Vacuum Residue Research Articles

Comparative study of single- and two-stage slurry-phase catalytic hydrocracking of vacuum residue for selective conversion of heavy oil

The selective conversion of asphaltenes to light products while inhibiting coke formation is the most challenging in the heavy oil upgrading process. Herein, single- and two-stage slurry-phase catalytic hydrocracking of vacuum residue (VR) at various reaction temperatures (350–430 °C) were performed to elucidate the advantages of low temperature conditions and the synergistic effect of two-stage operation on asphaltene conversion. Despite the slow reaction rate at a low reaction temperature, almost no coke was produced, and the selective conversion of asphaltene to deasphalted oil (DAO) was improved with a large amount of H2 consumption. To overcome the low reaction rates at low temperatures, catalytic hydrocracking was performed at two-stage temperatures (380 and 430 °C). Two-stage catalytic hydrocracking showed a synergistic effect of suppressing coke formation while maintaining an enhanced reaction rate compared to single-stage catalytic hydrocracking. This is because the first stage of hydrocracking at 380 °C facilitates the saturation of heavy polyaromatic molecules, which can easily crack in the second stage at 430 °C. However, because two-stage hydrocracking requires a slightly longer reaction time than single-stage hydrocracking to achieve the same conversion, the efficiency of asphaltene conversion must be considered by setting appropriate operating conditions.

Novel insight into structure and content of olefins in thermally cracked heavy oil and its saturates, aromatics, resins and asphaltenes fractions determined by 1H NMR spectroscopy

The factors leading to olefinic hydrogen signal shielding in the 1H NMR spectra of thermally cracked vacuum residue (VR) and its heavy fractions were revealed using a series of model compound systems, and the effect of olefinic hydrogen signal shielding on the determination of olefinic hydrogen content was elucidated. There were two main factors leading to the olefinic hydrogen signal shielding in the 1H NMR spectra of olefins in heavy fractions, i.e. intramolecular and intermolecular. For the olefin itself in heavy fractions, the chemical shift of the olefinic hydrogen closest to the aromatic ring was in the aromatic region rather than the olefinic region due to the π-π conjugation effect between the double bond and the intramolecular aromatic ring. Notably, the response intensity of the olefinic hydrogen signal could be weakened or even disappear due to the suppressive effect of the intermolecular aromatic structures in other polycyclic aromatic hydrocarbons (PAHs), while alkanes and monocyclic aromatics had little effect on the olefinic hydrogen signal response. Although the olefinic hydrogen signal was detected merely at about 5.30 ppm in the 1H NMR spectra of heavy fractions, these olefinic structures may be predominantly of the R─CH═CH2 type rather than the R─CH═CH─R′ type. More importantly, the measured olefinic hydrogen content of thermally cracked VR and its heavy fractions may be considerably lower than the actual content, with the measured content being only about 30–40 % of the actual content. This is mainly due to the weakening and disappearance of the olefinic hydrogen signal, coupled with the fact that the integral area of the possible olefinic hydrogen signal in the aromatic region was overlooked when calculating the total integral area of the olefinic hydrogen signal in the 1H NMR spectrum.

The effect of recycle stream on slurry-phase hydrocracking of vacuum residue: An experimental and modeling approach

The effect of the recycle stream on slurry-phase hydrocracking (HCK) of vacuum residue was examined using a continuous bench-scale unit with the aim of attaining process optimization. This was achieved through a model-based approach that links experimental investigations, kinetic modeling, and model-based optimization. The experiments were conducted at various reaction temperatures, liquid hourly space velocity of fresh feed (LHSVFF) and recycle ratios at a pressure of 160 bar, with the fresh feed containing 1000 wt. ppm of molybdenum. The HCK kinetic model was modified to incorporate the recycling effects and accurately predict the experimental data. The adapted model confirmed that the unconverted residue in recycle operating mode (ROM) became more refractory. By implementing the modified kinetic model in a dynamic Simulink model, the prediction accuracy of RES conversions and product yields can be improved by up to 25.1 wt.% in the case of the lowest conversion. A sensitivity analysis using the dynamic model showed that the temperature exerted a greater impact on the RES conversion and recycle ratio in ROM. An operational stability index was also proposed to prevent operation failure in ROM. Finally, an optimal operating condition from the parametric study was found to meet several process goals simultaneously.

