates were adsorbed. However, the substances removal efficiencies of ferric chloride and aluminum sulfate were slightly enhanced and reduced, respectively. It is possibly explained that the settling time is insufficient to settle the aluminum hydroxide floc when it is compared to the ferric hydroxide floc because the iron floc is normally heavier than the alum floc. PMID:19241265

Sriwiriyarat, Tongchai; Jangkorn, Siriprapha



A study of the relationship among sludge retention time, bacterial communities, and hydrolytic enzyme activities in inclined plate membrane bioreactors for the treatment of municipal wastewater.  


Inclined plate membrane bioreactors (ip-MBRs) have been proposed as a highly effective method in wastewater treatment. With the help of settling enhancer inclined plates, dense excess sludge can be kept in the mainstream of the process, and consequently, suitable sludge mass can be maintained in the membrane tank. In this study, the relationship among sludge retention time (SRT), bacterial communities, and hydrolytic enzyme activities was investigated. Two identical bench-scale ip-MBRs were operated 1 year in real municipal wastewater treatment. Multidimensional scaling (MDS) plots of terminal restriction fragment length polymorphism (T-RFLP) fingerprints showed similar changes in the bacterial communities in terms of bacterial members and abundance over time in both the reactors, which was primarily caused by the changes of wastewater composition. However, the impact of SRT revealed significant differences in the dominant bacterial communities when both the reactors were operated with a largely different SRT (infinite SRT and SRT of 20 days). The sequences of bacterial 16S rRNA gene were classified into six libraries of A-F. The largest group of sequences belonged to the phylum Proteobacteria. The phylum Bacteroidetes was dominant in the seed sludge retrieved from the conventional activated sludge (CAS) as Flavobacterium-like bacterium was dominantly observed. Under the MBR operation (libraries B-F), bacterial communities belonging to the phyla Proteobacteria and Chloroflexi were dominant. Most of them may be responsible for protein degradation because aminopeptidase activity increased in proportion with the abundance of these bacteria. PMID:25016344

Ittisupornrat, Suda; Tobino, Tomohiro; Yamamoto, Kazuo



Potential of filter-vermicomposter for household wastewater pre-treatment and sludge sanitisation on site.  


Septic tank systems have been widely used to separate and digest solid matter in the household wastewater for a long time. However, they contaminate groundwater with pathogens and nutrients and deprive agriculture of valuable nutrients and soil conditioner from human excreta. Compared with septic tank systems the filter-composter (Rottebehaelter), which usually consists of an underground monolithic concrete tank having two filter beds at its bottom or two filter bags that are hung side by side and used alternately at intervals of 6-12 months, is an efficient component for solid-liquid separation, pre-treatment and collection/storage of solid matter in household wastewater. The solids are retained and decompose in the filter bags or on the filter bed while the liquid filters through. However, because of the high moisture content of the retained solids decomposition is slow. Therefore, secondary treatment of the retained solids is required for sanitisation. The breakthrough was the combination of vermicomposting with the filter-composter system. Relatively dry and stable retained materials were obtained in the filter bags in about 3 months only. No secondary treatment is required as the human excreta will be converted to vermicastings, which are hygienically safe and can be reused as soil conditioner. Therefore, further development of the filter-composter with vermicomposting is worthwhile, especially the aspects of sanitisation of the faecal matter and its reuse as a soil conditioner. PMID:17506421

Gajurel, D; Deegener, S; Shalabi, M; Otterpohl, R



Self-heating of dried wastewater sludge.  


We experimentally studied the occurrence of spontaneous self-heating of sludge after drying, to understand its nature, course and remediation. The sludge originates from primary and biological treatment of both municipal and industrial wastewater, the latter largely dominant (approx. 90% total organic carbon, mainly from local tanneries). Dried sludge is collected into big-bags (approx. 1.5m(3)) and landfilled in a dedicated site. After several years of regular operation of the landfill, without any management or environmental issue, indications of local warming emerged, together with smoke and smelling emissions, and local subsidence. During a two year monitoring activity, temperatures locally as high as 80°C have been detected, 6-10 m deep. Experiments were carried out on large quantities of dried sludge (? 1t), monitoring the temperature of the samples over long periods of time (months), aiming to reproduce the spontaneous self-heating, under different conditions, to spot enhancing and damping factors. Results demonstrate that air is a key factor to trigger and modulate the self-heating. Water, in addition to air, supports and emphasizes the heating. Unusual drying operation was found to affect dramatically the self-heating activity, up to spontaneous combustion, while ordinary drying conditions yield a sludge with a moderate self-heating inclination. Temperature values as well as heating time scales suggest that the exothermic process nature is mainly chemical and physical, while microbiological activity might be a co-factor. PMID:23046875

Zerlottin, M; Refosco, D; Della Zassa, M; Biasin, A; Canu, P



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


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



Physical-chemical characterization of sludge and granular materials from a vertical flow constructed wetland for municipal wastewater treatment  

E-print Network

constructed wetland for municipal wastewater treatment B. Kim1,2 , M. Gautier*1 , P. Michel2 and R. Gourdon1 1, Society of design and production engineering for wastewater purification, 5 Allée Alban Vistel, F-69110 Wetlands (VFCW) is well developed in France and other countries for the treatment of wastewaters from small

Boyer, Edmond


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)



Evaluation of waste activated sludge as a coagulant aid for the treatment of industrial wastewater containing mixed surfactants  

Microsoft Academic Search

Wastewater generated by the industry manufacturing detergents and various kinds of consumer products normally contains very high contents of mixed surfactants, organic matters expressed as chemical oxygen demand (COD), and phosphates that must be treated prior to discharge to the aquatic environment. In this study, jar-test experiments were conducted to evaluate the waste activated sludge (WAS) as a coagulation aid

Tongchai Sriwiriyarat; Siriprapha Jangkorn



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



Wastewater Treatment  

NSDL National Science Digital Library 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.



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


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




EPA Science Inventory

This 71 - page Technology Transfer Environmental Regulations and echnology publication describes the Federal requirements promulgated in 1979 for reducing pathogens n wastewater sludge and provides guidance in determining whether individual sludge treatment andated or particular ...


coagulation flocculation sedimentation wastewater treatment. ...... metals cumulation soil samples Bardejov increased order: Pb Zn Cu ...... BET FT-IR evaluate pore structural ...... amendment desert reclaimed soil wheat jews mallow plants.preparing sewage sludge  

EPA Pesticide Factsheets

Search instead for coagulation flocculation sedimentation wastewater treatment. ...... metals cumulation soil samples Bardejov increased order: Pb Zn Cu ...... BET FT-IR evaluate pore structural ...... amendment desert reclaimed soil wheat jews mallow plants.preparing sewage sludge ?


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


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



Sequential modeling of fecal coliform removals in a full-scale activated-sludge wastewater treatment plant using an evolutionary process model induction system  

Microsoft Academic Search

We propose an evolutionary process model induction system that is based on the grammar-based genetic programming to automatically discover multivariate dynamic inference models that are able to predict fecal coliform bacteria removals using common process variables instead of directly measuring fecal coliform bacteria concentration in a full-scale municipal activated-sludge wastewater treatment plant. A sequential modeling paradigm is also proposed to

Chang-Won Suh; Joong-Won Lee; Yoon-Seok Timothy Hong; Hang-Sik Shin



Upflow anaerobic sludge blanket reactors for treatment of wastewater from the brewery industry  

E-print Network

Anaerobic digestion can be utilized to convert industrial wastewater into clean water and energy. The goal of this project was to set up lab-scale anaerobic digesters to collect data that will be used to develop and validate ...

Scampini, Amanda C



Performance of a combined system of microbial fuel cell and membrane bioreactor: wastewater treatment, sludge reduction, energy recovery and membrane fouling.  


A novel combined system of sludge microbial fuel cell (S-MFC) stack and membrane bioreactor (MBR) was proposed in this study. The non-consumed sludge in the MBR sludge-fed S-MFC was recycled to the MBR. In the combined system, the COD and ammonia treatment efficiencies were more than 90% and the sludge reduction was 5.1% higher than that of the conventional MBR. It's worth noting that the energy recovery and fouling mitigation were observed in the combined system. In the single S-MFC, about 75 mg L(-1) COD could be translated to electricity during one cycle. The average voltage and maximum power production of the single S-MFC were 430 mV and 51 mWm(-2), respectively. Additionally, the combined system was able to mitigate membrane fouling by the sludge modification. Except for the content decrease (22%), S-MFC destroyed simple aromatic proteins and tryptophan protein-like substances in loosely bound extracellular polymeric substances (LB-EPS). These results indicated that effective wastewater treatment, sludge reduction, energy recovery and membrane fouling mitigation could be obtained in the combined system. PMID:23722047

Su, Xinying; Tian, Yu; Sun, Zhicai; Lu, Yaobin; Li, Zhipeng



Response of anaerobic granular sludge to a shock load of zinc oxide nanoparticles during biological wastewater treatment.  


The increasing use of zinc oxide nanoparticles (ZnO NPs) in consumer and industrial products highlights a need to understand their potential environmental impacts. In this study, the response of anaerobic granular sludge (AGS) to a shock load of ZnO NPs during anaerobic biological wastewater treatment was reported. It was observed that the extracellular polymeric substances (EPS) of AGS and the methane production were not significantly influenced at ZnO NPs of 10 and 50 mg per gram of total suspended solids (mg/g-TSS), but they were decreased when the dosage of ZnO NPs was greater than 100 mg/g-TSS. The visualization of EPS structure with multiple fluorescence labeling and confocal laser scanning microscope revealed that ZnO NPs mainly caused the decrease of proteins by 69.6%. The Fourier transform infrared spectroscopy analysis further indicated that the C-O-C group of polysaccharides and carboxyl group of proteins in EPS were also changed in the presence of ZnO NPs. The decline of EPS induced by ZnO NPs resulted in their deteriorating protective role on the inner microorganisms of AGS, which was in correspondence with the observed lower general physiological activity of AGS and the death of microorganisms. Further investigation showed that the negative influence of ZnO NPs on methane production was due to their severe inhibition on the methanization step. PMID:22587556

Mu, Hui; Zheng, Xiong; Chen, Yinguang; Chen, Hong; Liu, Kun



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



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...


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


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




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...


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


Psychrophilic (6-15 degreesC) anaerobic treatment of malting wastewater was investigated. A two-module expanded granular sludge bed reactor system with a total volume of 140 dm3 was used to treat malting wastewater having a soluble and total chemical oxygen demand (COD) between 233 and 1778 mg dm-3 and between 317 and 4422 mg dm-3, respectively. The removal efficiencies at 6 degreesC 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-3 day-1. The removal efficiencies at 10-15 degreesC 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-3 day-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, thus providing a very high effluent quality (soluble COD < 200 mg dm-3) of the total system. The stability of module I concerning suspended solids could be restored by presettling the wastewater. PMID:9841647

Rebac; van Lier JB; Lens; van Cappellen J; Vermeulen; Stams; Dekkers; Swinkels; Lettinga



OC-ALC hazardous waste minimization strategy: Reduction of industrial biological sludge from industrial wastewater treatment facilities  

SciTech Connect

Oklahoma City Air Logistics Center (OC-ALC) is one of five US Air Force Logistic Centers that perform depot level maintenance of aircraft. As part of the maintenance process, aircraft are cleaned, chemically depainted, repainted, and electroplated. These repair/maintenance processes generate large quantities of dilute liquid effluent which are collected and treated in the Industrial Waste Treatment Plant (IWTP) prior to hazardous waste disposal. OC-ALC is committed to reducing the use of hazardous materials in the repair and maintenance of aircraft and ancillary components. A major Air Force initiative is to reduce the amount of hazardous waste discharged off-site by 25% by the end of CY96 and 50% by CY99 end. During maintenance and repair operations, organic chemicals are employed. These organics are discharged to the IWTP for biological degradation. During the biological digestion process, a biological sludge is generated. OC-ALC engineers are evaluating the applicability of a biosludge acid/heat treatment process. In the acid hydrolysis process, an acid is added to the biosludge and processed through a hot, pressurized reactor where the majority of the biosolids are broken down and solubilized. The resulting aqueous product stream is then recycled back to the traditional biotreatment process for digestion of the solubilized organics. The solid waste stream is dewatered prior to disposal. The objective of the subsequent effort is to achieve a reduction in hazardous waste generation and disposal by focusing primarily on end-of-the-pipe treatment at the IWTP. Acid hydrolysis of biosludge is proving to be a practical process for use in industrial and municipal wastewater biotreatment systems that will lower environmental and economic costs by minimizing the production and disposal of biosludge.

Hall, F.E. Jr. [OC-ALC/EMV, Tinker AFB, OK (United States)



The effect of chemical composition on the PCT durability of mixed waste glasses from wastewater treatment sludges  

SciTech Connect

An experimental program has been designed to examine the chemical durability of glass compositions derived from the vitrification of simulated wastewater treatment sludges. These sludges represent the majority of low-level mixed wastes currently in need of treatment by the US DOE. The major oxides in these model glasses included SiO{sub 2}, Al{sub 2}O{sub 3}, B{sub 2}O{sub 3}, Na{sub 2}O, CaO and Fe{sub 2}O{sub 3}. In addition, three minor oxides, BaO, NiO, and PbO, were added as hazardous metals. The major oxides were each varied at two levels resulting in 32 experimental glasses. The chemical durability was measured by the 7-Day Product Consistency Test (PCT). The normalized sodium release rates (NRR{sub Na}) of these glasses ranged from 0.01 to 4.99 g/m{sup 2}. The molar ratio of the glass-former to glass-modifier (F/M) was found to have the greatest effect on PCT durability. Glass-formers included SiO{sub 2}, Al{sub 2}O{sub 3}, and B{sub 2}O{sub 3}, while Na{sub 2}O, CaO, BaO, NiO, and PbO were glass-modifiers. As this ratio increased from 0.75 to 2.0, NRR{sub Na} was found to decrease between one and two orders of magnitude. Another important effect on NRR{sub Na} was the Na{sub 2}O/CaO ratio. As this ratio increased from 0.5 to 2.0, NRR{sub Na} increased up to two orders of magnitude for the glasses with the low F/M ratio but almost no effect was observed for the glasses with the high F/M ratio. Increasing the iron oxide content from 2 to 18 mole% was found to decrease NRR{sub Na} one order of magnitude for the glasses with low F/M but iron had little effect on the glasses with the high F/M ratio. The durability also increased when 10 mole percent Al{sub 2}O{sub 3} was included in low iron oxide glasses but no effect was observed with the high iron glasses. The addition of B{sub 2}O{sub 3} had little effect on durability. The effects of other composition parameters on durability are discussed as well.

Resce, J.L.; Ragsdale, R.G.; Overcamp, T.J. [Clemson Univ., SC (United States); Bickford, D.F.; Cicero, C.A. [Savannah River Technology Center, Aiken, SC (United States)




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...


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


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



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


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



Health Effects of a Wastewater Treatment System.  

National Technical Information Service (NTIS)

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 Tecumse...

K. F. Fannin, K. W. Cochran, H. Ross, A. S. Monto



Current levels and composition profiles of emerging halogenated flame retardants and dehalogenated products in sewage sludge from municipal wastewater treatment plants in china.  


Occurrence of new toxic chemicals in sludge from wastewater treatment plants (WWTPs) is of concern for the environment and human health. Alternative halogenated flame retardants (HFRs) are a group of potentially harmful organic contaminants in the environment. In this study, a nationwide survey was carried out to identify the occurrence of HFRs and their potential dehalogenated products in sewage sludge from 62 WWTPs in China. Of all 20 target chemicals analyzed, decabromodiphenyl ethane (DBDPE), hexabromocyclododecane (HBCD) and 1, 2-bis (2,4,6-tribromophenoxy)-ethane (BTBPE) were detected in all sludge samples, and the concentrations were in the range of 0.82-215, 0.09-65.8, and 0.10-2.26 ng g(-1) d.w., respectively. Dechlorane Plus (DP) was found in 60 of 62 samples, and the concentration ranged from nd-298 ng g(-1) with a mean of 18.9 ng g(-1) d.w. The anti-DP fractional abundance fanti (0.79) in the samples was much higher than the commercial DP composition (fanti = 0.59), indicating a stereoselective degradation. Comparison with global sludge concentrations of HFRs indicate that China is at the medium pollution level in the world. Principal components analysis revealed that strong correlations existed between ln-transformed concentrations (natural logarithm) of the dominant BFRs and total organic carbon (TOC) as well as industrial wastewater proportion, influent volume and serving population. Significant linear relationships (R = 0.360-0.893, p < 0.01) were found among emerging brominated flame retardants (BFRs), suggesting their common commercial applications and release sources to the environment. Two kinds of dehalogenated products, pentabromocyclododecane (PBCD) and undecachloropentacyclooctadecadiene (Cl11-DP), derived from HBCD and DP, were also identified in sewage sludge for the first time. PMID:25286358

Zeng, Lixi; Yang, Ruiqiang; Zhang, Qinghua; Zhang, Haidong; Xiao, Ke; Zhang, Haiyan; Wang, Yawei; Lam, Paul K S; Jiang, Guibin



Environmental Evaluation of Different Treatment Processes for Sludge from Urban Wastewater Treatments: Anaerobic Digestion versus Thermal Processes (10 pp)  

Microsoft Academic Search

lost. Tar and char, co-products from pyrolysis, are good exam- ples that were evaluated here, recycling of bottom ashes from sludge incineration or manufacture of ceramic materials from sludge are other options to be studied in the near future. Conclusion. During the last few years, several opinions have been declared in favour of land application, incineration or py- rolysis, but

Almudena Hospido; Teresa Moreira; María Martín; Miquel Rigola; Gumersindo Feijoo



Wastewater Treatment  


... roads, parking lots, and rooftops can harm our rivers and lakes. Why Treat Wastewater? It's a matter ... fishing enthusiasts, and future generations. Wildlife Habitats Our rivers and ocean waters teem with life that depends ...


Performance analysis of power generating sludge combustion plant and comparison against other sludge treatment technologies  

Microsoft Academic Search

Expectations on wastewater sludge treatment and recovery of its energy and material contents are increasing because of the tightening legislation and the obligation to reduce environmental impacts of sludge disposal. The objective of this study was to analyze the performance of a heat and power generating sludge combustion plant from technical and economical viewpoints and to compare the studied concept

Mika Horttanainen; Juha Kaikko; Riikka Bergman; Minna Pasila-Lehtinen; Janne Nerg




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...


Relevance of the sludge retention time (SRT) as design criteria for wastewater treatment plants for the removal of endocrine disruptors and pharmaceuticals from wastewater  

Microsoft Academic Search

Wastewater treatment plants (WWTPs) represent a significant source for the input of micro pollutants as endocrine disruptors (EDs) or pharmaceutically active compounds (PhACs) into the aquatic environment. Treatment efficiency of WWTPs often is reported, taking into account only inflow and effluent concentrations without further specification of the WWTP investigated. In order to allow comparison and evaluation of the removal efficiency

N. Kreuzinger; M. Clara; B. Strenn; H. Kroiss



Seasonal and time variability of heavy metal content and of its chemical forms in sewage sludges from different wastewater treatment plants.  


Sewage sludges obtained from seven wastewater treatment plants from the province of Salamanca, Spain, were periodically sampled to determine seasonal and time variation of their elemental composition over 2000 to 2002. The aim of this paper was to provide additional insight to evaluate the potential environmental impact following soil incorporation of these materials as amendments. Aqua regia extractable metals (pseudo total content) of Cd, Cr, Cu, Ni, Pb and Zn were determined and furthermore, the main chemical forms of metals within the sludge were evaluated using a five-step fractionation procedure. All the studied sludges displayed high fertility properties due to their richness of OC, P and K. Total mean concentrations of Cd, Cr, Cu, Ni, Pb and Zn in the sludges were within the regulation of the Spanish legislation. Using an multifactor analysis of variance, significant differences between Cr, Cu, Ni, Pb and Zn pseudo total contents (p<0.01) of sludges at different sites were found while the Cd content was statistically similar. Also significant differences were found between these pseudo total contents of heavy metals in samples collected along the time after three years (0.001sludge up to 35% of total metal content. Cu and Pb distributed in the organically bound fraction up to 25% and 60%, respectively. The Cd, Cr, Cu, Ni, Zn in sludges were predominantly bound within the oxide or silicate components. Significant differences between distribution fractions of metals considered together (p<0.001) were found at different years, and for each individual metal, significant differences can be observed between distribution fractions of sludges collected at different sites, times and seasonal periods. The results showed that the studied sludges can potentially enhance soil agronomic properties. The fractionation data indicated that most metals occur in weakly mobile, non-bioavailable form, and only Cd, could have potential moderate mobility in soil-water system. PMID:17532025

García-Delgado, M; Rodríguez-Cruz, M S; Lorenzo, L F; Arienzo, M; Sánchez-Martín, M J



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


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




Microsoft Academic Search

As the requirements concerning effluent total nitrogen limits are getting more strict, it is necessary to look for methods of N-load reduction, right now in wastewater plants. The purification of sludge water seems to be promising, as these waters carry over 20% of biogenic compounds to the main treatment reactor. In this article the research results of return liquors treatment

Krystyna Konieczny


Performance of the biosorptive activated sludge (BAS) as pre-treatment to UF for decentralized wastewater reuse.  


A biosorptive activated sludge (BAS) was operated at lab-scale with diluted and concentrated municipal wastewater to study the efficiency of removal of organics (particulate and soluble COD) and recovery of nutrients (TKN, ammonia, phosphorus). The system performed significantly better with concentrated wastewater, where COD removal efficiency was 80% at organic loading rates between 10 and 20kg m(-3)d(-1). Supplementation of ferrous iron at 20mg L(-1), significantly improved both the removal of particulate, soluble COD and phosphorus. The effluent from the BAS was further treated using an ultrafiltration process with backwashing. The average permeate flux (at constant TMP=0.3bar) increased from 23 to 28 and 34L m(-2)h(-1) when raw sewage, BAS without iron, and iron respectively were tested. The proposed technology is compact, efficient and suitable for decentralized water reuse, while the capital and operational expenses were calculated as 0.64 and 0.43€ m(-3), respectively. PMID:24525216

Diamantis, V; Eftaxias, A; Bundervoet, B; Verstraete, W



The survival of Escherichia coli, faecal coliforms and enterobacteriaceae in general in soil treated with sludge from wastewater treatment plants.  


We monitored the effect of the application of treated sludge on the behaviour of enterobacteriaceae (mainly faecal coliforms and especially Escherichia coli) in the soil, and studied their evolution over time after application. Three different sludges were used: two from a municipal sewage plant, one of them had been subjected to anaerobic digestion and heat drying, and the other to anaerobic digestion and mechanical dehydration, and one from a dairy waste treatment to aerobic digestion and gravity thickening. Two types of tests were carried out: type O, in the open air, with no possibility of controlling humidity or temperature; and type L, under laboratory conditions, with controlled temperature and humidity. Sludge tests were also run on unscreened soil previously treated with chemical fertilizer. After 80 days of experimentation the populations of faecal coliforms and E. coli had decreased considerably or were undetectable in assays carried out on the soil/sludge mixtures, under both open-air and laboratory conditions, but that, over the same period, in the mixtures containing chemical fertilizer (calcium ammonium nitrate) there had been a considerable increase in the micro-organism populations studied. PMID:15051081

Estrada, I B; Aller, A; Aller, F; Gómez, X; Morán, A



Ozone treatment of textile wastewaters for reuse  

Microsoft Academic Search

Treatment of textile wastewaters by means of an ozonation pilot plant are described. Wastewaters used were produced by a dyeing and finishing factory and were first treated in an active sludge plant and filtrated through sand. In the appropriate conditions very high colour removal (95-99%) was achieved and the effluent could be reused in production processes requiring water of high

G. Ciardelli; G. Capannelli; A. Bottino


Pretreatment of petrochemical wastewater by coagulation and flocculation and the sludge characteristics  

Microsoft Academic Search

In the present study, coagulation–flocculation was investigated as a pretreatment process for the treatment of purified terephthalic acid (PTA) wastewater. The effect of various inorganic and organic coagulants on the treatment of wastewater collected from flow equalization tank of an effluent treatment plant was studied. The settling and filtration characteristics of the sludge were also studied. The jar tests revealed

Shilpi Verma; Basheshwar Prasad; Indra Mani Mishra



The Microbial Database for Danish wastewater treatment plants with nutrient removal (MiDas-DK) - a tool for understanding activated sludge population dynamics and community stability.  


