Vol 52, No 5-6 (2016)

To increase the efficiency of mass-21transfer apparatuses, a stream-bubble contact device with intensive countercurrent contact between the gas (vapor) and liquid in each element is proposed. This way of effecting phase contact helps increase mass-transfer coefficients and, consequently, increase efficiency of masstransfer processes significantly. In the proposed contact device, hydraulic resistance is low. The profile and parameters of liquid drops atomizing may differ markedly, depending on the design and process parameters of the contact device and of the apparatus as a whole.

Correlations of resultant heat transfer efficiency criteria with length of flat flames are obtained for various gaseous and liquid hydrocarbon fuels by mathematical modeling of complex heat transfer in narrowchamber tube furnaces using zonal method. Thanks to this, such temperature fields can be created in the furnace by varying the length of flat flames as would ensure the required uniformity of heat supply at nearmaximum value of integral heat received by a tubular screen.

Examples of import substitution in the design of new or upgrading existing industrial gas cleaning devices in the petrochemical complex are considered. Combined gas separators produced by the Inzhekhim company and the results of their operation in industry are shown as such examples. The efficiency of gas purification is not less than 99% for micron-sized particles.

The process by which a solid substance is dissolved from the floor of a device with nonstationary motion of a stirrer is investigated. An analysis of the influence of the coefficient of irregularity of the rotation of the stirrer on the rate of the dissolution process and the quality of the mixing is presented.

The article describes the calculations and design of a steam jet vacuum system for the column of a hydrocracking unit. Based on calculation results (considering specific operating conditions of the production), several variants of pressure distribution through the pump stages were calculated, and the optimal schematic of the vacuum system was defined, yielding a 20% reduction in energy consumption and a 15% reduction in capital costs.

Promising types of threaded connections selected by the authors as a result of an analysis of inventions of recent years and which they expect will promote an increase in the reliability and competitiveness of machinery and mechanisms in the oil and gas industry are considered.

The effect that intracyclic variation of the rotational velocity of an anchor agitator exerts on the depth of the funnel that arises on the free surface of liquid in the apparatus is investigated. Theoretical and experimental results from estimation of the efficiency of the mixing process as a consequence of an increase in the degree of irregularity of rotation and rate of variation of the angular velocity of the agitator within a cycle are presented.

A mathematical model of the process of rotary rolling out of thin-walled pipe billets is developed. It is used to derive a relationship for the torque as the key power and force parameter of the process, which expresses explicitly the influence of the geometric parameters of the rolled-out pipe, the mechanical properties of the material and the mechanisms of its strengthening, and the structural parameters of the operating tool on the stability of the rotary rolling process. It is shown that use of straight-seamed pipe billets with roller welded joint, in combination with potential application of automatic argon-arc welding of circular joints, can significantly extend the life of pipes made from corrosion-resistant materials.

A mathematical model of a piston compressor, which can be used, given the structural parameters of the compressor and of the intake and delivery valves, to find the time behavior of the amplitude of pressure under the compressor piston as well as of vibration speed and vibration acceleration transmitted as mechanical actions on the equipment and recorded by vibration diagnosis transducers, is proposed. The vibration signal spectra at various compressor model parameters that characterize development of a specific defect are studied.

The article is devoted to the study of the process of obtaining biogas by anaerobic fermentation of biomass of various origins. The main advantage of the suggested theory is the possibility of utilizing organic waste with a complex morphology and of changeable composition. The developed method of bioconversion of organic waste presented a high ecological and economical efficiency. The article presents some data concerning the anaerobic fermentation substrate characteristics, and the description and working principle of the experimental unit.

Separation of oil-in-water emulsions based on I-20A industrial oil and Kosintol-242 surfactant by membranes made of polyethersulfone (PES) with a molecular-mass cut-off of 50 kDa and polyacrylonitrile (PAN) with a molecular-mass cut-off of 60 kDa that were treated in a DC (unipolar) corona-discharge field is investigated. It is shown that the performance increases for filter elements of modified PES and remains the same if electretized PAN membranes are used. Additionally, the separation efficiency of the emulsion increases for both types of membranes after processing in a DC corona-discharge field.

The problem of evaluating the state of gas cylinders in the course of technical examination and the evaluation of the risks that arise in the course of their subsequent service is considered. It is shown that functions of the basic characteristics of the state of cylinders as functions of their service life may be constructed. It is suggested that the relative values of the variations in the measured characteristics and the known probabilistic functions of these indicators should be used for the prediction and evaluation of risks.