Prediction of the O2 Conditions in the Selector

1994 ◽  
Vol 29 (7) ◽  
pp. 229-237 ◽  
Author(s):  
J. Kruit ◽  
F. Boley ◽  
L. J. A. M. Jacobs ◽  
T. W. M. Wouda
Keyword(s):  
Wastewater Treatment ◽  
Pilot Plant ◽  
Wastewater Treatment Plants ◽  
Coarse Filter ◽  
Plant Research ◽  
Influent Characterization

Influent characterization and biosorption experiments were carried out with settled influent of seven wastewater treatment plants to study the influence of O2 in the selector in relation to the success of developing good settling properties of the sludge. In previous years working selectors were installed and/or pilot plant research was carried out at these wastewater treatment plants. Characterization of the influent was done with help of standard COD and BOD measurements with help of a coarse filter. The research has elucidated that the presence of O2 in the selector, at initial sludge loadings of 3.5-6.5 kg BOD/kg MLSS.d, is important for producing good settling properties of the sludge when the sum of readily biodegradable COD and rapidly hydrolysable COD is greater than 40%. When the sum of sludge COD and slow hydrolysable COD is greater than 50% an unaerated selector can be used.

A study about the use of chemicals in conventional tertiary treatment. Performances comparison of three municipal wastewater treatment plants and pilot plant experiences

2011 ◽  
Vol 6 (1) ◽  
Author(s):  
A. Iborra-Clar ◽  
J.A. Mendoza-Roca ◽  
A. Bes-Pií ◽  
J.J. Morenilla-Martínez ◽  
I. Bernácer-Bonora ◽  
...  
Keyword(s):  
Water Quality ◽  
Wastewater Treatment ◽  
Pilot Plant ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Secondary Effluent ◽  
Municipal Wastewater Treatment ◽  
Wastewater Reclamation ◽  
Valencian Region ◽  
Municipal Wastewater Treatment Plants

Rainfall diminution in the last years has entailed water scarcity in plenty of European regions, especially in Mediterranean areas. As a consequence, regional water authorities have enhanced wastewater reclamation and reuse. Thus, the implementation of tertiary treatments has become of paramount importance in the municipal wastewater treatment plants (WWTP) of Valencian Region (Spain). Conventional tertiary treatments consist of a physico-chemical treatment of the secondary effluent followed by sand filtration and UV radiation. However, the addition of coagulants and flocculants sometimes does not contribute significantly in the final water quality. In this work, results of 20-months operation of three WWTP in Valencian Region with different tertiary treatments (two without chemicals addition and another with chemicals addition) are discussed. Besides, experiments with a 2 m3/h pilot plant located in the WWTP Quart-Benager in Valencia were performed in order to evaluate with the same secondary effluent the effect of the chemicals addition on the final water quality. Results showed that the addition of chemicals did not improve the final water quality significantly. These results were observed both comparing the three full scale plants and in the pilot plant operation.

The first sequenced Sphaerotilus natans bacteriophage– characterization and potential to control its filamentous bacterium host

2021 ◽  
Vol 97 (4) ◽  
Author(s):  
Rute Ferreira ◽  
Rui Amado ◽  
Jorge Padrão ◽  
Vânia Ferreira ◽  
Nicolina M Dias ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Bacterial Communities ◽  
Potential Application ◽  
Deleterious Effect ◽  
Wastewater Treatment Plants ◽  
Lytic Phage ◽  
Filamentous Bacterium ◽  
Sphaerotilus Natans ◽  
Isolation And Characterization

ABSTRACT Bacteriophages (phages) are ubiquitous entities present in every conceivable habitat as a result of their bacterial parasitism. Their prevalence and impact in the ecology of bacterial communities and their ability to control pathogens make their characterization essential, particularly of new phages, improving knowledge and potential application. The isolation and characterization of a new lytic phage against Sphaerotilus natans strain DSM 6575, named vB_SnaP-R1 (SnaR1), is here described. Besides being the first sequenced genome of a Sphaerotilus natans infecting phage, 99% of its 41507 bp genome lacks homology with any other sequenced phage, revealing its uniqueness and previous lack of knowledge. Moreover, SnaR1 is the first Podoviridae phage described infecting this bacterium. Sphaerotilus natans is an important filamentous bacterium due to its deleterious effect on wastewater treatment plants (WWTP) and thus, phages may play a role as novel biotechnological tools against filamentous overgrowth in WWTP. The lytic spectrum of SnaR1 was restricted to its host strain, infecting only one out of three S. natans strains and infection assays revealed its ability to reduce bacterial loads. Results suggest SnaR1 as the prototype of a new phage genus and demonstrates its potential as a non-chemical alternative to reduce S. natans DSM 6575 cells.

Detection and molecular characterization of enteric adenovirus in treated wastewater in the Brazilian Federal District

2021 ◽  
Vol 3 (7) ◽  
Author(s):  
T. S. C. Quintão ◽  
F. G. Silva ◽  
A. L. Pereira ◽  
W. N. Araújo ◽  
P. M. Oliveira ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Federal District ◽  
Treated Wastewater ◽  
Conventional Pcr ◽  
Rainfall Index ◽  
Enteric Adenovirus ◽  
Enteric Adenoviruses

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.