Since 2006 more than 50 Danish full-scale wastewater treatment plants with nutrient removal have been investigated in a project called 'The Microbial Database for Danish Activated Sludge Wastewater Treatment Plants with Nutrient Removal (MiDas-DK)'. Comprehensive sets of samples have been collected, analyzed and associated with extensive operational data from the plants. The community composition was analyzed by quantitative fluorescence in situ hybridization (FISH) supported by 16S rRNA amplicon sequencing and deep metagenomics. MiDas-DK has been a powerful tool to study the complex activated sludge ecosystems, and, besides many scientific articles on fundamental issues on mixed communities encompassing nitrifiers, denitrifiers, bacteria involved in P-removal, hydrolysis, fermentation, and foaming, the project has provided results that can be used to optimize the operation of full-scale plants and carry out trouble-shooting. A core microbial community has been defined comprising the majority of microorganisms present in the plants. Time series have been established, providing an overview of temporal variations in the different plants. Interestingly, although most microorganisms were present in all plants, there seemed to be plant-specific factors that controlled the population composition thereby keeping it unique in each plant over time. Statistical analyses of FISH and operational data revealed some correlations, but less than expected. MiDas-DK ( will continue over the next years and we hope the approach can inspire others to make similar projects in other parts of the world to get a more comprehensive understanding of microbial communities in wastewater engineering. PMID:23752384

Mielczarek, A T; Saunders, A M; Larsen, P; Albertsen, M; Stevenson, M; Nielsen, J L; Nielsen, P H



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



Aerobic versus anaerobic wastewater treatment  

SciTech Connect

Biological wastewater treatment facilities are designed to emulate the purification process that occurs naturally in rivers, lakes and streams. In the simulated environment, conditions are carefully manipulated to spur the degradation of organic contaminants and stabilize the residual sludge. Whether the treatment process is aerobic or anaerobic is determined by a number of factors, including the composition of the wastewater, the degree of stabilization required for environmental compliance and economic viability. Because anaerobic digestion is accomplished without oxygen in a closed system, it is economical for pretreatment of high-strength organic sludge. Before the effluent can be discharged, however, followup treatment using an aerobic process is required. Though it has the drawback of being energy intensive, aerobic processing, the aeration of organic sludges in an open tank, is the primary method for treatment of industrial and municipal wastewater. Aerobic processes are more stable than anaerobic approaches and can be done rather simply, particularly with trickling filters. Gradually, the commercialization of modular systems that are capable of aerobic and anaerobic digestion will blur the distinctions between the two processes. Systems that boast those capabilities are available now.

Robinson, D.G.; White, J.E.; Callier, A.J. [Burns and McDonnell Engineering Co., Kansas City, MO (United States)



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



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




E-print Network

ADAPTIVE MODEL BASED CONTROL FOR WASTEWATER TREATMENT PLANTS Arie de Niet1 , Maartje van de Abstract In biological wastewater treatment, nitrogen and phosphorous are removed by activated sludge considerably to the increase of energy-efficiency in wastewater treatment. To this end, we introduce

Boucherie, Richard J.


Wastewater treatment using ferrous sulfate  

SciTech Connect

Treatment of industrial wastewater with coagulants is used extensively in the thorough removal of emulsified tars and oils. The central plant laboratory at the Zhdanov Coke Works conducted investigations of the treatment of wastewater, subsequently used for quenching coke, with ferrous sulfate. Laboratory tests and subsequent industrial tests demonstrated the efficiency of the method. In order to further intensify the wastewater treatment process we conducted laboratory tests with the addition of certain quantities of other coagulation reagents, for example polyacrylamide (PAA) and caustic soda, in addition to the ferrous sulfate. The combined use of polyacrylamide and ferrous sulfate permits instant coagulation of the sludge and very rapid (5 to 10 min) clarification of the water. In addition, in this case the degree of purification of the water is less dependent on the initial concentration of impurities. The purification is also improved when caustic soda is added, raising the pH. From the data it is apparent that an identical degree of purification of the water may be achieved either by increasing the consumption of ferrous sulfate, or by adding PAA or NaOH. During industrial tests of the purification of wastewater with ferrous sulfate, we also investigated the resulting sludge. The use of ferrous sulfate causes a significant increase in its quantity (by a factor of 1.5 to 1.8) and in its oil content (by a factor of 2 to 2.5). The water content in the sludge decreases. The sludge (in the quantity of 0.6% of the charge) may be added to the coking charge.

Boetskaya, K.P.; Ioffe, E.M.



Anaerobic digestion of pulp and paper mill wastewater and sludge.  


Pulp and paper mills generate large amounts of waste organic matter that may be converted to renewable energy in form of methane. The anaerobic treatment of mill wastewater is widely accepted however, usually only applied to few selected streams. Chemical oxygen demand (COD) removal rates in full-scale reactors range between 30 and 90%, and methane yields are 0.30-0.40 m(3) kg(-1) COD removed. Highest COD removal rates are achieved with condensate streams from chemical pulping (75-90%) and paper mill effluents (60-80%). Numerous laboratory and pilot-scale studies have shown that, contrary to common perception, most other mill effluents are also to some extent anaerobically treatable. Even for difficult-to-digest streams such as bleaching effluents COD removal rates range between 15 and 90%, depending on the extent of dilution prior to anaerobic treatment, and the applied experimental setting. Co-digestion of different streams containing diverse substrate can level out and diminish toxicity, and may lead to a more robust microbial community. Furthermore, the microbial population has the ability to become acclimated and adapted to adverse conditions. Stress situations such as toxic shock loads or temporary organic overloading may be tolerated by an adapted community, whereas they could lead to process disturbance with an un-adapted community. Therefore, anaerobic treatment of wastewater containing elevated levels of inhibitors or toxicants should be initiated by an acclimation/adaptation period that can last between a few weeks and several months. In order to gain more insight into the underlying processes of microbial acclimation/adaptation and co-digestion, future research should focus on the relationship between wastewater composition, reactor operation and microbial community dynamics. The potential for engineering and managing the microbial resource is still largely untapped. Unlike in wastewater treatment, anaerobic digestion of mill biosludge (waste activated sludge) and primary sludge is still in its infancy. Current research is mainly focused on developing efficient pretreatment methods that enable fast hydrolysis of complex organic matter, shorter sludge residence times and as a consequence, smaller sludge digesters. Previous experimental studies indicate that the anaerobic digestibility of non-pretreated biosludge from pulp and paper mills varies widely, with volatile solids (VS) removal rates of 21-55% and specific methane yields ranging between 40 and 200 mL g(-1) VS fed. Pretreatment can increase the digestibility to some extent, however in almost all reported cases, the specific methane yield of pretreated biosludge did not exceed 200 mL g(-1) VS fed. Increases in specific methane yield mostly range between 0 and 90% compared to non-pretreated biosludge, whereas larger improvements were usually achieved with more difficult-to-digest biosludge. Thermal treatment and microwave treatment are two of the more effective methods. The heat required for the elevated temperatures applied in both methods may be provided from surplus heat that is often available at pulp and paper mills. Given the large variability in specific methane yield of non-pretreated biosludge, future research should focus on the links between anaerobic digestibility and sludge properties. Research should also involve mill-derived primary sludge. Although biosludge has been the main target in previous studies, primary sludge often constitutes the bulk of mill-generated sludge, and co-digestion of a mixture between both types of sludge may become practical. The few laboratory studies that have included mill primary sludge indicate that, similar to biosludge, the digestibility can range widely. Long-term studies should be conducted to explore the potential of microbial adaptation to lignocellulosic material which can constitute more than half of the organic matter in pulp and paper mill sludge. PMID:25150519

Meyer, Torsten; Edwards, Elizabeth A




EPA Science Inventory

Fecal matter potentially containing pathogenic microorganisms and chemical contaminants enters community wastewater collection systems from hospitals, funeral homes, animal slaughtering operations, and dwellings. While these wastewaters are cleansed in the wastewater treatment p...


MBR- a promising technology for wastewater treatment: An overview  

Microsoft Academic Search

The principle of degradation of organic hazardous matters in wastewater by microorganism has been discussed. It is shown how the mechanism of biodegradation is successfully used in conventional activated sludge processes for wastewater treatment, and also in advanced technologies as Membrane Bioreactor (MBR). The MBR systems are compared with conventional wastewater treatment systems, and the advantages of the first over

M A Islam; M S I Mozumder; M T Uddin


Magnetic Separation of Ferrite Sludge from a Wastewater Purification Process  

Microsoft Academic Search

The purification of wastewater containing dissolved metal ions by in situ precipitation gives rise to a sludge composed mainly of ferrites MeXFe3-xO4 (where Me represents the existing metal ions in the wastewater). Oxides, iron oxy-hydroxides and other impurities are also present in the sludge in smaller proportion. The present investigation proposes magnetic separation of the sludge to recover the ferrites

E. Barrado; F. Prieto; J. Ribas; F. A. López



Challenge of psychrophilic anaerobic wastewater treatment  

Microsoft Academic Search

Psychrophilic anaerobic treatment is an attractive option for wastewaters that are discharged at moderate to low temperature. The expanded granular sludge bed (EGSB) reactor has been shown to be a feasible system for anaerobic treatment of mainly soluble and pre-acidified wastewater at temperatures of 5–10°C. An organic loading rate (OLR) of 10–12 kg chemical oxygen demand (COD) per cubic meter

Gatze Lettinga; Salih Rebac; Grietje Zeeman



Lime stabilized sludge treatment of acid soils relative to soil acidity minimums for sludge application  

Microsoft Academic Search

Lime stabilized sludge (LSS) from wastewater treatment plants contains lime, which may neutralize soil acidity, and P, an essential plant nutrient. Guidelines for use of land application of secondary sludges call for the soil pH to be at 6.5 or above prior to application. This greenhouse study was initiated to determine the effects of placement of LSS from two sources

J. R. Brown; Lyndon Brush




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 ...


The survival of Escherichia coli, faecal coliforms and enterobacteriaceae in general in soil treated with sludge from wastewater treatment plants  

Microsoft Academic Search

We monitored the effect of the application of treated sludge on the behaviour of enterobacteriaceae (mainly faecal coliforms and especially Escherichia coli) in the soil, and studied their evolution over time after application. Three different sludges were used: two from a municipal sewage plant, one of them had been subjected to anaerobic digestion and heat drying, and the other to

I. B. Estrada; A. Aller; F. Aller; X. Gómez; A. Morán



Factors affecting the removal of metals during activated sludge wastewater treatment I. The role of soluble ligands  

Microsoft Academic Search

Samples of mixed liquor were withdrawn from a laboratory-scale activated sludge simulation operated at a range of sludge ages from 3 to 12 days in order to examine the difference in metal uptake by the mixed liquor biomass in the absence and presence of soluble ligands. One half of the samples were centrifuged, washed, and resuspended in physiological saline solution,

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



Wastewater Treatment Systems  

NSDL National Science Digital Library

Every time you take a bath, wash your clothes, flush the toilet, or run water down the kitchen or bathroom sinks you are creating wastewater. The average household generates between 60-75 gallons of wastewater each day. So where does that wastewater go? By working through this instructional unit, you will be able to better answer this question. Please read through the information provided below to learn more about wastewater and how it is treated. After you have completed the unit, you will need to complete the Wastewater Treatment worksheet that will be handed out to you in class by Professor Taylor. If you live in a small rural community you are most likely to have a septic tank system to treat your wastewater. This type of system treats your wastewater on your own property near your home. To learn more about septic tank sytems see the following link provided. Sewer and Septic Tanks If ...

Taylor, Professor D.



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


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



Wastewater treatment plant cogeneration options  

SciTech Connect

This paper reviews municipal sewage cogeneration and digester gas utilization options available to wastewater treatment plants, and will focus on utilizing the digester gas in combustion turbines and engine-generator systems. Defining the digestion and gas generation process is crucial to understanding the best gas utilization system. In municipal wastewater treatment plants biosolids (sludge) reduction is accomplished using aerobic or anaerobic digestion. The basic process of treating sewage solids with digestion is not new and has been practiced as far back as the nineteenth century. High energy usage consumed by aerobic blow systems supplying air to the process and the potential ``free`` energy generated by anaerobic digesters sometimes sways designers to select anaerobic over aerobic digestion. The following areas will be covered in this paper: gas utilization and cogeneration; definition of digestion process; sizing the cogeneration system and reviewing the systems components; emissions requirements and options; and capital, and O and M cost analysis.

Stringfield, J.G. [Black and Veatch, Kansas City, MO (United States)




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...



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...



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...


Membrane fouling in an anaerobic dynamic membrane bioreactor (AnDMBR) for municipal wastewater treatment: Characteristics of membrane foulants and bulk sludge  

Microsoft Academic Search

An anaerobic dynamic membrane bioreactor (AnDMBR) treating municipal wastewater with a high flux of 65L\\/(m2h) was operated for 11 months. Organic and inorganic membrane foulants and bulk sludge characteristics were investigated using particle size distribution analyzer, three-dimensional excitation–emission matrix fluorescence spectroscopy and X-ray fluorescence analysis. The fouling layers exhibited a double-layered structure, i.e., a loosely bound outer layer and a

Xinying Zhang; Zhiwei Wang; Zhichao Wu; Tianye Wei; Fenghai Lu; Jun Tong; Suihai Mai



Pollutant monitoring in sludge treatment wetlands.  


Phragmites australis for sludge dewatering and stabilization processes have been widely proved. The presence of reeds, indeed, efficiently allows solids dewatering and organic matter stabilization in order to obtain a stabilised product that can be suitable for land application, even if its environmental impact has to be considered. The actual revision of the European Union's Working Document on Sludge (2000), in fact, seems to be addressed to detect two principal categories of pollutants in sludge for agricultural use: heavy metals and toxic organic compounds. In this study are presented results about sludge stabilization and monitoring of heavy metal fractionation and organic compounds in four urban wastewater treatment plants managed by Acque S.p.A., (Tuscany, Italy). To evaluate the process of sludge stabilization parameters were determined that highlight the biochemical and chemico-structural properties of sludge organic matter. The results showed that stabilization of the sludge over time occurred as shown by the low content of water soluble carbon and dehydrogenase activity, and by the re-synthesis of humic-like matter highlighted by the pyrolytic indices of mineralization and humification. Results about fractionation showed that heavy metals were retained in fractions related to the stabilized organic matter. Moreover, toxic organic compounds showed a drastic reduction at the end of the monitoring period. PMID:22179656

Peruzzi, E; Masciandaro, G; Macci, C; Doni, S; Ceccanti, B



Including the effects of filamentous bulking sludge during the simulation of wastewater treatment plants using a risk assessment model.  


The main objective of this paper is to demonstrate how including the occurrence of filamentous bulking sludge in a secondary clarifier model will affect the predicted process performance during the simulation of WWTPs. The IWA Benchmark Simulation Model No. 2 (BSM2) is hereby used as a simulation case study. Practically, the proposed approach includes a risk assessment model based on a knowledge-based decision tree to detect favourable conditions for the development of filamentous bulking sludge. Once such conditions are detected, the settling characteristics of the secondary clarifier model are automatically changed during the simulation by modifying the settling model parameters to mimic the effect of growth of filamentous bacteria. The simulation results demonstrate that including effects of filamentous bulking in the secondary clarifier model results in a more realistic plant performance. Particularly, during the periods when the conditions for the development of filamentous bulking sludge are favourable--leading to poor activated sludge compaction, low return and waste TSS concentrations and difficulties in maintaining the biomass in the aeration basins--a subsequent reduction in overall pollution removal efficiency is observed. Also, a scenario analysis is conducted to examine i) the influence of sludge retention time (SRT), the external recirculation flow rate (Q(r)) and the air flow rate in the bioreactor (modelled as k(L)a) as factors promoting bulking sludge, and ii) the effect on the model predictions when the settling properties are changed due to a possible proliferation of filamentous microorganisms. Finally, the potentially adverse effects of certain operational procedures are highlighted, since such effects are normally not considered by state-of-the-art models that do not include microbiology-related solids separation problems. PMID:19695661

Flores-Alsina, Xavier; Comas, Joaquim; Rodriguez-Roda, Ignasi; Gernaey, Krist V; Rosen, Christian



Start-up of a granular sludge sequencing batch reactor for the treatment of 2,4-dichlorophenol-contaminated wastewater.  


In this study, a granular sludge sequencing batch reactor (GSBR) was started-up for the biological aerobic treatment of wastewater containing highly toxic 2,4-dichlorophenol (2,4-DCP), in presence of readily biodegradable sodium acetate (NaAc) as the growth substrate. Different influent concentrations of NaAc (420-800 mg/L) and 2,4-DCP (0-20 mg/L), as well as different operating conditions (i.e. cycle length), were tested in order to determine the optimal strategy for successful GSBR start-up: stable granulation and complete 2,4-DCP removal were achieved only when high NaAc influent concentration and volumetric organic loading rates (800 mg/L and 1.9 kgCOD/(m(3)·d), respectively), prolonged reaction phase (cycle time of 4 hours) and gradual increase of 2,4-DCP concentration in the influent were applied, thus providing useful information for process optimization in view of future scale-up. Granules were initially colonized by fungi which progressively disappeared during the start-up process, and complete 2,4-DCP removal was mostly due to bacterial activity, in particular Betaproteobacteria, as shown by fluorescence in situ hybridization (FISH). PMID:24292461

Milia, S; Porcu, R; Rossetti, S; Carucci, A



Treatment of phenol and cresols in upflow anaerobic sludge blanket (UASB) process: a review  

Microsoft Academic Search

Upflow anaerobic sludge blanket (UASB) process has been successfully applied in the treatment of municipal and industrial wastewaters. Several researchers have investigated the suitability of the process for the treatment of phenols and phenolic wastewaters. The anaerobic treatment of phenols is still at an investigative stage. With increasing recognition of the UASB process, feasibility studies on the treatment of wastewater

Gali S. Veeresh; Pradeep Kumar; Indu Mehrotra



Including the effects of filamentous bulking sludge during the simulation of wastewater treatment plants using a risk assessment model  

Microsoft Academic Search

The main objective of this paper is to demonstrate how including the occurrence of filamentous bulking sludge in a secondary clarifier model will affect the predicted process performance during the simulation of WWTPs. The IWA Benchmark Simulation Model No. 2 (BSM2) is hereby used as a simulation case study. Practically, the proposed approach includes a risk assessment model based on

Xavier Flores-Alsina; Joaquim Comas; Ignasi Rodriguez-Roda; Krist V. Gernaey; Christian Rosen




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...


State of the art of biogranulation technology for wastewater treatment  

Microsoft Academic Search

Biogranulation technology developed for wastewater treatment includes anaerobic and aerobic granulation processes. Anaerobic granulation is relatively well known, but research on aerobic granulation commenced only recently. Many full-scale anaerobic granular sludge units have been operated worldwide, but no report exists of similar units for aerobic granulation. This paper reviews the fundamentals and applications of biogranulation technology in wastewater treatment. Aspects

Yu Liu; Joo-Hwa Tay



Genotoxicity testing of wastewater sludge using the Allium cepa anaphase-telophase chromosome aberration assay.  


Wastewater sludges were analysed in the Allium cepa genotoxicity test. They were sampled during three winter periods from three Danish municipal wastewater treatment plants differing in size and industrial load. The toxicity of the sludge was tested in the Allium root inhibition assay, and the results expressed as EC30 and EC50 values showed that the toxicity could be positive correlated to the industrial load. However, when genotoxicity was tested at concentrations corresponding to the EC30 and EC50 values in the A. cepa anaphase-telophase assay, only two sludge samples from the smallest plant with the lowest industrial load induced significant chromosome aberrations. Concentrations of the heavy metal's Pb, Ni, Cr, Zn, Cu, and Cd were also determined and could partly be correlated with the toxicity of the sludge and the industrial load of the treatment plants. PMID:9757013

Rank, J; Nielsen, M H



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



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


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



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.



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.




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 ...


Harvesting Energy from Wastewater Treatment  

E-print Network

Harvesting Energy from Wastewater Treatment Bruce Logan Penn State University #12;Energy Costs? 5-7% of electricity used in USA is for water &wastewater #12;Global Energy & Health Issues 1 Billion people lack #12;Energy content of Wastewaters · Electricity "lost" to water and wastewater treatment= 0.6 quad


Antimicrobial resistance of fecal indicators in municipal wastewater treatment plant  

Microsoft Academic Search

Antimicrobial resistance of fecal coliforms (n = 153) and enterococci (n = 199) isolates was investigated in municipal wastewater treatment plant (WWTP) based on activated sludge system. The number of fecal indicators (in influent and effluent as well as in the aeration chamber and in return activated sludge mixture) was determined using selective media. Susceptibility of selected strains was tested against 19 (aminoglycosides, aztreonam,

A. ?uczkiewicz; K. Jankowska; S. Fudala-Ksi??ek; K. Ola?czuk-Neyman



On-Site Wastewater Treatment Systems: Trickling Filter  

E-print Network

Soil absorption field Septic tank Clarifier/Dosing tank Trickling filter On-site wastewater treatment systems Trickling filter Bruce Lesikar and Russell Persyn Extension Agricultural Engineering Specialist, Extension Assistant-Water Conservation... municipal wastewater before cities began using activated sludge aeration systems. Now, homes and businesses use trickling filters in on-site wastewater treatment systems. Each trickling filter system has several components: 3 A septic tank, which removes...

Lesikar, Bruce J.



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



E-print Network

93/0096 WASTEWATER TREATMENT OVER SAND COLUMNS TREATMENT YIELDS, LOCALISATION OF THE BIOMASS Domestic wastewater treatment by infiltration-percolation is a process that becomming common in France, a greater depth for desinfection purposes. KEYWORDS Wastewater treatment, Infiltration-percolation. Sand

Paris-Sud XI, Université de


Harvesting Energy from Wastewater Treatment  

E-print Network

Harvesting Energy from Wastewater Treatment Bruce Logan Penn State University #12;Energy Costs? 5-7% of electricity used in USA is for water &wastewater #12;Global Energy & Health IssuesGlobal Energy & Health content of WastewatersEnergy content of Wastewaters ·· ElectricityElectricity ""lostlost"" to water


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.



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


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 3 mg L(-1) to 7 mg L(-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 5 mg L(-1) nC60, compared to 35% for the control. Meanwhile, the cumulative loading amount of nitrite was reduced from 33 ?g mL(-1) to 25 ?g mL(-1) by the addition of 5 mg L(-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



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.



Treatment of wastewater containing phosphorus compounds  

SciTech Connect

Wastewater containing phosphorus values and BOD is initially admixed with recycled sludge containing activated biomass under anaerobic conditions, then contacted with oxygen-containing gas, followed by separation of a dense sludge layer from the mixed liquor. A portion of the sludge layer, containing the activated biomass, is held under non-aeration conditions for sufficient time to reduce any nitrates and/or nitrites contained therein, before admixture of the recycled sludge with the wastewater influent.

Block, Ch. S.; Hong, S.-H.



