Inactivation of Salmonella spp. from secondary and tertiary effluents by UV irradiation

2003 ◽  
Vol 47 (3) ◽  
pp. 147-150 ◽  
Author(s):  
R. Keller ◽  
F. Passamani ◽  
L. Vaz ◽  
S.T. Cassini ◽  
R.F. Gonçalves
Keyword(s):  
Uv Irradiation ◽  
Batch Reactor ◽  
Treatment Plant ◽  
Treated Wastewater ◽  
Uasb Reactor ◽  
Clinical Samples ◽  
Salmonella Spp ◽  
Biofilm Reactors ◽  
Scale Reactor ◽  
Real Scale

The aim of this study was to verify the efficiency of UV irradiation in the inactivation of Salmonella spp. in treated wastewater with different levels of turbidity and exposed to increasing doses of UV irradiation. Experiments were carried out in a batch reactor and in a real scale reactor. Salmonellae obtained from clinical samples were seeded into autoclaved wastewater collected from a wastewater treatment plant (WWTP) comprising an association of a UASB reactor followed by three submerged aerated biofilters (BAF) and one tertiary filter. The results showed that salmonellae were not inactivated in effluents from the UASB reactor indicating that the presence of suspended solids was an important obstacle to UV penetration in bacteria. However, UV irradiation was efficient in inactivating Salmonella of effluents from aerated secondary and tertiary biofilm reactors.

Pathogen removal efficiency from UASB + BF effluent using conventional and UV post-treatment systems

2004 ◽  
Vol 50 (1) ◽  
pp. 1-6 ◽  
Author(s):  
R. Keller ◽  
R.F. Passamani-Franca ◽  
F. Passamani ◽  
L. Vaz ◽  
S.T. Cassini ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Uv Irradiation ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Uasb Reactor ◽  
Salmonella Spp ◽  
E Coli ◽  
Helminth Eggs ◽  
Uv Reactor ◽  
Thermotolerant Coliforms

The aim of this study was to verify the efficiency of removal of microorganisms in effluents of a Wastewater Treatment Plant (WWTP) comprising an association of a UASB reactor followed by three submerged aerated biofilters (BAF) and one tertiary filter. The WWTP designed to treat domestic wastewater from a population of 1,000 inhabitants showed high removal efficiency for organic matter and suspended solids. Helminth eggs were also efficiently removed from the tertiary effluent and were found in the sludge from the UASB reactor; however, removal of bacteria in this system was very low. To enhance the efficiency of the system, the effluent from tertiary filters was submitted to UV disinfection in a real scale reactor. Our results showed that UV irradiation was very effective at lowering the concentrations of E. coli, thermotolerant coliforms and coliphages to acceptable levels for agricultural reuse. Salmonella spp. and helminth eggs were seeded into the tertiary effluent before passing through the UV reactor. Salmonella was not found in the final effluent, but helminth eggs were not completely inactivated by UV irradiation and viable eggs were detected after 28 d of incubation.

UV-disinfection of treated wastewater: possible effects on surface waters

1994 ◽  
Vol 29 (12) ◽  
pp. 255-266 ◽  
Author(s):  
T. Gschlößl
Keyword(s):  
Uv Irradiation ◽  
Wastewater Treatment Plants ◽  
Technological Development ◽  
Research Work ◽  
Treatment Plant ◽  
Pilot Project ◽  
Point Sources ◽  
Treated Wastewater ◽  
Bathing Water Directive ◽  
Flowing Waters

UV-irradiation as an effective method of diminishing germs in the outlet of wastewater treatment plants was studied in a half-scale pilot-project sponsored by the State of Bavaria/BRD for a period of 3 years. Technical, physical and biological parameters capable of influencing this process were examined. The possibility to improve the hygienic and also the ecological structure of receiving waters was put to discussion. Possible effects of formed bypproducts upon the water biocoenosis of rivers were pointed out. The results demonstrated that UV-irradiation can diminish the number of germs in the outlet of a treatment plant to an extent which is sufficient to guarantee the maintenance of the bacteriological and presumably also the virological values set by the EC Bathing Water Directive. Nevertheless the UV-treatment process requires further technological development and research work concerning i.e. the improvement of hydraulic conditions, coat-forming on the quartz sleeves of the lamps, photochemical forming of by-products, after-growth and effects upon the localised benthic flora and fauna of the receiving water. It has to be stressed that a significant improvement of the bacteriological structure of flowing waters is only attainable, if the influx from non-point sources can be reduced simultaneously.