Molecular composition of direct coal liquefaction products obtained from the Shenhua industrial plant

The China Shenhua company has built and operated the only large industrial direct coal liquefaction (DCL) plant in the world for 15 years, with an oil product capacity of one million tons per year. However, there is insufficient information on the chemical composition of its products. In this study, the liquefaction product, including the distillate oil and the vacuum residue, as well as the circulating solvent were characterized by gas chromatography – mass spectrometry (GC–MS) and high-resolution mass spectrometry. The liquefaction oil has lower H/C ratio and higher oxygen and nitrogen contents compared to hydrogenation products derived from petroleum. The major component of the liquefaction oil is middle-temperature distillate, which is approximately 70 wt% concentrated in the range of 200–350 °C. Pyrene and perhydropyrene are the most abundant compounds in the liquefaction oil. Hydrocarbons with 1–4 aromatic rings were detected in the liquefaction oil, with skeletons of benzene, biphenyl, naphthalene, fluorene, phenanthrene, pyrene, etc.. Various partially hydrogenated and perhydrogenated aromatic compounds were identified in the oils and they even constitute the major component of the circulating solvent. 2,3-Dihydro-1H-phenalene was also found in high-relative abundance in the oils and has potential to be used as a marker for coal liquefaction produced through hydrogenation processes. Partially hydrogenated polycyclic aromatics exhibit higher dehydrogenation activity compared to tetralin. The organic component in the vacuum residue account for around 60 wt%, with toluene insoluble matter accounting for more than one third. The toluene soluble fraction has an H/C ratio of 0.82 and is mainly composed of aromatic with 4–8 rings. The molecular size and condensation degree of the residue are much higher than those of other fossil fuel-derived aromatic-rich substances. Further studies are necessary to evaluate whether aromatic hydrocarbons with such a high condensation degree are suitable for producing high-performance carbon materials.

High molecular compounds of deep-water Guneshli oil

The article is devoted to the results of the study of the component composition of the vacuum residue of oil from the deep-water Guneshli field, which is produced in the Caspian sector from a depth of 3000–4000 m. The oil is light, low-sulfur, paraffinic (3.7 % solid paraffins), contains a small amount of heteroatoms, without asphaltenes. The vacuum residue (>450 oC) was separated into naphthene-paraffin, aromatic and resin components with the method of column liquid eluent-adsorption chromatography. The structural group composition of individual groups was studied using IR and PMR spectroscopy. As a result, it was found that even concentrates of aromatic hydrocarbons and resins isolated from the residue (>450 oC) are enriched with naphthenic structures, the most valuable compounds that are part of oils and fuels, providing them with high performance properties.

IMPROVEMENT OF FUEL OIL VACUUM RECTIFICATION PROCESS

Primary oil distillation units form the basis of all oil refineries; the quality and yield of the resulting fuel components, as well as raw materials for secondary and other oil refining processes, depend on their operation. Many Atmospheric Vacuum Tubing (AVT) plants are characterized by low recovery of heavy vacuum gas oil. Insufficient selection of heavy vacuum gas oil production leads to a high yield of vacuum residue - tar, which reduces the volume of oil refining in general.The article analyzes ways to improve the process of vacuum distillation of fuel oil at CDU/AVT primary oil distillation units, and searches for ways to increase the efficiency of already built CDU/AVT plants by increasing the selection of heavy vacuum gas oil. Options for technical re-equipment are presented to improve the technical and economic efficiency of atmospheric-vacuum tubing plants with the maximum use of the best achievements in this area and the maximum possible selection of heavy vacuum gas oil at existing primary oil distillation units. The schemes of intensification during vacuum distillation by the method of fractionation of hydrocarbon raw materials by exposing it to electromagnetic oscillations, by the method of gas oil cryolysis. Besides, the schemes of fuel oil distillation according to a two-column scheme and the rectification of half-tar in an additional vacuum column are considered. The main features in the technological design of the process, as well as the features of installation operation, are noted. The proposed schemes make it possible to obtain high-quality feedstock for catalytic cracking and hydrocracking with a high recovery of vacuum gas oil.

