Determining potential indicators of Cryptosporidium oocysts throughout the wastewater treatment process

2012 ◽  
Vol 65 (5) ◽  
pp. 875-882 ◽  
Author(s):  
H.-W. A. Cheng ◽  
M. A. Broaders ◽  
F. E. Lucy ◽  
S. E. Mastitsky ◽  
T. K. Graczyk
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Treatment Process ◽  
Giardia Duodenalis ◽  
Strong Positive Correlation ◽  
Indicator Organisms ◽  
Microbial Indicators ◽  
Cryptosporidium Oocysts ◽  
Giardia Cysts

Most research on wastewater treatment efficiency compliance focuses on physicochemical and microbial indicators; however, very little emphasis has been placed so far on determining suitable indicator organisms to predict the discharge level of pathogens from treatment plants. In this study, raw wastewater, activated sludge, and the resulting final effluents and biosolids in four municipal wastewater treatment plants (WWTPs A, B, C and D) were seasonally investigated for human-virulent water-borne pathogens Cryptosporidium parvum/hominis and Giardia duodenalis, and microsporidia (e.g. Encephalitozoon hellem, E. intestinalis, and Enterocytozoon bieneusi) between 2008 and 2009. A suite of potential microbial indicators for human-virulent protozoa and microsporidia was also determined. A combination of multiple fluorescent in situ hybridization and immunofluorescent antibody assays were applied to detect Cryptosporidium oocysts, Giardia cysts, and microsporidian spores. Escherichia coli, enterococci and Clostridium perfringens spores were cultivated in selective media. Positive correlations were found between the abundance of enterococci and E. coli and abundance of Cryptosporidium oocysts (rs > 0.47, p < 0.01) and Giardia cysts (rs > 0.44, p < 0.01) at WWTPs A–D. Cryptosporidium perfringens spores were positively correlated to Cryptosporidium oocysts (rs = 0.40, p < 0.01) and Giardia cysts (rs = 0.46, p < 0.01). There was a strong positive correlation between abundance of Giardia cysts and that of Cryptosporidium oocysts (rs > 0.89, p < 0.01). To sum up, a suite of faecal indicator bacteria can be used as indicators for the presence of Cryptosporidium oocysts and Giardia cysts in these activated-sludge systems (WWTPs A, B and C). Overall, Giardia duodenalis was noted to be the best Cryptosporidium indicator for human health in the community-based influent wastewater and throughout the treatment process.

Impact of a wastewater treatment plant on Cryptosporidium oocysts and Giardia cysts occurring in a surface water

2000 ◽  
Vol 41 (7) ◽  
pp. 31-37 ◽  
Author(s):  
E. Carraro ◽  
E. Fea ◽  
S. Salva ◽  
G. Gilli
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Municipal Wastewater Treatment ◽  
Mean Values ◽  
Cryptosporidium Oocysts ◽  
The Impact ◽  
Receiving Water ◽  
Giardia Cysts

The aim of this study was to assess the impact of a municipal wastewater treatment plant (MWTP) on the occurrence of Cryptosporidium oocysts and Giardia cysts in the receiving water. All MWTP effluent samples were Giardia and Cryptosporidium contaminated, although low mean values were found for both parasites (0.21±0.06 oocysts/L; 1.39±0.51 cysts/L). Otherwise, in the raw sewage a greater concentration was detected (4.5±0.3 oocysts/L; 53.6±6.8 cysts/L). The major occurrence of Giardia over Cryptosporidium, both in the influent and in the effluent of the MWTP, is probably related to the human sewage contribution to the wastewater. Data on protozoa contamination of the receiving water body demonstrated similar concentrations in the samples collected before (0.21±0.07 oocysts/L; 1.31±0.38 cysts/L) and after (0.17±0.09 oocysts/L and 1.01±1.05 cysts/L) the plant effluent discharge. The results of this study suggest that the MWTP has no impact related to Giardia and Cryptosporidium river water contamination, and underline the need for investigation into the effectiveness of these protozoa removal by less technologically advanced MWTPs which are the most widespread and could probably show a lower ability to reduce protozoa.