Estimation of Kinetic Parameters of Heterotrophic Biomass under Aerobic Conditions and Characterization of Wastewater for Activated Sludge Modelling

1992 ◽  
Vol 25 (6) ◽  
pp. 125-139 ◽  
Author(s):  
J. Kappeler ◽  
W. Gujer
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Kinetic Parameters ◽  
Specific Growth ◽  
Wastewater Treatment Plants ◽  
Simple Method ◽  
Batch Tests ◽  
Different Types ◽  
Heterotrophic Biomass

To predict the behaviour of biological wastewater treatment plants, the Activated Sludge Model No. 1 is often used. For the application of this model kinetic parameters and wastewater composition must be known. A simple method to estimate kinetic parameters of heterotrophic biomass and COD wastewater fractions is presented. With three different types of batch-tests these parameters and fractions can be determined by measuring oxygen respiration. Our measurements showed that the maximum specific growth rate µmax of heterotrophic biomass depends on temperature, reactor configuration and SRT. In typical wastewater treatment plants of Switzerland the amount of readily biodegradable substrate was generally small (about 9 % of the COD in primary effluent). The same method can also be used to determine kinetic parameters of nitrifying biomass.

Characterization of Sewage Sludge of Wastewater Treatment Plants in Alexandria

2003 ◽  
Vol 33 (3) ◽  
pp. 529-542
Author(s):  
Olfat El-Sebaie ◽  
Ahmed Hussein ◽  
Mohamed Ramadan ◽  
Magda Abd El-Atty ◽  
Helaly Helaly
Keyword(s):  
Wastewater Treatment ◽  
Sewage Sludge ◽  
Wastewater Treatment Plants

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%.

Biofilm characterization of several wastewater treatment plants with rotating biological contactors in Madrid (Spain)

1998 ◽  
Vol 37 (4-5) ◽  
pp. 215-218 ◽  
Author(s):  
B. Pérez-Uz ◽  
C. Franco ◽  
M. Martín-Cereceda ◽  
L. Arregui ◽  
I. Campos ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Species Composition ◽  
Wastewater Treatment Plants ◽  
Species Level ◽  
Plant Performance ◽  
Ciliate Species ◽  
Level Ii ◽  
Rotating Biological Contactors ◽  
One Year

Ciliate communities were studied in the biofilms of three plants with rotating biological contactors (RBCs) over the period of one year. The aims of this study were: (i) to characterize ciliates to species level; (ii) to determine their abundance and spatial variation through the biological system; and (iii) to relate the spatial segregation and richness of ciliate species to plant performance. A number of species ranging from 33 to 67 were identified at the different plants. The overall best represented groups were peritrichs followed by scuticociliates (Las Matas), cyrtophorids (Boadilla) or hypotrichs (Camarma). Comparison of RBCs and activated sludge communities indicated that even though both were mainly constituted by peritrichs, differences in groups and species composition were observed.

scholarly journals Preparation and characterization of activated carbon from sewage sludge: carbonization step

2004 ◽  
Vol 49 (1) ◽  
pp. 139-146 ◽  
Author(s):  
S. Rio ◽  
C. Faur-Brasquet ◽  
L. Le Coq ◽  
D. Lecomte ◽  
P. Le Cloirec
Keyword(s):  
Wastewater Treatment ◽  
Activated Carbon ◽  
Sewage Sludge ◽  
Thermal Treatment ◽  
Wastewater Treatment Plants ◽  
Carbonization Temperature ◽  
Carbon Production ◽  
By Products ◽  
Characterization Of Activated Carbon

Sewage sludges produced from wastewater treatment plants continue to create environmental problems in terms of volume and method of valorization. Thermal treatment of sewage sludge is considered as an attractive method in reducing sludge volume which at the same time produces reusable by-products. This paper deals with the first step of activated carbon production from sewage sludge, the carbonization step. Experiments are carried out on viscous liquid sludge and limed sludge by varying carbonization temperature and heating rate. The results show that carbonized residue properties are interesting for activated carbon production.

OPTIMISATION OF W ASTEW A TER TREATMENT PLANTS BY MEANS OF COMPUTER MODELS

1994 ◽  
Vol 30 (4) ◽  
pp. 181-190 ◽  
Author(s):  
René Dupont ◽  
Ole Sinkjær
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Pilot Plant ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Operational Strategies ◽  
Nitrification Process ◽  
Computer Based ◽  
Calibration Tool ◽  
Denitrification Process

The objective of the work presented is to demonstrate how computer based models can be used to improve the effluent quality from wastewater treatment plants by optimisation of the operation. The investigation was carried out in connection with pilot plant investigations at Damhusllen Wastewater Treatment Plant in order to establish the design basis for upgrading the treatment plants in the city of Copenhagen. Calibration of the model was done with thorough characterisation of the wastewater and the activated sludge as the primary calibration tool. Special attention was paid to the nitrification process, which by previous investigations was shown to be occasionally inhibited. Model constants for the nitrification process were detennined from experiments. Default constants were used for nearly all other constants. The pilot plant was optimized with the calibrated model. Different operational strategies for improvement of the denitrification process were tested. The denitrification process was operated relatively poorly at the time for the optimisation. The calibration showed that it was possible to calibrate the model using the characterization of the wastewater and the activated sludge as the primary calibration tool. Further it was shown that the calihrated model could be used as a tool for optimising the operation of the pilot plant. The suggested operation correlated well with the practical realisable operation.

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