An updated functional-group-based approach to modeling the vacuum residue oil gasification kinetics

Gasification of heavy petroleum residues can convert low-value feedstock to hydrogen-rich syngas, which can further be used for power generation and/or chemical production. The present work proposed an updated functional-group-based approach (FGMech) to modeling the gasification of a vacuum residue oil (VRO), which is helpful for better understanding the detailed kinetics of the gasification and improving gasifier performance. Elemental, average molecular weight (AMW) and nuclear magnetic resonance (NMR) analyses were conducted experimentally to characterize VRO, including elemental composition, average molecular formula and the functional group distribution, which were further used for model construction. A lumped mechanism for VRO devolatilization was constructed based on the updated FGMech approach: stoichiometric parameters of stable gases, tars and char were obtained from experiments, while those of radicals were based on the multiple linear regression (MLR) correlations; thermodynamic and kinetic parameters were derived from Benson group additivity method and rate rules, respectively. A merged detailed model was adopted for describing the conversion of gases and tars, and a global model was used for char. To test the reliability of the present model approach, Orimulsion gasification experiments from literature were simulated using an integrated perfectly stirred reactor (PSR) and plug flow reactor (PFR) model. It shows that the present model can reasonably predict measured results under various equivalence ratios, and has better performance on the prediction of CH4 compared with most literature models. Based on model analyses, syngas comes from the conversion of C2H4, H2S, CH4 and char in different gasification stages. Benzene, toluene, naphthalene and 1-methylnaphthalene are initial tar species considered in the devolatilization of the VRO. They can undergo hydrogen abstraction acetylene addition (HACA) and C3H3/C5H5 addition reaction pathways to produce large PAHs.

The Effect of Carbon Nanofibers on the Hydrocracking of Vacuum Residue in the Presence of Formic Acid

This study was devoted to the processing of vacuum residue to produce lighter oil fractions, such as gasoline and diesel fuel. The hydrocracking and catalytic hydrocracking of vacuum residue in the presence of formic acid (FA) were performed in the temperature range of 250–550 °C. Carbon nanofibers (CNFs) were used as catalytic additives. In contrast to conventional hydrocracking, an important stage in the catalytic hydrocracking of vacuum residue is the decomposition of formic acid. Experimental studies on the effect of CNFs on the decomposition of FA demonstrated that CNFs pre-treated in a NaOH solution (CNF (NaOH)s) had the highest activity and selectivity for the production of H2 and CO2. The maximum yield of liquid products in the catalytic hydrocracking process, equal to 34 wt.%, was observed at 300 °C in the presence of CNF (NaOH)s. The characterization of the fractional compositions of the liquid products showed that the ratios of the fractions changed with an increase in the reaction temperature. The maximum concentrations of the light fractions (gasoline and diesel) in the liquid products of the catalytic hydrocracking of vacuum residue were observed at 300–350 °C in the presence of CNF (NaOH)s.

Performance evaluation of reclaimed asphalt pavement rejuvenated with Waste Engine Oil and Vacuum Residue in the presence of water

Performance evaluation of reclaimed asphalt pavement rejuvenated with Waste Engine Oil and Vacuum Residue in the presence of water

Enhancement of hydrotreating activity of oil-soluble CoMo6 heteropolyacid for 4,6-dimethyldibenzothiophene and vacuum residue by controlling sulfurization degree

An oil-soluble CoMo6 heteropolyacid was synthesized by modifying the heteropolyacid with a surfactant dioctadecyl dimethyl ammonium chloride, and then was used to prepare highly active sulfided catalyst. The effect of sulfurization degree on the hydrotreating activity of the catalyst was investigated, and the results show that the incompletely sulfurized catalyst exhibited high reactivity for 4,6-dimethylbenzothiophene (4,6-DMDBT) and vacuum residue (VR). The unusual finding was attributed to more CoMoS species and surface oxysulfides, and the latter were probably generated in the partial replacement of O atoms with S atoms during the sulfurization. The acidic oxysulfides (SO42- groups) not only improved the activation of 4,6-DMDBT but also facilitated the cleavage of C-C bonds of the intermediate product 3,3′-dimethylcyclohexylbenzene according to the reaction data and DFT calculation. Besides, the catalysts with incomplete sulfide state exhibited outstanding catalytic performance on the upgrading of VR. The proposed incomplete sulfurization strategy provided a new way to prepare bifunctional hydrogenation catalysts with both desulfurization and cracking activities.

Synergic effects between vacuum residue and polymers for preparing high-performance bitumens

This research presents a laboratory study on a polymer-modified bitumens (PMBs) made with a vacuum residue (VR) as a bitumen extender. Two different PMBs were prepared, one with a plastomeric Elvaloy and the other one with an elastomeric styrene-butadiene-styrene SBS. The mechanical properties of the samples were determined by means Multi Stress Creep Recovery tests (MSCR) and temperature sweep test. The results show that polymers can improve the mechanical properties of bitumen, and the vacuum residue can be used as softening bitumen extender. However, their simultaneous presence highlights non-additive effects giving optimal mechanical properties with a lowered temperature dependence of the viscoelastic properties and a high extension of the usage temperature range. The peculiar effect of the combined action of polymers and vacuum residue was also confirmed by chemical-physical analyses. In fact, Atomic Force Microscopy (AFM) and Nuclear Magnetic Resonance (NMR) relaxometry have shown that vacuum residue and polymers are able to effectively interact with the inner structures of the bitumen to give enhanced performances, with an increased stability upon temperature changes.