A pilot scale study of a sequencing batch reactor treating municipal wastewater operated via the UP-PND process

2008 ◽  
Vol 58 (2) ◽  
pp. 435-438 ◽  
Author(s):  
M. Kornaros ◽  
C. Marazioti ◽  
G. Lyberatos
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Treated Wastewater ◽  
Synthetic Wastewater ◽  
Second Step ◽  
Decentralized Wastewater Treatment ◽  
Real Wastewater

SBRs are usually preferred as small and decentralized wastewater treatment systems. We have demonstrated previously that using a frequent enough switching between aerobic and anoxic conditions and a specific to the treated wastewater aerobic to anoxic phase ratio, it is possible to by-pass the second step of nitrification (i.e. conversion of nitrite to nitrate nitrogen). This innovative process for nitrate by-pass has been branded as UP-PND (University of Patras-Partial Nitrification Denitrification) (WO 2006/129132). The proved methodology was successfully transferred from a lab-scale SBR reactor treating synthetic wastewater to a pilot-scale SBR system treating real wastewater. In this work we present the results from the operation of this pilot-scale SBR, constructed in the Wastewater Treatment Plant of Patras (Greece), using 6-hour, 8-hour and 12-hour cycles. It is demonstrated that three pairs of aerobic/anoxic phases with a relative duration of 1:2 (8-hour cycle) and 2:3 (12-hour cycle) secures the desired by-pass of nitrate production.

scholarly journals Detection of Enteric Viruses and Bacterial Indicators in a Sewage Treatment Center and Shallow Water Bay

2020 ◽  
Vol 17 (18) ◽  
pp. 6483
Author(s):  
Essam M. Janahi ◽  
Sakina Mustafa ◽  
Saba F. D. Parkar ◽  
Humood A. Naser ◽  
Zaki M. Eisa
Keyword(s):  
Public Health ◽  
Hepatitis A Virus ◽  
Treatment Plant ◽  
Enteric Viruses ◽  
Treated Wastewater ◽  
Treatment Center ◽  
High Concentration ◽  
Salmonella Spp ◽  
Detection Rates ◽  
E Coli

The incidence of enteric viruses in treated wastewater and their potential release into the environment or use for agriculture are very critical matters in public health. In our study, PCR (polymerase chain reaction) analysis of enteric viruses was performed on 59 samples of influents and effluents collected from Tubli wastewater treatment plant (Water Pollution Control Center (WPCC)) and Tubli Bay, where the effluents were discharged, in Kingdom of Bahrain during two sampling periods. Four clinically essential waterborne enteric viruses were examined: enterovirus (EV), hepatitis A virus (HAV), astroviruses (AV), and rotaviruses (RV) and compared to standard bacterial and bacteriophages indicators of fecal pollution. Detection rates of EV, AV, HAV, and RV in the influent samples were 100%, 75%, 12.5%, and 12.5%, respectively, while 50% of the effluent samples from Tubli WPCC contained only EV RNA. None of the tested enteric viruses could be detected in any of the samples collected directly from Tubli Bay. Effluent samples from Tubli plant did not show significant seasonal differences. Since detection of enteric viruses genome does not necessarily indicate infectivity, the infectivity of these viruses was evaluated through isolation and growth of indictor bacteria and bacteriophages. High concentration of fecal bacteriological indicators was detected in all effluents samples (100%): 3.20 × 103 cfu/mL for E. coli, 1.32 × 103 cfu/mL for Salmonella spp., and 1.92 × 103 cfu/mL for Shigella spp. E. coli and Salmonella specific bacteriophages were also detected in the effluent samples in high titers. The combined results of PCR and bacterial enumeration point to a probable public health risk via the use of these wastewaters in agriculture or their discharge into the sea. Continuous surveillance of viral and bacterial prevalence and their resistance to sewage disinfection procedures could contribute to a better control of risks associated with the recycling of effluent wastewater and its release into the environment.

