ABSTRACT 

In the fuel-energy complex of Ukraine as well as in chemical-recovery and metallurgical industries coal will for a long time stay one of the main constituent.

The most important way of coal cost price decreasing is mechanization of coal output and production automation. But the mechanization of output is inevitably attended by ash value, humidity, and fine portion increasing in coal output.

Solution of tasks concerning increasing of finished concentrates is connected with the processing of fine which content in the ordinary coal constantly increases.

Transportability and cost of such products depend on the humidity, which high value which decreases the efficiency of these materials’ exploitation.

Updating of the technologies connected with fine particles and pulp is the main purpose of manufacture.

The greatest difficulties are connected with dehydration of fine and thin particles. Porosity and penetrability of these mediums are usually low. Dehydration of such sludge is made in several stages. The combination of mechanical and thermal dehydration is more frequently used.

In comparison of these dehydration principles from the position of ecological and cost evaluation the first method is preferred as a rule. Increasing of fine sludge dehydration effectiveness allows saving the energy that is used at thermal finishing for achieving marketable humidity.

Aim of the work is research of physical phenomena’s effect in increasing of sludge impenetrability.

The aim of the present work, using modeling of sludge’s and its porous medium’s behavior in different dehydrating conditions, is searching the approaches for research and modeling of sludge structure, their physical and mechanical properties; exploration of possible variants of sludge conditions; carrying out of tests of density and plastic sludge’s properties; compression tests of sludge and tests of filtration sludge’s properties; carrying out of shearing tests.

The obtained results of the present work allow proving the shear application time point for intensifying of dehydration process, and choosing the efficient modes of dehydration in shearing deformation spheres.

As it has been determined by many researchers, structure of sludge, especially such characteristics as penetrability, substantially influences the process of dehydration. Making modeling of sludge and their porous medium behavior in different dehydrating conditions it’s necessary to find the approaches for researching and modeling of sludge’s structure and their physical and mechanical properties. In the process of mineral raw stock enrichment humidity is determined in the most cases and granulometric composition is determined much rarely. At the same time sludge generation includes a great quantity of different physical processes.

The main ones are the following: hydrodynamic, mechanical and filtration processes. At the second (mechanical and filtration stage) stage of sludge generation the main role have the mechanical processes of sludge solid phase’s deformation simultaneously with filtration processes, which are attended by moisture expression from porous environment. Mechanical processes include compression (sludge compression by ordinary mechanical force), consolidation (shrink of solid phase under the constant load), and shear of solid phase’s structure under shear stresses.

These important components of mechanical phase of sludge generation are characterized by the range of parameters. For example, the compression characteristics of sludge shall be described by compression indexes and modules of solid phase deformation. At drifting of solid phase under shear stresses it’s necessary to know the limit of sludge shear strength, module of shear, rate of seal failure that accompany the shear and other important characteristics that haven’t applied in the process of raw stock enrichment.

There characteristics allow estimation of compressibility, sludge’s strength, liquid’s filtration speed and energy output of dehydration mechanical processes. Such mechanical parameters are widely applied in soil mechanics. There exist well-tested methods of stated characteristics tests and testing laboratory equipment was developed. In connection with this it will be reasonable to specify the range of concepts which are used in the process of exploration in rock and soil mechanics.

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