Том 52, № 1-2 (2016)

A method of calculating the temperature distribution in reaction devices using electromagnetic radiation in the UHF range as the energy source to realize the reaction is presented. It is shown that when carrying out catalytic reactions, the electromagnetic radiation absorbed by the substance of the catalyst creates volumetric heat sources in the catalyst the energy of which is transmitted to the reaction mixture in the gas phase through processes of heat exchange. The technological operating conditions of electrodynamic reactors in which a uniform temperature fi eld needed to perform chemical transformations is created are determined. A comparison of the computed and experimental data for the catalytic reactions of dehydration of butenes is carried out and it is shown that the proposed mathematical model supplies a sufficiently precise description of the actually occurring processes.

Here is an analysis of the quality requirements for basic nitrogenous fertilizers specified in the national, local, and international regulatory documents. An industrial plant has been developed for producing very high quality ammonium nitrate and calcium ammonium nitrate (CAN) granules with a capacity of up to 80 thousand tons/year by pelletization. The necessary quality characteristics of the granules can be achieved by using the proposed reconstruction of the active units without stopping their operation.

The efficiency of application of polymer composites with ecologically safe fillers for the preparation of rings used in mass transfer column units is studied. The dependence of mass and heat transfer coefficients on the filler concentration during contact of air and water in the column unit is shown.

A mathematical model of automation and control system of a sucker-rod well pump with a beam drive is developed. It can be used to analyze the automation system operation stability and, consequently, the consistency of operation of the automation system with the technological unit and modes of its operation.

Equations for use in determining the basic parameters of a multichamber face gland seal, such as the number of chambers and the forces of pre-loaded fastening elements, are presented. A uniform distribution of the load on the packing along the length of the seal in the case of a minimal load (based on the airtightness of the connection) is thereby achieved, thus assuring a decrease in the losses in power caused by friction in the seal.

Questions are considered for optimizing and intensifying the traditional technology for preparing carbon fluoroplastic composite for piston compressor friction assemblies. A technology is developed for composite preparation and manufacturing methods in each stage, making it possible to create highly efficient and economically substantiated composites for piston compressor assemblies operating under dry friction conditions.

Effective methods for dispersing carbon nanotubes in organic solvents and liquid polymeric media were analyzed. The relationship of these methods for improving the operational performance of nanomodified polymer composites was studied. It was shown that the conditions necessary to create such materials are a small size and a distribution of carbon nanofiller particles as uniform as possible in the liquid polymeric matrix. The tendency of the carbon nanofiller to aggregate prevented the preparation of stable dispersions in water and organic solvents. Therefore, effective methods for facilitating aggregate disintegration, including use of low-frequency ultrasound, are being actively pursued.

Methods of numerical simulation of flow hydrodynamics in equipment with irregular packing layer are discussed. An algorithm of direct simulation method is described, focusing special attention on the grid model creation stage and the choice of turbulence model. Comparison of numerical and physical simulation results shows their satisfactory agreement.

The mechanism of dispersion of metals in the presence of high molecular compounds is shown on the example of grinding high speed R6M5 steel swarf. It was shown that metal pulverization is more energetically favorable in the presence of a mechanically degradable polymer than in the presence of low-molecular weight surfactants.

A face gland seal in which the packing is not divided into individual chambers is presented. The packing is pressed by the end face of an axially moveable ring caused by a force created by the pressure of the compacted medium. This force produces a minimal unit axial load that is uniformly distributed along the length of the packing and is specified by the air-tightness condition. The tightening force of the threading elements and losses of power caused by friction of the packing are reduced. Required computational expressions are presented.

The possibility of using microwave radiometer sounding for monitoring dangerous fire situations in forests is examined in this article. The need to use complex multi-frequency sounding is justified. The possibility and expediency of using a multi-channel scanning aviation complex to solve the stated problem are evaluated.

Extraction of nickel, iron, and zinc hydroxides and metallic nickel from galvanic sludges of Saratov Region industries is reported. It was established that the products could be used to produce pigments and fillers for paints and to fabricate rechargeable cathodes of chemical current sources (Ni–Cd and Ni–Fe batteries).

The main packings used in biotrickling filters for air-gas purification are discussed and classified and new packings are offered in the present work. The packings are compared overall according to their geometrical characteristics. Changes of the filter-packing principal geometric characteristics (specific surface area, porosity, equivalent diameter) because of the growth of a biofilm over time are found experimentally. A new parameter, the modernized equivalent diameter considering the change of packing channel cross section due to biofilm growth, is introduced. Equations based on experimental data for calculating the total drag coefficients of the new packings are derived.

Factors are considered affecting correct evaluation of tank service life: the effect of the form of biaxial stressed state on tank material cyclic crack resistance properties, and the dependence of stress-strained state at the tip of a defect specifying stress intensity factor on operating conditions, defect size, and structure geometric features. A universal algorithm is proposed on the basis of numerical and experimental research for calculating the number of cycles to failure for a tank wall with a crack-like surface defect.

Production aspects are provided for manufacturing sintered tungsten-cobalt alloy VK8 based on tungsten carbide prepared by mechanochemical synthesis. It is shown that experimental alloy VK8 physicomechanical, and operating properties significantly exceed those of commercial grade hard alloy, which opens up possibilities for its use in preparing cutting, drilling, and also stamping tools operating under dynamic conditions.