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An analysis has been made of the factors affecting filtration and sediment formation processes, the sediment structure, and the resistance of the filtering partition (baffle plate). A method has been developed to find the volume resistance of the sediment based on Kozeny-Karman equation that takes account of the influence of the structural parameters (porosity and mean diameter of sediment particles). This method has been shown to be usable for calculating filtration and dehydration processes and for obtaining data required for selecting auxiliary equipment (vacuum pumps, receivers, traps, etc.) for industrial vacuum-filtration plants.For building industrial filtration plants, determination of the parameters of the sediment filtration and dehydration (dewatering) processes is of great importance. Proper selection of the auxiliary equipment (vacuum pumps, traps, receivers, etc.) is of particular importance for large-capacity plants because on it depends to a large extent the efficiency of the equipment (output, moisture content of the sediment, efficiency of operation of the filtration department, etc.) [1].As is well known, the parameters that decisively affect filtration processes with sediment formation and dehydration are specific resistance of the sediment layer and resistance of the filtering partition (baffle plate). The data obtained in the methods used to determine these parameters vary widely. In view of this, solution of this problem is urgent for theoretical research and industrial filtration.The purpose of this work was to refine further the methods of investigation of the sediment structure and to obtain more precise relationships for determining the parameters of the sediment filtration and dehydration processes.Analysis of factors affecting filtration process. Filtration is a highly complex process in chemical technology. Its distinctive feature is influence on the filtration process of two basically different groups of factors -macro-and microfactors [2].The macrofactors group includes such variables as surface area of the filtering partition, pressure differential, sediment layer thickness, viscosity of the liquid phase, etc. These variables can be determined precisely making use of appropriate instruments. To the microfactors group belong the size and shape of the sediment pores and of the filtering partition, the thickness of the double electric layer on the surface of the solid particles, etc. For quantitative evaluation of the variables of the microfactors group, use is made of indirect methods, which do not provide precise data. However, use of these methods is fully justified for solving particular problems [2].The microfactors, on which the structure of the sediment depends, decisively affect the filtration process and greatly complicate its modeling [2].

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Basic equations (laws) of various filtration processes (with the formation of sediment, intermediate, and standard laws, filtration with decreasing number of open pores in the filter), as well as equationsfor determination of dewatering parameters are examined. As an example, optimal operating regimes of a vaccum disk filter were defined via computer for determination of the law and parameters of the filtration process.Filtration is one of the most widespread processes employed for the treatment of products that differ with respect to their properties. The problem of determining filtration parameters is urgent in this connection [1][2][3][4].For this purpose, methods based on computer facilities are being employed all the more widely. Nicolaou [5], for example, presents results of investigations of the separation parameters of suspensions, especially for processes in a continuous-action disk vacuum filter, which were obtained by computer methods.Moreover, modern procedures have been proposed for determination of parameters of a filtration process with the formation of a sediment, which make it possible to accelerate the design of industrial filtering equipment and determine their optimal operating conditions on the basis of these procedures.In addition, separation processes in filters may, as previously conducted investigations have demonstrated [6,7], also proceed in accordance with other laws. In this connection, the procedure proposed in this paper calls for preliminary determination of the law, according to which the filtration process proceeds, and more accurate determination of process parameters for subsequent analysis of industrial filters. Determination of Laws and Corresponding Filtration ParametersBasic equations for different filtration processes are presented in Table 1, where τ is the time of filtration in sec; V′ is the volume of filtrate obtained per unit area of filtering surface in m 3 /m 2 ; R 1 is the overall filtration resistance, as applies to An iron-ore concentrate with a solid-phase particle size of 0.044 m (GOST 15054-80), volume concentration of 66%, and specific surface of 1910 cm 2 /g was selected as an example for determination of the law and parameters of the filtration process. A fabric with the trademark Voskresenskaya 0597/106 (filtration-surface area of 0.0013 m 2 ) was used as the filtering partition. The filtration was carried out in a laboratory unit under vacuum, and the volume of filtrate measured at five points over time ( Table 2).Results of the analysis indicated that for the case in question the filtration proceeds according to the law with sediment formation (Figs. 1 and 2).Parameters of the filtration process, which correspond to this law, were then determined -the average specific resistance of the sediment, and the resistance of the filtering material, as applies to a unit of viscosity (Figs. 3 and 4).An engineering analysis of the filtration (Figs. 5 and 6) and dewatering (Figs. 7 and 8) processes, which were conducted on a filter with the trademark DOO 100-2.5-1U ...