Effects of wastewater sludge and woodchip combinations on soil properties and growth of planted hardwood trees and willows on a restored site  

Microsoft Academic Search

Sludge from wastewater treatment plants and woodchips produced from urban tree pruning residues were used to improve soil conditions of a degraded site restored by planting trees and shrubs. The release of soil nitrogen resources was set by the proportions of sludge and woodchips applied. Combining 187 kg N\\/ha of sludge in one application with 200 m3\\/ha of woodchips instead

Alain Cogliastro; Gérald Domon; Stéphane Daigle



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


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



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


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 and showed the typical problems encountered with conventional sludge seeding and had continuously to be re-seeded. A PCR-based technique was developed for the rapid detection of E. sakazakii in the granular sludge. PMID:14719823

Keyser, M; Witthuhn, R C; Ronquest, L C; Britz, T J




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 ...


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


A simple model for secondary clarifier: application to wastewater treatment plant  

Microsoft Academic Search

Wastewater treatment by low-rate activated sludge in aerobic stabilization ponds is a treatment process that has been, for most Algerian towns, the preferred tool for treating their wastewater because it has proven most reliable and easier to operate. The wastewater treatment plant of the City of Setif (Algeria) is a good example for this type of process. It has a

Zahir Bakiri; Saci Nacef



Emergy evaluations for constructed wetland and conventional wastewater treatments  

NASA Astrophysics Data System (ADS)

Based on emergy synthesis, this study presents a comparative study on constructed wetland (CW) and conventional wastewater treatments with three representative cases in Beijing. Accounting the environmental and economic inputs and treated wastewater output based on emergy, different characteristics of two kinds of wastewater treatments are revealed. The results show that CWs are environment-benign, less energy-intensive despite the relatively low ecological waste removal efficiency (EWRE), and less cost in construction, operation and maintenance compared with the conventional wastewater treatment plants. In addition, manifested by the emergy analysis, the cyclic activated sludge system (CASS) has the merit of higher ecological waste elimination efficiency.

Zhou, J. B.; Jiang, M. M.; Chen, B.; Chen, G. Q.



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

Microsoft Academic Search

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 (17?-estradiol, estrone, estriol) in 24-h composite samples of influents and secondary effluents collected seasonally from five municipal sewage treatment plants in

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




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...


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




EPA Science Inventory

Emissions of metals and organics from a series of four wastewater sludge incinerators were determined. hree multiple hearth units and one fluidized bed combustor were tested. missions were controlled with a combination of venturi and/or tray impingement scrubbers. ne site incorpo...



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...


Upgrading of existing sludge treatment processes for phosphorus management serving a EBPR WWTP.  


For a large-scale wastewater treatment plant to comply with phosphorus consents using enhanced biological phosphorus removal processes, its sludge and liquor treatment processes need to be carefully upgraded. In this case study, the wastewater treatment plant of interest has three different types of sludge treated by two different and independent sludge treatment processes. The task of upgrading the sludge treatment systems to serve an EBPR process while satisfying other regulatory and operational constraints in a cost effective way presents an interesting challenge. A range of process options was investigated to include P-rich surplus activated sludge treatment, raw sludge treatment, and sludge liquors treatment. Sludge pre-liming, i.e. to introduce lime slurry into raw liquid sludge before the dewatering stage, was studied in bench-scale and full-scale trials for phosphorus precipitation and pathogen reduction. It was applied to the mixture of surplus activated sludge and imported sludge. The results showed that a complete phosphorus precipitation was achieved at above pH 9 with lime addition of 7% (w/w as calcium hydroxide to sludge dry weight). A satisfactory 2-log pathogen reduction was consistently achieved at above pH 11 with lime addition of 14% (w/w). The process significantly simplified the potential upgrading work for sludge and liquor treatment, compared to other alternatives. PMID:15242228

Chen, W; Steen, F M; Green, P G



Production of polyhydroxyalkanoates (PHA) by activated sludge treating municipal wastewater: effect of pH, sludge retention time (SRT), and acetate concentration in influent  

Microsoft Academic Search

In this paper, the production of biodegradable plastics polyhydroxyalkanoates (PHA) by activated sludge treating municipal wastewater was investigated. The effect of three operational factors, i.e. the acetate concentration in influent, pH, and sludge retention time (SRT) were studied. Sludge acclimatized with municipal wastewater supplemented with acetate could accumulate PHA up to 30% of sludge dry weight, while sludge acclimatized with

Adeline S. M Chua; Hiroo Takabatake; Hiroyasu Satoh; Takashi Mino



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.


Wastewater treatment of pulp and paper industry: a review.  


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



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



Fluorochemical Mass Flows in a Municipal Wastewater Treatment Facility  

PubMed Central

Fluorochemicals have widespread applications and are released into municipal wastewater treatment plants via domestic wastewater. A field study was conducted at a full-scale municipal wastewater treatment plant to determine the mass flows of selected fluorochemicals. Flow-proportional, 24-h samples of raw influent, primary effluent, trickling filter effluent, secondary effluent, and final effluent and grab samples of primary, thickened, activated, and anaerobically-digested sludge were collected over ten days and analyzed by liquid chromatography electrospray-ionization tandem mass spectrometry. Significant decreases in the mass flows of perfluorohexane sulfonate and perfluorodecanoate occurred during trickling filtration and primary clarification, while activated sludge treatment decreased the mass flow of perfluorohexanoate. Mass flows of the 6:2 fluorotelomer sulfonate and perfluorooctanoate were unchanged as a result of wastewater treatment, which indicates that conventional wastewater treatment is not effective for removal of these compounds. A net increase in the mass flows for perfluorooctane and perfluorodecane sulfonates occurred from trickling filtration and activated sludge treatment. Mass flows for perfluoroalkylsulfonamides and perfluorononanoate also increased during activated sludge treatment and are attributed to degradation of precursor molecules. PMID:17180988

Schultz, Melissa M.; Higgins, Christopher P.; Huset, Carin A.; Luthy, Richard G.; Barofsky, Douglas F.; Field, Jennifer A.



Immobilized cell augmented activated sludge process for enhanced nitrogen removal from wastewater.  


The immobilized cell augmented activated sludge (ICAAS) system combines a cell immobilization technique and an offline enricher-reactor for the bioaugmentation of the activated sludge system to improve treatment performances. In this study, enhanced nitrogen removal using ICAAS was investigated. Laboratory-scale, offline, batch enricher-reactors were used to maintain nitrification and denitrification activities of coimmobilized nitrifiers and denitrifiers used to augment a laboratory-scale completely mixed activated sludge system (CMAS) treating synthetic wastewater. Cellulose triacetate was the media used to entrap nitrifiers and denitrifiers at a 2:1 mass ratio. The ICAAS augmented with the coimmobilized cells between 5 and 20% by volume gained 24 +/- 5% higher nitrogen removal than a control CMAS, which provided nitrogen removal of 28 +/- 7%. The ICAAS scheme is a viable alternative for upgrading existing activated sludge systems to gain better nitrogen removal. . PMID:17966700

Jittawattanarat, Rungrod; Kostarelos, Konstantinos; Khan, Eakalak



Wastewater treatment with the internal MEMBIOR.  


At SEGHERSbetter technology for Water n.v., an internal aerobic membrane bioreactor was developed with submerged flat membrane plates: the internal MEMBIOR. This system has several advantages compared to a conventional wastewater such as: compactness, reduced sludge production and very high effluent quality. Both laboratory and pilot scale installations are available for respectively feasibility and on-site pilot tests. The data obtained from these pilot tests allow an optimal design and dimensioning of the MEMBIOR technology, resulting in proper investments cost with guarantees and performance. Research on the internal MEMBIOR technology is based upon biological and membrane performance, aeration linked aspects and sludge morphology. A brewery bio-effluent was obtained using an internal MEMBIOR superior to a conventional wastewater treatment plant, absolutely free of suspended solids. A significant shift in sludge morphology over time was observed. Lower oxygen transfer coefficients were found when the sludge concentration increased, giving rise to the need for an additional aeration. Membrane performance was enhanced using an additional module aeration system. PMID:15954574

Cornelissen, E R; Janse, W; Koning, J




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 (...



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



A direct comparison amongst different technologies (aerobic granular sludge, SBR and MBR) for the treatment of wastewater contaminated by 4-chlorophenol.  


Environmental concern on chlorinated phenols is rising due to their extreme toxicity even at low concentrations and their persistency in water and soils. Since the high amount of published data often lacks in terms of uniformity, direct comparisons amongst different treatment technologies are very difficult, or even impossible. In this study, granular sludge developed in an acetate-fed Granular sludge Sequencing Batch Reactor (GSBR) was used for the aerobic degradation of low chlorinated 4-chlorophenol (4CP), with readily biodegradable sodium acetate (NaAc) as growth substrate. A conventional Sequencing Batch Reactor (SBR) and a Membrane BioReactor (MBR) were operated in parallel under the same 4CP influent concentrations and/or 4CP volumetric organic loading rates as the GSBR, in order to carry out a direct comparison in terms of 4CP removal efficiencies and specific removal rates, effluent quality, waste sludge production, system simplicity, land area requirement, start-up times, NaAc dosage as growth substrate and maximum applied 4CP volumetric organic loading rate. A decision matrix was built to define the best technology to suit different scenarios: the GSBR was proved to be the most suitable technology when system simplicity, low land area requirement and short start-up times were considered as critical parameters for decision making. PMID:20116174

Carucci, Alessandra; Milia, Stefano; Cappai, Giovanna; Muntoni, Aldo



Constructed Wetlands and Waste Stabilization Ponds for municipal wastewater treatment in France: comparison of  

E-print Network

13 Constructed Wetlands and Waste Stabilization Ponds for municipal wastewater treatment in France In France, vertical flow constructed wetlands and waste stabilisation ponds are both extensive treatment Vertical Flow Constructed Wetlands, Waste Stabilization Ponds, operation and maintenance, sludge management

Paris-Sud XI, Université de



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...


Demonstration of solids-associated virus in wastewater and sludge.  

PubMed Central

Data presented demonstrate the relatively high multiplicity of solids-associated virus in field samples, i.e., wastewater, sludge, and soils. Influent, effluent, and chlorinated effluent samples showed 16.1 to 100% of the total virus demonstrated in samples to be solids associated. Three techniques for freeing solids-associated virus are described and compared. Using sonication of solids and polyethylene glycol concentration, virus was demonstrated in fully digested sludge (60 days at 34 C), sand at the site of a sewer leak, and dried sludge cake and mud 900 m downstream from a sewage disposal site. These data emphasize the inadequacy of virus concentration techniques that do not include the processing of solids. In situ elution failed to free solids-associated virus. PMID:180882

Wellings, F M; Lewis, A L; Mountain, C W



Effect of nitrogen and phosphate on the activated sludge efficiency in domestic wastewater purification  

Microsoft Academic Search

The activated sludge plants are the most newly effective treatment for domestic wastewater. These living systems required many factors to decompose and remove the colloidial and dissolved organic substances. Heather conditions including temperature,sun shine and duration, also pH and sensitization time, in addition to the nutrients as nitrogen and phosphate are some effective factors on its efficiency.This study is performed



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



Performance comparison of a pilot-scale UASB and DHS system and activated sludge process for the treatment of municipal wastewater.  


This study compares the performance of a pilot-scale combination of UASB and DHS system to that of activated sludge process (ASP) for the treatment of municipal sewage. Both systems were operated in parallel with the same sewage as influent. The study was conducted for more than 300 days, which revealed that organic removal efficiency of UASB+DHS system was comparable to that of ASP. Unfiltered BOD removal by both systems was more than 90%. However, UASB+DHS system outperformed ASP for pathogen removal. In addition, volume of excess sludge production from UASB+DHS was 15 times smaller than that from ASP. Moreover, unlike ASP, there is no requirement of aeration for the operation of UASB+DHS system, which makes it an economical treatment system. Considering the above observations, it was concluded that UASB+DHS system can be a cost-effective and viable option for the treatment of municipal sewage over ASP, especially for low-income countries. PMID:17418365

Tandukar, Madan; Ohashi, A; Harada, H



Wastewater Treatment I. Instructor's Manual.  

ERIC Educational Resources Information Center

This instructor's manual provides an outline and guide for teaching Wastewater Treatment I. It consists of nine sections. An introductory note and a course outline comprise sections 1 and 2. Section 3 (the bulk of the guide) presents lesson outlines for teaching the ten chapters of the manual entitled "Operation of Wastewater Treatment Plants."…

California Water Pollution Control Association, Sacramento. Joint Education Committee.


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


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



Methane emission during municipal wastewater treatment.  


Municipal wastewater treatment plants emit methane. Since methane is a potent greenhouse gas that contributes to climate change, the abatement of the emission is necessary to achieve a more sustainable urban water management. This requires thorough knowledge of the amount of methane that is emitted from a plant, but also of the possible sources and sinks of methane on the plant. In this study, the methane emission from a full-scale municipal wastewater facility with sludge digestion was evaluated during one year. At this plant the contribution of methane emissions to the greenhouse gas footprint were slightly higher than the CO? emissions related to direct and indirect fossil fuel consumption for energy requirements. By setting up mass balances over the different unit processes, it could be established that three quarters of the total methane emission originated from the anaerobic digestion of primary and secondary sludge. This amount exceeded the carbon dioxide emission that was avoided by utilizing the biogas. About 80% of the methane entering the activated sludge reactor was biologically oxidized. This knowledge led to the identification of possible measures for the abatement of the methane emission. PMID:22575155

Daelman, Matthijs R J; van Voorthuizen, Ellen M; van Dongen, Udo G J M; Volcke, Eveline I P; van Loosdrecht, Mark C M



Process for biological wastewater treatment  

SciTech Connect

For the biological purification of wastewater in a reactor in the presence of open-pore and compressible carrier material for biomass, the carrier material, prior to its use in the reactor, is loaded with bacteria, finely divided, inorganic and/or organic compounds, selected for wastewater purification, and is then either stored or used in the process, the loaded carrier being especially useful for decreasing the start-up time of a wastewater treatment plant.

Frydman, A.; Reimann, H.




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...


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))




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 ...



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...


Treated wastewater discharged from municipal wastewater treatment plants (WWTPs) contains  

E-print Network

Treated wastewater discharged from municipal wastewater treatment plants (WWTPs) contains to provide rapid, field-ready, inexpen- sive testing of these chemicals in wastewater is also needed estrogenic chemicals, and 2) develop sensor technology for the rapid measure- ment in wastewater of two key

Fay, Noah


Electrochemical technologies in wastewater treatment  

Microsoft Academic Search

This paper reviews the development, design and applications of electrochemical technologies in water and wastewater treatment. Particular focus was given to electrodeposition, electrocoagulation (EC), electroflotation (EF) and electrooxidation. Over 300 related publications were reviewed with 221 cited or analyzed. Electrodeposition is effective in recover heavy metals from wastewater streams. It is considered as an established technology with possible further development

Guohua Chen



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.




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...



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...



EPA Science Inventory

This two volume set presents in detail technical design information for the following sludge treatment and disposal processes: incineration, pyrolysis, composting, land utilization, and landfilling. The discussion of each process includes, where possible, a presentation of perfor...


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.


Is your wastewater toxic to the municipal treatment plant?  

SciTech Connect

For many reasons, it is beneficial to know whether or not wastewater generated from a manufacturing process is toxic or can inhibit the microorganisms in a municipal wastewater treatment plant. One simple way to test the wastewater is by using a laboratory respirometer, which can evaluate both toxicity and treatability. In some cases, respirometer use may save an industry thousands or even millions of dollars by proving that certain chemicals previously perceived to be detrimental are actually treatable in the municipal wastewater treatment plant. Because these chemicals will not cause any harm, the cost of a pretreatment plant is avoided. Of course, the reverse could be true when a municipality suspects wastewater discharged from an industry is causing an upset condition to its activated sludge wastewater treatment plant. Because toxicity and treatability are both functions of the respiration rate of microbial cells, a method that measures the respiration rate of microbial cells also can be used to measure toxicity. This article discusses several situations in which a respirometer was used to measure the toxicity and treatability of wastewater suspected to have a toxic effect on the municipal activated sludge plant.

Havash, J.; Oster, J. [Lockwood Green Technologies Inc., Atlanta, GA (United States)




E-print Network

and to regulate its use in such a way as to prevent harmful effects on soil, vegetation, ani- mals and man Commission Environ- ment DG, Sludge treatment: l Reduces organic ingredients-Norway treats source separated household waste (food waste), organic industrial waste (food processing


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



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.  


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



Cheese whey wastewater: characterization and treatment.  


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



Use of submerged anaerobic–anoxic–oxic membrane bioreactor to treat highly toxic coke wastewater with complete sludge retention  

Microsoft Academic Search

Coke wastewater is an extremely toxic industrial effluent that requires treatment before discharge. A bench-scale, anaerobic–anoxic–oxic membrane bioreactor (A1\\/A2\\/O-MBR) system was utilized to treat real coke wastewater with complete sludge retention. In a 160-d test, the A1\\/A2\\/O-MBR system stably removed 87.9±1.6% of chemical oxygen demand, 99.4±0.3% of turbidity, and 99.7±3.5% of NH4+-N from coke wastewater. The membrane rejected almost all

Wen-Tao Zhao; Xia Huang; Duu-Jong Lee; Xiao-Hui Wang; Yue-Xiao Shen




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...


In situ investigation of tubular microbial fuel cells deployed in an aeration tank at a municipal wastewater treatment plant  

E-print Network

wastewater treatment plant Fei Zhang a , Zheng Ge a , Julien Grimaud b , Jim Hurst b , Zhen He a: Microbial fuel cells Wastewater treatment Organic removal Aeration Activated sludge a b s t r a c of wastewater quality, and other operating conditions. Unlike prior lab stud- ies by others, the results


An expert system for monitoring and diagnosis of anaerobic wastewater treatment plants  

Microsoft Academic Search

In this paper, an expert system (ES) developed for the monitoring and diagnosis of anaerobic wastewater treatment plants (AWT), is presented. The system was evaluated in a hybrid pilot plant of 1.1m3 located in an industrial environment for the treatment of wastewaters from a fibreboard production factory. The reactor is a hybrid USBF, combining an upflow anaerobic sludge blanket (UASB)

A. Puñal; E. Roca; J. M. Lema




E-print Network

CHAPTER 1 STATE ESTIMATION FOR WASTEWATER TREATMENT PROCESSES O. Bernard1 , B. Chachuat2 , and J sensors (also called observers) for wastewater treatment plants (WWTPs). We give an overview in "Wastewater Quality Monitoring and Wastewater Quality Monitoring and Treatment, Philippe Quevauviller (Ed

Paris-Sud XI, Université de


Dedicated land disposal of wastewater sludge in south africa: leaching of trace elements and nutrients.  


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



Parameters affecting the formation of perfluoroalkyl acids during wastewater treatment.  


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



Treatment of dredged sludge by mechanical dehydration  

SciTech Connect

Sludge deposits in the water area damage the ecosystems and environments; their elimination has always been an urgent task for human communities. Generally, sludge deposits are dredged out of the bottom of the water area, transported to, and discharged at a large disposal area on land. Recently, however, it has become increasingly difficult to secure disposal areas and routes of speedy transportation for disposal of dredged sludge. Accordingly, there is an urgent need to reduce both the volume of dredged sludge and the size of the disposal area. This mechanical method is different from the conventional engineering dehydration by loading, consolidation, and drainage in that the dredged sludge is separated into sludge cakes and clean water that can be returned to the water area through mechanical centrifugal dehydration. Sludge deposits are distributed thin and wide on the bottom of the water area, and a pump dredge has been proved effective in many cases for dredging the upper layers of sludge deposits accurately and without creating turbidity in water. This mechanical sludge treatment technique can be most efficient when used in combination with a pump dredge. This method offers the following advantages: (a) It requires smaller space for treatment and disposal of dredged sludge than the conventional method. (b) Facilities and costs for transportation can be reduced. (c) Various systems can be adopted for transportation of sludge cakes. (d) This system is transportable and compact and can be constructed anywhere either on land or on water.

Maekawa, T.



Evaluation of reusing alum sludge for the coagulation of industrial wastewater containing mixed anionic surfactants.  


A coagulation-flocculation process is typically employed to treat the industrial wastewater generated by the consumer products industry manufacturing detergents, soaps, and others. The expenditure of chemicals including coagulants and chemicals for pH adjustment is costly for treating this wastewater. The objective of this study was to evaluate the feasibility of reusing the aluminum sulfate (alum) sludge as a coagulant or as a coagulation aid so that the fresh alum dosage can be minimized or the removal efficiency can be enhanced. The experiments were conducted in a jar-test apparatus simulating the coagulation-flocculation process for simultaneous removals of organic matters, anionic surfactants, suspended solids, and turbidity. At the optimum initial pH value of 10 and the fresh alum concentration of 400 mg/L, the total suspended solids (TSS), total chemical oxygen demand (TCOD), total anionic surfactants, and turbidity removal efficiencies were 71.5%, 76.4%, 95.4%, and 98.2%, respectively. The addition of alum sludge as a coagulant alone without any fresh alum addition could significantly remove the turbidity, TCOD, and anionic surfactants. The TSS was left in the supernatants after the settling period, but would subsequently be removed by adding the fresh alum. The TSS, TCOD, and turbidity removal efficiencies were also enhanced when both the alum sludge and the fresh alum were employed. The TCOD removal efficiency over 80% has been accomplished, which has never fulfilled by using the fresh alum alone. It is concluded that the alum sludge could be reused for the treatment of industrial wastewater generated by the consumer products industry. PMID:21793400

Jangkorn, Siriprapha; Kuhakaew, Sinchai; Theantanoo, Suwapee; Klinla-or, Harit; Sriwiriyarat, Tongchai



Phosphorus removal from synthetic and municipal wastewater using spent alum sludge.  


In the present study, phosphorus removal was studied using as coagulant spent alum sludge from a water treatment plant of EYDAP (Athens Water Supply and Sewerage Company) and compared to alum (Al2(SO4)3.18H2O), iron chloride (FeCl3.7H2O), iron sulfate (Fe2(S04).10H2O) and calcium hydroxide (Ca(OH)2) at a constant pH (equal to 6). The comparison was based on their efficiency to remove phosphorus in synthetic wastewater consisting of 10 mg/L P as potassium dihydrogen phosphate and 50 mg/L N as ammonium chloride, The experiments were carried out using a jar-test apparatus and the measurements were performed according to the Standard Methods for the Examination of Water and Wastewater. Pure alum, iron chloride and iron sulfate were much more efficient in phosphorus removal than the spent alum sludge but in the case of calcium hydroxide, phosphorus removal was very low in pH = 6. Specifically, orthophosphate were totally removed by alum using 15 mg/L as Al, by alum sludge using 75 mg/L as Al and by FeCl3.7H2O or Fe2(SO4).10H2O using 30 mg/L of Fe while in the case of calcium hydroxide P removal was actually zero. pH measurements showed that the uptake of phosphates is associated to the release of OH ions in the solution and that the end of P uptake is accompanied by the stabilization of pH. Finally this spent alum sludge was tested on municipal wastewater and proved to be effective as apart from phosphorus it was shown to remove turbidity and COD. PMID:16459830

Georgantas, D A; Grigoropoulou, H P



Biological treatment of shrimp production wastewater.  


Over the last few decades, there has been an increase in consumer demand for shrimp, which has resulted in its worldwide aquaculture production. In the United States, the stringent enforcement of environmental regulations encourages shrimp farmers to develop new technologies, such as recirculating raceway systems. This is a zero-water exchange system capable of producing high-density shrimp yields. The system also produces wastewater characterized by high levels of ammonia, nitrate, nitrite, and organic carbon, which make waste management costs prohibitive. Shrimp farmers have a great need for a waste management method that is effective and economical. One such method is the sequencing batch reactor (SBR). A SBR is a variation of the activated sludge biological treatment process. This process uses multiple steps in the same reactor to take the place of multiple reactors in a conventional treatment system. The SBR accomplishes equalization, aeration, and clarification in a timed sequence in a single reactor system. This is achieved through reactor operation in sequences, which includes fill, react, settle, decant, and idle. A laboratory scale SBR was successfully operated using shrimp aquaculture wastewater. The wastewater contained high concentrations of carbon and nitrogen. By operating the reactors sequentially, namely, aerobic and anoxic modes, nitrification and denitrification were achieved as well as removal of carbon. Ammonia in the waste was nitrified within 4 days. The denitrification of nitrate was achieved by the anoxic process, and 100% removal of nitrate was observed within 15 days of reactor operation. PMID:19396482

Boopathy, Raj



Thermophilic biological nitrogen removal in industrial wastewater treatment.  


