Authors:Jaroslav Hrudka, Štefan Stanko, and Michal Holubec
In the process of design and operation of sewerage system are used empirical formulas, which are in many cases, become obsolete and unusable when somebody can use nowadays modern technologies and materials. Therefore there is the possibility of using the mathematical models enormous importance for the enhanced environmental protection with the lowest operating and investment costs. In this modern method of analyzing of sewers has been designated as the first object, the object sedimentation tank. The purpose of the primary and secondary settling tank is to ensure the reduction of concentration the floating solids.
For the solution of research work has been chosen, after consultations with representatives of the Western Slovakia Water Company as interesting object of sedimentation tank located on the waste water treatment plant Nitra - Dolné Krškany.
Measurements on the object settlement tank situated at waste water treatment plant Nitra confirmed the expected speed parameters of the sewage in the tank. The velocity of wastewater is in the most cases very low, and even insignificant. However, finding that the sludge cloud has a non-standard form of a double wave gives the opportunity to optimize the operation of facilities sedimentation tank. The measured parameters are used as calibration parameters to input to the mathematical simulations, which are created by software ANSYS fluent.
Authors:Dušan Rusnák, Štefan Stanko, and Ivona Škultetyová
Appraisals results of divided and combined rain sewers highly depend on the appropriate choice of model rain. The goal of this research is to verify the impact of different rain models on results of rainfall totals, calculated flow in the network and in their overall effect on the assessment. This research focuses on three main rain models - block rain (reduced), a synthetic rain and actual historical rain with data collected from meteorological stations allocated in the area of Vráble. Historical rain event for the area has been chosen as the one with highest overall intensity with duration of at least 1 hour. Modeling process has been conducted in interface of MIKE URBAN software.
Authors:Dušan Rusnák, Štefan Stanko, and Mária Trošanová
Assessments of sewer systems are key tools in verification of sewer hydraulic capacity. Rain sewers and combined sewers are most susceptible regarding system overload and so while assessing them; proper choice of design rainfall is inevitable. The calculation of design rainfall is time-consuming and inefficient and that was the reason that leads to development of design rainfall analysis tool in order to minimize the length of the calculation process of design rainfall. The tool incorporates calculation of design rainfall depending on the specified area of interest within Slovakia and chosen periodicity, allows block rain, reduced block rain and synthetic rain to be calculated with the possibility of their mutual comparison, and also serves to generate background data for further use in form of portable document format and excel files.
Authors:Réka Csicsaiová, Štefan Stanko, and Mária Dubcová
The implementation of Directive 91/271/ECC concerning Urban Wastewater Treatment, leads to increase in the number of waste water treatment plants in Slovakia.The contribution is aimed at assessing the environmental impacts of the wastewater treatment process within the wastewater treatment plant using life cycle assessment. Life cycle assessment is an optional environmental management tool that focuses on the entire life cycle of a product and uses assessment methods to determinate adverse environmental impacts. The assessment of wastewater treatment plant is focused to the analysis of the individual factors identified by the physical-chemical analysis of wastewater. The correct application of the ISO 14040 standard assigns the accuracy of the analysis results and determines the individual elements of the system. Based on this ISO standard the system boundaries, the functional unit and the subsystems are defined.
Authors:Ivana Marko, Štefan Stanko, and Réka Csicsaiová
This paper is about comparing the effectiveness of the sorbent materials of granulated activated carbon in removing of bromates from drinking water. The limit value (10 µgl−1) of bromates in the drinking water was stated by World Health Organization. In order to insure the reduced concentration of bromates in the drinking water, an experiment was performed using the batch test. In this experiment different types of sorbent materials with different properties were testing. Based on batch test were measured the parameters like the immediate adsorption capacity, the adsorption efficiency, and the concentration of bromates after the adsorption were measured at the evaluated time.
Authors:Réka Csicsaiová, Štefan Stanko, Ivana Marko, and Jaroslav Hrudka
The article is aimed at finding out the behavior of the combined sewer network in the event of the occurrence of extreme precipitation events, which are associated with changes in the rainfall - runoff process in the urbanized area. Given the current situation of increased surface runoff in the urbanized area, it is necessary to extend the use of objects to reduce rainfall to the sewerage network. Part of the case-study was the design of percolation facilities in town Vráble, which are among the most used and most effective reduction measures. After designing the infiltration equipment and reducing the amount of rainwater discharged into the single sewerage network, the assessment of the sewerage network is satisfactory throughout the whole territory.
Authors:Marek Šutúš, Jaroslav Hrudka, Gergély Rózsa, Ivona Škultétyová, and Štefan Stanko
This research deals with creating a hydrodynamic combined sewerage overflow chamber model an ANSYS Workbench 19.2, Fluid Flow (Fluent). The 3D graphics model was created in the SpaceClaim modeling software, which serves as the basis for hydrodynamic modeling. The model was created according to a real combined sewerage overflow chamber in Banská Bystrica. The cores of the work are simulations that should correspond to the estimated flow in the combined sewerage overflow chamber. The aim of this paper is to compare the impact of inflow speed and flow rakes.
Authors:Réka Csicsaiová, Ivana Marko, Jaroslav Hrudka, Ivona Škultétyová, and Štefan Stanko
The aim of the study is to assess the hydraulic capacity of the sewer network and sewer collector recovery in the urban catchment area of Trnava.
The analysis focuses on the evaluation of situations with different precipitation frequencies. Elaboration consists of modeling the current state of the assessed sewer collector B and subsequent loading of this collector by several block rainfalls. Based on the results of the analysis, the recovery of the sewer network proposed.
Authors:Ivana Marko, Réka Csicsaiová, Jaroslav Hrudka, Ivona Škultétyová, Štefan Stanko, and Paula Brandeburová
The aims of the research are to focus on the analysis of qualitative parameters of surface runoff from the urbanized area (parking, roadways); subsequently, to compare the measured concentration with the recommendations of Danish and Slovak standards. Rainwater sampling carried out at several sites in Serbia and Slovakia. In the analysis were monitoring, the qualitative parameters as pH value, water conductivity, chemical oxygen demand, and heavy metals. The results show the presence of copper, zinc, lead, aluminum, cadmium, chromium and nickel. The concentration of these parameters was several times higher than the allowed limit values. Based on these results, it is necessary to design measures to ensure surface runoff before infiltration.