scholarly journals Ultrafiltration Process in Disinfection and Advanced Treatment of Tertiary Treated Wastewater

Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 221
Author(s):  
Rafał Tytus Bray ◽  
Katarzyna Jankowska ◽  
Eliza Kulbat ◽  
Aneta Łuczkiewicz ◽  
Aleksandra Sokołowska

The paper presents the results of research on the use of ultrafiltration, using membranes of 200 and 400 kDa separation, for disinfection of municipal treated wastewater. The research was conducted on a fractional technical scale using real municipal treated wastewater from two large wastewater treatment plants treating most of the wastewater over the one-million polycentric Gdańsk agglomeration (1.2 million inhabitants). UF 200 kDa and UF 400 kDa processes enabled further improvement of the physical and chemical parameters of treated wastewater. Total phosphorus (to below 0.2 mg/L–UF 200 kDa, 0.13 mg/L–UF 400 kDa) and turbid substances (to below 0.2 mg/L, both membranes) were removed in the highest degree. COD was reduced efficiently (to below 25.6 mgO2/L–UF 200 kDa, 26.8 mgO2/L–UF 400 kDa), while total nitrogen was removed to a small extent (to 7.12 mg/L–UF 200 kDa and 5.7 mg/L–UF 400 kDa. Based on the reduction of indicator bacteria; fecal coliforms including E. coli (FC) and fecal enterococci (FE) it was found that the ultrafiltration is an effective method of disinfection. Not much indicator bacterial were observed in the permeate after processes (UF 200 kDa; FC—5 CFU/L; FE—1 CFU/L and UF 400 kDa; FC—70 CFU/L; FE—10 CFU/L. However, microscopic analysis of prokaryotic cells and virus particles showed their presence after the application of both membrane types; TCN 3.0 × 102 cells/mL–UF 200 kDa, 5.0 × 103 cells/mL–UF 400 kDa, VP 1.0 × 105/mL. The presence of potentially pathogenic, highly infectious virus particles means that ultrafiltration cannot be considered a sufficient disinfection method for treated wastewater diverted for reuse or discharged from high load wastewater treatment plants to recreational areas. For full microbiological safety it would be advisable to apply an additional disinfection method (e.g., ozonation).

2010 ◽  
Vol 61 (6) ◽  
pp. 1383-1392 ◽  
Author(s):  
A. Łuczkiewicz ◽  
S. Fudala-Książek ◽  
K. Jankowska ◽  
B. Quant ◽  
K. Olańczuk-Neyman

The occurrence of resistance patterns among wastewater fecal coliforms was determined in the study. Susceptibility of the isolates was tested against 19 antimicrobial agents: aminoglycosides, aztreonam, carbapenems, cephalosporines, β-lactam/β-lactamase inhibitors, penicillines, tetracycline, trimethoprim/sulfamethoxazole, and fluoroquinolones. Additionally the removal of resistant isolates was evaluated in the laboratory-scale wastewater treatment model plant (M-WWTP), continuously supplied with the wastewater obtained from the full-scale WWTP. Number of fecal coliforms in raw (after mechanical treatment) and treated wastewater, as well as in aerobic chamber effluent was determined using selective medium. The selected strains were identified and examined for antibiotic resistance using Phoenix Automated Microbiology System (BD Biosciences, USA). The strains were identified as Escherichia coli (n = 222), Klebsiella pneumoniae ssp. ozaenae (n = 9), and Pantoea agglomerans (n = 1). The isolate of P. agglomerans as well as 48% of E. coli isolates were sensitive to all antimicrobials tested. The most frequent resistance patterns were found for ampicillin: 100% of K. pneumoniae ssp. ozaenae and 41% of E. coli isolates. Among E. coli isolates 12% was regarded as multiple antimicrobial resistant (MAR). In the studied M-WWTP, the applied activated sludge processes reduced considerably the number of fecal coliforms, but increased the ratio of antimicrobial-resistant E. coli isolates to sensitive ones, especially among strains with MAR patterns.


