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The article describes the methodology of physical and mathematical modeling of the mechanism for ejection of chips of a disk chipper. This technique allows you to calculate and optimize the design and technological parameters of the chip ejection mechanism. To accomplish this task, the flow of chip elements was divided into separate spherical elements, and the working surfaces of the chip ejection mechanism are represented by a set of fragments of planes conjugated to each other. When creating a mathematical model for calculating and optimizing the design and technological parameters of the chip ejection mechanism, the following indicators of the efficiency of the chip ejection mechanism were analyzed: the rate of chip ejection at the exit of the chipping line, the probability of chip ejection from the first revolution of the chipping disk, the mechanical power consumed for the ejection of chips after the stage of crushing the cut residues knives. The mathematical model is implemented in a computer program in the Object Pascal language in the Delphi 7 development environment. The program allows carrying out computer experiments to analyze the movement in the casing and chipping of chips obtained from felling residues and to study the effect of the design and technological parameters of the ejection mechanism on the efficiency of the disk chipper. The computer studies carried out made it possible to determine the best numerical ranges of the chipping disk rotation frequency and the number of blades located on the chipping disk. The likelihood of chip entrainment at the first revolution of the chipping disk and the power consumption for the ejection of chips from the disk chipper were also determined.

It has been presented the study results of the firing process of cellular ceramics from granulated foam glass. The chemical, mineral and granulometric compositions of the raw materials are given. It has been shown the characteristic of ceramic-technological properties of raw materials. The samples were burned from the granulated mixture in the temperature range of 850-1000 ° C. It has been established the change dependence in the physicomechanical properties of cellular ceramic samples on the temperature and firing duration. The results of the study of the macro-and microstructure of cellular ceramics are given. It has been revealed the effect of intensive formation of the pyroplastic phase and the connection between small pores at a temperature of more than 950 ° C. After the enlargement, the cells leave the three-phase ceramic system and it was the increase in the average density of cellular ceramics is 1.4-1.5 times. The influence of a solid glass-ceramic shell along the inner surface of the pores on the decrease in water absorption of cellular ceramics to 6.5-7% is established.

A model of the transition layer between the shell and the core of a ceramic matrix composite from coal waste and clay has been developed. The chemical, granulometric and mineral compositions of the beneficiation of carbonaceous mudstones and clay were studied. The technological and ceramic properties of raw materials for the samples manufacturing were determined. The method of manufacturing multilayer ceramic samples from coal waste, clay and their mixture is given. The number of transition layers in the contact zone between the clay shell and the core from coal wastes is determined. The deformation and swelling phenomena of model samples from coal wastes, clay, and their mixtures were revealed at the firing temperature of more than 1000 °C. The formation of a reducing ambient in the center of the sample with insufficient air flow is shown. The influence of the carbonaceous particles amount and the ferrous form iron oxide in the coal wastes on the processes of expansion of multilayer samples during firing has been established.

The process of forming, by means of a proposed technology, the transitional layer between a dispersed medium and a dispersed phase of a ceramic matrix composite is investigated and a method of fabricating multilayer samples modeling at the macro level the interface between phases in the direction matrix–core of the composite material is presented. A qualitative and semiquantitative analysis is presented of new phases which are products of an interaction, occuring during firing, of a core made from sludgy iron-ore wastes and a matrix made from clayey raw material.

It has been given the design and general view of a unit for determination of settlement of press-powders under bilateral compression of ceramic products. The device of the fixed and movable holder-clamp for measuring settlement of the powder allows the use of compression unit in hydraulic presses of various designs. It has been shown the scheme of preparation of the press-powder from loam for testing the unit in the lab conditions. It was described in details the sequence of experimental determination of settlement of the press-powder under bilateral compression. The compression curves of the lower, upper, and total settlements of the press-powder are presented. The functional dependencies between the settlement and the pressing pressure were determined by the method of approximating polynomial. There are given the equations of the sixth order, which shows complete coincidence of the calculated and experimental compression curves. The compression unit and the method for determining optimal pressing parameters ensure the manufacture of defectless raw material without fractures of delamination and overpressing with considering particularity of material composition and technological properties of clay raw materials.

In the conducted study we developed design of a mold for pressing hollow ceramic. The results of investigations of granulometric, chemical, mineral compositions and technological properties of waste from coal argillites enrichment and clay raw materials are presented. It is described the technology of manufacturing granular press powders based on coal waste. The distribution and structure of the powdered granules are shown. The investigations of ceramic samples of the matrix structure have been carried out and the formation of an inner zone of dark gray in solid samples during firing process has been revealed. Carbon burning is stopped Inside the samples without oxygen access and hematite is reduced to protoxidic form. It was noticed the absence of a dark center in hollow samples. It has been established the formation of a matrix structure in ceramic products. The necessity of oxidizing atmosphere for firing and hollow form of ceramic products from coal waste is substantiated.

Studies on structure, phase composition and properties of ceramic wall materials with a glass-crystalline framework from dispersed silica-rich rocks are described. The results of chemical, mineralogical and granulometric compositions of tripolite and granulated foam-glass crystalline material (GFGCM) are presented. The dependence of physical and mechanical properties of cellular ceramic materials on GFGCM content in the composition in the amount from 5 to 75% is determined. Test samples of cellular ceramic materials with dimensions 250 × 120 × 65 mm, having a compressive strength 16.2-20.8 MPa, water absorption 7.1-7.9 % and an average density 0.99-1.32 g/m3 were produced at the factory. At the macroscale level the cellular structure of the ceramic material consists of closed pores with a vitrified inner surface pore, glass-crystalline outer shell of the pores and solid phase of the framework walls. It was established that after firing in the temperature range 850-900 °C the walls of the framework are represented by quartz, feldspar and hematite, a pronounced halo is indicating a significant amount of glass phase.

