scholarly journals Hydrodynamic and water quality modelling of Southern Evoikos Gulf, Greece

2013 ◽  
Vol 1 (2) ◽  
pp. 131-141
Keyword(s):  
Water Quality ◽  
Biological Treatment ◽  
Sewage Treatment ◽  
Water Quality Modelling ◽  
Sewage Treatment Plants ◽  
N Removal ◽  
Limiting Nutrient ◽  
Total Capacity ◽  
P Removal

A mathematical model is presented, consisting of a two-layer, finite difference hydrodynamic submodel and a compartmental water quality sub-model. The model is calibrated with field data. Then, it is applied to Southern Evoikos Gulf, an open coastal water body of particular ecological significance in the region of Attiki, in Greece. The application of the model aims at assessing the effect of three alternative treatment scenarios (i.e. biological treatment, biological treatment with N removal and biological treatment with N and P removal) performed in four sewage treatment plants (of a total capacity of 1,000,000 equivalent population) on the water quality of the Gulf. The calculations show that N is the limiting nutrient and its removal results in an improvement of the quality of the recipient, whereas the additional implementation of P removal has a rather limited impact.

Changes of microbial indices of water quality in the Vistula and Brda rivers as a result of sewage treatment plant operation

2008 ◽  
Vol 37 (2) ◽  
Author(s):  
Maciej Walczak
Keyword(s):  
Water Quality ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Sewage Treatment Plants ◽  
Plant Operation ◽  
Treated Sewage ◽  
Microbiological Parameters ◽  
Microbial Indices

Changes of microbial indices of water quality in the Vistula and Brda rivers as a result of sewage treatment plant operationThis paper reports the results of studies of microbiological changes in the water quality of the Vistula and Brda rivers after the opening of sewage treatment plants in Bydgoszcz. The study involved determining the microbiological parameters of water quality. Based on the results obtained, it was found that the quality of the water in both rivers had improved decidedly after the opening of the plants, although an increased number of individual groups of microorganisms was found at the treated sewage outlet from one of the plants.

Biological Waste Water Rehabilitation of Sugar Factories by Algocoenosis Correction

2017 ◽  
Vol 21 (3) ◽  
pp. 16-20 ◽  
Author(s):  
V.V. Kul’nev ◽  
V.I. Stupin ◽  
A.A. Borzenkov
Keyword(s):  
Waste Water ◽  
Biological Treatment ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Domestic Sewage ◽  
Total Water ◽  
Sewage Treatment Plants ◽  
Total Water Consumption

The article deals with theoretical and practical aspects of biological waste water rehabilitation of sugar factories by algocoenosis correction. This technology allows you to transfer domestic sewage treatment plant of filtration mode fields in the biological treatment ponds mode, significantly reducing the area of sewage treatment plants, thus improving the quality of treated waste water, which will, in turn, use them repeatedly reducing total water consumption.

scholarly journals O PROCESSO DE EUTROFIZAÇÃO ARTIFICIAL NO LAGO PARANOÁ, BRASÍLIA, DF

1994 ◽  
Author(s):  
Gustavo Macedo de Mello Baptista ◽  
Mário Diniz de Araújo Neto
Keyword(s):  
Water Quality ◽  
Sewage Treatment ◽  
Federal District ◽  
High Rate ◽  
Field Methods ◽  
Influx Rate ◽  
Sewage Treatment Plants

This paper represent an academic exercise dealing with some index parameters of water quality usinganalytical field methods. In first instance it aims to demonstrate the praticalness of the methods as well asits level of precision. It was possible to estimate the influence of parameters like NO3, pH, OD (dissolvedoxygen), etc. for the determination of water quality of the Paranoá Lake wich serves as recipient of sewagefrom Brasilia and satellite towns of the Federal District/Brazil, with an estimated influx rate of 140 litersper second. Treatment of this quantity of sewage (during the time of our study) is very simple: just passingby a fence system. Conditions of eutrophication of this water body have become worse due to the inflowof clandestine sewage from houses along the the lake-side, wich contributes much to the increase ofnutrients, especially phosphorus and nitrogen.The obtained results were promising and served to stimulate further studies in the course "Practice ofField Studies", even not serving for a definite characterization of the waters. It is important to emphasizethat neither results nor the analysis of the data are focused in this paper.The high rate of eutrophication at the sampling stations can be observed using NO3 e PO4 as parameters.In that sense the following measures are recommended in order to maintain chemical and physicalcharacteristics of the habitat:1 - dredging of organic mud from the bottom of the lake, since it contains 80% of the phosphates ofthe slop, besides other nutrients;2 - expansion or construction of new sewage treatment plants in order to prevent the inflow ofsewage in natura in the lake and to satisfy the demand of the population;3 - control of clandestine sewage of the houses at Lake South and North by the official environmentalprotection agencies punishing house owners with application of heavy fines;4 - development of environmental education programs for scholars of all levels in order to arouse theconscience for preserving of water resources.

