scholarly journals CFD analysis of sludge accumulation and hydraulic performance of a waste stabilization pond

2012 ◽  
Vol 66 (11) ◽  
pp. 2370-2377 ◽  
Author(s):  
Andres Alvarado ◽  
Esteban Sanchez ◽  
Galo Durazno ◽  
Mehul Vesvikar ◽  
Ingmar Nopens
Keyword(s):  
Time Distribution ◽  
Tracer Experiment ◽  
Cfd Modeling ◽  
Cfd Analysis ◽  
Accumulation Rates ◽  
Waste Stabilization Ponds ◽  
Waste Stabilization Pond ◽  
Waste Stabilization ◽  
Rtd Analysis ◽  
Sludge Accumulation

Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed and three sludge accumulation scenarios based on bathymetric surveys were simulated. A residence time distribution (RTD) analysis illustrated the decrease of residence times due to sludge deposition. Sludge accumulation rates were calculated. The influence of flow pattern on the sludge deposition was studied, enabling better planning of future pond operation and desludging.

Rotavirus removal in experimental waste stabilization pond systems with different geometries and configurations

1995 ◽  
Vol 31 (12) ◽  
pp. 285-290 ◽  
Author(s):  
J. I. Oragui ◽  
H. Arridge ◽  
D. D. Mara ◽  
H. W. Pearson ◽  
S. A. Silva
Keyword(s):  
Clostridium Perfringens ◽  
Slow Process ◽  
Faecal Coliforms ◽  
Waste Stabilization Ponds ◽  
Stabilization Pond ◽  
Waste Stabilization Pond ◽  
Stabilization Ponds ◽  
Waste Stabilization

Rotavirus removal in waste stabilization ponds is a relatively slow process: in a series of ten ponds (a 1-d anaerobic pond followed by nine 2-d ponds) its numbers were reduced from 1.4 × 105 per litre to zero, and in an “innovative” series (a 1-day anaerobic pond, 3-d facultative pond, 3.8-d, 3-d and 5-d maturation ponds) from 5.1 × 104 per litre to <5 per litre. Faecal coliforms were better indicators of rotaviruses than was Clostridium perfringens .

scholarly journals Determine the Required Log Reductions of Human Intestinal Helminth Eggs by Waste Stabilization Pond: A Simulation for Wastewater Recycling in Agriculture

2019 ◽  
Vol 15 (1) ◽  
pp. 11-25
Author(s):  
Adel S. Faskol ◽  
Gabriel Racoviteanu
Keyword(s):  
Treatment Process ◽  
Hydraulic Retention Time ◽  
Climatic Conditions ◽  
Intestinal Helminth ◽  
Waste Stabilization Ponds ◽  
Waste Stabilization Pond ◽  
Helminth Eggs ◽  
Stabilization Ponds ◽  
Waste Stabilization ◽  
Wastewater Recycling

Abstract This paper investigates the determined the required log reductions for human intestinal helminth eggs by waste stabilization ponds as simulation as assessing of mitigating health risk to satisfy practice WHO, 2006 guidelines for the safe use of wastewater in agriculture (≤ 0.1 helminth egg/L) to protect the health of children under 15 years was the development of MATLAB, a computer program based waste stabilization ponds design based on parameter uncertainty and 10,000-trial Monte Carlo simulations were developed for a series of anaerobic, facultative and maturation ponds based on 95%-ile of effluent (≤ 0.1 helminth egg/L) which the result in a health-based target. Whereas the influent of the helminth eggs (Nematode) was (932.500 eggs/L). While the treatment provided (100 % reduction/removal) for the overall treatment process with total hydraulic retention time in climatic conditions of Libya it took 36.207 days in the anaerobic pond, facultative pond, first maturation pond and one of the subsequent maturation pond.

Interpretation of Laboratory-Scale Waste Stabilization Pond Studies

1987 ◽  
Vol 19 (12) ◽  
pp. 195-203 ◽  
Author(s):  
T. Wood
Keyword(s):  
Mathematical Model ◽  
Laboratory Scale ◽  
Waste Stabilization Ponds ◽  
Continuous Processes ◽  
Stabilization Pond ◽  
Waste Stabilization Pond ◽  
First Case ◽  
Waste Stabilization

The objective of this paper is to demonstrate the importance of choosing an appropriate mathematical model when analyzing the data from laboratory-scale studies of waste stabilization ponds. Two case studies are presented based on work by Thirumurthi and Nashashibi (1967) and Uhlmann et al (1983), both using semicontinuous methods of experimentation involving the addition of discrete volumes of feed at regular intervals. In both cases the authors have used mathematical models of continuous processes to analyse their results. This paper shows how semicontinuous models can be used in both studies, leading to significant differences in interpretation of the data; in the first case study this relates to the determination of rate constants and, in the second case study, to the determination of an appropriate model to describe hydraulic mixing. Each case study concludes with a discussion of the significance of the semicontinuous interpretation in the context of waste stabilization pond design.