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



Occurrence, Transformation, and Fate of Antibiotics in Municipal Wastewater Treatment Plants  

Microsoft Academic Search

Occurrence, transformation, and fate of antibiotics in municipal wastewater treatment plants (WWTPs) are becoming an emerging environmental research area. As pseudopersistent pollutants, antibiotics belonging to 6 classes (i.e., ?-lactams, sulfonamides, quinolones, tetracyclines, macrolides, and others) have been frequently detected in sewage, activated sludge, digested sludge, and effluents. The authors summarized the latest information on occurrence, transformation, and fate of antibiotics

Tong Zhang; Bing Li




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



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)



Biological treatment and nanofiltration of denim textile wastewater for reuse.  


This study aims at coupling of activated sludge treatment with nanofiltration to improve denim textile wastewater quality to reuse criteria. In the activated sludge reactor, the COD removal efficiency was quite high as it was 91+/-2% and 84+/-4% on the basis of total and soluble feed COD, respectively. The color removal efficiency was 75+/-10%, and around 50-70% of removed color was adsorbed on biomass or precipitated within the reactor. The high conductivity of the wastewater, as high as 8 mS/cm, did not adversely affect system performance. Although biological treatment is quite efficient, the wastewater does not meet the reuse criteria. Hence, further treatment to improve treated water quality was investigated using nanofiltration. Dead-end microfiltration (MF) with 5 microm pore size was applied to remove coarse particles before nanofiltration. The color rejection of nanofiltration was almost complete and permeate color was always lower than 10 Pt-Co. Similarly, quite high rejections were observed for COD (80-100%). Permeate conductivity was between 1.98 and 2.67 mS/cm (65% conductivity rejection). Wastewater fluxes were between 31 and 37 L/m2/h at 5.07 bars corresponding to around 45% flux declines compared to clean water fluxes. In conclusion, for denim textile wastewaters nanofiltration after biological treatment can be applied to meet reuse criteria. PMID:17976906

Sahinkaya, Erkan; Uzal, Nigmet; Yetis, Ulku; Dilek, Filiz B



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



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.




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...


Ahmet H. Aydilek, 1 Tuncer B. Edil, 1 Patrick J. Fox2 Consolidation Characteristics of Wastewater Sludge  

E-print Network

Ahmet H. Aydilek, 1 Tuncer B. Edil, 1 Patrick J. Fox2 Consolidation Characteristics of Wastewater., Edil, T. B., and Fox, P. J., "Consolidation Characteristics of Wastewater Sludge", Geotechnics of High wastewater sludge. Small and large-scale laboratory consolidation tests were conducted and field observations

Aydilek, Ahmet


Elimination of selected acidic pharmaceuticals from municipal wastewater by an activated sludge system and membrane bioreactors.  


The elimination of six acidic pharmaceuticals (clofibric acid, diclofenac, ibuprofen, ketoprofen, mefenamic acid, and naproxen) in a real wastewater treatment plant (WWTP) using an activated sludge system and membrane bioreactors (MBRs) was investigated by using a gas chromatography/mass spectrometry (GC/MS) system for measurement of the compounds. Limited information is available for some of the tested pharmaceuticals at present. Solid retention times (SRTs) of the WWTP and the two MBRs were 7, 15, and 65 days, respectively. The elimination rates varied from compound to compound. The MBRs exhibited greater elimination rates for the examined pharmaceuticals than did the real plant. Dependency of the elimination rates of the pharmaceuticals on SRTs was obvious; the MBR operated with a longer SRT of 65 days clearly showed better performance than did the MBR with a shorter SRT of 15 days. The difference between the two MBRs was particularly significant in terms of elimination of ketoprofen and diclofenac. Measurements of the amounts of adsorbed pharmaceuticals on the sludge and aerobic batch elimination experiments were carried out to investigate the elimination pathways of the pharmaceuticals. Results of the batch elimination tests revealed that the sludges in the MBRs had large specific sorption capacities mainly due to their large specific surface areas. Despite the sorption capacities of sludges, the main mechanism of elimination of the pharmaceuticals in the investigated processes was found to be biodegradation. Biodegradation of diclofenac, which has been believed to be refractory to biodegradation, seemed to occur very slowly. PMID:17547201

Kimura, Katsuki; Hara, Hiroe; Watanabe, Yoshimasa



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.



Anaerobic treatment of brewery wastewater with an internal membrane bioreactor.  


Anaerobic treatment is growing very popular these days because of low sludge production compared to activated sludge processes. The drawback of the process is the risk of sludge washout, especially when the formation of granular sludge is not expected. By using an internal anaerobic bioreactor this problem can be overcome. A lab scale internal anaerobic membrane bioreactor was operated at SEGHERSbetter technology for Water N.V. to which brewery wastewater was fed (COD=2300 mg/l). Hollow fibres were inserted into the anaerobic bioreactor, from which the effluent was extracted by underpressure. The COD-removal was excellent and very constant at a value of 95%. No suspended solids were present in the effluent. The membrane permeability stabilised at relatively low value of 18 l/ due to an irreversible adhesion of constituents in the bioreactor. No growth of biomass was found during two months of operation. Inocculated granular sludge fell apart into loose flocs within several weeks of the startup, not affecting biological performance. The internal anaerobic membrane bioreactor is a promising new area within the field of wastewater treatment. It is expected that this process will have an important future. PMID:15954573

Cornelissen, E R; van Buggenhout, S; van Ermen, S; De Smedt, M; Van Impe, J; Koning, J



Use of wastewater sludge as a raw material for production of L-lactic acid  

SciTech Connect

This study utilizes wastewater sludges to produce L-lactic acid, a precursor of biodegradable plastic. The high concentrations of cellulose contained in the sludge, derived from a paper manufacturing facility, have been found to be convertible to L-lactic acid at a rate as high as 6.91 g/L. To achieve such a high conversion rate, the sludge must be pretreated with cellulase. This pretreatment includes inoculation of the sludge with lactic acid bacteria, strain LA1, after the sludge has been subjected to enzymatic hydrolysis.

Nakasaki, Kiyohiko; Akakura, Naoki; Adachi, Tomohiko; Akiyama, Tetsuo [Shizuoka Univ. (Japan). Dept. of Materials Science and Chemical Engineering] [Shizuoka Univ. (Japan). Dept. of Materials Science and Chemical Engineering



Aerobic domestic waste water treatment in a pilot plant with complete sludge retention by cross-flow filtration  

Microsoft Academic Search

An aerobic wastewater treatment pilot plant with cross-flow filtration was operated for more than 300 days to examine whether reduced sludge production and stable treatment performance can be achieved when sludge is completely retained. The volumetric loads ranged between 0.9 and 2.0 g COD·1?1·day?1. Technical observations were: the oxygen transfer rate became poor at high sludge concentrations; membrane capacities declined

E. B. Muller; A. H. Stouthamer; H. W. van Verseveld; D. H. Eikelboom



The survival of pathogens in soil treated with wastewater sludge and in potatoes grown in such soil.  


The prevalence of pathogens on potatoes (Solanum tuberosum) grown in soil amended with a pathogen rich wastewater sludge was investigated. Bacteria of the family Enterobacteriaceae are important pathogens causing intestinal and systemic illness of humans and other animals. Type B sludge was used. Sludges investigated are the high metal and the low metal sludges. Microorganisms in the sludge-amended soil were using culture-based technique. Salmonella and E. coli were observed in tested soil samples. No microorganisms were isolated from control samples taken throughout the process of the experiment. At harvest time, some of the potato samples from LMS soil were contaminated. These potatoes were subjected to further investigation using molecular techniques (polymerase chain reaction) with fD1 and rP2 as primers. Organisms identified from the sequenced potato peel samples with the BLAST search tool included Enterobacter agglomerans (Pantoea agglomerans), several Buttiauxella spp., Pectobacterium spp., Erwinia spp. and a few Pantoea spp. Other than the E. agglomerans, which is commonly found in the gut and upper respiratory tract of humans and in the environment, all the other species identified were found to be mainly either plant or soil pathogens. The E. agglomerans are not primary pathogens but secondary opportunistic pathogens particularly in immunocompromised individuals. These results suggest that growing high risk crops using wastewater sludge contaminated soil may lead to limited infestation of produce with primary pathogens. It appears that the use of HMS due to early pathogen die-off provides less risk of infection than the LMS. However, proper treatment of wastewater sludge to reduce pathogen load is essential prior to its use as soil conditioner. PMID:17087382

Chale-Matsau, J R B; Snyman, H G




E-print Network

CHAPTER 1 STATE ESTIMATION FOR WASTEWATER TREATMENT PROCESSES O. Bernard1 , B. Chachuat2 , and J sensors (also called observers) for wastewater treatment plants (WWTPs). We give an overview model description (e.g., the 1 #12;2 STATE ESTIMATION FOR WASTEWATER TREATMENT PROCESSES extended Kalman

Bernard, Olivier


Wastewater Treatment I. Student's Guide.  

ERIC Educational Resources Information Center

This student's guide is designed to provide students with the job skills necessary for the safe and effective operation and maintenance of wastewater treatment plants. It consists of three sections. Section 1 consists of an introductory note outlining course objectives and the format of the guide. A course outline constitutes the second section.…

California Water Pollution Control Association, Sacramento. Joint Education Committee.



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



EPA Science Inventory

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 their juice. The juice is fe...



Microsoft Academic Search

Ten filamentous fungi adapted to domestic wastewater sludge (DWS) were further studied to evaluate their potential in terms of adaptation to higher sludge supplemented growing media and phytopathogenicity (induction of diseases to plants) to three germinating crop (Corn: Zea mays, Mung bean: Phaseolus aureus and Mustard: Brassica napus) seeds. The performances of the fungi in seed germination were evaluated based

Abul Hossain Molla; Ahmadun Fakhrul-Razi; Mohamed Musa Hanafi; Suraini Abd-Aziz



Application of the SCADA system in wastewater treatment plants.  


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



Electrochemical treatment of industrial wastewater.  


This paper presents the results of the treatment of phenolic compounds containing wastewater generated from phenol-formaldehyde resin manufacturing, oil refinery and bulk drug manufacturing industries by electrochemical method. Experiments were conducted at a fixed current density of 5.4 A/dm2 using Ti/TiO2-RuO2-IrO2 electrode and an undivided reactor. During the various stages of electrolysis, parameters such as COD and TOC concentrations were determined in order to know the feasibility of electrochemical treatment. Adsorbable organic halogens (AOX) were detected at high concentrations during the electrolytic treatment of the effluents. However, it was observed that increasing the electrolysis time bring down the AOX concentration to lower levels. Energy consumption and current efficiency during the electrolysis were calculated and presented. The present study proves the effectiveness of electrochemical treatment for highly concentrated bio-refractory organic pollutants present in the industrial wastewater. PMID:15363521

Rajkumar, D; Palanivelu, K



Diversity and enrichment of nitrite-dependent anaerobic methane oxidizing bacteria from wastewater sludge.  


Recently discovered microorganisms affiliated to the bacterial phylum NC10, named "Candidatus Methylomirabilis oxyfera", perform nitrite-dependent anaerobic methane oxidation. These microorganisms could be important players in a novel way of anaerobic wastewater treatment where ammonium and residual dissolved methane might be removed at the expense of nitrate or nitrite. To find suitable inocula for reactor startup, ten selected wastewater treatment plants (WWTPs) located in The Netherlands were screened for the endogenous presence of M. oxyfera using molecular diagnostic methods. We could identify NC10 bacteria with 98% similarity to M. oxyfera in nine out of ten WWTPs tested. Sludge from one selected WWTP was used to start a new enrichment culture of NC10 bacteria. This enrichment was monitored using specific pmoA primers and M. oxyfera cells were visualized with fluorescence oligonucleotide probes. After 112 days, the enrichment consumed up to 0.4 mM NO(2)(-) per day. The results of this study show that appropriate sources of biomass, enrichment strategies, and diagnostic tools existed to start and monitor pilot scale tests for the implementation of nitrite-dependent methane oxidation in wastewater treatment at ambient temperature. PMID:21667086

Luesken, Francisca A; van Alen, Theo A; van der Biezen, Erwin; Frijters, Carla; Toonen, Ger; Kampman, Christel; Hendrickx, Tim L G; Zeeman, Grietje; Temmink, Hardy; Strous, Marc; Op den Camp, Huub J M; Jetten, Mike S M



Protozoa in wastewater treatment processes: A minireview  

Microsoft Academic Search

Biological wastewater treatment is a process of increasing importance in a world with an ever-increasing human population. Wastewater treatment facilities are designed to maintain the high density and activity levels of those microorganisms that carry out the various purification processes. Protozoa are one of the most common components in these man-made ecosystems and play an important role in wastewater purification

P. Madoni



Orientation to Municipal Wastewater Treatment. Training Manual.  

ERIC Educational Resources Information Center

Introductory-level material on municipal wastewater treatment facilities and processes is presented. Course topics include sources and characteristics of municipal wastewaters; objectives of wastewater treatment; design, operation, and maintenance factors; performance testing; plant staffing; and laboratory considerations. Chapter topics include…

Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.


Onsite Wastewater Treatment Systems: Ultraviolet Light Disinfection  

E-print Network

Some onsite wastewater treatment systems include a disinfection component. This publication explains how homeowners can disinfect wastewater with ultraviolet light, what the components of such a system are, what factors affect the performance of a...

Lesikar, Bruce J.



Treating Sludges  

ERIC Educational Resources Information Center

Discussed are some of the ways to handle municipal and industrial wastewater treatment sludge presented at the 1978 American Chemical Society meeting. Suggestions include removing toxic materials, recovering metals, and disposing treated sewage sludge onto farm land. Arguments for and against land use are also given. (MA)

Josephson, Julian



Optimization of Ozonation Process for the Reduction of Excess Sludge Production from Activated Sludge Process of Sago Industry Wastewater Using Central Composite Design  

PubMed Central

Sago industries effluent containing large amounts of organic content produced excess sludge which is a serious problem in wastewater treatment. In this study ozonation has been employed for the reduction of excess sludge production in activated sludge process. Central composite design is used to study the effect of ozone treatment for the reduction of excess sludge production in sago effluent and to optimise the variables such as pH, ozonation time, and retention time. ANOVA showed that the coefficient determination value (R2) of VSS and COD reduction were 0.9689 and 0.8838, respectively. VSS reduction (81%) was achieved at acidic pH 6.9, 12 minutes ozonation, and retention time of 10 days. COD reduction (87%) was achieved at acidic pH 6.7, 8 minutes of ozonation time, and retention time of 6 days. Low ozonation time and high retention time influence maximum sludge reduction, whereas low ozonation time with low retention time was effective for COD reduction. PMID:22593666

Subha, B.; Muthukumar, M.



Membrane bio-reactor for textile wastewater treatment plant upgrading.  


Textile industries carry out several fiber treatments using variable quantities of water, from five to forty times the fiber weight, and consequently generate large volumes of wastewater to be disposed of. Membrane Bio-reactors (MBRs) combine membrane technology with biological reactors for the treatment of wastewater: micro or ultrafiltration membranes are used for solid-liquid separation replacing the secondary settling of the traditional activated sludge system. This paper deals with the possibility of realizing a new section of one existing WWTP (activated sludge + clariflocculation + ozonation) for the treatment of treating textile wastewater to be recycled, equipped with an MBR (76 l/s as design capacity) and running in parallel with the existing one. During a 4-month experimental period, a pilot-scale MBR proved to be very effective for wastewater reclamation. On average, removal efficiency of the pilot plant (93% for COD, and over 99% for total suspended solids) was higher than the WWTP ones. Color was removed as in the WWTP. Anionic surfactants removal of pilot plant was lower than that of the WWTP (90.5 and 93.2% respectively), while the BiAS removal was higher in the pilot plant (98.2 vs. 97.1). At the end cost analysis of the proposed upgrade is reported. PMID:16235750

Lubello, C; Gori, R



Enrichment of denitrifying methanotrophic bacteria from municipal wastewater sludge in a membrane bioreactor at 20°C.  


Simultaneous nitrogen and methane removal by the slow growing denitrifying methanotrophic bacterium 'Candidatus Methylomirabilis oxyfera' offers opportunities for a new approach to wastewater treatment. However, volumetric nitrite consumption rates should be increased by an order of magnitude before application in wastewater treatment becomes possible. A maximum volumetric nitrite consumption rate of 36 mg NO2(-)-N/L d was achieved in a membrane bioreactor inoculated with wastewater sludge and operated at 20°C. This rate is similar to maximum rates reported in literature, though it was thought that by strict biomass retention using membranes, higher rates would be achieved. In experiments lasting several years, growth was not stable: every experiment showed a decrease in activity after 1-2 years. The cause remains unknown. Rates increased after addition of copper and operating a membrane bioreactor at shorter hydraulic retention times. Further research should focus on long-term effects of copper addition and operation at hydraulic retention times in the order of hours using membrane bioreactors. PMID:24809733

Kampman, Christel; Temmink, Hardy; Hendrickx, Tim L G; Zeeman, Grietje; Buisman, Cees J N



Fossil organic carbon in wastewater and its fate in treatment plants.  


This study reports the presence of fossil organic carbon in wastewater and its fate in wastewater treatment plants. The findings pinpoint the inaccuracy of current greenhouse gas accounting guidelines which defines all organic carbon in wastewater to be of biogenic origin. Stable and radiocarbon isotopes ((13)C and (14)C) were measured throughout the process train in four municipal wastewater treatment plants equipped with secondary activated sludge treatment. Isotopic mass balance analyses indicate that 4-14% of influent total organic carbon (TOC) is of fossil origin with concentrations between 6 and 35 mg/L; 88-98% of this is removed from the wastewater. The TOC mass balance analysis suggests that 39-65% of the fossil organic carbon from the influent is incorporated into the activated sludge through adsorption or from cell assimilation while 29-50% is likely transformed to carbon dioxide (CO2) during secondary treatment. The fossil organic carbon fraction in the sludge undergoes further biodegradation during anaerobic digestion with a 12% decrease in mass. 1.4-6.3% of the influent TOC consists of both biogenic and fossil carbon is estimated to be emitted as fossil CO2 from activated sludge treatment alone. The results suggest that current greenhouse gas accounting guidelines, which assume that all CO2 emission from wastewater is biogenic may lead to underestimation of emissions. PMID:23863394

Law, Yingyu; Jacobsen, Geraldine E; Smith, Andrew M; Yuan, Zhiguo; Lant, Paul



Humic substances in bioremediation of industrial wastewater - mitigation of inhibition of activated sludge caused by phenol and formaldehyde.  


This paper describes studies on the effect of humic substances on bioremediation of industrial wastewater, heavily contaminated with formaldehyde and phenol, using aerobic respirometry. Returned activated sludge (RAS) was the source of biomass. Respirometric data and non-linear regression analysis indicated that the system complied with the Haldane model for inhibitory wastes. It has been found that an addition of humate at the dose of 2000 mg/L substantially reduced this inhibitory effect, resulting in an increase of biological oxygen uptake and in a better removal of both, phenol and formaldehyde. The results show that an application of humic substances to mitigate an inhibition of the activated sludge in wastewater treatment plants may be an attractive alternative to the use of activated carbon or specialized sorbents. PMID:18393070

Lipczynska-Kochany, Ewa; Kochany, Jan



Activated Sludge.  

ERIC Educational Resources Information Center

Presents the 1978 literature review of wastewater treatment. This review covers: (1) activated sludge process; (2) process control; (3) oxygen uptake and transfer; (4) phosphorus removal; (5) nitrification; (6) industrial wastewater; and (7) aerobic digestion. A list of 136 references is also presented. (HM)

Saunders, F. Michael



Activated sludge studies of selected contaminants of PFH wastewater  

SciTech Connect

Acetone, propionitrile, pyrrole, and thiocyanate were selected as representative compounds of wastewater expected from pressurized, fluidized-bed hydroretorting (PFH) of Eastern oil shales. The PFH process has been the subject of investigation by the Institute of Gas Technology, under contract with the United States Department of Energy, for the purpose of obtaining higher oil yields from Eastern shales than has been possible using conventional retorting methods. Preliminary batch experiments illustrated that acetone, propionitrile, pyrrole, and thiocyanate are aerobically biodegradable by heterogeneous microbiological cultures. Three continuous flow activated sludge reactors were used to further evaluate the biological treatability of the synthetic waste. The studies revealed that the compounds could be removed at hydraulic residence times of as low as one day. Three one-day experiments demonstrated that biological system's capability to accept organic shock loadings without a change in effluent quality. A no-recycle reactor illustrated that the flocculent microbiological population had a high resistance to solids washout. Because a supplementary nitrogen source was not included in synthetic waste treated by the no-recycle unit, it was shown that propionitrile, pyrrole, and/or thiocyanate supplied the nitrogen necessary for biological activity.

Dudley, S.K. (Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)); Bustamante, R.B.; Bonner, W.P. (Tennessee Technological Univ., Cookeville, TN (United States))



Activated sludge studies of selected contaminants of PFH wastewater  

SciTech Connect

Acetone, propionitrile, pyrrole, and thiocyanate were selected as representative compounds of wastewater expected from pressurized, fluidized-bed hydroretorting (PFH) of Eastern oil shales. The PFH process has been the subject of investigation by the Institute of Gas Technology, under contract with the United States Department of Energy, for the purpose of obtaining higher oil yields from Eastern shales than has been possible using conventional retorting methods. Preliminary batch experiments illustrated that acetone, propionitrile, pyrrole, and thiocyanate are aerobically biodegradable by heterogeneous microbiological cultures. Three continuous flow activated sludge reactors were used to further evaluate the biological treatability of the synthetic waste. The studies revealed that the compounds could be removed at hydraulic residence times of as low as one day. Three one-day experiments demonstrated that biological system`s capability to accept organic shock loadings without a change in effluent quality. A no-recycle reactor illustrated that the flocculent microbiological population had a high resistance to solids washout. Because a supplementary nitrogen source was not included in synthetic waste treated by the no-recycle unit, it was shown that propionitrile, pyrrole, and/or thiocyanate supplied the nitrogen necessary for biological activity.

Dudley, S.K. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States); Bustamante, R.B.; Bonner, W.P. [Tennessee Technological Univ., Cookeville, TN (United States)



Use of the Static Granular Bed Reactor (SGBR) with anaerobic sludge to treat poultry slaughterhouse wastewater and kinetic modeling.  


Poultry slaughterhouses discharge very high amount of wastewaters and these wastewaters can be treated successfully at a very low cost using anaerobic treatment. In this study, the Static Granular Bed Reactor (SGBR), a newly developed anaerobic process which is fully anaerobic granule, and another Static Granular Bed Reactor containing both anaerobic granular biomass and non-granular biomass were employed for the treatment of poultry slaughterhouse wastewater. The objective of the use of two reactors having different types of anaerobic biomass is to evaluate whether anaerobic sludge could be used effectively instead of anaerobic granule, which is much more difficult to obtain than the other during the start up period. Average COD removal efficiencies were greater than 95% for both of the reactors. Furthermore, Grau second-order and modified Stover-Kincannon models were successfully used to develop a kinetic model of the experimental data with a high correlation coefficient (R(2)>0.95). PMID:19208468

Debik, E; Coskun, T



Evaluation of Water Treatment Sludge for Ameliorating Acid Mine Waste  

Microsoft Academic Search

ter providing authority to the Gauteng Province (South Africa), produces 550 Mg of water treatment sludge This study investigated the liming effect of water treatment sludge daily. The reuse of sludge will therefore be environmen- on acid mine spoils. The study was conducted with sludge from a tally and economically beneficial. Alternative uses of the water purification plant along the

L. Van Rensburg; T. L. Morgenthal



A modified anaerobic digestion process with chemical sludge pre-treatment and its modelling.  