2016 ◽  
Vol 74 (12) ◽  
pp. 2935-2945 ◽  
Author(s):  
C. Silva ◽  
J. Saldanha Matos ◽  
M. J. Rosa

High quality services of wastewater treatment require a continuous assessment and improvement of the technical, environmental and economic performance. This paper demonstrates a comprehensive approach for benchmarking wastewater treatment plants (WWTPs), using performance indicators (PIs) and indices (PXs), in a ‘plan-do-check-act’ cycle routine driven by objectives. The performance objectives herein illustrated were to diagnose the effectiveness and energy performance of an oxidation ditch WWTP. The PI and PX results demonstrated an effective and reliable oxidation ditch (good–excellent performance), and a non-reliable UV disinfection (unsatisfactory–excellent performance) related with influent transmittance and total suspended solids. The energy performance increased with the treated wastewater volume and was unsatisfactory below 50% of plant capacity utilization. The oxidation ditch aeration performed unsatisfactorily and represented 38% of the plant energy consumption. The results allowed diagnosing opportunities for improving the energy and economic performance considering the influent flows, temperature and concentrations, and for levering the WWTP performance to acceptable–good effectiveness, reliability and energy efficiency. Regarding the plant reliability for fecal coliforms, improvement of UV lamp maintenance and optimization of the UV dose applied and microscreen recommissioning were suggested.


2013 ◽  
Vol 8 (1) ◽  
pp. 83-94
Author(s):  
G. E. Whitby ◽  
O. Lawal ◽  
P. Ropic ◽  
S. Shima ◽  
B. Ferran ◽  
...  

The treatment objective of an ultraviolet disinfection system used in a wastewater application is to protect the aquatic environment and users of water that receive discharges from wastewater treatment plants. To ensure this objective is adequately met it is important to validate, or verify equipment performance for a specific application. The widely accepted method for completing this validation is by determining the UV dose delivery performance using biodosimetry. Until now a standard bioassay did not exist for UV equipment that is used to disinfect treated wastewater from a biological treatment plant that is achieving an average effluent quality of less than 30 mg/L BOD/TSS and disinfection requirements of 126 cfu/100 mL E. coli over a 30 day geometric mean or 200 cfu/100 mL fecal coliforms over a 30 day geometric mean. A uniform bioassay for wastewater UV equipment that can be widely adopted by industry and regulatory bodies was developed and approved by the International Ultraviolet Association. This bioassay for UV equipment is described.


2018 ◽  
Vol 44 ◽  
pp. 00133 ◽  
Author(s):  
Adriana Osińska ◽  
Ewa Korzeniewska ◽  
Monika Harnisz ◽  
Sebastian Niestępski

Treated wastewater evacuated into the aquatic environment is a potential reservoir of pathogenic and virulent bacteria. The aim of this study was to analyze the presence of genes encoding virulence in E. coli bacteria in samples of untreated (UWW) and treated (TWW) wastewater from 13 wastewater treatment plants deploying various sewage treatment methods. Wastewater samples were passed through polycarbonate membrane filters, and genomic DNA was extracted. Virulence genes specific for E. coli were detected by standard PCR and were grouped according to their association with different pathotypes. The stx2 gene was most prevalent in samples of UWW, and the eae gene was most frequently detected in samples of TWW. An analysis of virulence markers revealed a predominance of genes characteristic of STEC and EIEC pathotypes. The highest variability of virulence genes was observed in wastewater treatment plants where sewage is treated mechanically and biologically, and the lowest variability was noted in plants deploying the A2/O treatment process (3-stage Bardenpho). In several plants, the prevalence of virulence genes increased after treatment. The results of this study suggest that wastewater treatment plants are significant reservoirs of virulent bacteria. The evacuation of TWW into water bodies can contribute to the dissemination of virulence genes in the environment, which poses a serious health hazard for humans and animals.


2021 ◽  
Vol 3 (7) ◽  
Author(s):  
T. S. C. Quintão ◽  
F. G. Silva ◽  
A. L. Pereira ◽  
W. N. Araújo ◽  
P. M. Oliveira ◽  
...  