Sludge accumulation, properties and degradation in a waste stabilization pond in Mexico

2000 ◽  
Vol 42 (10-11) ◽  
pp. 231-236 ◽  
Author(s):  
K. L. Nelson ◽  
B. C. Jiménez
Keyword(s):  
Accumulation Rate ◽  
Fecal Coliforms ◽  
Stabilization Pond ◽  
Waste Stabilization Pond ◽  
Helminth Eggs ◽  
Waste Stabilization ◽  
Sludge Accumulation

The sludge layer in a primary, facultative wastewater stabilization pond in Texcoco, Mexico was studied. Five sludge cores were taken in the pond, near the entrance, middle, exit, and at the midpoint about 5 m from each side. Each core was stratified into four subsamples and analyzed. Temperature, pH, ORP, and %VS decreased with depth (age) in the sludge layer, whereas ammonia and TS concentrations increased. The concentrations of fecal coliforms and viable helminth eggs also decreased with depth in the sludge layer, but significant concentrations of both organisms were still present in the oldest sludge, which is estimated to be over seven years old (average). From a sludge depth survey it was found that the majority of the sludge accumulated near the inlet of the pond. The average net sludge accumulation rate was estimated to be 24 mm/yr.

Acinetobacter baumannii detected on modified charcoal–cefoperazone–deoxycholate agar in a waste stabilization pond

2020 ◽  
Vol 66 (3) ◽  
pp. 206-213
Author(s):  
Maxim Sheludchenko ◽  
Anna Padovan ◽  
Mohammad Katouli ◽  
Helen Stratton
Keyword(s):  
Acinetobacter Baumannii ◽  
Selective Medium ◽  
Rrna Gene ◽  
Pathogen Removal ◽  
Waste Stabilization Ponds ◽  
Waste Stabilization Pond ◽  
Waste Stabilization ◽  
Confirmatory Tests ◽  
Wastewater Samples ◽  
The 16S Rrna Gene

Campylobacter is a recommended reference pathogen for the verification and validation of water recycling schemes in Australia and globally. In a larger study investigating the efficacy of pathogen removal in waste stabilization ponds (WSP), we cultivated bacteria from wastewater samples on modified charcoal–cefoperazone–deoxycholate agar (mCCDA) targeting the growth of Campylobacter. A high number of colonies characteristic of Campylobacter grew on this selective medium, but this did not correlate with qPCR data. Using primers targeting the 16S rRNA gene, and additional confirmatory tests to detect VS1, ompA, blaOXA-51-like, blaOXA-23-like genes, we tested 80 random colonies from 10 WSP samples. All 80 were identified as Acinetobacter baumannii. Wastewater grab samples taken three times over 6 months throughout the WSP system showed removal of A. baumannii in the WSP at rates similar to that of Escherichia coli. Our study suggests that mCCDA agar is not a suitable medium for isolating Campylobacter from environmental samples and that A. baumannii can be used as an indicator for removal of pathogens in WSPs.

Escherichia coli removal in waste stabilization ponds: a comparison of modern and classical designs

2005 ◽  
Vol 51 (12) ◽  
pp. 75-81 ◽  
Author(s):  
C.G. Banda ◽  
P.A. Sleigh ◽  
D.D. Mara
Keyword(s):  
Retention Time ◽  
Design Procedure ◽  
Waste Stabilization Ponds ◽  
E Coli ◽  
Design Procedures ◽  
Stabilization Pond ◽  
Waste Stabilization Pond ◽  
Waste Stabilization ◽  
Classical Procedure ◽  
Parameter Variations

Two PC-based waste stabilization pond design procedures, based on parameter uncertainty and 10,000-trial Monte Carlo simulations, were developed for a series of anaerobic, facultative and maturation ponds to produce ≤1000 E. coli per 100 ml for both 50% and 95% compliance. One procedure was based on the classical Marais equations and the other on the modern von Sperling equations. For the range of parameter variations selected the classical design procedure required less land area and had a shorter hydraulic retention time than the modern design procedure. For both procedures the design for 90% compliance required substantially more land and a longer retention time than the design for 50% compliance. Regulators and designers should seek a balance between system reliability (as set by the percentage compliance specified or adopted) and system costs, especially (but not only) in developing countries. It is recommended that new waste stabilization pond (WSP) systems be designed for compliance with a given E. coli effluent requirement by the classical procedure and that existing overloaded WSP systems be upgraded using the modern procedure.

Evaluation of Waste Stabilization Pond Performance in Missouri and Kansas, U.S.A.

1987 ◽  
Vol 19 (12) ◽  
pp. 39-46 ◽  
Author(s):  
Shankha K. Banerji ◽  
Brent Ruess
Keyword(s):  
Suspended Solids ◽  
Design Parameters ◽  
Waste Stabilization Ponds ◽  
Detention Time ◽  
Stabilization Pond ◽  
Loading Rates ◽  
Waste Stabilization Pond ◽  
Traditional Design ◽  
Waste Stabilization ◽  
Multiple Cells

Twenty waste stabilization ponds in Missouri and Kansas were evaluated as to their ability to meet the State effluent requirements. It was found that a large number of these ponds were violating the BOD or the suspended solids requirements on many occasions. The performance of these ponds did not correlate well with the traditional design parameters, such as BOD loading rates or mean hydraulic detention time. The use of multiple cells was also not found to be advantageous in all situations. Some of the pond design equations did not provide a valid method of estimating their performance. Effluent polishing methods are necessary to remove excess suspended solids during the critical summer months.

Sign in / Sign up

Export Citation Format

Share Document