ENGINEERING MODELS OF OIL REFINING: INCREASING THE EFFICIENCY OF MULTI-STAGE GASOLINE PRODUCTION

Abstract

The relevance of this study is caused by the need for import substitution of software in the field of design, modeling and optimization of the gas and oil processing. Almost all software for modeling used at oil and gas entities are the developments of the USA, Canada, Great Britain and other countries. In the current conditions of sanctions risks on using imported software for modeling technological processes, the development and rapid adaptation of engineering mathematical models of all basic oil refining processes are an extremely urgent task. These models will further become the basis of Russian import-substituting software products. Over the course of 30 years, the National Research Tomsk Polytechnic University has been researching the processes of the motor fuels production. On the basis of these studies the reliable mathematical models have been developed for technologies such as catalytic reforming of gasoline, isomerization of the hydrocarbons pentane-hexane fraction, catalytic cracking of vacuum distillate and mixed petroleum feedstock, hydroprocessing of petroleum fractions, compounding of high-octane gasolines, and others. Distinctive features of the developed mathematical models are related to following: firstly, they are built on the basis of real industrial data on the operation units at various refineries and, secondly, they take into account the main fundamental physical and chemical laws of reaction mechanisms, the catalyst deactivation as well as the macrokinetic factors of motor fuel production processes. The solution of multicriteria problem of optimizing the technology of preparation of motor fuels (gasoline and diesel fuels) is possible using the method of mathematical modeling on a physical and chemical basis. This approach takes into account the thermodynamics and kinetics of hydrocarbon conversions on the catalyst surface, as well as the non-stationarity of the processes due to coking, aging and poisoning by harmful impurities of the catalyst, changes in the chemical composition of the feedstock. The aim of this study is to develop the technical solutions aimed at improving the efficiency of multi-stage gasoline production using the engineering models of oil refining processes. The method of research is based on using the mathematical modelling method for multi-stage processes of petroleum feedstock refining. The group and individual composition of various petroleum fractions determined by chromatographic methods, were used as an initial data. Results. The effect of the component composition of the processed feedstock of catalytic reforming on the qualitative and quantitative properties of the components of commercial gasoline was estimated and predicted. The use of the catalytic cracking model showed that when processing the feedstock with a lower content of aromatic hydrocarbons and resins the coke content on the catalyst is lower by 0,15 % wt. This leads to increasing the catalyst activity and the desired product yields by 6,7 % and 4,9 wt. % in comparison with the feedstock with higher content of resins and aromatics.The maximum gasoline yield for two types of the feedstocks (55,4 and 56,5 % wt.) which is achieved at 536,0 and 534,0 °C was determined according to their hydrocarbon compositions. The predictive calculations with an assessment of how the composition of the catalytic cracking gasoline influences the formulation and commercial quality of the commercial gasoline using the lighter catalytic cracking feedstock, were performed. The possibility of increasing the amount of the catalytic cracking gasoline into the commercial gasoline formula is shown. The cost of motor fuel production in this case is reduced from 0,1 to 1,0 %.

Keywords

• engineering models
• catalytic reforming
• catalytic cracking
• gasoline
• optimization
• efficiency improvement