Comparison of F-specific bacteriophage, enterococci, and faecal coliform densities through a wastewater treatment process employing oxidation ponds

1995 ◽  
Vol 31 (5-6) ◽  
pp. 85-89 ◽  
Author(s):  
S. J. Turner ◽  
G. D. Lewis
Keyword(s):  
Wastewater Treatment ◽  
Treatment Process ◽  
Faecal Coliform ◽  
Indicator Organisms ◽  
Faecal Coliforms ◽  
Wastewater Treatment Process ◽  
Oxidation Pond ◽  
Oxidation Ponds ◽  
Specific Bacteriophage

Over a 12 month period F-specific bacteriophages, faecal coliforms and enterococci were compared as microbial indicator organisms for the quality of a wastewater treatment (oxidation pond) system. Results suggest that enterococci may be the most useful indicator for oxidation pond systems.

Municipal wastewater treatment in Berlin with deep tanks and flotation for secondary clarification

1996 ◽  
Vol 33 (12) ◽  
pp. 199-210
Author(s):  
R. Gnirss ◽  
A. Peter-Fröhlich ◽  
V. Schmidt
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Energy Requirements ◽  
Municipal Wastewater Treatment ◽  
Space Saving ◽  
Process Energy ◽  
Near Future ◽  
Interesting Alternative ◽  
Pilot Tests

For municipal wastewater treatment, space-saving 10m deep activated sludge tanks are an interesting alternative to conventional tanks of shallow construction. Results from pilot tests in the Berlin-Ruhleben WWTP have shown that the biological P-elimination, nutrification and denitrification processes can be implemented as in shallow tanks. However, the activated sludge did not settle satisfactorily. Flotation was implemented in the process for secondary clarification and in the meanwhile has shown to be advantageous. Tests run over a period of some years with the pilot plant have proven the feasibility of this process. Energy requirements for both systems were found to be approximately the same. A cost estimate based on a preplan revealed a 10% advantage in favour of the 10m WWTP with flotation. For these reasons, one 10m WWTP with flotation for secondary clarification and a capacity of 80,000 m3/d will be built in Berlin in the near future.

Floc size distribution and bacterial activities in membrane separation activated sludge processes for small-scale wastewater treatment/reclamation

1997 ◽  
Vol 35 (6) ◽  
pp. 37-44 ◽  
Author(s):  
Boran Zhang ◽  
Kazuo Yamamoto ◽  
Shinichiro Ohgaki ◽  
Naoyuki Kamiko
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Membrane Separation ◽  
Small Scale ◽  
Nitrification Rate ◽  
Floc Size ◽  
Denitrification Activity ◽  
Concentration Changes ◽  
Activated Sludge Processes

Activated sludges taken from full-scale membrane separation processes, building wastewater reuse system (400m3/d), and two nightsoil treatment plants (50m3/d) as well as laboratory scale membrane separation bioreactor (0.062m3/d) were analyzed to characterize membrane separation activated sludge processes (MSAS). They were also compared with conventional activated sludges(CAS) taken from municipal wastewater treatment plants. Specific nitrification activity in MSAS processes averaged at 2.28gNH4-N/kgMLSS.h were higher than that in CAS processes averaged at 0.96gNH4-N/kgMLSS.h. The denitrification activity in both processes were in the range of 0.62-3.2gNO3-N/kgMLSS.h without organic addition and in the range of 4.25-6.4gNO3-N/kgMLSS.h with organic addition. The organic removal activity in nightsoil treatment process averaged at 123gCOD/kgMLSS.h which was significantly higher than others. Floc size distributions were measured by particle sedimentation technique and image analysis technique. Flocs in MSAS processes changed their sizes with MLSS concentration changes and were concentrated at small sizes at low MLSS concentration, mostly less than 60 μm. On the contrary, floc sizes in CAS processes have not much changed with MLSS concentration changes and they were distributed in large range. In addition, the effects of floc size on specific nitrification rate, denitrification rate with and without organic carbon addition were investigated. Specific nitrification rate was decreased as floc size increased. However, little effect of floc size on denitrification activity was observed.