Activated Sludge Models (ASMs) assume an unbiodegradable organic particulate fraction in the activated sludge, which is derived from the decay of active microorganisms in the sludge and/or introduced from wastewater. In this study, a seasonal change of such activated sludge constituents in a municipal wastewater treatment plant was monitored for 1.5 years. The chemical oxygen demand ratio of the unbiodegradable particulates to the sludge showed a sinusoidal pattern ranging from 40 to 65% along with the change of water temperature in the plant that affected the decay rate. The biogas production in a laboratory-scale anaerobic digestion (AD) process was also affected by the unbiodegradable fraction in the activated sludge fed. Based on the results a chemical pre-treatment using H2O2 was conducted on the digestate to convert the unbiodegradable fraction to a biodegradable one. Once the pre-treated digestate was returned to the digester, the methane conversion increased up to 80% which was about 2.4 times as much as that of the conventional AD process, whilst 96% of volatile solids in the activated sludge was digested. From the experiment, the additional route of the organic conversion processes for the inert fraction at the pre-treatment stage was modelled on the ASM platform with reasonable simulation accuracy. PMID:24901631

Hai, N M; Sakamoto, S; Le, V C; Kim, H S; Goel, R; Terashima, M; Yasui, H



Anaerobic treatment of fibreboard manufacturing wastewaters in a pilot scale hybrid usbf reactor  

Microsoft Academic Search

The treatment of fibreboard manufacturing (FBM) wastewaters was carried out in an industrial pilot plant, which consisted of a hybrid upflow sludge bed filter (USBF) anaerobic reactor and a coagulation–flocculation unit as a pre-treatment. COD removal efficiencies of 90–93% were attained in the anaerobic reactor operating at 37°C at organic loading rates (OLR) of 6.5–8.5kgCOD\\/m3d. Flocculant sludges were used as

José M. Fernández; Francisco Omil; Ramón Méndez; Juan M. Lema



Non-woven fabric filter separation activated sludge reactor for domestic wastewater reclamation.  


A non-woven fabric filter was experimentally evaluated for solid-liquid separation in an activated sludge reactor as an alternative membrane. A polypropylene fabric filter (70, 50 and 35 g/m2) was used for the experiment. The pilot system was operated in A/O (Anaerobic/Oxic) type in which the filter module was submerged into the oxic compartment. The filtration module consists of 10 plate type rectangular filter elements with effective filtration area, 2 m2. Gravity filtration was carried out for solid-liquid separation by changing the water head 0.05-0.5 m without backwashing during the system operation. Initial permeate flux was set at 0.4 m/d. C/N ratio of raw wastewater was controlled at 4.5 in terms of BOD/T-N. The fabric filter system showed a good performance enough for domestic wastewater treatment. Effluent solid concentration was 3.2 mg/L (93.5% removal). COD removal efficiency was 91.6% producing an effluent concentration around 13 mg/L. 66% of total nitrogen removal could be obtained at the adjusted C/N ratio of influent wastewater. However phosphorus removal was very low at 23%. It was found that the initial flux of 0.4 m/d should be maintained for stable performance of the system. PMID:12578185

Seo, G T; Moon, B H; Lee, T S; Lim, T J; Kim, I S



Carbon wastewater treatment process  

NASA Technical Reports Server (NTRS)

A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.



Activated-sludge process: Waste treatment. (Latest citations from the biobusiness database). Published Search  

SciTech Connect

The bibliography contains citations concerning the use of the activated sludge process in waste and wastewater treatment. Topics include biochemistry of the activated sludge process, effects of various pollutants on process activity, effects of environmental variables such as oxygen and water levels, and nutrient requirements of microorganisms employed in activated sludge processes. The citations also explore use of the process to treat specific wastes, such as halocarbons, metallic wastes, and petrochemical effluents; and wastes from pharmaceutical and dairy processes. (Contains 250 citations and includes a subject term index and title list.)

Not Available



Activated sludge process: Waste treatment. (Latest citations from the Biobusiness database). Published Search  

SciTech Connect

The bibliography contains citations concerning the use of the activated sludge process in waste and wastewater treatment. Topics include biochemistry of the activated sludge process, effects of various pollutants on process activity, effects of environmental variables such as oxygen and water levels, and nutrient requirements of microorganisms employed in activated sludge processes. The citations also explore use of the process to treat specific wastes, such as halocarbons, metallic wastes, and petrochemical effluents; and wastes from pharmaceutical and dairy processes. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)




Activated sludge process: Waste treatment. (Latest citations from the Biobusiness database). Published Search  

SciTech Connect

The bibliography contains citations concerning the use of the activated sludge process in waste and wastewater treatment. Topics include biochemistry of the activated sludge process, effects of various pollutants on process activity, effects of environmental variables such as oxygen and water levels, and nutrient requirements of microorganisms employed in activated sludge processes. The citations also explore use of the process to treat specific wastes, such as halocarbons, metallic wastes, and petrochemical effluents; and wastes from pharmaceutical and dairy processes. (Contains 250 citations and includes a subject term index and title list.)

Not Available



Activated sludge process: Waste treatment. (Latest citations from the Biobusiness database). Published Search  

SciTech Connect

The bibliography contains citations concerning the use of the activated sludge process in waste and wastewater treatment. Topics include biochemistry of the activated sludge process, effects of various pollutants on process activity, effects of environmental variables such as oxygen and water levels, and nutrient requirements of microorganisms employed in activated sludge processes. The citations also explore use of the process to treat specific wastes, such as halocarbons, metallic wastes, and petrochemical effluents; and wastes from pharmaceutical and dairy processes. (Contains 250 citations and includes a subject term index and title list.)

Not Available



Bioelectrochemical enhancement of anaerobic methanogenesis for high organic load rate wastewater treatment in a up-flow anaerobic sludge blanket (UASB) reactor  

PubMed Central

A coupling process of anaerobic methanogenesis and electromethanogenesis was proposed to treat high organic load rate (OLR) wastewater. During the start-up stage, acetate removal efficiency of the electric-biological reactor (R1) reached the maximization about 19 percentage points higher than that of the control anaerobic reactor without electrodes (R2), and CH4 production rate of R1 also increased about 24.9% at the same time, while additional electric input was 1/1.17 of the extra obtained energy from methane. Coulombic efficiency and current recorded showed that anodic oxidation contributed a dominant part in degrading acetate when the metabolism of methanogens was low during the start-up stage. Along with prolonging operating time, aceticlastic methanogenesis gradually replaced anodic oxidation to become the main pathway of degrading acetate. When the methanogens were inhibited under the acidic conditions, anodic oxidation began to become the main pathway of acetate decomposition again, which ensured the reactor to maintain a stable performance. FISH analysis confirmed that the electric field imposed could enrich the H2/H+-utilizing methanogens around the cathode to help for reducing the acidity. This study demonstrated that an anaerobic digester with a pair of electrodes inserted to form a coupling system could enhance methanogenesis and reduce adverse impacts. PMID:25322701

Zhao, Zhiqiang; Zhang, Yaobin; Chen, Shuo; Quan, Xie; Yu, Qilin



Bioelectrochemical enhancement of anaerobic methanogenesis for high organic load rate wastewater treatment in a up-flow anaerobic sludge blanket (UASB) reactor.  


A coupling process of anaerobic methanogenesis and electromethanogenesis was proposed to treat high organic load rate (OLR) wastewater. During the start-up stage, acetate removal efficiency of the electric-biological reactor (R1) reached the maximization about 19 percentage points higher than that of the control anaerobic reactor without electrodes (R2), and CH4 production rate of R1 also increased about 24.9% at the same time, while additional electric input was 1/1.17 of the extra obtained energy from methane. Coulombic efficiency and current recorded showed that anodic oxidation contributed a dominant part in degrading acetate when the metabolism of methanogens was low during the start-up stage. Along with prolonging operating time, aceticlastic methanogenesis gradually replaced anodic oxidation to become the main pathway of degrading acetate. When the methanogens were inhibited under the acidic conditions, anodic oxidation began to become the main pathway of acetate decomposition again, which ensured the reactor to maintain a stable performance. FISH analysis confirmed that the electric field imposed could enrich the H2/H(+)-utilizing methanogens around the cathode to help for reducing the acidity. This study demonstrated that an anaerobic digester with a pair of electrodes inserted to form a coupling system could enhance methanogenesis and reduce adverse impacts. PMID:25322701

Zhao, Zhiqiang; Zhang, Yaobin; Chen, Shuo; Quan, Xie; Yu, Qilin



Reuse Water Treatment Sludge for Hollow Concrete Block Manufacture  

Microsoft Academic Search

Problem statement: This research reuses the water treatment sludge fro m a water treatment plant to make hollow concrete blocks. The main objectives are to increase the value of the water treatment sludge from a water treatment plant and t o make a sustainable and profitable disposal alternative for the water treatment sludge. Attempt s were made to utilize the

Thaniya Kaosol


Self-heating of dried industrial wastewater sludge: lab-scale investigation of supporting conditions.  


We studied the reactivity of dried sludge produced by treatment of wastewater, mainly from tanneries. The solids transformations have been first characterized with thermal analysis (TGA and DSC) proving that exothermic transformation takes place at fairly low temperature, before the total organic combustion that occurs in air above 400°C. The onset of low temperature reactions depends on the heating rate and it can be below 100°C at very small heating rate. Then, we reproducibly determined the conditions to trigger dried sludge self-heating at the laboratory scale, on samples in the 0.2-0.3 kg size. Thermal insulation, some aeration and addition of water are key factors. Mastering the self-heating at this scale allows more detailed investigations as well as manipulation of conditions, to understand its nature, course and remediation. Here we report proves and discussions on the role of air, water, particle size, porosity and biological activity, as well as proving that also dried sludge from similar sources lead to self-heating. Tests demonstrate that air and water are simultaneously required for significant self-heating to occur. They act in diverging directions, both triggering the onset of the reactions and damping the temperature rise, by supporting heat loss. The higher the O2 concentration, the higher the solids heating rate. More added water prolongs the exothermic phase. Further additions of water can reactivate the material. Water emphasizes the exothermic processes, but it is not sufficient to start it in an air-free atmosphere. The initial solid moisture concentration (between 8% and 15%) affects the onset of self-heating as intuitive. The sludge particles size strongly determines the strength and extent of the heat release, indicating that surface reactions are taking place. In pelletized particles, limitations to water and air permeability mitigates the reaction course. PMID:23490357

Della Zassa, M; Biasin, A; Zerlottin, M; Refosco, D; Canu, P




E-print Network

94/0169 A STUDY OF ACTIVATED SLUDGE DEWATERING IN EXPERIMENTAL REED-PLANTED OR UNPLANTED SLUDGE study; reeds; sludge dewatering; sludge drying beds; small wastewater treatment plants. INTRODUCTION). It was of interest to confirm this aptitude for dewatering sludge from extended aeration plants, a medium

Paris-Sud XI, Université de


An expert system for monitoring and diagnosis of anaerobic wastewater treatment plants.  


In this paper, an expert system (ES) developed for the monitoring and diagnosis of anaerobic wastewater treatment plants (AWT), is presented. The system was evaluated in a hybrid pilot plant of 1.1 m3 located in an industrial environment for the treatment of wastewaters from a fibreboard production factory. The reactor is a hybrid USBF, combining an upflow anaerobic sludge blanket (UASB) in the lower part and an upflow anaerobic filter (UAF) at the top. PMID:12153033

Puñal, A; Roca, E; Lema, J M




EPA Science Inventory

The U.S. Environmental Protection Agency (USEPA) first issued detailed guidance on the design, construction, and operation of onsite wastewater treatment systems (OWTSs) in 1980. Design Manual: Onsite Wastewater Treatment and Disposal Systems (USEPA.1980) was the most comprehens...



EPA Science Inventory

Twenty-eight lime stabilization facilities were visited. None of these plants were originally designed for sludge lime stabilization. Lime stabilization was instituted either as a permanent sludge handling mechanism to replace a more costly process, as an interim sludge handling ...


Toxicity Tests for Ensuring Succesful Industrial Wastewater Treatment Plant Operation  

NASA Astrophysics Data System (ADS)

Industrial wastewaters are complex and can be polluted by non-biodegradable end toxic organic compounds and are a serious threat to the environment. Chemical procedure alone cannot provide sufficient information. A complete evaluation of wastewaters should include ecotoxicological tests too, especially concerning the complex wastewaters. In the literature review the authors attempted to establish which is the more promising and suitable aquatic toxicology test for sewage treatment plant influent toxicity monitoring. A variety of types of organisms representing different trophic levels and many different species are used for aquatic toxicity testing. Toxicity characterization would be needed both for influents and effluents of wastewater treatment plant. For the purpose of screening biological wastewater treatment influent, toxicity to activated sludge microorganisms is important and toxicology tests here used are respirometry and bioluminescence toxicology tests. Respirometry toxicity tests are easy, fast and inexpensive compared to other approaches. Bioluminescence has been widely used, the most thoroughly investigated test system is the Microtox. The toxicity tests have also been compared by different authors. International, national and regional authorities use these tools to meet various regulatory and legislative requirements. Importance of biotesting has been emphasized also in EU legislation.

C?bere, B.; Falti?a, E.; Zel??ns, N.; Kalni?a, D.



Impacts of Multiwalled Carbon Nanotubes on Nutrient Removal from Wastewater and Bacterial Community Structure in Activated Sludge  

PubMed Central

Background The increasing use of multiwalled carbon nanotubes (MWCNTs) will inevitably lead to the exposure of wastewater treatment facilities. However, knowledge of the impacts of MWCNTs on wastewater nutrient removal and bacterial community structure in the activated sludge process is sparse. Aims To investigate the effects of MWCNTs on wastewater nutrient removal, and bacterial community structure in activated sludge. Methods Three triplicate sequencing batch reactors (SBR) were exposed to wastewater which contained 0, 1, and 20 mg/L MWCNTs. MiSeq sequencing was used to investigate the bacterial community structures in activated sludge samples which were exposed to different concentrations of MWCNTs. Results Exposure to 1 and 20 mg/L MWCNTs had no acute (1 day) impact on nutrient removal from wastewater. After long-term (180 days) exposure to 1 mg/L MWCNTs, the average total nitrogen (TN) removal efficiency was not significantly affected. TN removal efficiency decreased from 84.0% to 71.9% after long-term effects of 20 mg/L MWCNTs. After long-term exposure to 1 and 20 mg/L MWCNTs, the total phosphorus removal efficiencies decreased from 96.8% to 52.3% and from 98.2% to 34.0% respectively. Further study revealed that long-term exposure to 20 mg/L MWCNTs inhibited activities of ammonia monooxygenase and nitrite oxidoreductase. Long-term exposure to 1 and 20 mg/L MWCNTs both inhibited activities of exopolyphosphatase and polyphosphate kinase. MiSeq sequencing data indicated that 20 mg/L MWCNTs significantly decreased the diversity of bacterial community in activated sludge. Long-term exposure to 1 and 20 mg/L MWCNTs differentially decreased the abundance of nitrifying bacteria, especially ammonia-oxidizing bacteria. The abundance of PAOs was decreased after long-term exposure to 20 mg/L MWCNTs. The abundance of glycogen accumulating organisms (GAOs) was increased after long-term exposure to 1 mg/L MWCNTs. Conclusion MWCNTs have adverse effects on biological wastewater nutrient removal, and altered the diversity and structure of bacterial community in activated sludge.

Hai, Reti; Wang, Yulin; Wang, Xiaohui; Du, Zhize; Li, Yuan



A Guide for Developing Standard Operating Job Procedures for the Digestion Process Wastewater Treatment Facility. SOJP No. 10.  

ERIC Educational Resources Information Center

This guide describes standard operating job procedures for the digestion process of wastewater treatment facilities. This process is for reducing the volume of sludge to be treated in subsequent units and to reduce the volatile content of sludge. The guide gives step-by-step instructions for pre-startup, startup, continuous operating, shutdown,…

Schwing, Carl M.


Operation and Maintenance of Wastewater Treatment Facilities.  

ERIC Educational Resources Information Center

Presents the 1978 literature review of wastewater treatment: (1) operators, training, and certification; (2) solutions to operating problems; (3) collection systems; (4) operations manuals; (5) wastewater treatment facility case histories; (5) land application; and (6) treatment of industrial wastes. A list of 36 references is also presented. (HM)

Drury, Douglas D.



Membrane Separation Bioreactors for Wastewater Treatment  

Microsoft Academic Search

With continuing depletion of fresh water resources, focus has shifted more toward water recovery, reuse, and recycling, which require an extension of conventional wastewater treatment technologies. Downstream external factors like stricter compliance requirements for wastewater discharge, rising treatment costs, and spatial constraints necessitate renewed investigation of alternative technologies. Coupled with biological treatment processes, membrane technology has gained considerable attention due

C. Visvanathan; R. Ben Aim; K. Parameshwaran



Simulation of wastewater treatment by aerobic granules in a sequencing batch reactor based on cellular automata.  


In the present paper, aerobic granules were developed in a sequencing batch reactor (SBR) using synthetic wastewater, and 81 % of granular rate was obtained after 15-day cultivation. Aerobic granules have a 96 % BOD removal to the wastewater, and the reactor harbors a mount of biomass including bacteria, fungi and protozoa. In view of the complexity of kinetic behaviors of sludge and biological mechanisms of the granular SBR, a cellular automata model was established to simulate the process of wastewater treatment. The results indicate that the model not only visualized the complex adsorption and degradation process of aerobic granules, but also well described the BOD removal of wastewater and microbial growth in the reactor. Thus, CA model is suitable for simulation of synthetic wastewater treatment. This is the first report about dynamical and visual simulation of treatment process of synthetic wastewater in a granular SBR. PMID:24696379

Benzhai, Hai; Lei, Liu; Ge, Qin; Yuwan, Peng; Ping, Li; Qingxiang, Yang; Hailei, Wang



Bioaugmentation to improve nitrification in activated sludge treatment.  


Bioaugmentation is a proposed technique to improve nutrient removal in municipal wastewater treatment. Compared with commonly used nitrification/denitrification (NDN) processes, bioaugmentation may be able to reduce tankage or land requirements. Many approaches for bioaugmentation have been developed, but few studies have compared the benefits among different approaches. This paper quantifies the effectiveness of bioaugmentation processes and investigates three major "onsite" bioaugmentation alternatives: 1) the parallel-plants approach, which uses acclimated biomass grown in a nitrifying "long-SRT" (sludge retention time) plant to augment a low-SRT treatment plant; 2) the enricher-reactor approach, which uses an offline reactor to produce the augmentation cultures; and 3) the enricher-reactor/return activated sludge (ER-RAS) approach, which grows enrichment culture in a reaeration reactor that receives a portion of the recycle activated sludge. Kinetic models were developed to simulate each approach, and the benefits of various approaches are presented on the same basis with controllable parameters, such as bioaugmentation levels, aeration tank volume, and temperatures. Examples were given to illustrate the potential benefits of bioaugmentation by upgrading a "carbon-only" wastewater treatment plant to nitrification. Simulation results suggested that all bioaugmentation approaches can decrease the minimum SRT for nitrification. The parallel-plants approach creates the highest concentration of biomass but may fail at too low temperature. The ER-RAS approach likely would be more useful at lower temperature and required less reactor volume; enricher-reactor approach would likely be more advantageous in the presence of inhibitory compound(s). PMID:20572460

Leu, Shao-Yuan; Stenstrom, Michael K



Study on the methylene blue adsorption from wastewaters by pore-expanded calcium fluoride sludge adsorbent.  


The adsorption of methylene blue (MB) onto pore-expanded calcium fluoride sludge (ECF) by the batch adsorption technique was investigated. The results showed that the adsorption capacity increased with increasing MB concentration but decreased as pH was increased. In order to investigate the adsorption mechanisms, three simplified isotherm models and kinetic models were used in this study. The best-fit adsorption isotherm was achieved with the Temkin model. Furthermore, the pseudo-second-order kinetic model agreed very well with the dynamical behavior for the adsorption of MB onto ECF. Thermodynamic studies revealed that the adsorption process of MB onto ECF was spontaneous and exothermic. The results indicated that ECF adsorbed MB efficiently and could be used as a waste adsorbent for the removal of cationic dyes in wastewater treatment. PMID:24734762

Hong, Junming; Lin, Bing; Hong, Gui-Bing; Chang, Chang-Tang



Recovering and recycling Hg from chlor-alkali plant wastewater sludge  

NASA Astrophysics Data System (ADS)

Montana Tech of the University of Montana and Universal Dynamics of British Columbia have developed a hydrometallurgical process for recovering and recycling mercury from chlorine plant wastewater sludge materials (U.S. Environmental Protection Agency [EPA]hazardous-waste classification K106). The hydrometallurgical process is also applicable for the treatment of mercury-contaminated soils (EPA hazardous waste classification D009) and other mercury-bearing waste materials. The process, which is capable of lowering the mercury content in the K106 solids from 10% to <50 mg/kg Hg, has been commercialized and utilized at three U.S. plants. This paper describes the fundamental chemistry of the process, the flowsheet being used, and operating plant case histories.

Twidwell, L. G.; Thompson, R. J.



Onsite Wastewater Treatment Systems: Aerobic Treatment Unit  

E-print Network

treatment process includes four main components that work together to purify wastewater: A pretreatment tank, generally ? referred to as the ?trash tank? because it removes materials that microorganisms (microbes) can- not degrade. An aeration chamber..., where ? aerobic microbes decompose waste in the water. An aeration system consists of an air pump, piping, and diffusers that force air into the aeration chamber. The air pump, located near the aerobic tank, compresses air to flow...

Lesikar, Bruce J.



Biological treatment of composition B wastewaters. 3. Analysis of performance of holston army ammunition plant wastewater treatment facility, January 1985 through August 1986: Errata. Technical report, January 1986-December 1987  

SciTech Connect

Effluent biochemical oxygen demand (BOD) levels at the Holston Army Ammunition Plant wastewater treatment facility, as quoted in US Army Biomedical Research and Development Laboratory Technical Report 8806, are in error. This report corrects those values, as we as the derived rate coefficients for BOD destruction. Conclusions from the earlier report are unchanged.... Composition B, Explosives, Wastewater, Anoxic filter, Activated sludge RDX.

Burrows, W.D.; Paulson, E.T.; Carnahan, R.P.



Dissolved oxygen control of mechanical aerators at the Rensselaer county wastewater treatment plant. Final report  

Microsoft Academic Search

The report describes the results of testing dissolved oxygen analyzers to control operation of mechanical aerators at the Rensselaer County Sewer District Wastewater Treatment Plant and reduce the amount of energy uses while maintaining or enhancing biological treatment. Current electricity costs are more than $300,000 annually for aeration in the activated sludge process. Motors for the aerators are manually controlled

F. J. Wurtenberger; W. K. Biski; J. A. Guagno



A Guide to the Selection of Cost-Effective Wastewater Treatment Systems. Technical Report.  

ERIC Educational Resources Information Center

The data within this publication provide guidelines for planners, engineers and decision-makers at all governmental levels to evaluate cost-effectiveness of alternative wastewater treatment proposals. The processes described include conventional and advanced treatment units as well as most sludge handling and processing units. Flow sheets, cost…

Van Note, Robert H.; And Others


Identifying energy and carbon footprint optimization potentials of a sludge treatment line with Life Cycle Assessment.  