Mo–Ni, Mo–Fe and Mo–Ni–W nanoparticles for down-hole upgrading

Patented in situ (in reservoir) upgrading technology (ISUT) converts a portion of the reservoir into a “catalytic reactor” by irreversibly attaching a low percentage of nanoparticles to the reservoir's sand/rock. The nanoparticles are prepared as a dispersion in hot vacuum residue and the hot dispersion is injected into the reservoir with low quantities of hydrogen.MoNi, MoFe and MoNiW nanoparticles suspended in bitumen were prepared, in similar way as in ISUT, and the suspensions treated in a batch reactor. Two different sulfiding agents (ammonium sulfide and thiocarbamide) were added during the preparation of the nanoparticles-bitumen suspension. Particle diameters obtained for the suspensions were determined by NTA. The particles were recovered after reaction and its surface composition determined by XPS. Reaction products were analyzed by high temperature simulated distillation, density, viscosity, sulfur and nitrogen content and stability (P-value). MoNi, MoFe and MoNiW with average sizes of 84, 101 and 93 nm, respectively, were produced. XPS characterization of the Mo–Ni–W particles before reaction showed that Mo and Ni are only partly sulfided, while W was present as WO3. The proportion of the metals in the sulfided state increases after reaction from 39 to 94, 35 to 77 and a 0 to 50 (atomic %) for Mo, Ni and W, respectively. In addition, VR conversions were similar by comparing the thermal and catalytic tests, indicating that VR cracking is mainly thermal. However, viscosity, MCR and S contents were lower, and API gravity was higher when a catalyst was used. Also, catalytic products proved more stable than products obtained from thermal reaction. The reaction carried out using dispersions where thiocarbamide was the sulfiding agent provided products with slightly betterer properties in spite of showing larger particle diameters.

High temperature oxidation of residual oil pyrolysis intermediates for modeling gasification and combustion processes

Developing chemical kinetic models for residual oil pyrolysis, gasification, and combustion is very challenging due to the large number of components and molecular complexity. This study provides experimental data for model development and validation for two residual oils, heavy fuel oil (HFO) and vacuum residual oil (VRO). This study aims to identify and quantify the HFO and VRO pyrolysis intermediates and validate an oxidation chemical kinetic model of the pyrolysis intermediates to provide data for future residual oil model development using hybrid chemistry (HyChem) and functional groups for mechanism development (FGMech) approaches. The pyrolysis experiments were conducted in a bench-scale tubular reactor at atmospheric pressure and a temperature of 1273 K. Detailed compositions of the yields from the pyrolysis of HFO and VRO were analyzed using gas chromatography-flame ionization detection (GC-FID) for the gas yields and gas chromatography-mass spectrometry/flame ionization detection (GC–MS/FID) for the liquids. Elemental analysis was conducted for the solid residuals. The experiment results show similar pyrolysis products from HFO and VRO. A surrogate of major components of the gas products and representatives of benzene and naphthalene derivatives (major compounds identified in liquid products) of the liquid products was formulated and its chemistry was studied by measuring ignition delay times (IDTs) in a shock tube. IDT measurements were conducted for stoichiometric and rich (ϕ = 1 and 3) mixtures, pressures of 20 and 40 bar, and diluents of nitrogen and carbon dioxide. Brute force IDT sensitivity analyses were used to study the effect of pressure, equivalence ratio and diluents on the reactivity of the mixture.

New optical microscopy method for determining the influence of feedstock composition on the morphology of microcarbon residue test petroleum cokes

Predicting the petroleum coke or petcoke morphology tendencies of Delayed Coking feeds is paramount to optimizing refinery operation and profitability. Herein, we report a new analytical methodology employing cross-polarized light optical microscopy (CPL-OM) of Microcarbon Residue Test (MCRT) cokes, followed by image segmentation and statistical analysis to determine several structural parameters, i.e., average area, average Feret maximum, and percentage of isochromatic domains with Feret maximum <8 μm (Feret is defined as the maximum distance between the two parallel planes of a given coke particle). Several advantages over previous CPL-OM methods include using more extensive data sets and machine-learning software to accurately segment images to yield better statistics, eliminating isochromatic domains on edge to reduce error, and stitching multiple images to account for larger domains. The new CPL-OM-image segmentation-statistical analysis procedure was effectively used to determine the influence and predict the morphology of MCRT cokes based on Delayed Coking feed properties (C7-asphaltenes percentage/MCRT percentage ratio and the asphaltene solubility parameter) and in blends of vacuum resids. The structural parameters Feret Max. Percentage <8 μm and average area showed excellent agreement within the errors of the technique. This technique represents a convenient analytical tool to qualitatively rank Delayed Coking feedstocks in terms of coke morphology tendencies.

