PERFORMANCE EVALUATION VERTICAL SETTLERS SEWAGE SYSTEMS BY NUMERICAL MODEL

Problem statement. Rational use and increase of efficiency of sewage treatment one of the major tasks in the field of water supply and the sewerage. Not the last part in ensuring operability of a complex of treatment facilities is played by settlers of various types which are used both at a stage of mechanical cleaning, and for division of the cleared water from silt mix after biological cleaning. Today the introduction tendency in practice of operation of settlers which form significantly differs from the classical is observed. Such settlers have a number of the internal design features allowing to improve water purification process. In Ukraine for calculation of settlers of systems of water disposal traditionally use empirical [2; 3], balance [9; 13] or one-dimensional kinematic models [8; 10; 12; 14; 18]. These models are simple and economic in practical application, but don’t allow the designer to consider a hydrodynamic operating mode of a settler, to vary in the wide range of the sizes and that is especially important, design features of settlers of treatment facilities. In Ukraine multidimensional CFD (Computational fluid dynamics) models which would allow to calculate a field of concentration of impurity in a settler taking into account formation of a zone of a deposit, aren’t developed. Purpose. The paper presents a 2-D numerical model of heat transfer in a vertical settler, allowing to take into account when modeling the geometric shape of the settler, its design features, a zone of formation of sediment. Shape and size of the possible formation zone of sediment can be pre-estimated from experimental data or observations on objects, and setting it in the developed mathematical model of “play” different scenarios specific to each case. Conclusion. In work the new numerical model for calculation of process of a mass transfer in sewer vertical settlers is presented. Appli-cation of mathematical modeling allows to consider the geometrical sizes of settlers, design features, and also kinetics of upholding of sewage. On the basis of the constructed numerical model the specialized code is developed which can be used as the tool of the solution of a complex of the tasks arising at design and reconstruction of vertical settlers which will allow designers to estimate quickly efficiency of water purification at a stage of justification of design pa-rameters of a clearing construction is developed.