This study exemplifies the use of Life Cycle Assessment (LCA) as a tool to quantify the environmental impacts of processes for wastewater treatment. In a case study, the sludge treatment line of a large wastewater treatment plant (WWTP) is analysed in terms of cumulative energy demand and the emission of greenhouse gases (carbon footprint). Sludge treatment consists of anaerobic digestion, dewatering, drying, and disposal of stabilized sludge in mono- or co-incineration in power plants or cement kilns. All relevant forms of energy demand (electricity, heat, chemicals, fossil fuels, transport) and greenhouse gas emissions (fossil CO(2), CH(4), N(2)O) are accounted in the assessment, including the treatment of return liquor from dewatering in the WWTP. Results show that the existing process is positive in energy balance (-162 MJ/PE(COD) * a) and carbon footprint (-11.6 kg CO(2)-eq/PE(COD) * a) by supplying secondary products such as electricity from biogas production or mono-incineration and substituting fossil fuels in co-incineration. However, disposal routes for stabilized sludge differ considerably in their energy and greenhouse gas profiles. In total, LCA proves to be a suitable tool to support future investment decisions with information of environmental relevance on the impact of wastewater treatment, but also urban water systems in general. PMID:23128622

Remy, C; Lesjean, B; Waschnewski, J



Disinfection of wastewater from a Riyadh Wastewater Treatment Plant with ionizing radiation  

NASA Astrophysics Data System (ADS)

The goal of this research was to establish the applicability of the electron beam treatment process for treating wastewater intended for reuse. The objective of this study was to determine the effectiveness of gamma irradiation in the disinfection of wastewater, and the improvement of the water quality by determining the changes in organic matter as indicated by the measurement of biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total organic carbon (TOC). Samples of effluent, before and after chlorination, and sludge were obtained from a Riyadh Wastewater Treatment Plant. The studies were conducted using a laboratory scale 60Co gamma source. The improvement in quality of the irradiated samples was demonstrated by the reduction in bacteria, and the reduction in the BOD, COD and TOC. Radiation of the wastewater provided adequate disinfection while at the same time increasing the water quality. This treatment could lead to additional opportunities for the reuse of this valuable resource. Limited studies, conducted on the anaerobically digested secondary biosolids, showed an improvement in bacterial content and no change in COD.

Basfar, A. A.; Abdel Rehim, F.



Quorum quenching is responsible for the underestimated quorum sensing effects in biological wastewater treatment reactors.  


Quorum sensing (QS) and quorum quenching (QQ) are two antagonistic processes coexisting in various bacterial communities in bioreactors, e.g., activated sludge for biological wastewater treatment. Although QS signal molecules are detected in activated sludge reactors and known to affect sludge properties and reactor performance, there has been no direct evidence to prove the endogenous existence of QQ effects in activated sludge. In this study, for the first time, acyl homoserine lactones-degrading enzymatic activity, a typical QQ effect, was discovered in activated sludge and found to considerably affect the QS detection results. The coexistence of QS and QQ bacteria in activated sludge was further confirmed by bacterial screening and denaturing gradient gel electrophoresis analysis. The method developed in this study could also be used to evaluate QQ activities in bioreactors, and a possible way is provided to tune bioreactor performance through balancing the QS and QQ processes. PMID:25182424

Song, Xiang-Ning; Cheng, Yuan-Yuan; Li, Wen-Wei; Li, Bing-Bing; Sheng, Guo-Ping; Fang, Cai-Yun; Wang, Yun-Kun; Li, Xiao-Yan; Yu, Han-Qing



Feasibility study to upgrade a textile wastewater treatment plant by a hollow fibre membrane bioreactor for effluent reuse  

Microsoft Academic Search

A pilot plant membrane bioreactor has been tested in parallel with a full-scale activated sludge wastewater treatment plant fed on the wastewater from a textile factory. The possibility to upgrade the final effluent for internal reuse was investigated. The pilot and full-scale plants are located in a textile factory (Boselli & C., Olgiate Comasco, North Italy) which manufactures and finishes

F. Malpei; L. Bonomo; A. Rozzi



Comparative anaerobic treatment of wastewater from pharmaceutical, brewery, paper and amino acid producing industries.  


This study concerned the anaerobic treatment of five different industrial wastewaters with a diverse and complex chemical composition. The kinetics of biotransformation of this wastewater at different chemical oxygen demand (COD) were studied in a batch reactor. Wastewater from an amino acid producing industry (Fermex) and from a tank that received several types of wastewaters (collector) contained 0.83 g l(-1) and 0.085 g l(-1) sulfate, respectively. During the study period of 20 days, methane formation was observed in all types of wastewaters. Studies on COD biodegradation showed the reaction velocity was higher for Fermex wastewater and lower for collector wastewater, with values of 0.0022 h(-1) and 0.0011 h(-1), respectively. A lower methanogenic activity of 0.163 g CH4 day(-1) g(-1) volatile suspended solids (VSS) and 0.20 g CH4 day(-1) g(-1) VSS, respectively, was observed for paper producing and brewery wastewater. Adapted granular sludge showed the best biodegradation of COD during the 20-day period. The sulfate-reducing activity in pharmaceutical and collector wastewater was studied. A positive effect of sulfate-reducing activity on methanogenic activity was noted for both types of wastewaters, both of which contained sulfate ions. All reactions of methane generation for the tested industrial wastewaters were first-order. The results of this study suggest that the tested wastewaters are amenable to anaerobic treatment. PMID:15937696

Rodríguez-Martínez, Jesús; Martínez-Amador, Silvia Y; Garza-García, Yolanda



Fenton process for treatment of desizing wastewater  

Microsoft Academic Search

Treatment of simulated desizing wastewater by the Fenton process along with chemical coagulation was investigated. The simulated wastewater contained less than 0.2% polyvinyl alcohol (PVA) and Blue G (a direct dye) or Black B (a reactive dye). Experiments were conducted to investigate the effects of operating variables, including pH, temperature and the treatment time, on the COD removal efficiency. Optimal

Sheng H. Lin; Cho C. Lo



K Basin sludge treatment process description  

SciTech Connect

The K East (KE) and K West (KW) fuel storage basins at the 100 K Area of the Hanford Site contain sludge on the floor, in pits, and inside fuel storage canisters. The major sources of the sludge are corrosion of the fuel elements and steel structures in the basin, sand intrusion from outside the buildings, and degradation of the structural concrete that forms the basins. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be treated so that it meets Tank Waste Remediation System (TWRS) acceptance criteria and can be sent to one of the double-shell waste tanks. The US Department of Energy, Richland Operations Office accepted a recommendation by Fluor Daniel Hanford, Inc., to chemically treat the sludge. Sludge treatment will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and reacting the solution with caustic to co-precipitate the uranium and plutonium. A truck will transport the resulting slurry to an underground storage tank (most likely tank 241-AW-105). The undissolved solids will be treated to reduce the transuranic (TRU) and content, stabilized in grout, and transferred to the Environmental Restoration Disposal Facility (ERDF) for disposal. This document describes a process for dissolving the sludge to produce waste streams that meet the TWRS acceptance criteria for disposal to an underground waste tank and the ERDF acceptance criteria for disposal of solid waste. The process described is based on a series of engineering studies and laboratory tests outlined in the testing strategy document (Flament 1998).

Westra, A.G.




EPA Science Inventory

Petroleum API Separator sludge was applied to field plots to evaluate optimization of loading rates and frequencies for waste disposal by land treatment. Loading rates 3 to 13 weight percent and frequencies 1 to 12, respectively, per year were studied over an 18 month period. Tot...


Proof of concept for a new energy-positive wastewater treatment scheme.  


For improved exploitation of the energy content present in the organic matter of raw sewage, an innovative concept for treatment of municipal wastewater is tested in pilot trials and assessed in energy balance and operational costs. The concept is based on a maximum extraction of organic matter into the sludge via coagulation, flocculation and microsieving (100 ?m mesh size) to increase the energy recovery in anaerobic sludge digestion and decrease aeration demand for carbon mineralisation. Pilot trials with real wastewater yield an extraction of 70-80% of total chemical oxygen demand into the sludge while dosing 15-20 mg/L Al and 5-7 mg/L polymer with stable operation of the microsieve and effluent limits below 2-3 mg/L total phosphorus. Anaerobic digestion of the microsieve sludge results in high biogas yields of 600 NL/kg organic dry matter input (oDMin) compared to 430 NL/kg oDMin for mixed sludge from a conventional activated sludge process. The overall energy balance for a 100,000 population equivalent (PE) treatment plant (including biofilter for post-treatment with full nitrification and denitrification with external carbon source) shows that the new concept is an energy-positive treatment process with comparable effluent quality than conventional processes, even when including energy demand for chemicals production. Estimated operating costs for electricity and chemicals are in the same range for conventional activated sludge processes and the new concept. PMID:25429462

Remy, C; Boulestreau, M; Lesjean, B




EPA Science Inventory

The paper presents preliminary results from a U.S. EPA test program on municipal wastewater sludge incinerators. The major objectives of the program were the following: (1) collecting data that allow a comparison of metals and organic compound emissions during steady-state and tr...


Reuse of activated sludge biomass: I. Removal of basic dyes from wastewater by biomass  

Microsoft Academic Search

The removal of basic dyes from wastewater was studied using activated sludge biomass as an adsorbent. The experimental results of COD removal (%) showed that for various basic dyes, adsorption by biomass was not only feasible but also effective. The kinetics of adsorption followed first-order processes, controlled by film diffusion. Influences on adsorption capacity of various factors, such as chemical

H. C Chu; K. M Chen




EPA Science Inventory

Emissions of metals and organics from a series of four wastewater sludge incinerators were determined. hree multiple hearth units and one fluidized bed combustor were tested. missions were controlled with a combination of venturi and/or tray impingement scrubbers. ne site incorpo...


On-Site Wastewater Treatment Systems: Graywater  

E-print Network

-6176 3-08 Figure 1: A diagram of separate blackwater and graywater plumbing systems. W ith water reuse gaining popularity, people increasingly consider graywater from their residences as a resource to be separated from the wastewater stream... and reused in their landscapes. Such reuse of graywater reduces the amount of wastewater entering sewers or onsite wastewater treatment systems, reduces demands to use potable water for other residential uses like irrigation and helps preserve limited...

Melton, Rebecca; Lesikar, Bruce J.; Smith, David; O'Neill, Courtney




EPA Science Inventory

Zenon Environmental System's ZenoGem? Wastewater Treatment Process treats aqueous media contaminated with volatile/semi-volatile organic compounds. This technology combines aerobic biological treatment to remove biodegradable organic compounds with ultrafiltration to separate res...


Recent advances in membrane bio-technologies for sludge reduction and treatment.  


This paper is designed to critically review the recent developments of membrane bio-technologies for sludge reduction and treatment by covering process fundamentals, performances (sludge reduction efficiency, membrane fouling, pollutant removal, etc.) and key operational parameters. The future perspectives of the hybrid membrane processes for sludge reduction and treatment are also discussed. For sludge reduction using membrane bioreactors (MBRs), literature review shows that biological maintenance metabolism, predation on bacteria, and uncoupling metabolism through using oxic-settling-anaerobic (OSA) process are promising ways that can be employed in full-scale applications. Development of control methods for worm proliferation is in great need of, and a good sludge reduction and MBR performance can be expected if worm growth is properly controlled. For lysis-cryptic sludge reduction method, improvement of oxidant dispersion and increase of the interaction with sludge cells can enhance the lysis efficiency. Green uncoupler development might be another research direction for uncoupling metabolism in MBRs. Aerobic hybrid membrane system can perform well for sludge thickening and digestion in small- and medium-sized wastewater treatment plants (WWTPs), and pilot-scale/full-scale applications have been reported. Anaerobic membrane digestion (AMD) process is a very competitive technology for sludge stabilization and digestion. Use of biogas recirculation for fouling control can be a powerful way to decrease the energy requirements for AMD process. Future research efforts should be dedicated to membrane preparation for high biomass applications, process optimization, and pilot-scale/full-scale tracking research in order to push forward the real and wide applications of the hybrid membrane systems for sludge minimization and treatment. PMID:23466365

Wang, Zhiwei; Yu, Hongguang; Ma, Jinxing; Zheng, Xiang; Wu, Zhichao



Nanomaterial transformation and association with fresh and freeze-dried wastewater activated sludge: implications for testing protocol and environmental fate.  


Engineered nanomaterials (ENMs) are an emerging class of contaminants entering wastewater treatment plants (WWTPs), and standardized testing protocols are needed by industry and regulators to assess the potential removal of ENMs during wastewater treatment. A United States Environmental Protection Agency (USEPA) standard method (OPPTS 835.1110) for estimating soluble pollutant removal during wastewater treatment using freeze-dried, heat-treated (FDH) activated sludge (AS) has been recently proposed for predicting ENM fate in WWTPs. This study is the first to evaluate the use of FDH AS in batch experiments for quantifying ENM removal from wastewater. While soluble pollutants sorbed equally to fresh and FDH AS, fullerene, silver, gold, and polystyrene nanoparticles' removals with FDH AS were approximately 60-100% less than their removals with fresh AS. Unlike fresh AS, FDH AS had a high concentration of proteins and other soluble organics in the liquid phase, an indication of bacterial membrane disintegration due to freeze-drying and heat exposure. This cellular matter stabilized ENMs such that they were poorly removed by FDH AS. Therefore, FDH AS is not a suitable sorbent for estimating nanoparticle removal in WWTPs, whereas fresh AS has been shown to reasonably predict full-scale performance for titanium removal. This study indicates that natural or engineered processes (e.g., anaerobic digestion, biosolids decomposition in soils) that result in cellular degradation and matrices rich in surfactant-like materials (natural organic matter, proteins, phospholipids, etc.) may transform nanoparticle surfaces and significantly alter their fate in the environment. PMID:22320890

Kiser, Mehlika A; Ladner, David A; Hristovski, Kiril D; Westerhoff, Paul K



The use of the anaerobic baffled reactor (ABR) for wastewater treatment: a review  

Microsoft Academic Search

A review concerning the development, applicability and possible future application of the anaerobic baffled reactor for wastewater treatment is presented. The reactor design has been developed since the early 1980s and has several advantages over well established systems such as the upflow anaerobic sludge blanket and the anaerobic filter. These include: better resilience to hydraulic and organic shock loadings, longer

William P. Barber; David C. Stuckey



Primary Treatment and Sludge Digestion Workshop.  

ERIC Educational Resources Information Center

This manual was developed for use at workshops designed to upgrade the knowledge of experienced wastewater treatment plant operators. Each of the sixteen lessons has clearly stated behavioral objectives to tell the trainee what he should know or do after completing that topic. Areas covered in this manual include: sewage characteristics;…

Ontario Ministry of the Environment, Toronto.


[Biological wastewater treatment and simultaneous generating electricity from organic wastewater by microbial fuel cell].  


An air-cathode microbial fuel cell (ACMFC) was successfully started up using anaerobic activated sludge as inoculums, generating a voltage of 0.24V after inoculations for 110 h. When using acetate and glucose as substrate, voltage of 0.38V and 0.41V (based on external resistance of 1000 omega) is obtained; meanwhile, the maximum power density reaches 146.56 mW/m2 and 192.04 mW/m2 respectively, suggesting that organic wastewater can be used to produce electricity. Removal efficiency of 99% (acetate) and 87% (glucose) is achieved simultaneously, demonstrating that ACMFC can treat organic wastewater. Electron recovery efficiency as low as 10% for both acetate and glucose is observed mainly due to aerobic respiration of microorganisms caused by diffusion of oxygen molecular from the cathode, leading to electron loss. MFCs are capable of converting chemical energy presented in organic wastewater into electricity energy with accomplishments of wastewater treatments simultaneously, which possibly captures considerable benefits in terms of environments and economics. PMID:17117633

You, Shi-jie; Zhao, Qing-liang; Jiang, Jun-qiu



Application of Ozone in Textile Wastewater Treatment  

Microsoft Academic Search

Textile wastewaters are known to be highly resistant to biodegradation under both natural and wastewater treatment plant conditions. However, ozonation can be used to increase the biodegradability of the biologically resistant compounds. The combined method of ozonation and subsequent biodegradation of both synthetic and real textile wastes was explored in laboratory-scale studies. Two kinds of industrial wastes were simulated for

Jan Perkowski; Lech Kos; Stanisaw Ledakowicz



When Research Turns to Sludge  

ERIC Educational Resources Information Center

Sewage sludge is composed of residuals removed from wastewater that comes from homes, hospitals, and industries. Wastewater-treatment systems are designed to remove pollutants that could contaminate public waterways. Sludge--called "biosolids" by those who produce it, spread it, and regulate it--includes these pollutants as well as bacteria and…

Wing, Steve



Treatment of brewery wastewater using anaerobic sequencing batch reactor (ASBR).  


Brewery wastewater was treated in a pilot-scale anaerobic sequencing batch reactor (ASBR) in which a floating cover(@) was employed. Long time experiments showed that the reactor worked stably and effectively for COD removal and gas production. When the organic loading rate was controlled between 1.5 kg COD/m3 d and 5.0 kg COD/m(3)d, and hydraulic retention time one day, COD removal efficiency could reach more than 90%. Sludge granulation was achieved in the reactor in approximately 60 days, which is much less than the granulation time ever reported. In addition, high specific methanogenic activity (SMA) for formate was observed. The study suggests that the ASBR technology is a potential alternative for brewery wastewater treatment. PMID:17659870

Shao, Xiangwen; Peng, Dangcong; Teng, Zhaohua; Ju, Xinghua



Environmental Degradations by Microorganisms at Low Temperatures. Wastewater Treatment,  

National Technical Information Service (NTIS)

The paper describes the attempts of using specially selected bacterial sludges for low-temperature removal of organic and nitrogen components in wastewater. Each step, carbon oxidation, nitrification and denitrification was studied in detail and various c...

G. Halmo




EPA Science Inventory

Pathogens can enter municipal wastewaters from several sources including homes, hospitals and slaughter houses. They are identified, typical levels found in sludges are given along with infectious doses, and their survival on crops and in the soil presented. As wastewater is clea...


Sludge minimization using aerobic/anoxic treatment technology  

SciTech Connect

The objective of this investigation was to demonstrate through a bench-scale study that using an aerobic/anoxic sequence to treat wastewater and biosolids could significantly reduce the production of biosolids (sludge). A bench-scale activated sludge reactor and anoxic digester were operated for approximately three months. The process train consisted of a completely-mixed aerobic reactor with wasting of biosolids to an anoxic digester for stabilization. The system was operated such that biomass produced in the aerobic activated sludge process was wasted to the anoxic digester; and biomass produced in the anoxic digester was wasted back to the activated sludge process. A synthetic wastewater consisting of bacto-peptone nutrient broth was fed to the liquid process train. Influent and effluent to the aerobic biological process train were analytically tested, as were the contents of mixed liquor in the aerobic reactor and anoxic digester. Overall removal efficiencies for the activated sludge process with regard to COD, TKN, NH{sub 3}-N, and alkalinity averaged 91, 89, 98, and 38%, respectively. The overall average sludge production for the aerobic/anoxic process was 24% less than the overall average sludge production from a conventional activated sludge bench-scale system fed the same substrate and operated under similar mean cell residence times.

Mines, R.O. Jr.; Kalch, R.S.



Biological treatment of TMAH (tetra-methyl ammonium hydroxide) in a full-scale TFT-LCD wastewater treatment plant.  


This study evaluated biological treatment of TMAH in a full-scale methanogenic up-flow anaerobic sludge blanket (UASB) followed by an aerobic bioreactor. In general, the UASB was able to perform a satisfactory TMAH degradation efficiency, but the effluent COD of the aerobic bioreactor seemed to increase with an increased TMAH in the influent wastewater. The batch test results confirmed that the UASB sludge under methanogenic conditions would be favored over the aerobic ones for TMAH treatment due to its superb ability of handling high strength of TMAH-containing wastewaters. Based on batch experiments, inhibitory chemicals present in TFT-LCD wastewater like surfactants and sulfate should be avoided to secure a stable methanogenic TMAH degradation. Finally, molecular monitoring of Methanomethylovorans hollandica and Methanosarcina mazei in the full-scale plant, the dominant methanogens in the UASB responsible for TMAH degradation, may be beneficial for a stable TMAH treatment performance. PMID:22456234

Hu, Tai-Ho; Whang, Liang-Ming; Liu, Pao-Wen Grace; Hung, Yu-Ching; Chen, Hung-Wei; Lin, Li-Bin; Chen, Chia-Fu; Chen, Sheng-Kun; Hsu, Shu Fu; Shen, Wason; Fu, Ryan; Hsu, Romel



Process for biological wastewater treatment  

Microsoft Academic Search

For the biological purification of wastewater in a reactor in the presence of open-pore and compressible carrier material for biomass, the carrier material, prior to its use in the reactor, is loaded with bacteria, finely divided, inorganic and\\/or organic compounds, selected for wastewater purification, and is then either stored or used in the process, the loaded carrier being especially useful

A. Frydman; H. Reimann



Treatment of HMX-production wastewater in an aerobic granular reactor.  


Aerobic granules were applied to the treatment of HMX-production wastewater using a gradual domestication method in a SBR. During the process, the granules showed a good settling ability, a high biomass retention rate, and high biological activity. After 40 days of stable operation, aerobic granular sludge performed very effectively in the removal of carbon and nitrogen compounds from HMX-production wastewater. Organic matter removal rates up to 97.57% and nitrogen removal efficiencies up to 80% were achieved during the process. Researchers conclude that using aerobic granules to treat explosive wastewater has good prospects for success. PMID:23697233

Zhang, Jin-Hua; Wang, Min-Hui; Zhu, Xiao-Meng



Treatment of desizing wastewater by catalytic thermal treatment and coagulation.  


In the present study, the coagulation of the fresh and thermally treated desizing wastewater has been reported. The maximum COD reduction of fresh desizing wastewater using coagulation was observed with commercial alum at initial pH 4. This was followed by aluminum potassium sulfate (pH 4), FeCl(3) (pH 6), PAC (pH 6) and FeSO(4) (pH 4). The maximum COD reduction observed at a coagulant (commercial alum) dose of 5 kg/m(3) and pH 4 was 58% whereas the color reduction at these conditions was 85%. The results reveal that the application of coagulation on the catalytic thermal treated effluent is more effective in removing nearly 88% of COD and 96% of color at above mentioned conditions except at a coagulant dose of 1 kg/m(3). The amount of inorganic sludge generated gets drastically reduced (almost 25%) due to the reduced amount of coagulant. The COD and color of the final effluent were found to be 98.6 mg/l and 2.67 PCU, respectively, and the COD/BOD(3) ratio was 1.36. The settling rate of the slurry was found to be strongly influenced by treatment pH. The slurry obtained after treatment at pH 12 settled faster in comparison to slurry obtained at pH 4. The filterability of the treated effluent is also strongly dependent on pH. pH 12 was adjudged to be the best in giving highest filtration rate. PMID:18687524

Kumar, Pradeep; Prasad, B; Chand, Shri



Water/Wastewater Treatment Plant Operator Qualifications.  

ERIC Educational Resources Information Center

This article summarizes in tabular form the U.S. and Canadian programs for classification of water and wastewater treatment plant personnel. Included are main characteristics of the programs, educational and experience requirements, and indications of requirement substitutions. (CS)

Water and Sewage Works, 1979




EPA Science Inventory

Rapid infiltration treatment performance of three infiltration basins receiving primary treated municipal wastewater is evaluated for optimum total nitrogen control using a series of manual operational techniques and by remote control computer operation of a sprinkler system. Thr...



EPA Science Inventory

The purpose of this publication is to discuss typical design parameters for the unit processes involved in physical-chemical treatment of raw wastes, and how the design engineer may determine the design criteria best suited for a given wastewater....



EPA Science Inventory

A revision to the 1971 original, it discusses and evaluates corrective actions that are required to upgrade existing municipal wastewater treatment plants. ull chapter is devoted to case histories of successful upgrading situations....


Onsite Wastewater Treatment Systems: Operation and Maintenance  

E-print Network

Soil absorption fieldTwo-compartment septic tank Perforated pipe for effluent disposal Sand/loam soil Gravel Geotextile fabric Onsite wastewater treatment systems Operation and maintenance L-5347 8-08 Figure 1: A septic tank and soil absorption... field system. I f your home or business uses an onsite wastewater treatment system, common- ly known as a septic system, you need to know how to operate and maintain the system properly to prevent pollution and sewage backups. For many years, people...