AbstractHuman enteric viruses, such as enteric adenoviruses (HAdV), are known to be involved with gastrointestinal disorders, especially acute gastroenteritis. Several studies have used HAdV as an indicator of water quality, since they are considered highly stable and widely distributed viruses in water matrices. The aim of this study was to detect and genotype HAdVs in water matrices impacted by discharges of treated effluents from wastewater treatment plants (WWTPs). Wastewater treatment plants from the sanitary system of the Brazilian Federal District were assessed in 2018 and 2019. Samples were collected upstream and downstream from discharge points for each WWTP. Viral concentration based on adsorption-elution and conventional PCR was used for molecular detection, and positive samples were sequenced for phylogenetic analysis. Pluviosity data for the period in which the samples were collected were obtained. Our results demonstrated the presence of HAdVs in 27.2% (61/224) of the samples. The positivity was significantly higher in downstream samples compared to upstream. Moreover, the HAdV positivity was higher in downstream samples collected from receiving water bodies impacted by secondary-level WWTPs in comparison with those impacted by tertiary-level WWTPs. Phylogenetic analysis demonstrated the presence of genotypes 40 and 41, with prevalence of HAdV genotype 41. Despite the predominance of HAdV-41, an increasing frequency of the HAdV-40 was associated with higher pluviosity. In conclusion, this study is the first documentation in the Brazilian Federal District dealing with the prevalence and diversity of HAdVs in several WWTP, along with their correlation with rainfall index.


2012 ◽  
Vol 65 (4) ◽  
pp. 589-595 ◽  
Author(s):  
A. Ouali ◽  
H. Jupsin ◽  
J. L. Vasel ◽  
L. Marouani ◽  
A. Ghrabi

Korba wastewater treatment plant is a conventional activated sludge followed by three maturation ponds (MP1, MP2, MP3) in series acting as a tertiary treatment. The first study of wastewater treatment plants showed that the effluent concentration of Escherichia coli and enterococci at the outlet of the (MP3) varies between 103 and 104CFU/100 ml. After the hydrodynamic study conducted by Rhodamine WT which showed short-circuiting in the MP1, two baffles were introduced in the first maturation pond (MP1) to improve the hydrodynamic and the sanitary performances. The second hydraulic study showed that the dispersion number ‘d’ was reduced from 1.45 to 0.43 by this engineering intervention and the Peclet number was raised from 0.69 to 2.32. The hydraulic retention time was increased by 14 h. Because of well-designed baffles, the removal efficiency of E. coli and enterococci was raised between 0.2 and 0.7 log units for the first maturation pond.


2021 ◽  
Author(s):  
Adamo R. Petosa ◽  
Monica Nowierski ◽  
Viviane Yargeau

Abstract Bioanalytical tools, namely in vitro bioassays, can be employed in tandem with chemical analyses to assess the efficacy of wastewater treatment and the potential for adverse effects from the discharges of wastewater into receiving waters. In the present study, samples of untreated wastewater (i.e. influent) and treated wastewater (i.e. effluent) were collected from two wastewater treatment plants and a wastewater treatment lagoon serving municipalities in southern Ontario, Canada. In addition, grab samples of surface water were collected downstream of the lagoon discharge. After solid phase extraction (SPE) using ion-exchange columns for basic/neutral and acidic compounds, respectively, the extracts were analyzed for a suite of 16 indicator compounds. The two SPE extracts were combined for analysis of biological responses in four in vitro cell-based bioassays. The concentrations of several indicator compounds, including the estrogens, 17β-estradiol and 17α-ethinylestradiol, were below the limits of detection. However, androstenedione and estrone were detected in several influent samples. The concentrations of these steroid hormones and some of the other indicator compounds declined during treatment but acesulfame K, carbamazepine, trimethoprim and DEET persisted in the effluent. The MTS- CellTiter 96® AQueous One Solution Cell Proliferation Assay (MTS) indicated that cell viability was not affected by exposure to the extracts. The Qiagen Nuclear Receptors 10-Pathway Reporter Array indicated that several cellular pathways were upregulated, with the greatest upregulation observed with the estrogen receptor (i.e. induction ratios 12 to 47) and the liver X receptor (i.e. induction ratios 10 to 45). The ERα CALUX assay indicated that estrogenic activity was lower in effluents compared to influents, with the greatest estrogenic activity observed for grab samples of influent from the lagoon (i.e. 56-215 ng L-1 17β-estradiol equivalents). Finally, the results of the Nrf2 Luciferase Luminescence Assay indicated a lower oxidative stress in the effluent samples. Overall, the present study demonstrates that chemical analyses are limited in their ability to predict or explain reductions in the toxicity of treated wastewater. There are thus advantages to using a combination of chemical analyses and in vitro bioassays to monitor the treatment efficiency of wastewater treatment plants and to predict the potential impacts of wastewater discharges into receiving waters.