Ammonia and phosphorus removal in polishing ponds: a case study in Southeast Brazil

2007 ◽  
Vol 55 (11) ◽  
pp. 65-71 ◽  
Author(s):  
R.K.X. Bastos ◽  
E.N. Rios ◽  
F.L. Dornelas ◽  
F.A.L. Assunção ◽  
L.E. Nascimento
Keyword(s):  
Experimental Data ◽  
Wastewater Treatment ◽  
Phosphorus Removal ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Ammonia Removal ◽  
Uasb Reactor ◽  
Shallow Ponds ◽  
Real Scale

Ammonia and phosphorus removal were evaluated over four years monitoring of an experimental wastewater treatment plant in Brazil: initially a UASB reactor (real scale) + three shallow polishing ponds (pilot scale), afterwards a UASB + submerged aerated biofilter (BF) (real scale) + the same pond series. Shallow ponds (h < 0.90m) provided considerable ammonia removal, but phosphorus removal was somewhat poorer. An equation was derived for the estimation of ammonia pond effluent, based on the same assumptions of the well known Pano and Middlebrooks model. According to the experimental data, an effluent suitable for aquaculture should be achieved with retention time of 25 days.

Sewage reuse for aquaculture after treatment in oxidation and duckweed pond

2007 ◽  
Vol 55 (11) ◽  
pp. 173-181 ◽  
Author(s):  
M.M. Ghangrekar ◽  
N. Kishor ◽  
A. Mitra
Keyword(s):  
Operating Cost ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Full Scale ◽  
Treated Wastewater ◽  
Uasb Reactor ◽  
Oxidation Pond ◽  
Treated Sewage ◽  
Natural Treatment ◽  
Duckweed Pond

The benefits of treating sewage by pond systems offer, through a simple and low-cost technology, social and commercial benefits, from the waste raw materials. The objective of this work was to demonstrate an effective treatment of the sewage by using natural treatment systems, and use of treated wastewater for aquaculture. The study was conducted for the sewage generated from the IIT Kharagpur campus. After characterization of the sewage, laboratory scale experiments were conducted for treatment using oxidation pond and duckweed pond. Survival and growth of fishes were observed in the experimental ponds using treated sewage. Based on the experimental results, full-scale treatment plant was designed to meet the aquaculture water quality. From the economics of the proposed full-scale plant, and utilization of the treated sewage for aquaculture, it is estimated that, the amount of Rs. 20,0000 can be generated every year. This amount recovered from the aquaculture will be more than the operating cost of the treatment plant, hence, making the operation of sewage treatment plant self sufficient. Use of a UASB reactor as the first stage treatment before sewage passes to the oxidation pond, can be a more attractive alternative because of less land requirement as compared to the oxidation pond alone, and additional land can be made available for aquaculture to increase revenue.

Wastewater treatment from a motor-oil reforming company using a sequencing batch reactor (SBR)

2003 ◽  
Vol 47 (10) ◽  
pp. 25-32
Author(s):  
P. Drillia ◽  
M. Kornaros ◽  
G. Lyberatos
Keyword(s):  
Wastewater Treatment ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Treatment Plant ◽  
Ceramic Membranes ◽  
Treated Wastewater ◽  
Organic Load ◽  
Motor Oil ◽  
Pre Treatment ◽  
Open Trench

The main aim of this work was to study the ability of an aerobically operated sequencing batch reactor (SBR) to effectively treat the wastewaters produced by a motor-oil reforming company. In fact, the most important goal was to substantially reduce the organic load of these wastewaters before their disposal to an open trench, since the currently installed wastewater treatment plant, that includes an API separator followed by physico-chemical pre-treatment and an oxidation ditch, has proved today to be completely inefficient. The wastewater to be treated was mainly composed of five different streams from various points of the motor-oil reforming plant (e.g. gas washing tanks, cooling pumps, used motor oils holding tanks, etc). The major problem faced in this work was the high organic load (about 12,000 mg COD/L) and the free and dissolved oil contained in the wastewater (around 6-7%). Moreover, two of the streams, contributing to the mixed wastewater up to 30%, were unable to sustain dissolved oxygen and unfortunately their mixing with the other three streams resulted in the same detrimental effect. Therefore, experiments were conducted using either three or all of the contributing streams. The mixed wastewater was fed to the reactor either untreated or pre-treated with ceramic membranes in order to exclude all the free and dissolved oil. The application of pre-treated wastewater with membranes to the SBR system resulted in 75.2% and 81.9% total and dissolved COD reduction, respectively.

scholarly journals Evaluation of pathogen risks using QMRA to explore wastewater reuse options: A case study from New Delhi in India

