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The increasing attention focused on environmental problems in the world has caused further stiffening of the requirements for the quality of motor fuels. Future requirements for environmentally clean automotive gasolines are provided in the following standards: sulfur -maximum of 0.05 wt. %, including mercaptan sulfur -maximum of 0.001 wt. %; aromatic hydrocarbons -maximum of 25 wt. %; unsaturated hydrocarbons -maximum of 5 wt. %; benzene -maximum of 1 wt. %.Naphthas from destructive processes -catalytic and thermal cracking, coking, and visbreaking -are a significant proportion of commercial fuel in refineries that exhaustively refine crude oil. These petroleum products are the basic source of sulfur and unsaturated hydrocarbons in commercial gasoline, which makes it necessary to solve the problem of refining them.Research is being conducted in the Department of Oil Refining Technology at I. M. Gubkin RSU of Oil and Gas to enhance hydrogenation processes and rationally utilize distillates of secondary origin. Variants and schemes have been proposed for using visbreaking naphtha (for Moscow Oil Refinery Co. and Ryazan' Oil Transhipment Co.), catalytic naphtha (for Ryazan' Oil Transhipment Co.), thermocracking and coking naphtha (for LUKOIL-Volgogradneftepererabotka Co.) in feedstock for hydrogenation processes and technology for comprehensive utilization of distillates from thermodecomposition processes. These developments resulted in an increase in commercial gasoline resources as a result of improving the quality of substandard secondary distillates and manufacture of products that satisfy current environmental and performance requirements on available equipment with minimal outlays for revamping the units.Secondary distillates containing unsaturated, heteroatomic, and aromatic compounds can be refined with hydrogenation processes. Direct hydrotreating of thermal distillates for improving their properties involves a number of features: important release of heat (335-420 kJ/kg) in hydrogenation; partial polymerization and condensation of olefins in heating, which causes deposits to accumulate in the heat-exchange equipment and in the upper layer of catalyst.One method of refining secondary distillates is to include them in feedstock for hydrogenation processes where hydrogenation of double bonds takes place together with hydrogenolysis of organosulfur compounds.However, in this case, up to 10 octane number points are lost in attaining the required sulfur level. It is particularly useless for catalytic naphtha with a high octane number to undergo hydrotreating. 147Another method of improving the properties of secondary distillates is refining by stages. They first undergo hydrotreating mixed with straight-run distillates and then the hydrogenation products obtained go to reforming. This is the most rational solution of the problem, especially for naphtha distillates. To obtain a high degree of hydrogenation of sulfur-containing and unsaturated compounds in one reactor, it is desirable to use no more than 10-15% s...

It is possible to assume physical properties or stress-strain characteristics of material as a basis of diagnostics of a machine tool system state on the basis of which to forecast a level of engineering process updating for product blank machining and to optimize tool parameters and other equipment components ensuring efficient machining processes economically and technically. The purpose of the work: according to the measurement results of the mass of replaceable hard-alloy cutting plates of a metal-cutting tool to draw a conclusion of their operational capability under those or other operational conditions at a standard engineering enterprise. There are considered standard designs of cutting and chip breaking plates. The mass measurements of more than 250 plates are carried out. The procedure for the plate selection according to quality is developed. The results obtained are tabulated and illustrated. A share ratio of suitable and scrap plates is shown. There are formulated recommendations regarding suitable plates use depending on their quality grade.