There are given technological factors of pressing of products from ceramic powders. The pressing process is represented as a functional dependence with a set of variables. Four stages of ceramic powders pressing have been found. The method on determination of the pressing parameters of ceramic products using the mounting for curves readout has been shown. Sediment of press powders from clay raw material is determined at different humidity and pressing pressure. The dependence of the physical and mechanical properties of ceramic samples on the humidity content of clay powder and the pressure of raw pressing is established. Compacting pressure values have been found by compression curve when plastic deformation ends and elastic deformations of powder grains start, which corresponds to a translation from the second to the third stage of the pressing process. Areas of rapid deceleration of sagging are in line with the point of the tangent to this curve in the translation from the third to the fourth compression stage have been found. The optimal values of semidry pressing of a ceramic brick have been defined.

The research results of the material, chemical and mineral compositions of waste coal from the processing plant Abashevskaya and carbonaceous argillites from the Korkino coal mine are provided. The technology of waste coal recycling is offered that can be used in the production of coal fuel for bricks burning and preparation of the raw material for ceramics manufacture. On the basis of the pilot plant tests it is shown that the pneumatic waste classification allows coal residues to be extracted from argillites and a stable ceramic raw material to be obtained for the brick manufacture. Such complex processing of waste coal does not only provide a significant expansion of the raw material base for the production of building materials and generation of additional energy, but will also help to solve environmental problems and improve the environmental situation in industrial regions. Due to the introduction of the patented method of production and rational compositions of the granulated molding materials there is an increase in operational properties of ceramic wall materials produced from the waste coal after secondary processing. The study of thin sections using a polarizing microscope and SEM was conducted to examine the structures of the obtained ceramic cork. It was established that high physical and mechanical properties of the brick were achieved by forming the matrix structure of a ceramic crock, intensive generation of the glass phase at the interphase boundary of the composite material and the temperature reduction of processes of a solid-phase sintering during burning.

The given paper investigates the influence of manganese-containing wastes on bulk coloring and physical and mechanical properties of wall ceramic materials with matrix structure. Conventional research methods to study physical and mechanical properties of ceramic specimens were used in the present study. The structure and phase state of decorative ceramic materials were investigated by means of physical-chemical analysis. Authors suggested the model to form coloring layer in ceramic matrix composites based on argillaceous raw materials and coloring pigment. Macrostructure was studied on ceramic samples manufactured according to the developed method from clay loam of moderate plasticity and wastes of manganese mining. The paper provides results of pilot testing on production of colored ceramic brick. It was found that incorporation of coloring component does not decrease strength properties of ceramic matrix materials. Authors defined the palette and color code for decorative ceramic specimens manufactured with different content of coloring component of manganese mining wastes according to RGB color codes chart.

The analysis of waste coal from mining enterprises of Kemerovo region as raw materials for production of building ceramics is given. The results of studies of material, chemical and mineralogical compositions of waste coal from Abashevskaya processing plant (Novokuznetsk) are presented. It was established that the chemical composition of waste coal refers to aluminosilicate raw materials with a high content of alumina and coloring oxides, the residual carbon content in the wastes is 12-25 %. According to the granulometric composition the waste coal is basically a sandy-dusty fraction with a small amount of clay particles (1-3 %). Additional grinding of coal waste and the introduction of a clay additive in an amount of up to 30 % are recommended. The results of the study of the mineral composition of waste coal are presented. Clay minerals are represented in the descending order by hydromuscovite, montmorillonite and kaolinite, minerals-impurities consist of quartz, feldspar fine-dispersed carbonates. The results of the investigation of ceramic-technological properties of waste coal, which belong to the group of moderately plastic low-melting raw materials, are given. As a result of a comprehensive study it was been established that with chemical, granulometric and mineralogical compositions waste coal with the reduced residual carbon can be used in the production of ceramic bricks.

The results of the study on phase transformations and structure formation during firing of bricks made from wastes of coaly argillite processing. The effect of firing temperature on the processes of mineral formation and changes in the quantitative content of amorphous phase and brick porosity was defined. It was found that at 950-1050 °C the sintering takes place providing a solid brick structure.

Rational preparation of the mixture containing technogenic raw material - waste coal for the production of wall ceramics is developed. It was established that the technology of high-quality ceramic bricks requires: grinding of raw materials to class 0.3 + 0 mm, its aggregation in the intensive mixers into granules 1-3 mm, compression molding of adobe to plastic deformation of granules, drying and firing.

The results of fly ash research, generated in the process of waste coal combustion in the thermal vortex power units and used as an aggregate in aerated concrete, are provided. It is established that fly ash can be used in the production of cement or concrete with low loss on ignition (LOI). The permitted value of LOI in fly ash, affecting the structure formation and operational properties of aerated concrete, are defined. During non-autoclaved hardening of aerated concrete with fly ash aggregate and LOI not higher than 2%, the formation of acicular crystals of ettringite, reinforcing interporous partitions, takes place.