Optimization of Nutrient Removal in Stockholm

1991 ◽  
Vol 24 (7) ◽  
pp. 103-111 ◽  
Author(s):  
G. Brattberg ◽  
L.-G. Reinius ◽  
M. Tendaj
Keyword(s):  
Nutrient Removal ◽  
Sewage Treatment ◽  
Water Source ◽  
Chemical Precipitation ◽  
Phosphorus Load ◽  
Sewage Treatment Plants ◽  
Limiting Nutrient ◽  
Baltic Proper ◽  
Mechanical Stage ◽  
The Baltic

Stockholm was founded at the point where the waters of Lake Mälaren emerge into the Baltic Sea. Lake Mälaren is the water source of the water works of Stockholm. The Lake also receives water from one of the sewage treatment plants. The outlet from the two other sewage treatment plants are in the inner part of the archipelago. During 1968-73 the treatment was improved, after which the phosphorus load to the receiving water significantly decreased. The total P concentration in the surface water has decreased since 1970 and phosphorus has replaced nitrogen as the most limiting nutrient throughout the entire archipelago within 50 km from Stockholm. To further reduce the eutrophication a continued reduction of the phosphorus load is most effective. For the Baltic proper as a whole, where primary nitrogen limitation is present, it is important to reduce the supply of nitrogen to the greatest possible extent. The treatment plants in Stockholm are located in subsurface rock-chambers. The treatment includes mechanical, biological and chemical treatment. In the mechanical stage the sewage is treated in screens, grit chambers and primary sedimentation. The biological stage is a conventional activated sludgeprocess. For the chemical precipitation ferroussulphateis added before the screens. The sludge is stabilized in anaerobic digesters and dewatered in centrifuges before disposal on farmland. To meet more stringent requirements on nitrification and nitrogen removal several projects are going on to optimize the nutrient removal. The aim of these investigations is to improve the plants' performance within the existing plant.

What Advantages Can Be Expected from the Acceptance of Variable Quality Standards for Sewage Treatment Effluents?

1988 ◽  
Vol 20 (4-5) ◽  
pp. 249-251
Author(s):  
Jacques Bernard
Keyword(s):  
Water Quality ◽  
Sewage Treatment ◽  
Quality Standards ◽  
Quality Level ◽  
Environment Protection ◽  
Economical Benefit ◽  
Quality Objective ◽  
Set Up ◽  
Variable Quality

The flow and the water quality of the rivers vary throughout the year. Very frequently the environment protection authorities set up a quality objective for the river water and this mini mum quality level is constant. So, it wou1d seem possible to accept variable quality standards for plant effluents. A first approach of the problem,by a small French task group,based on three actual cases leads to the provisory conclusion that such a regulation is suitable and presents economical benefit only in some very limit ed cases.

scholarly journals Nutrient water quality of the Wye catchment, UK: exploring patterns and fluxes using the Environment Agency data archives

2003 ◽  
Vol 7 (5) ◽  
pp. 722-743 ◽  
Author(s):  
H. P. Jarvie ◽  
C. Neal ◽  
P. J. A. Withers ◽  
A. Robinson ◽  
N. Salter
Keyword(s):  
Water Quality ◽  
Sewage Treatment ◽  
Quality Data ◽  
Agricultural Activity ◽  
Spatial And Temporal Variability ◽  
Water Quality Data ◽  
Climatic Fluctuations ◽  
Mass Load ◽  
Environment Agency

Abstract. Water quality data, collected by the Environment Agency in England and Wales over 10 years (1991 – 2000) were used to examine the spatial distribution of nutrient pollution risk and for assessing broad-scale spatial and temporal variability in nutrient fluxes across the Wye catchment. Nutrient water quality across the upper and middle Wye catchment, and along the main River Wye, is generally very good. However, the main areas of concern lie in the small tributaries in the south and east of the catchment, which have lower dilution capacity and high agricultural and effluent inputs, and where mean Total Reactive Phosphorus (TRP) in some cases exceed 1 mg-P l-1. Indeed, mass load calculations have demonstrated that the lowland south and east portion of the catchment contributes more than 85% of the whole-catchment TRP and more than 78% of nitrate (NO3‾) loads. Ratios of NO3‾:Ca were used to fingerprint different water-types across the catchment, linked to weathering and agricultural activity. The Wye catchment has been subject to two major sets of perturbations during the study period: (i) climatic fluctuations, with a drought during 1995-6, followed by a subsequent drought-break in 1997/8, and extreme high river flows in the autumn/winter of 2000/2001, and (ii) introduction of tertiary P-treatment at major sewage treatment works in the catchment. The implications of these perturbations for the nutrient water quality of the Wye catchment are discussed. Recommendations are made for more targeted monitoring to directly assess diffuse source nutrient contributions. Keywords: nutrients, phosphate, phosphorus, nitrate, nitrogen, river, Wye, PSYCHIC, Defra