PARAMETERS FOR DYNAMIC SIMULATION OF W ASTEW ATER TREATMENT PLANTS WITH HIGH-RATE AND LOW-RATE ACTIVATED SLUDGE TANKS

1994 ◽  
Vol 30 (4) ◽  
pp. 211-214 ◽  
Author(s):  
E. Brands ◽  
M. Liebeskind ◽  
M. Dohmann
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Dynamic Simulation ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
High Rate ◽  
Yield Coefficient ◽  
Municipal Wastewater Treatment ◽  
Municipal Wastewater Treatment Plants ◽  
Low Rate

This study shows a comparison of important parameters for dynamic simulation concerning the highrate and low-rate activated sludge tanks of several municipal wastewater treatment plants. The parameters for the dynamic simulation of the single-stage process are quite well known, but parameters for the high-ratellow-rate activated sludge process are still missi ng, although a considerable number of wastewater treatment plants are designed and operated that way. At present any attempt to simulate their operation is restricted to the second stage due to missing data concerning growth rate, decay rate, yield coefficient and others.

Characterization of wastewater and activated sludge from European municipal wastewater treatment plants using the NUR test

1998 ◽  
Vol 38 (1) ◽  
pp. 303-310 ◽  
Author(s):  
V. Naidoo ◽  
V. Urbain ◽  
C. A. Buckley
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Municipal Wastewater Treatment ◽  
Batch Tests ◽  
Denitrification Kinetics ◽  
Municipal Wastewater Treatment Plants

Denitrification kinetics and wastewater characterization of eight different plants in Europe are discussed. Denitrification batch tests revealed three distinct rates except in the cases of Plaisir, Rostock and Orense where 4 rates were observed. The latter three plants revealed atypical rapid initial rates which were between 7 and 21 mgN/gVSS.h. All denitrification kinetics under non-limiting carbon conditions revealed fast first rates which ranged between 3.0 and 7.3 mgN/gVSS.h. Acetate was used to simulate denitrification kinetics with readily biodegradable COD present. Two subsequent rates were observed. Rates 2 and 3 ranged between 2 and 3 mgN/gVSS.h, and 1 and 2 mgN/gVSS.h, respectively. The RBCOD fraction varied between 10 and 19%, except for one of the plants where the value determined was 7%.

scholarly journals Sensitivity analysis of a municipal wastewater treatment plant model

2019 ◽  
Vol 252 ◽  
pp. 05010
Author(s):  
Paweł Król ◽  
Alberto Gallina ◽  
Michał Lubieniecki ◽  
Tadeusz Uhl ◽  
Tadeusz Żaba
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Treatment Process ◽  
Biological Process ◽  
Treatment Plant ◽  
Numerical Procedure ◽  
Municipal Wastewater Treatment ◽  
Wastewater Treatment Process ◽  
Plant Model ◽  
The Relationship

Waste management is a crucial process to keep the environment in wholesome conditions. The environmental impact of solid waste and wastewater is reduced through construction of appropriate disposal installations. The objective of wastewater treatment in biological reactors is to control the process of biomaterial growth by aerating the sewage content. The process is complex, as depending on a plenty of parameters. In the last decades an effective numerical model, called the Activated Sludge Model (ASM), has been proposed for describing the biological process. The ASM is implemented in the Benchmark Simulation Model (BSM) that simulates the whole wastewater treatment process. The most important parameters in ASM are the kinetic and stoichiometric coefficients. The former describes rate-concentration dependence. The latter characterises the relationship between the components of chemical reactions taking place in the cleaning process. Above parameters are determined by on-site calibration and their importance is relevant during the development of numeric models. This paper aims to examine the influence of kinetic and stoichiometric parameters on the wastewater treatment process of a plant in Płaszów, Kraków. The analysis is carried out by a sample-based numerical procedure. It highlights the ASM parameters playing a major role in the treatment process. Results obtained from the analysis are important for future validation and optimisation processes.

scholarly journals Unravelling diversity and metabolic potential of microbial consortia at each stage of leather sewage treatment

RSC Advances ◽  
2017 ◽  
Vol 7 (66) ◽  
pp. 41727-41737 ◽  
Author(s):  
Hebin Liang ◽  
Dongdong Ye ◽  
Lixin Luo
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Treatment Process ◽  
Sewage Treatment ◽  
Microbial Consortia ◽  
Biological Wastewater Treatment ◽  
Metabolic Potential ◽  
Ecological Functions ◽  
Wastewater Treatment Process ◽  
System P

Activated sludge is essential for the biological wastewater treatment process and the identification of active microbes enlarges awareness of their ecological functions in this system.

Sign in / Sign up

Export Citation Format

Share Document