2020 ◽  
Author(s):  
Rajashree Hajare ◽  
Pawan Labhasetwar ◽  
Pranav Nagarnaik
Keyword(s):  
Water Quality ◽  
Water Reuse ◽  
Treatment Plant ◽  
Control Measures ◽  
Effluent Treatment ◽  
Treated Wastewater ◽  
Quantitative Microbial Risk Assessment ◽  
Salmonella Spp ◽  
Cryptosporidium Spp ◽  
Reuse Options

Abstract Selecting appropriate reuse for treated wastewater is a challenge. The current investigation outlines the utilization of quantitative microbial risk assessment (QMRA) to assist Effluent Treatment Plant (ETP) management to determine the best-possible reuse of treated wastewater from 11 ETPs in Delhi. Four representative pathogens: pathogenic E.coli spp., Salmonella spp., Cryptosporidium spp. and Giardia spp. were selected to characterize microbial water quality. Reuse options selected based on the survey and interaction with ETP managers include crop-irrigation, garden-irrigation, toilet-flush and industrial applications. The probability-of-infection was characterized for two exposure groups: workers and children. Water quality monitoring indicates the occurrence of pathogenic E.coli spp (100%), Salmonella spp.(63%), Cryptosporidium spp. (81%) and Giardia spp. (45%) in the treated wastewater. QMRA reveals the annual median-probability of infection above acceptable limits for pathogenic E.coli spp., Cryptosporidium spp. and Salmonella spp. The probabilities of Giardia-associated infections were low. Adults showed a 1.24 times higher probability of infection compared to children. Sensitivity analysis indicated pathogen concentration as the most critical factor. The study highlights that the existing plans for chlorination-based treatment technology may prove insufficient in reducing the risk for selected reuse options; but, alternate on-site control measures and up-grading water reuse protocol may be effective.

Research on Aerobic Granular Sludge Cultivated under Selective Pressure

2014 ◽  
Vol 1004-1005 ◽  
pp. 908-913
Author(s):  
Qing Zhao ◽  
Qi Xia Liu ◽  
Xin Zou
Keyword(s):  
Selective Pressure ◽  
Batch Reactor ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
Uasb Reactor ◽  
Municipal Sewage ◽  
Carbon Substrate ◽  
Aerobic Sludge

Inoculated with aerobic sludge from the UASB reactor of a pharmaceutical plant and excess sludge of a municipal sewage treatment plant, granulation of aerobic sludge was realized in a sequencing batch reactor fed with glucose as carbon substrate. Selective pressure created by means of increasing organic loading and decreasing sedimentation time enhances the formation of aerobic granular sludge. Granules started to appear after 35 days operation. The granules were composed of filamentous species with varying degrees of rod-and coccal-type bacteria. While COD and NH4+-N of influent retaining 1600mg/l and 160mg/l, COD and NH4+-N of effluent respectively were 40mg/l and 1mg/l. The removal rates were higher than 95% and 99%.

scholarly journals Microbial Quality of Treated Wastewater and Borehole Water Used for Irrigation in a Semi-Arid Area

2021 ◽  
Vol 18 (16) ◽  
pp. 8861
Author(s):  
Pholosho Mmmateko Kgopa ◽  
Phatu William Mashela ◽  
Alen Manyevere
Keyword(s):  
Treatment Plant ◽  
Post Treatment ◽  
Limpopo Province ◽  
Interactive Effects ◽  
Treated Wastewater ◽  
Microbial Quality ◽  
Salmonella Spp ◽  
Borehole Water ◽  
The University

The current study investigated the distribution of microbial populations and diversity in treated wastewater used for irrigation at the University of Limpopo Experimental Farm (ULEF), from different stages of post treatment disposal at Mankweng Wastewater Treatment Plant (MWTP) in Limpopo Province, South Africa. The study was arranged in a 4 × 5 factorial experiment, which studied the interactive effects of four collection points and five months of sampling, with borehole water used as a reference point. Water samples were analyzed for bacteria, helminths, and protozoa. All data were transformed and subjected to factorial analysis of variance. The site–time interactions were significant for Salmonella spp. and Ascaris lumbricoides, whereas collection point was significant for all variables. In conclusion, movement and storage of water post treatment at MWTP were able to improve the microbial quality of the treated wastewater disposed for irrigation at ULEF.

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