Vol 53, No 9-10 (2018)

Based on the postulates of the hydrodynamics of slow motion and process parameter values close to realistic values, a quantitative analysis of the process of separating a liquid water + oil system in a hydrocyclone was performed.

Thermal fractionation in a column with stages made of horizontally mounted trays is studied. Absorption and fractionation are used as examples to show that mass transfer can be enhanced if the liquid on the trays is rotated. It is established that the efficiency increases if the speed and the concentration of volatile component in the mixture increase because the liquid and vapor phases are mixed better. The overall efficiency is improved by two and more times during thermal fractionation in a column with 10 contact stages.

Two- and three-pass film evaporator designs were developed. High performance of the evaporators is achieved through the use of distribution devices. Diagrams were developed for connecting multipass film evaporators to the columns in rectification systems. A model to describe the distribution of the liquid phase in the rising film section of the evaporator tubes was designed, taking into account the differences in the liquid level near the most loaded and the least loaded tubes of this line. The designed model was investigated. In the model, the evaporation of a six-component mixture of rectification column residue from the production of commercial o-xylene was considered. The effect of the liquid level in the lower distribution chamber around the most loaded and least-loaded heat exchanger tubes on the specific flow rate and variability of fluid flow in the tubes with the rising liquid film, the flow resistance of the tubes, and the fraction of evaporated steam was determined.

An analysis showed that the investigated liquid (gasoline, kerosene, and diesel fuel) and gaseous hydrocarbons may be of interest as feedstocks for high-purity hydrogen production using membrane-catalytic systems with sufficiently high technical parameters.

Methods for the organization of safe manufacturing processes and for the control of technological risk in Russia and abroad are considered. The structure, problems, and types of estimation (levels) of risk and the advantages of the method of Risk Based Inspection (RBI), a method for optimizing programs of inspection and maintenance, are set forth.

Plasma hardening by a standard UDGZ-200 unit makes it possible to provide not only a marked increase in steel 20Kh13 hardness and wear resistance, but also an improvement of corrosion resistance. Under experimental conditions, the corrosion resistance of steel 20Kh13 after hardening increased by a factor of 1.86, but decreased somewhat (by 15%) in the transition area to unhardened metal.

A technique of estimating the parameters of the vulcanization process based on a solution of the direct and inverse problems of the kinetics of the vulcanization process is considered. It is shown that the computation technique yields a high degree of precision of the results obtained as well as making it possible to select an optimal vulcanization regime.

A method for the design of the flow path of a main oil pump by means of which the geometry of the flow path may be optimized to achieve maximum energy efficiency of the pump is given. The method is based on mathematical simulation of the hydrodynamic processes that occur in the flow path of a pump using the ANSYS system of finite-element analysis combined with methods of nonlinear programming.

The addition of analytic point estimators of the stress state of the elements of structures obtained as a result of a calculation based on current regulatory documents with the use of numerical and interval point estimators that expand representations of the laws governing the deformation of a structure is proposed as a means of increasing the reliability of representations of the loading power of load-bearing units. The proposed multi-model approach to the study of the stress state of structurally complex power structures is tested on the housing of an evaporator plant.

Features of the change in microstructure of manganese white cast iron of grade ChG5D2F4 with the use of plasma action are studied. Plasma hardening treatment leads to an increase in wear resistance due to an optimum phase composition and degree of residual austenite metastability.

A comparative analysis is provided for turning caprolon using replaceable polyhedral plates made from different materials, and in fact made of tungsten-cobalt alloy VK8 and ceramic material, i.e., tungsten-free hard alloy KNT60. It is established by experiment that for machining caprolon workpieces it is expedient to use replaceable cutting tools made from ceramic materials KNT60, which makes it possible to expand the range of tools used and improve turning efficiency as a whole.

A complex optimization criterion that takes into account the integral quadratic error and the stability margin of a robust digital control system for the rectification column used for the butylene-divinyl fraction is proposed. The influence of the weight coefficient, taking into account the ratio of the performance and stability indicators, on the dynamic characteristics of the system is investigated. High system performance and system stability indices over a sufficiently broad range of variation of the parameters of the rectification column are achieved through the use of the proposed optimization criterion and a stability estimation algorithm in the synthesis of a robust digital control system.

Magnetic nanoparticles of an iron oxide (Fe₃O₄) encapsulated in hyper-cross-linked polystyrene (PS) were used as a sorbent for recovery of phenols from waste waters. The encapsulated magnetic sorbent Fe₃O₄-PS was prepared by suspension polymerization. Sorption of phenol and 4-nitrophenol onto Fe₃O₄-PS was studied under dynamic and static conditions. The recovery of 4-nitrophenol was 96%; of phenol, 64%.

Mathematical models relating ultrasonically measured velocities and attenuation coefficients of sound to the basic physical and mechanical properties of rubbers were considered. The models were used for the development of methods for express quality assessment of rubber wastes. A compact universal minilaboratory for express analysis of rubber properties based on ultrasonic non-destructive control methods was offered.