Implementation of Community Wetlands for the sanitation of the Cajititlan Lake, Jalisco

2021 ◽  
pp. 14-21
Author(s):  
Juan Luis Caro-Becerra ◽  
Luz Adriana Vizcaíno-Rodríguez ◽  
Ramiro Luján-Godínez ◽  
J. Guadalupe Michel-Parra
Keyword(s):  
Aquatic Vegetation ◽  
Lemna Minor ◽  
Sewage Treatment ◽  
Typha Latifolia ◽  
Basic Function ◽  
Floating Structures ◽  
Sewage Treatment Plants ◽  
Quality Of Water ◽  
Vegetation Species

Wetlands are systems that promote the sustainability and development of a society. The goal of this research was the implementation of a prototype aquatic garden to assess the quality of water in Cajititlán Lake, using sewage treatment plants with the purpose of removing nutrients, phosphates and nitrates among others parameters. This was made possible by floating structures containing aquatic vegetation species like.: Typha latifolia, Lemna minor, Canna indica, Iris pseudacorus, Equisetum arvense, etc. whose basic function is to retain nutrients through phytoremediation processes. The results indicate that the implementation of community wetlands made possible to reduce BOD levels from 220 mg/lt to 12 mg/lt across a surface of 120 m², treating a flow rate of approximately 5.30 gal/min to obtain an effluent in accordance with norm NMX-AA-012-SCFI. It is concluded that community wetlands are suitable ecological alternatives for the treatment of the wastewater discharged directly into the lake.

Evaluation of the impact from the discharge of treated sewage on the south-east Saronicos Gulf through mathematical water quality modelling

1999 ◽  
Vol 39 (8) ◽  
pp. 63-70
Author(s):  
C. Noutsopoulos ◽  
E. Gavalaki ◽  
A. Andreadakis
Keyword(s):  
Biological Treatment ◽  
Critical Factor ◽  
Field Measurements ◽  
Substantial Improvement ◽  
Disposal Site ◽  
The South ◽  
Treated Sewage ◽  
Limiting Nutrient ◽  
The Impact

The paper presents the results of a study of the impact caused by the discharge of treated sewage from the south-west Attiki area to the south-east coast of the Saronicos Gulf. The study involved the application of a eutrophication-dissolved oxygen model which, following validation on the basis of field measurements, was applied to predict the impact of three different biological treatment configurations, with and without nutrients removal, as well as three alternative disposal sites on the quality of the receiving waters. The simulation results show that nitrogen is the limiting nutrient and that its removal during treatment results in a substantial improvement of the quality of the recipient. The disposal site is a critical factor in the case of a biological treatment scheme exhibiting carbon removal, but it is of limited importance in the case of treatment systems with nitrogen removal.

Enteric Bacteria Survival Factors

1992 ◽  
Vol 25 (12) ◽  
pp. 93-103 ◽  
Author(s):  
M. Pommepuy ◽  
J. F. Guillaud ◽  
E. Dupray ◽  
A. Derrien ◽  
F. Le Guyader ◽  
...  
Keyword(s):  
Water Quality ◽  
Light Intensity ◽  
Sewage Treatment ◽  
Enteric Bacteria ◽  
Bactericidal Effect ◽  
Mediterranean Coast ◽  
Shellfish Farming ◽  
Two Parameters ◽  
Very High

In order to improve bacterial water quality of shellfish farming areas, studies were conducted in the English Channel (Morlaix) and on the Mediterranean coast (Toulon). These two areas were chosen in order to compare behaviour of fecal bacteria in two different ecosystems. In the estuary of Morlaix sediments are polluted by way of settlement, but most of the bacteria are mixed with turbid waters and are able to survive a very long time (T90 are in a range of several hours to several days). By measuring the increase in salt tolerance of the strains grown in natural organic matter, it was demonstrated that Salmonella can tolerate coastal water salinities. Moreover, because light penetration is prevented by suspended matter, the solar bactericidal effect is very low. On the contrary, through lack of nutrients and very high sunlight intensity, die-off rates in Mediterranean waters are very high (at the surface T90 are less than 2 hours, and several hours in deep waters). A close relationship was found between the light intensity received by bacteria and the T90. Predicted T90 must be found using these two parameters(including turbidity and deep effect on light intensity). The authors suggest that precautions must be taken to carry out impact studies depending on water quality of the area, especially in turbid areas. The knowledge of these mechanisms is very important to evaluate waste water impact on the quality of shellfish farming areas, and to improve elimination of fccal bacteria in sewage treatment plants.

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