Lesikar, Bruce J.




EPA Science Inventory

The most widely used method of wastewater treatment is biological treatment. The use of kinetic models to describe the behavior of a biological wastewater treatment process has become widely accepted practice. The most often used kinetic models include those developed by Eckenfel...


Onsite Wastewater Treatment Systems: Understanding and Maintaining your Septic System  

E-print Network

Understanding and maintaining your septic system L-5491 9-08 Figure 1: Components of an on-site wastewater treatment system. Onsite wastewater treatment systems Well 1. Wastewater source 2. Collection and storage 3. Pretreatment Groundwater 4.... Final treatment and dispersal P roper operation and maintenance of your wastewater treatment system is critical for its performance. Taking proper care of your system also: components; and final treatment and dispersal components. Wastewater source...

Lesikar, Bruce J.; Mechell, Justin; Alexander, Rachel



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


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. Surveys were conducted in central wastewater treatment plant in two industrial zones in Thailand. Samples were collected from influent, aeration tank, secondary clarifier effluent, effluent and sludge. The major purpose of this field study was to identify PFCs occurrences and mass flow during industrial WWTP. Solid-phase extraction (SPE) coupled with HPLC-ESI-MS/MS were used for the analysis. Total 10 PFCs including perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluoropropanoic acid (PFPA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorohexane sulfonate (PFHxS), perfluoronanoic acid (PFNA), perfluordecanoic acid (PFDA), perfluoroundecanoic acid (PFUnA), and perfluorododecanoic acid (PFDoA) were measured to identify their occurrences. PFCs were detected in both liquid and solid phase in most samples. The exceptionally high level of PFCs was detected in the treatment plant of IZ1 and IZ2 ranging between 662-847ngL(-1) and 674-1383ngL(-1), respectively, which greater than PFCs found in most domestic wastewater. Due to PFCs non-biodegradable property, both WWTPs were found ineffective in removing PFCs using activated sludge processes. Bio-accumulation in sludge could be the major removal mechanism of PFCs in the process. The increasing amount of PFCs after activated sludge processes were identified which could be due to the degradation of PFCs precursors. PFCs concentration found in the effluent were very high comparing to those in river water of the area. Industrial activity could be the one of major sources of PFCs contamination in the water environment. PMID:21439605

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



ENVIRONMENTAL BIOTECHNOLOGY Brewery wastewater treatment using air-cathode  

E-print Network

using actual wastewaters. The efficiency of wastewater treatment of a beer brewery wastewater. Keywords Microbial fuel cell . Beer brewery wastewater. Temperature . Solution conductivity Introduction The annual wastewater production from beer breweries in China is about 0.3 billion m3 , which is 1.5% to 2


Carbon footprint of four different wastewater treatment scenarios  

NASA Astrophysics Data System (ADS)

Since the era of industrialization, concentrations of greenhouse gases (GHGs) have tremendously increased in the atmosphere, as a result of the extensive use of fossil fuels, deforestation, improper waste management, transport, and other economic activities (Boer, 2008).This has led to a great accumulation of greenhouse gases, forming a blanket around the Earth which contributes in the so-called "Global Warming". Over the last decades, wastewater treatment has developed strongly and has become a very important asset in mitigating the impact of domestic and industrial effluents on the environment. There are many different forms of wastewater treatment, and one of the most effective treatment technology in terms COD, N and P removal, activated sludge is often criticized for its high energy use. Some other treatment concepts have a more "green" image, but it is not clear whether this image is justified based on their greenhouse gas emission. This study focuses on the estimation of GHG emissions of four different wastewater treatment configurations, both conventional and innovative systems namely: (1) Harnaschpolder, (2) Sneek, (3) EIER-Ouaga and (4) Siddhipur. This analysis is based on COD mass balance, the Intergovernmental Panel on Climate Change (IPCC) 2006 guidelines for estimating CO2 and CH4, and literature review. Furthermore, the energy requirements for each of the systems were estimated based on energy survey. The study showed that an estimated daily average of 87 g of CO2 equivalent, ranging between 38 to 192 g, was derived to be the per capita CO2 emission for the four different wastewater treatment scenarios. Despite the fact that no electrical energy is used in the treatment process, the GHG emission from EIER Ouaga anaerobic pond systems is found to be the highest compared to the three other scenarios analysed. It was estimated 80% higher than the most favourable scenario (Sneek). Moreover, the results indicate that the GHGs emitted from these WWTPs are 97% lower compared to other anthropogenic sources like the public transport sector. The innovative sanitation scenarios were found to cause less environmental burden in terms of energy and GHGs. Nevertheless, to ensure a positive impact of these treatment systems, an optimum biogas reuse (for the production of electricity and heat), the source separation of human excreta (to disburden the wastewater treatment processes) should be introduced to reduce their GHG emissions. Keywords: Carbon dioxide, greenhouse gases, methane, wastewater treatment technologies.

Diafarou, Moumouni; Mariska, Ronteltap, ,, Dr.; Damir, Brdjanovic, ,, Prof.



Treatment and Disposal of Unanticipated 'Scavenger' Wastewater  

SciTech Connect

The Savannah River Site often generates wastewater for disposal that is not included as a source to one of the site's wastewater treatment facilities that are permitted by the South Carolina Department of Health and Environmental Control. The techniques used by the SRS contract operator (Westinghouse Savannah River Company) to evaluate and treat this unanticipated 'scavenger' wastewater may benefit industries and municipalities who experience similar needs. Regulations require that scavenger wastewater be treated and not just diluted. Each of the pollutants that are present must meet effluent permit limitations and/or receiving stream water quality standards. if a scavenger wastewater is classified as 'hazardous' under the Resource Conservation and Recovery Act (RCRA) its disposal must comply with RCRA regulations. Westinghouse Savannah River Company obtained approval from SCDHEC to dispose of scavenger wastewater under specific conditions that are included within the SRS National Pollutant Discharge Elimination System permit. Scavenger wastewater is analyzed in a laboratory to determine its constituency. Pollutant values are entered into spreadsheets that calculate treatment plant removal capabilities and instream concentrations. Disposal rates are computed, ensuring compliance with regulatory requirements and protection of treatment system operating units. Appropriate records are maintained in the event of an audit.

Payne, W.L.



Effects of seed sludge properties and selective biomass discharge on aerobic sludge granulation  

Microsoft Academic Search

This study was carried out to investigate the effects of seed sludge properties and the selective sludge discharge method on aerobic granulation in biological wastewater treatment. Small-loose flocs and larger-denser flocs were separated from raw activated sludge by sedimentation in a settling column. The two types of sludge were used as seed biomass in two laboratory batch reactors for the

Guo-ping Sheng; An-jie Li; Xiao-yan Li; Han-qing Yu



Wastewater treatment: Dye and pigment industry. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning treatment of wastewater containing dyes and pigments. The citations discuss the of dyes and pigments in wastewater treatment systems, biodegradation of dyes, absorption and adsorption processes to remove dyes from wastewater, environmental effects from the disposal of dye-containing wastes, and methods of analysis for dyes in waste streams. Treatment methods such as ozonation, reverse osmosis, activated charcoal filtration, activated sludge, electrochemical treatments, thermal treatments, simple filtration, and absorption media are included. (Contains a minimum of 112 citations and includes a subject term index and title list.)

Not Available



Treatment of Wood Preserving Wastewater  

E-print Network

The wastewater produced by the wood preserving industry presents a difficult problem to treat economically. A review of the literature indicates the size of the industry has limited the pursuit of an orderly and economic solution. Atmospheric...

Reynolds, T. D.; Shack, P. A.


Effect of plant species on water quality at the outlet of a sludge treatment wetland.  


Sludge treatment wetlands are mainly used to reduce the volume of activated sludge, and the pollutants at the outlet are generally returned to the wastewater treatment plant. However, in cases where sludges are produced far from treatment plants not only must the sludge be treated, but the discharge of pollutants into the surrounding environment must also be limited. The aim of this study was to evaluate the efficiency of different plant species in optimising pollutant removal in a decentralised sludge treatment wetland. In addition, a new system design was assessed, in which the wetland was not completely drained, and a saturated layer was created using an overflow. The experimental setup consisted of 16 mesocosms in total, planted with monocultures of Phragmites australis, Typha angustifolia and Scirpus fluviatilis, and unplanted controls, each in four replicates. The experiment was conducted during the third summer of operation after setup. The system was fed with highly concentrated fish farm sludge at a load of 30 kg of total solids m(-2) yr(-1). Results showed that such wetlands were highly efficient, with removal rates between 94% and 99% for most pollutants. Planted systems generally outperformed the unplanted control, with a significantly lower mass of pollutants at the outlet of the sludge treatment wetland planted with Phragmites, followed by those with Typha and then Scirpus. The distinct influence of plant species on pollution removal was explained by the sequestration of nitrogen and phosphorus in plant tissues and by the rhizosphere effect, which enhance the biodegradation of organic matter, allowed the nitrification process and created redox conditions favourable to the sorption of phosphorus. Filtration and evapotranspiration rates played a major role in limiting the discharge of pollutants, and the impact was enhanced by the fact that the sludge treatment wetland was not completely drained. PMID:22828383

Gagnon, Vincent; Chazarenc, Florent; Kõiv, Margit; Brisson, Jacques



Coke dust enhances coke plant wastewater treatment.  


Coke plant wastewater contain many toxic pollutants. Despite physico-chemical and biological treatment this specific type of wastewater has a significant impact on environment and human health. This article presents results of research on industrial adsorptive coke plant wastewater treatment. As a sorbent the coke dust, dozen times less expensive than pulverized activated carbon, was used. Treatment was conducted in three scenarios: adsorptive after full treatment with coke dust at 15gL(-1), biological treatment enhanced with coke dust at 0.3-0.5gL(-1) and addition of coke dust at 0.3gL(-1) prior to the biological treatment. The enhanced biological treatment proved the most effective. It allowed additional removal of 147-178mgCODkg(-1) of coke dust. PMID:25113994

Burmistrz, Piotr; Rozwadowski, Andrzej; Burmistrz, Micha?; Karcz, Aleksander



Conditioning of wastewater sludge using freezing and thawing: role of curing.  


Freeze/thaw (F/T) treatment is an efficient pre-treatment process for biological sludges. When bulk sludge was frozen, tiny unfrozen regimes in the ice matrix were continuously dehydrated by surrounding ice fronts, termed as the "curing stage". This work demonstrated that the F/T treatment could not only enhance sludge dewaterability, but also solubilize organic matters from sludge matrix. Most enhancement of sludge dewaterability was achieved during bulk freezing stage, with the waste activated sludge more readily dewatered than the mixed sludges after treatment. Conversely, the freezing stage released only limited quantities of organic matters to liquid. Conversely, the curing contributed mostly on chemical oxygen demand (COD) solubilization and NH(3)-N release. The crystallization of intra-aggregate moisture was claimed to damage cell membranes so to release intracellular substances to surroundings. The F/T treatment with sufficient curing is advised to effectively condition biological sludge as the feedstock of the following anaerobic digestion process. PMID:21925694

Hu, Kai; Jiang, Jun-Qiu; Zhao, Qing-Liang; Lee, Duu-Jong; Wang, Kun; Qiu, Wei



Immersed membrane activated sludge for the reuse of municipal wastewater  

Microsoft Academic Search

The results of two pilot studies of an immersed membrane activated sludge process are presented. This process involves coupling a bioreactor with effluent separation by microfiltration hollow fibres immersed directly in the bioreactor. The two pilot studies were conducted at Valley Sanitary District, Indio, California, for 5 months and in Maisons-Laffitte, France, for 1 year. The objectives were to demonstrate

Pierre Côté; Hervé Buisson; Charles Pound; Greg Arakaki




EPA Science Inventory

Particulate emissions from a group of municipal sludge incinerators with multiple-hearth furnaces, one with a fluidized-bed furnace were characterized. Three plants operated at or near autogenous burning conditions. Chemical element composition was determined for total and sized ...


Biotransformation of arsenic species by activated sludge and removal of bio-oxidised arsenate from wastewater by coagulation with ferric chloride  

Microsoft Academic Search

The potential of activated sludge to catalyse bio-oxidation of arsenite [As(III)] to arsenate [As(V)] and bio-reduction of As(V) to As(III) was investigated. In batch experiments (pH 7, 25°C) using activated sludge taken from a treatment plant receiving municipal wastewater non-contaminated with As, As(III) and As(V) were rapidly biotransformed to As(V) under aerobic condition and As(III) under anaerobic one without acclimatisation,

Harinaivo Anderson Andrianisa; Ayumi Ito; Atsushi Sasaki; Jiro Aizawa; Teruyuki Umita



Meta-Analysis of Mass Balances Examining Chemical Fate during Wastewater Treatment  

PubMed Central

Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (?), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale. This review examines over a dozen mass balances conducted for various organic wastewater contaminants, including prescription drugs, estrogens, fragrances, antimicrobials, and surfactants of differing sorption potential (hydrophobicity), here expressed as the 1-octanol?water partition coefficient (KOW) and the organic carbon normalized sorption coefficient (KOC). Major challenges to mass balances are the collection of representative samples and accurate quantification of chemicals in sludge. A meta-analysis of peer-reviewed data identified sorption potential as the principal determinant governing chemical persistence in biosolids. Occurrence data for organic wastewater compounds detected in digested sludge followed a simple nonlinear model that required only KOW or KOC as the input and yielded a correlation coefficient of 0.9 in both instances. The model predicted persistence in biosolids for the majority (>50%) of the input load of organic wastewater compounds featuring a log10KOW value of greater than 5.2 (log10KOC > 4.4). In contrast, hydrophobicity had no or only limited value for estimating, respectively, ? and the overall persistence of a chemical during conventional wastewater treatment. PMID:18800497



Benefits from Joint Treatment of Municipal and Poultry-Processing Wastewater  

NASA Astrophysics Data System (ADS)

The costs of treating wastewater from poultry-processing plants and municipalities are simulated for joint treatment and separate facilities. Three sizes of poultry processing plants (51,000 to 207,000 birds per day) and six sizes of communities (3,000 to 20,000 people) were studied, and costs were developed for lagoon, activated sludge, and trickling filter systems. Lagoon systems are cost effective both for separate and joint treatment. Trickling filter systems cost less than activated sludge systems when only domestic wastes are treated. The reverse is true when poultry processing wastes are introduced. When activated sludge or lagoon treatment is used, joint treatment gives a substantial cost saving for any size of poultry processing plant, regardless of community size. The potential savings from joint treatment are sufficient to pay for up to 6 miles (9.6 km) of gravity main transmission of poultry processing plant wastes to a municipal treatment plant.

Epp, Donald J.; Young, C. Edwin; Rossi, Daniel



Evaluation of the WHO helminth eggs criteria using a QMRA approach for the safe reuse of wastewater and sludge in developing countries.  


An analysis of the actual WHO recommendations to develop standards for the safe reuse of wastewater, excreta or sludge in agriculture using a quantitative microbial risk assessment (QMRA) is presented. The proposed values are defined using a risk-based model for Ascaris lumbricoides infection to assess the human risks associated with exposure to this pathogen from crops irrigated with polluted water, or from crops grown in biosolid-enriched soil. From the results it becomes evident that, with regard to helminth eggs, the WHO guidelines for wastewater reuse in agriculture seem more stringent than are needed in developing countries, while for the reuse of sludge they appear to be the opposite. Although more information is needed to confirm this conclusion, which was derived from a single piece of research, at the very least a more cautious approach is recommended when evaluating excreta or sludge for agricultural purposes in developing countries. Additionally, this work shows that the application of some barriers, other than wastewater and sludge treatment as suggested by WHO, can play an important role in controlling risks. PMID:21508556

Navarro, I; Jiménez, B



A review of the sustainable value of effluents and sludges from wastewater stabilization ponds  

Microsoft Academic Search

Sludges and liquids from wastewater stabilization ponds are cost effective by-products useful for agriculture, aquaculture and for manufacturing building materials. They represent valuable sustainable resources as raw materials to support fisheries for human consumption, to produce animal feed derived from single cell algal proteins and aquatic weeds. Biogas from waste fermentation represents a significant tertiary product.Stabilization ponds are dynamic, low-cost

Basavaling B. Hosetti; Stanley Frost



A Novel Technique for Phenolic Wastewater Treatment  

Microsoft Academic Search

Fresh water crisis and its degradation due to contamination by industrial and municipal waste highlighted. Phenol is one of the most common contaminant, the methods of treatment of phenolic wastewater discussed emphasis given on the aerobic biological treatment. Special attention has been paid to the biological treatment mentioning the drawbacks of the traditional methods. The relative advantages of various modern

H. M. Jena; G. K. Roy; R. K. Singh


Energy saving on wastewater treatment plants through improved online control: case study wastewater treatment plant Antwerp-South.  


This work provides a case study on how activated sludge modelling and computational fluid dynamics (CFD) can help to optimize the energy consumption of a treatment plant that is already equipped with an advanced control based on online nutrient measurements. Currently, aeration basins on wastewater treatment plant Antwerp-South are operated sequentially while flow direction and point of inflow and outflow vary as a function of time. Activated sludge modelling shows that switching from the existing alternating flow based control to a simultaneous parallel feeding of all aeration tanks saves 1.3% energy. CFD calculations also illustrate that the water velocity is still sufficient if some impellers in the aeration basins are shutdown. The simulations of the Activated Sludge Model No. 2d indicate that the coupling of the aeration control with the impeller control, and automatically switching off some impellers when the aeration is inactive, can save 2.2 to 3.3% of energy without affecting the nutrient removal efficiency. On the other hand, all impellers are needed when the aeration is active to distribute the oxygen. PMID:24622558

De Gussem, Kris; Fenu, Alessio; Wambecq, Tom; Weemaes, Marjoleine



Treatment of opium alkaloid containing wastewater in sequencing batch reactor (SBR)—Effect of gamma irradiation  

NASA Astrophysics Data System (ADS)

Aerobic biological treatment of opium alkaloid containing wastewater as well as the effect of gamma irradiation as pre-treatment was investigated. Biodegradability of raw wastewater was assessed in aerobic batch reactors and was found highly biodegradable (83-90% degradation). The effect of irradiation (40 and 140 kGy) on biodegradability was also evaluated in terms of BOD 5/COD values and results revealed that irradiation imparted no further enhancement in the biodegradability. Despite the highly biodegradable nature of wastewater, further experiments in sequencing batch reactors (SBR) revealed that the treatment operation was not possible due to sludge settleability problem observed beyond an influent COD value of 2000 mg dm -3. Possible reasons for this problem were investigated, and the high molecular weight, large size and aromatic structure of the organic pollutants present in wastewater was thought to contribute to poor settleability. Initial efforts to solve this problem by modifying the operational conditions, such as SRT reduction, failed. However, further operational modifications including addition of phosphate buffer cured the settleability problem and influent COD was increased up to 5000 mg dm -3. Significant COD removal efficiencies (>70%) were obtained in both SBRs fed with original and irradiated wastewaters (by 40 kGy). However, pre-irradiated wastewater provided complete thebain removal and a better settling sludge, which was thought due to degradation of complex structure by radiation application. Degradation of the structure was observed by GC/MS analyses and enhancement in filterability tests.

Bural, Cavit B.; Demirer, Goksel N.; Kantoglu, Omer; Dilek, Filiz B.



Comparison between filtrations at fixed transmembrane pressure and fixed permeate flux: application to a membrane bioreactor used for wastewater treatment  

Microsoft Academic Search

Membrane bioreactors for wastewater treatment must operate for long periods without chemical cleaning. This paper investigates the critical flux concept introduced by Field et al. as a means for achieving this goal. Experiments were conducted on a membrane bioreactor containing 600l of activated sludge, equipped with a 0.25m2 ceramic membrane and located in Compiegne wastewater treatment plant. Hydraulic retention time

L. Defrance; M. Y. Jaffrin



Methane and nitrous oxide emissions following anaerobic digestion of sludge in Japanese sewage treatment facilities.  


Methane (CH4) and nitrous oxide (N2O) are potent greenhouse gases with global warming potentials (expressed in terms of CO2-equivalents) of 28 and 265, respectively. When emitted to the atmosphere, they significantly contribute to climate change. It was previously suggested that in wastewater treatment facilities that apply anaerobic sludge digestion, CH4 continues to be emitted from digested sludge after leaving the anaerobic digester. This paper studies the CH4 and N2O emissions from anaerobically digested sludge in the subsequent sludge treatment steps. Two full-scale treatment plants were monitored over a 1-year period. Average emissions of CH4 and N2O were 509±72mg/m(3)-influent (wastewater) and 7.1±2.6mg/m(3)-influent, respectively. These values accounted for 22.4±3.8% of the indirect reduction in CO2-emissions when electricity was generated using biogas. They are considered to be significant. PMID:25194911

Oshita, Kazuyuki; Okumura, Takuya; Takaoka, Masaki; Fujimori, Takashi; Appels, Lise; Dewil, Raf



Evaluation and improvement of wastewater treatment plant performance using BioWin  

NASA Astrophysics Data System (ADS)

In this study, the activated sludge model implemented in the BioWin® software was validated against full-scale wastewater treatment plant data. Only two stoichiometric parameters (Y p/acetic and the heterotrophic yield (Y H)) required calibration. The value 0.42 was used for Y p/acetic in this study, while the default value of the BioWin® software is 0.49, making it comparable with the default values of the corresponding parameter (yield of phosphorus release to substrate uptake (Y_{PO_4 } )) used in ASM2, ASM2d, and ASM3P, respectively. Three scenarios were evaluated to improve the performance of the wastewater treatment plant, the possibility of wasting sludge from either the aeration tank or the secondary clarifier, the construction of a new oxidation ditch, and the construction of an equalization tank. The results suggest that construction of a new oxidation ditch or an equalization tank for the wastewater treatment plant is not necessary. However, sludge should be wasted from the aeration tank during wet weather to reduce the solids loading of the clarifiers and avoid effluent violations. Therefore, it is recommended that the design of wastewater treatment plants (WWTPs) should include flexibility to operate the plants in various modes. This is helpful in selection of the appropriate operating mode when necessary, resulting in substantial reductions in operating costs.

Oleyiblo, Oloche James; Cao, Jiashun; Feng, Qian; Wang, Gan; Xue, Zhaoxia; Fang, Fang



Image analysis of sludge aggregates obtained at preliminary treatment of sewage.  


The results of wastewater treatment by Al and Fe salts and by electrocoagulation with aluminum electrodes are discussed and interpreted. Those processes used alone or combined with biological treatment, were analyzed for 50 and 90% removal of phosphates. Scanning electron microscopy (SEM) of the resulting sludge from three coagulation processes defined the perimeter P and area A of 129-142 differently sized objects in each contrast-enhanced image. Plots of lg A against lg P revealed that the analyzed sludge samples were made of self-similar aggregates-flocs with fractal characteristics. The slope of 'log plots' was used to determine surface fractal dimension Da, which was extrapolated to volumetric fractal dimension Dv. Dv was applied in a quantitative description of sludge aggregates-flocs. Aggregates-flocs of sludge obtained by Al ions (pre-polymerized Al and electrocoagulation) were characterized by higher values of Dv in comparison with sludge obtained by iron salts. The structure of {Al(OH)3} and {Fe(OH)3} aggregate-flocs was graphically simulated to determine the effect of size distribution and Dv on sweep flocculation and sludge separation and dehydration. Phosphate removal efficiency of 50% occurred at low ratios of Al:P and Fe:P. Adsorption-charge neutralization was suggested during coagulation with pre-polymerized coagulants, and sweep flow mechanism during electrocoagulation. PMID:25259494

Smoczy?ski, L; Ratnaweera, H; Kosobucka, M; Kvaal, K; Smoczy?ski, M



Cultivation of Green Algae Chlorella sp. in Different Wastewaters from Municipal Wastewater Treatment Plant  

Microsoft Academic Search

The objective of this study was to evaluate the growth of green algae Chlorella sp. on wastewaters sampled from four different points of the treatment process flow of a local municipal wastewater treatment\\u000a plant (MWTP) and how well the algal growth removed nitrogen, phosphorus, chemical oxygen demand (COD), and metal ions from\\u000a the wastewaters. The four wastewaters were wastewater before

Liang Wang; Min Min; Yecong Li; Paul Chen; Yifeng Chen; Yuhuan Liu; Yingkuan Wang; Roger Ruan



Applications of Energy Efficiency Technologies in Wastewater Treatment Facilities  

E-print Network

"Depending on the level and type of treatment, municipal wastewater treatment (WWT) can be an energy intensive process, constituting a major cost for the municipal governments. According to a 1993 study wastewater treatment plants consume close to 1...

