In this research study, we are using CFD to better understand processes in a wastewater settling tank. Secondary sedimentation tanks belong to the most important objects at the wastewater treatment ...line. CFD plays an important part in better understanding the processes from a standpoint of operation and optimization. We conducted four CFD simulations based on a verified model of a secondary settling tank at the wastewater treatment plant in Nitra, SK. The four simulations contain four different adjustments to the inlet zone of the tank. We reached a reduction in sludge zone velocity to 6 from 12 mm/s in a representative measurement profile. We also analyze the influence of temperature-induced viscosity changes based on seasonal temperature change.
Graphical abstract
Wastewater treatment process consists of several steps. Separation of sludge from water is one of the essential. Correct design of the settling tanks is therefore crucial for its operation. In case ...that these objects don’t work properly, they cause problems in the whole ecosystem as they lead to the increased load to the recipients. In this paper proper data collecting method is investigated and data collection is described. Actual point velocity of flow in the secondary settling tank was measured in several points throughout the tank. Measurement was carried out in WWTP Dolný Kubín and WWTP Nižná nad Oravou in Slovakia and these data are used for model calibration and verification. Consequently, simulation of the flow in the tank will be provided. Modelling of the flow in this type of conditions is difficult therefore it is necessary to find right tool to perform precise work. Data that were obtained by measurement have been supplemented by the data provided by the operation of the WWTP.
The aim of this study is to focus on environmental benefits, or eventual loads of sludge life cycle in the wastewater treatment process. Life Cycle Assessment was used to evaluate the ...environmental impacts associated with the treatment of wastewater in a wastewater treatment plant (WWTP) in Vráble, based on the general standard EN ISO 14040. From the measured experimental data, the environmental impacts of the sludge management are quantified using the LCA method. For impact assessment is using the OpenLCA program, together with the available databases and assessment methods. The LCA results of Vráble WWTP taking renewable energy as the energy source proposed that enhancing the effluent quality will decrease the environmental impacts.
V súčasnosti je v rámci kalového hospodárstva potrebné orientovať sa v smere ďalšieho znižovania kontaminácie kalov, a to aj z pohľadu organickej kontaminácie v zmysle právnej úpravy ...pripravovanej EÚ. Technológie kalového hospodárstva je potrebné nielen zdokonaľovať, ale súčasne aj optimalizovať a racionalizovať. Tieto požiadavky sa na poli výskumu a vývoja premietajú do zvýšen.ho záujmu o nové poznatky z oblasti kalového hospodárstva.
The landfill is a dynamic object, in which occurs to mineralization of wastes and their correlative reactions. Stored wastes undergo through many physical, chemical and biological changes. The rate ...of these processes increases with temperature and moisture up to a certain upper limit. The result of these activities is leachate and landfill gas. Predicting quantity of leachate is a critical parameter in the design of landfill construction. Created amount of leachate influences the way how to capture, collect and process the leachate. In resolving that issue, it's important to design optimal water regime of landfill order to ensure the elimination of potential environmental pollution. PUBLICATION ABSTRACT
The lack of detailed knowledge about the interaction of the velocity field and suspended sludge poses an obstacle in designing more effective sedimentation tanks. This study investigates the use of ...CFD analysis of hydraulic processes and the influence of seasonal temperature change on a waste water treatment sedimentation tank. The object analysed in this pilot research is a part of the WWTP in Nitra-Dolné Krškany, SK. The analysis was conducted using the CFD model ANSYS Fluent
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, supported by field measurement data, which was gathered on two separate occasions in July 2015 and February 2016 at the sedimentation tank during operation. Three parameters were collected in 400 measurement points throughout the tank. During the research we analysed the data, looking for correlation with the CFD simulation to verify the results and correlations between the winter and summer period to determine the influence of varying temperatures.
Graphical abstract
Sludge management is an integral part of every sewage treatment plant. The quality and quantity of sludge produced is dependent on the kind of wastewater treatment technologies, quality and quantity ...of inflowing waste water and not least by seasonal conditions during the year. The paper is analyzing sludge management of the existing wastewater treatment plant Nitra -Dolné Krškany. In our research we are analyzed these main parameters: concentrations of heavy metals and nutrients, microbiological parameters and the quantity of sludge. The paper analyses the calendar year 2015 and also evaluates the impact of seasonality during the different months.
The primary mechanical treatment of waste water relies heavily on settling. Combined with the need of secondary settling after activation, makes the settling process the key procedure in treatment of ...waste water. This article aims to compare different types and configurations of inlet zones and a quick analysis of their impact on the overall efficiency of settling in the tank, using CFD simulations.
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