Water ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 2764
Author(s):  
Argyro Plevri ◽  
Klio Monokrousou ◽  
Christos Makropoulos ◽  
Christos Lioumis ◽  
Nikolaos Tazes ◽  
...  

Water reuse and recycling is gaining momentum as a way to improve the circularity of cities, while recognizing the central role of water within a circular economy (CE) context. However, such interventions often depend on the location of wastewater treatment plants and the treatment technologies installed in their premises, while relying on an expensive piped network to ensure that treated wastewater gets transported from the treatment plant to the point of demand. Thus, the penetration level of treated wastewater as a source of non-potable supply in dense urban environments is limited. This paper focuses on the demonstration of a sewer mining (SM) unit as a source of treated wastewater, as part of a larger and more holistic configuration that examines all three ‘streams’ associated with water in CE: water, energy and materials. The application area is the Athens Plant Nursery, in the (water stressed) city of Athens, Greece. SM technology is in fact a mobile wastewater treatment unit in containers able to extract wastewater from local sewers, treat it directly and reuse at the point of demand even in urban environments with limited space. The unit consists of a membrane bioreactor unit (MBR) and a UV disinfection unit and produces high quality reclaimed water for irrigation and also for aquifer recharge during the winter. Furthermore, a short overview of the integrated nutrient and energy recovery subsystem is presented in order to conceptualise the holistic approach and circularity of the whole configuration. The SM technology demonstrates flexibility, scalability and replicability, which are important characteristics for innovation uptake within the emerging CE context and market.


2019 ◽  
Vol 135 ◽  
pp. 01032
Author(s):  
Elena Nazimko ◽  
Sergei Malko ◽  
Anna Semenova ◽  
Vladimir Dorovskoy

The interaction of phases is at the basis of many technologies in different industries. Flotation method is used in wastewater treatment plants to capture and remove contaminants from wastewater. In this case, the interaction of air bubbles with particles of pollution with a hydrophobic surface. These interactions are very difficult to investigate because they are dynamic, subject to a large number of physical and chemical factors, and occur on a small scale. The processes mentioned above have traditionally been studied by laboratory experiments. These tests are tedious and time-consuming and show unsatisfactory accuracy. Analytical studies give idealized results. One of the most powerful alternatives for solving this problem is numerical modeling, which combines dynamics, accuracy and consideration of sophisticated details. This model is based on the discrete elements method. In this paper, a computer model for modeling the kinetics of the interaction of phases in wastewater treatment is considered.


Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1414 ◽  
Author(s):  
I-Tae Kim ◽  
Young-Seok Yoo ◽  
Young-Han Yoon ◽  
Ye-Eun Lee ◽  
Jun-Ho Jo ◽  
...  

The development of cost-effective methods, which generate minimal chemical wastewater, for methanol production is an important research goal. In this study, treated wastewater (TWW) was utilized as a culture solution for methanol production by mixed methanotroph species as an alternative to media prepared from commercial or chemical agents, e.g., nitrate mineral salts medium. Furthermore, a realistic alternative for producing methanol in wastewater treatment plants using biogas from anaerobic digestion was proposed. By culturing mixed methanotroph species with nitrate and phosphate-supplemented TWW in municipal wastewater treatment plants, this study demonstrates, for the first time, the application of biogas generated from the sludge digester of municipal wastewater treatment plants. NaCl alone inhibited methanol dehydrogenase and the addition of 40 mM formate as an electron donor increased methanol production to 6.35 mM. These results confirmed that this practical energy production method could enable cost-effective methanol production. As such, methanol produced in wastewater treatment plants can be used as an eco-friendly energy and carbon source for biological denitrification, which can be an alternative to reducing the expenses required for the waste water treatment process.


Sign in / Sign up

Export Citation Format

Share Document