Chow, S.; Werner, L.; Wu, Y. Y.; Ganji, A. R.


Performance evaluation and spatial sludge distribution at facultative and maturation ponds treating wastewater from an international airport.  


This paper presents a performance evaluation of facultative and maturation ponds in series treating wastewater from a large and intensively used international airport in Brazil, based on 16 years of regular monitoring. The wastewater from the airport showed similar or slightly lower concentrations compared to typical domestic sewage for most of the quality parameters. The contribution of effluents with possible industrial features (aircraft toilets and hangar effluent) did not seem to have adversely affected the characteristics of the influent in terms of aptitude to biological treatment. Overall, the ponds operated under very underloaded conditions (mean loading rate of 44 kg biochemical oxygen demand/ha.d in the facultative pond) and presented a satisfactory quality in terms of effluent concentrations for most parameters. A bathymetric survey of the ponds was done manually by a low-cost measurer constructed specifically for this purpose. After 27 years of operation, only 25% and 18% of the volumes of the facultative and maturation ponds were occupied by sludge. Specific sludge accumulation rates were 0.0071 m³/passenger.year for the facultative pond and 0.00017 m³/passenger.year for the maturation pond. PMID:25051468

Passos, Ricardo Gomes; von Sperling, Marcos; Ribeiro, Thiago Bressani



Aquatic Plants and Wastewater Treatment (an Overview)  

NASA Technical Reports Server (NTRS)

The technology for using water hyacinth to upgrade domestic sewage effluent from lagoons and other wastewater treatment facilities to secondary and advanced secondary standards has been sufficiently developed to be used where the climate is warm year round. The technology of using emergent plants such as bulrush combined with duckweed is also sufficiently developed to make this a viable wastewater treatment alternative. This system is suited for both temperate and semi-tropical areas found throughout most of the U.S. The newest technology in artificial marsh wastewater treatment involves the use of emergent plant roots in conjunction with high surface area rock filters. Smaller land areas are required for these systems because of the increased concentration of microorganisms associated with the rock and plant root surfaces. Approximately 75 percent less land area is required for the plant-rock system than is required for a strict artificial wetland to achieve the same level of treatment.

Wolverton, B. C.



Granular sludge growth under different reactor liquid surface tensions in lab-scale upflow anaerobic sludge blanket reactors treating wastewater from sugar-beet processing  

Microsoft Academic Search

The formation of anaerobic granular sludge on wastewater from sugar-beet processing was examined in upflow anaerobic sludge blanket reactors. Two strategies were investigated: addition of high-energy substrate, i.e. sugars, and varying the reactor liquid surface tension. When there were insufficient amounts of sugars i.e. less than 7% of the chemical O2 demand of the influent, no granulation was observed; moreover

J. Thaveesri; B. Liessens; W. Verstraete



Effect of Ozone on Viability of Activated Sludge Detected by Oxygen Uptake Rate (OUR) and Adenosine5?-triphosphate (ATP) Measurement  

Microsoft Academic Search

The current study focused on treatment of phenolic wastewater using an integrated process – dosing of ozone directly to activated sludge. The main goal was to analyze the effect of ozonation on viability of activated sludge in different systems – activated sludge in distilled water and activated sludge in wastewater. Two viability detection methods, oxygen uptake (OUR) rate and adenosine-5'-triphosphate

Oliver Järvik; Sven Kamenev; Kaja Kasemets; Inna Kamenev



Transformation of PVP coated silver nanoparticles in a simulated wastewater treatment process and the effect on microbial communities  

PubMed Central

Background Manufactured silver nanoparticles (AgNPs) are one of the most commonly used nanomaterials in consumer goods and consequently their concentrations in wastewater and hence wastewater treatment plants are predicted to increase. We investigated the fate of AgNPs in sludge that was subjected to aerobic and anaerobic treatment and the impact of AgNPs on microbial processes and communities. The initial identification of AgNPs in sludge was carried out using transmission electron microscopy (TEM) with energy dispersive X-ray (EDX) analysis. The solid phase speciation of silver in sludge and wastewater influent was then examined using X-ray absorption spectroscopy (XAS). The effects of transformed AgNPs (mainly Ag-S phases) on nitrification, wastewater microbial populations and, for the first time, methanogenesis was investigated. Results Sequencing batch reactor experiments and anaerobic batch tests, both demonstrated that nitrification rate and methane production were not affected by the addition of AgNPs [at 2.5 mg Ag L-1 (4.9 g L-1 total suspended solids, TSS) and 183.6 mg Ag kg -1 (2.9 g kg-1 total solids, TS), respectively]. The low toxicity is most likely due to AgNP sulfidation. XAS analysis showed that sulfur bonded Ag was the dominant Ag species in both aerobic (activated sludge) and anaerobic sludge. In AgNP and AgNO3 spiked aerobic sludge, metallic Ag was detected (~15%). However, after anaerobic digestion, Ag(0) was not detected by XAS analysis. Dominant wastewater microbial populations were not affected by AgNPs as determined by DNA extraction and pyrotag sequencing. However, there was a shift in niche populations in both aerobic and anaerobic sludge, with a shift in AgNP treated sludge compared with controls. This is the first time that the impact of transformed AgNPs (mainly Ag-S phases) on anaerobic digestion has been reported. Conclusions Silver NPs were transformed to Ag-S phases during activated sludge treatment (prior to anaerobic digestion). Transformed AgNPs, at predicted future Ag wastewater concentrations, did not affect nitrification or methanogenesis. Consequently, AgNPs are very unlikely to affect the efficient functioning of wastewater treatment plants. However, AgNPs may negatively affect sub-dominant wastewater microbial communities. PMID:23497481



A pilot study for oil refinery wastewater treatment using a fixed-film bioreactor  

Microsoft Academic Search

Biological treatment of industrial oil refinery wastewater is a well-established method for remediation of these wastes. We have designed a new bioreactor system to increase the efficiency of biological treatment systems by (1) allowing greater organic loads, (2) minimizing production of sludge waste by-products, and (3) increasing process stability and resistance to shock loading. A fixed-film bioreactor system was constructed

Chih-Ju G Jou; Guo-Chiang Huang



Emergency Planning for Municipal Wastewater Treatment Facilities.  

ERIC Educational Resources Information Center

This manual for the development of emergency operating plans for municipal wastewater treatment systems was compiled using information provided by over two hundred municipal treatment systems. It covers emergencies caused by natural disasters, civil disorders and strikes, faulty maintenance, negligent operation, and accidents. The effects of such…

Lemon, R. A.; And Others


Human Pharmaceuticals in Wastewater Treatment Processes  

Microsoft Academic Search

The presence of human pharmaceutical compounds in surface waters is an emerging issue in environmental science. In this study the occurrence and behavior of human pharmaceuticals in a variety of wastewater treatment processes is reviewed. Although some groups are not affected by sewage treatment processes others are amenable to degradation, albeit incomplete. While water purification techniques such as granular activated

O. A. H. Jones; N. Voulvoulis; J. N. Lester




Microsoft Academic Search

This work evaluates the environmental impact of Wastewater Treatment Plants (WTP) based on data generated by the exergy analysis, calculating and applying environmental impact indexes for two WTP located in the Metropolitan Area of São Paulo. The environmental impact of the waste water treatment plants was done by means of evaluating two environmental impact exergy based indexes: the environmental exergy

C. H. Mora; Cidade Universitária


Innovative anaerobic/upflow sludge blanket filtration bioreactor for phosphorus removal from wastewater.  


Phosphorus is the key element to remove from aquatic environments to limit the growth of aquatic plants and algae and, thus, to control eutrophication. Because the upflow sludge blanket filtratio' (USBF) process, without addition of metal salts, entails low efficiency for phosphorus removal, we added an anaerobic reactor to the USBF bioreactor in order to promote the simultaneous removal of phosphorus and nitrogen from wastewater. The results revealed that the anaerobic/USBF bioreactor had a phosphorus removal efficiency up to 86%, with a sludge retention time (SRT) of 10 days, a hydraulic retention time (HRT) of 24 hours and an optimum COD/N/P ratio of 100/5/1. This ratio also improved the compaction quality of the sludge blanket in the USBF clarifier. The average specific phosphate uptake rate in the aerobic zone and the average specific phosphate release rate in the anaerobic reactor were 0.014 mg PO4-P removed/(g VSS x min) and 0.0525 mg PO4-P released/(g VSS x min), respectively. Secondary phosphorus release in the USBF clarifier was heightened with increasing HRT. Hence, the optimum total HRT can be selected between 16 and 24 hours based on effluent quality. Effluent phosphorus of about 1 mg/L was provided for wastewater with the COD/N/P ratio of 100/5/1 at the sludge age of 10 days and total HRT of 16 hours. This study illustrated that the anaerobic/USBF bioreactor at the optimum operational conditions can be an effective process for phosphorus removal from municipal wastewater. PMID:21877530

Khorsandi, H; Movahedyan, H; Bina, B; Farrokhzadeh, H



Wastewater treatment\\/anaerobic processes  

Microsoft Academic Search

A review covers microbiology and mechanisms; soil anaerobiosis; denitrification in soil-water systems; wastewater denitrification; process developments, e.g., to produce relatively pure methane by subjecting conventional digesters to pressures of 2 to 5 atm gage; process applications for industrial wastes, e.g., for the fermentation of brewery wastes to produce methane and the conversion of coal gasification products to methane; process applications

S. Ghosh; M. L. Packer



Applications of nanotechnology in water and wastewater treatment  

E-print Network

Applications of nanotechnology in water and wastewater treatment Xiaolei Qu, Pedro J.J. Alvarez and wastewater treatment Water reuse Sorption Membrane processes Photocatalysis Disinfection Microbial control. Nanotechnology holds great potential in advancing water and wastewater treatment to improve treatment efficiency

Alvarez, Pedro J.


Occurrence and risk assessment of nonylphenol and nonylphenol ethoxylates in sewage sludge from different conventional treatment processes.  


In the present work, the concentrations of the organic pollutants nonylphenol (NP) and nonylphenol mono- and diethoxylates (NP1EO and NP2EO, respectively) in primary, secondary, mixed, aerobically-digested, anaerobically-digested, dehydrated, compost and lagoon sludge samples from different sludge treatments have been evaluated. Toxicological risk assessment of these compounds in sludge and sludge-amended soil has also been reported. NP, NP1EO and NP2EO were monitored in sludge samples obtained from treatment plants located in Andalusia (south of Spain) based on anaerobic treatments (11 anaerobic-digestion wastewater treatment plants and 3 anaerobic wastewater stabilization ponds) or on aerobic treatments (3 aerobic-digestion wastewater treatment plants, 1 dehydration treatment plant and 2 composting plants). The sum of NP, NP1EO and NP2EO (NPE) concentrations has been evaluated in relation to the limit value of 50 mg/kg set by the European Union Sludge Directive draft published in April 2000 (Working Document on Sludge). In most of the samples, NP was present at higher concentration levels (mean value 88.0 mg/kg dm) than NP1EO (mean value 33.8 mg/kg dm) and NP2EO (mean value 14.0 mg/kg dm). The most contaminated samples were compost, anaerobically-digested sludge, lagoon sludge and aerobically-digested sludge samples, which contained NPE concentrations in the ranges 44-962 mg/kg dm, 8-669 mg/kg dm, 27-319 mg/kg dm and 61-282 mg/kg dm, respectively. Risk quotients, expressed as the ratios between environmental concentrations and the predicted no-effect concentrations, were higher than 1 for NP, NP1EO and NP2EO in the 99%, 92% and 36% of the studied samples, respectively; and higher than 1 in the 86%, 6% and 2%, respectively, after sludge application to soil, leading to a significant ecotoxicological risk mainly due to the presence of NP. PMID:19896162

González, M M; Martín, J; Santos, J L; Aparicio, I; Alonso, E




EPA Science Inventory

This report describes development of a time-dependent computerized model for composting of wastewater treatment plant sludge with forced aeration of the pile. The work was undertaken because, in the past, development of the composting process for wastewater sludge has been almost...


Co-combustion of sludge with coal  

Microsoft Academic Search

Utilisation of waste-water sludge is one of the most difficult processes of environment protection because of the high moisture and contents of harmful substances. The waste-water treatment systems in Poland, especially in small towns, are often not separate from industrial sewage systems and this causes relatively large contents of heavy metals and other toxic substances in the sludge. Incineration is

Jan Nadziakiewicz; Micha? Kozio?



Are standard wastewater treatment plant design methods suitable for any municipal wastewater?  


The design and operational parameters of an activated sludge system were analyzed treating the municipal wastewaters in Istanbul. The design methods of ATV131, Metcalf & Eddy together with model simulations were compared with actual plant operational data. The activated sludge model parameters were determined using 3-month dynamic data for the biological nutrient removal plant. The ATV131 method yielded closer sludge production, total oxygen requirement and effluent nitrogen levels to the real plant after adopting correct influent chemical oxygen demand (COD) fractionation. The enhanced biological phosphorus removal (EBPR) could not easily be predicted with ATV131 method due to low volatile fatty acids (VFA) potential. PMID:22699337

Insel, G; Güder, B; Güne?, G; Ubay Cokgor, E



Energy efficiency in municipal wastewater treatment plants: Technology assessment  

SciTech Connect

The New York State Energy Research and Development Authority (NYSERDA) estimates that municipal wastewater treatment plants (WWTPs) in New York State consume about 1.5 billion kWh of electricity each year for sewage treatment and sludge management based on the predominant types of treatment plants, the results of an energy use survey, and recent trends in the amounts of electricity WWTPs use nationwide. Electric utilities in New York State have encouraged demand-side management (DSM) to help control or lower energy costs and make energy available for new customers without constructing additional facilities. This report describes DSM opportunities for WWTPs in New York State; discusses the costs and benefits of several DSM measures; projects energy impact statewide of the DSM technologies; identifies the barrier to implementing DSM at WWTPs; and outlines one possible incentive that could stimulate widespread adoption of DSM by WWTP operators. The DSM technologies discussed are outfall hydropower, on-site generation, aeration efficiency, time-of-day electricity pricing, and storing wastewater.




Treatment of textile wastewater by Fenton's reagent  

Microsoft Academic Search

Treatment of textile wastewaters from a dyeing and finishing mill by Fenton's reagent is investigated. The experimental results are assessed in terms of COD and color (turbidity) reductions to determine the treatment efficiency of the Fenton's process. Operating variables, such as the pH, amounts of H2O2 and FeSO4, time of Fenton's treatment and amounts of polyaluminum chloride (PAC) and polymer,

S. H. Lin; C. F. Peng



Most modern wastewater treatment systems rely on microbial processes to remove contaminants. This makes wastewater  

E-print Network

Most modern wastewater treatment systems rely on microbial processes to remove contaminants. This makes wastewater treatment one of the largest biotechnology industries in the world. In New Zealand alone, about 1.5 billion litres of treated domestic wastewater is discharged each day

Auckland, University of


Treatment of textile wastewater by chemical methods for reuse  

Microsoft Academic Search

Treatment of wastewater effluent from the secondary wastewater treatment plant of a dyeing and finishing mill is investigated for possible reuse. The treatment system employed in the present study consists of an electrochemical method, chemical coagulation and ion exchange. The electrochemical method and chemical coagulation are intended primarily to remove color, turbidity (NTU) and COD concentration of the wastewater effluent

Sheng H. Lin; Ming L. Chen



Wastewater treatment and energy : an analysis on the feasibility of using renewable energy to power wastewater treatment plants in Singapore  

E-print Network

Wastewater treatment is a very energy intensive industry. Singapore has a state-of-the-art wastewater treatment system that uses a number of sustainable techniques that greatly improve its overall efficiency. The centralized ...

Foley, Kevin John



Wetlands for wastewater treatment: Opportunities and limitations  

Microsoft Academic Search

This paper gives some introductory information on the use of wetlands for wastewater treatment. It focuses mainly on the functioning of constructed wetlands, in particular surface-flow and infiltration wetlands. The various processes which lead to water purification are briefly explained, in relation to the factors which influence their efficiency. The possibilities for optimization of the design and management of such

Jos T. A. Verhoeven; Arthur F. M. Meuleman



Isolation of Nitrospira belonging to Sublineage II from a Wastewater Treatment Plant  

PubMed Central

Nitrite oxidation is a key step in nitrogen removal in biological wastewater treatment plants. Recently, two phylogenetically different Nitrospira (sublineages I and II) have been recognized as the numerically dominant nitrite-oxidizing bacteria in wastewater treatment plants. However, Nitrospira sublineage II inhabiting activated sludge was not isolated and its detailed properties were unclear. In this study, we developed a new method for the isolation of Nitrospira forming micro-colonies using a cell sorter. We obtained a novel pure strain “Nitrospira japonica” from the activated sludge. Subsequently, phylogenetic and physiological analyses revealed that Nitrospira japonica belongs to sublineage II and grew in medium containing formate. This method has the potential to isolate other uncultured microorganisms forming micro-colonies. PMID:24005844

Ushiki, Norisuke; Fujitani, Hirotsugu; Aoi, Yoshiteru; Tsuneda, Satoshi



[Modeling and dynamic simulation of the multimode anaerobic/anoxic/aerobic wastewater treatment process].  


Mathematical modeling is a useful tool for professional education, process development, design evaluation, operational optimization and automatic control of the wastewater treatment system, and has been extensively applied in numerous full-scale wastewater treatment plants. The ASM2d model was calibrated by the process data, and used to simulate 15 operational test runs of the multimode anaerobic/anoxic/aerobic (AAO) process. After calibration, the model was capable of simulating the sludge concentrations and effluent data in 15 test runs of the multimode AAO system. The dynamic simulation results showed an overall good agreement between the measured and simulated data, for both effluent data and sludge concentrations, with a good reproduction of dynamic processes in AO test runs. PMID:23798127

Zhou, Zhen; Wu, Zhi-Chao; Wang, Zhi-Wei; Du, Xing-Zhi; Jiang, Ling-Yan; Xing, Can



Occurrence and removal of estrogens in Brazilian wastewater treatment plants.  


This paper evaluated the occurrence and removal efficiency of four estrogenic hormones in five biological wastewater treatment plants (WWTPs), located in the State of Ceará, Brazil. The five WWTPs comprised: two systems consisted of one facultative pond followed by two maturation ponds, one facultative pond, one activated sludge (AS) system followed by a chlorination step, and one upflow anaerobic sludge blanket (UASB) reactor followed by a chlorination step. Estrogen occurrence showed a wide variation among the analyzed influent and effluent samples. Estrone (E1) showed the highest occurrence in the influent (76%), whereas both 17?-estradiol (E2) and 17?-ethynylestradiol (EE2) presented a 52% occurrence, and the compound 17?-estradiol 17-acetate (E2-17A), a 32% one. The occurrence in the effluent samples was 48% for E1, 28% for E2, 12% for E2-17A, and 40% for EE2. The highest concentrations of E1 and EE2 hormones in the influent were 3050 and 3180 ng L(-1), respectively, whereas E2 and E2-17A had maximum concentrations of 776 and 2300 ng L(-1), respectively. The lowest efficiencies for the removal of estrogenic hormones were found in WWTP consisted of waste stabilization ponds, ranging from 54 to 79.9%. The high-rate systems (AS and UASB), which have chlorination as post-treatment, presented removal efficiencies of approximately 95%. PMID:24858226

Pessoa, Germana P; de Souza, Neyliane C; Vidal, Carla B; Alves, Joana A C; Firmino, Paulo Igor M; Nascimento, Ronaldo F; dos Santos, André B



Hydrolysis of macromolecular components of primary and secondary wastewater sludge by thermal hydrolytic pretreatment.  


A laboratory simulation of the thermal hydrolytic pretreatment (THP) process was performed on wastewater sludge, as well as key macromolecular components: proteins, lipids, and polysaccharides. Hydrolysis temperatures from 130 to 220 degrees C were investigated. The objectives of this study were to determine how and over which temperature range THP specifically affects sludge components, and whether hydrolysis temperature can be used to minimize the previously reported drawbacks of THP such as high total ammonia nitrogen (TAN) loads and the production of highly-colored recalcitrant organics. In addition, the applicability of THP to primary sludge (PS) was investigated. The breakdown of proteins, lipids, and polysaccharides was determined to be temperature dependent, and both waste activated sludge (WAS) and PS responded similarly to THP apart from intrinsic differences in lipid and protein content. Pure carbohydrate solutions were not largely converted to mono- or dimeric reducing sugar units at temperatures below 220 degrees C, however significant caramelization of starch and production of dextrose and maltose was observed to occur at 220 degrees C. Volatile fatty acid production during thermal hydrolysis was largely attributed to the breakdown of unsaturated lipids, and long-chain fatty acid production was not significant in terms of previous reports of methanogenic inhibition. Ammonia was produced from protein during thermal hydrolysis, however solids loading rather than thermal hydrolysis temperature appeared to be a more meaningful control for ammonia levels in downstream anaerobic digestion. PMID:19695659

Wilson, Christopher A; Novak, John T



Wastewater treatment using flocculation, coagulation, and flotation. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the design, development, and evaluation of flocculation coagulation and flotation processes for the treatment of sewage and industrial wastes. Citations examine technology requirements and limitations, activated sludge and anaerobic processes, chlorination, runoff pollution control, wastewater recycling and reuse, and materials recovery.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)




Wastewater treatment using flocculation, coagulation, and flotation. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the design, development, and evaluation of flocculation coagulation and flotation processes for the treatment of sewage and industrial wastes. Citations examine technology requirements and limitations, activated sludge and anaerobic processes, chlorination, runoff pollution control, wastewater recycling and reuse, and materials recovery.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)




Kinetics of biologically induced phosphorus precipitation in waste-water treatment  

Microsoft Academic Search

In waste-water treatment plants with enhanced biological phosphorus removal (EBPR), a part of the phosphorus can be eliminated by chemical precipitation. In experiments with inactivated sludge containing relatively high concentrations of dissolved calcium (?1.5molm?3) and phosphorus (?1molm?3), a pH-sensitive and partly reversible precipitation of calcium phosphates was observed at pH values below 8.0. A dynamic model was formulated on the

M. Maurer; D. Abramovich; H. Siegrist; W. Gujer



Wastewater treatment using flocculation, coagulation, and flotation. (Latest citations from the NTIS bibliographic database). NewSearch  

SciTech Connect

The bibliography contains citations concerning the design, development, and evaluation of flocculation coagulation and flotation processes for the treatment of sewage and industrial wastes. Citations examine technology requirements and limitations, activated sludge and anaerobic processes, chlorination, runoff pollution control, wastewater recycling and reuse, and materials recovery. (Contains 250 citations and includes a subject term index and title list.)

Not Available



Comparisons of the Methane Production Yield Coefficient from Anaerobic Microbial Assemblages in the Anaerobic Treatment of Wastewater  

Microsoft Academic Search

Mixed-microbial assemblages from a septic tank, leachate, sediment samples from a coastal area, sludge from the digester of a brewery wastewater treatment plant and acidic sulfate soil samples were compared on the basis of methane yield coefficient under anaerobic condition. The biomass inoculum of all these mixed culture was started up at ambient temperature (30±1 0 C) by a synthetic