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The relevance of the research is caused by the need to maintain the required quality and increase light oil products output at low-power oil refineries under conditions of variable composition and consumption of raw materials. The problems of improving management quality become more serious in the conditions of small oil refineries. They have not their own production base and they have to purchase a lot of oil from various oil production organizations. Therefore, raw materials with different composition often come for processing. One of the difficulties in developing oil distillation control system is the necessity to use laboratory data of petroleum products quality indicators. This force to use the simplified control algorithms that can operate on the basis of the data received with the big delay. The aim of the research is to achieve maximum output of light petroleum products in the atmospheric distillation cube in conditions of variable flow rate and composition of raw materials improving the control system. Research objects: atmospheric distillation unit for low-capacity oil (less than 500 thousand tons per year). Methods of the research are based on automatic control theory, heat and mass transfer theory, mathematical modeling and simulation. Research. The authors have stated the task of managing the low productivity atmospheric rectification unit and determined some features of the control object. Input and output parameters as well as the optimization criterion were choose. The paper introduces the method of managing using the mathematical model. The structure of management system using Matlab is given. The method provides a growth in extraction of light oil products by decreasing a variability of oil fractions boiling temperatures.

In this work, a novel ultrasonic-assisted thermal cracking method for improving the yield of light oil from the thermal cracking of Huizhou atmospheric residue (HAR) is proposed and demonstrated. To achieve this, a self-developed autoclave ultrasonic reactor (20 kHz; 200 W) was designed. Gas chromatography (GC), and elemental analyser (EA) were employed to analyse the composition of gaseous and liquid products after the cracking of residual oil. Compared to the traditional thermal cracking process under similar conditions (430 °C; 8 MPa; 2 h), the ultrasonic-based process produced lower gas products ( ca . 0.6%), higher gasoline and diesel fractions ( ca . 10%), vacuum residue, and lower yield of coke yield ( ca . 4%). In addition, coke produced by the ultrasonic-assisted thermal cracking method exhibited spherical morphology with narrow size distribution and smooth surface with small amounts of adsorbents attached to it. The derivative characteristic peak (101 crystal face) at 2 θ of 43.56° belonged to α -graphite. The abnormal high local temperature and pressure conditions produced by ultrasonication were the key factors for the thermal cracking of residual oil. The experimental results indicated that the ultrasonic-assisted thermal cracking can dramatically lead to higher yield of light oil, higher degree of cleavage, and more favourable reactions under the same conditions (as those of traditional thermal cracking). Therefore, compared to the traditional delayed coking process, the proposed ultrasonic-assisted technology can significantly decrease the power consumption. This study has vital significance in predicting and enhancing the performance of thermal cracking on a large scale. [ABSTRACT FROM AUTHOR]

Upgrading of oil sand bitumen by catalytic cracking of its heavy oil fraction via ceria-based catalysts was investigated in a fixed-bed flow-type reactor, in the presence of superheated steam and addition of water. The reaction was carried out over CeZr, FeCoCeZr1 and FeCoCeZr2 catalysts at 470 °C, W cat /F Feed of 0.4 h and F H2O /F feed  = 2. The oxygen species in the crystal lattice of the catalysts and the surface Lewis acid sites are responsible for the oxidative decomposition and catalytic cracking of the heavy oil, respectively. Higher light oil yield of approximately 60 mol%-C (gas oil and vacuum gas oil) and lowest coke yield (20.45 mol%-C) was obtained over CeZr catalyst. FeCoCeZr1 and FeCoCeZr2 gave lower residue and higher gas yield, with higher H 2 and lower CO 2 composition when compared to CeZr. The spent catalysts showed structural stability which is supported by the X-ray diffraction analysis, and thermal stability which agrees to the minimal weight loss from thermogravimetric analysis. The catalysts also exhibited good potential for reusability based on the analysis of the spent samples. [ABSTRACT FROM AUTHOR]

The saturated and aromatic hydrocarbon maturity characteristics of crude oils from the eastern Chepaizi High in the Junggar Basin of northwest China were analyzed in detail. The results show that sterane maturity parameters for light oils from the Neogene Shawan Formation differ from other maturity parameters. Sterane αααC 29 20S/(20S + 20R) and C 29 ββ/(ββ + αα) ratios indicate low maturity, while aromatic hydrocarbons indicate high maturity. We infer that light oils from the Shawan Formation have higher maturity than Cretaceous and Jurassic crude oils and were generated at equivalent vitrinite reflectance of ∼0.9–1.2%. It can be concluded that the Shawan light oils originated mainly from deeply buried, highly mature Jurassic source rocks, southeast of Sikeshu Sag, southwest of Shawan Sag, and west of Huomatu Anticline Belt. During upward migration, crude oils generated from Jurassic source rock dissolved less mature Cretaceous bitumen resulting in a mixture with apparently conflicting parameters. Phase fractionation during migration also could have contributed to the anomalously low sterane maturity parameters. [ABSTRACT FROM AUTHOR]

In order to establish suitable conditions for the production of feedstocks or liquid fuels from a renewable source, a liquefaction process of lignin obtained from sugar cane bagasse was investigated. Monoethanolamine was used as liquefaction solvent and hydrogen as pressurization gas. Liquefaction process was optimized using a modified simplex method consisting of three variables: temperature, time, and solute:solvent ratio. The goal of the proposed method was to maximize the yield in light oils that was achieved with a total of only 27 experiments and with a yield 5 times higher than the initial one, obtained before the optimization procedure. [ABSTRACT FROM AUTHOR]

In this work, a study of the effects of four variables (time, temperature, pressure, and solvent/solute ratio) upon the liquefaction process of the cellulose obtained from sugar cane bagasse aiming to obtain light oils is described. The goal was to determine the importance of these variables upon the process, as well as the interactions between these variables, by using a factorial design, 24, with two levels and four variables. It was verified that only two variables involved in the process had influenced the yield in light oils: time and temperature. [ABSTRACT FROM AUTHOR]