Do the True Boiling-Point Distillation Yields of Crude Oil Blends Obey the Additive Blending Rule?

Twelve crude oil blends prepared from seven individual crude oils and an imported atmospheric residue were characterized through a true boiling point (TBP) distillation analysis and their density. When comparing the measured TBP fraction yields with those estimated through the application of the additive blending rule, it was found that, for four crude oil blends, the additive blending rule was valid, while for the remaining eight crude oil blends, deviations of the measured TBP yields from the estimated ones were bigger than the TBP analysis’s repeatability limits. By the use of intercriteria analysis evaluation of the data for the deviation of the TBP yields from the additive blending rule and the molar excess volume of the crude oil blends, statistically meaningful relations between the delta TBP yields of light and heavy naphtha, as well as vacuum residue with the molar excess volume, were found. The higher the magnitude of the crude oil blend’s molar excess volume, the bigger the deviations of the TBP yields of naphtha and vacuum residue are. The bigger the deviation of the crude oil blend’s behavior from that of the regular solution, as quantified by the molar excess volume, the bigger the deviations of the TBP yields of naphtha and vacuum residue are.

On the products from the pyrolysis of heavy fuel and vacuum residue oil

Incorporating unconventional fuel sources into the global energy mix is necessary to meet increasing energy demand. One attractive option is the gasification of residual fuels, such as heavy fuels, which produce clean combustible gases. Pyrolysis is the first step in the gasification process, so its understanding can help in the development of the gasification process. The information on the pyrolysis products can serve the development of chemical kinetics mechanisms for gasification of heavy fuels for their efficient utilization. In this study, pyrolysis of heavy fuel oil (HFO) and vacuum residue oil (VRO) is reported. The pyrolysis experiments were conducted in a wide temperature range of 400–1000 °C in a customized tubular furnace-based reactor and products were collected. Both liquid and gaseous products were characterized using a gas chromatography (GC)-mass spectrometry (MS)-flame ionization detector (FID) and Fourier transform–ion cyclotron resonance–mass spectrometer (FT-ICR MS) to understand the presence of different types of compounds. The identified compounds in the liquids were classified as benzene derivatives, naphthalene derivatives, polycyclic aromatic hydrocarbons, saturated and unsaturated hydrocarbons and sulfur-containing compounds. The presence of lighter hydrocarbon fractions in HFO acts as a hydrogen donor and resulted in the formation of more saturated hydrocarbons compared to VRO under pyrolysis conditions. Compounds present in the heavy fraction (with high molecular weight) which could not be analyzed and identified in liquid samples using GC-MS/FID were analyzed using FT-ICR MS. Elemental analyses of solid residues obtained from pyrolysis were also performed. Twenty lighter hydrocarbons ranging from C1-C5 were identified and quantified in the pyrolysis vapors of both fuels.

Microwave-assisted solvent deasphalting of heavy fuel oil and process parameters optimization

As petroleum recovery has progressed historically, the portion of heavier crudes and bottom of the barrel residues from the refining process has increased. These crudes are challenging to process, leaving vacuum residues with large fractions of ash and refractory sulfur due to high asphaltene content. Asphaltenes are known to form coke in catalytic upgraders and deactivate refining catalysts. Asphaltenes, which are present in significant amounts in heavy crudes, are the cause of reduction of combustion efficiency, clogging of refinery pipes, and particulate matter emissions. Asphaltenes can be removed from heavy crudes by solvent deasphalting. But the requirement of a high solvent to oil ratio limits its commercial viability. To lower the requirement of solvent, this study investigates deasphalting of heavy fuel oil (HFO) with n-heptane, n-hexane, and n-pentane by microwave-assisted, ultrasound-assisted, and supercritical solvent deasphalting methods. Among the different methods investigated, the microwave-assisted method was found to be more efficient and removed 88 and 80 wt% of asphaltenes from HFO with heptane and hexane, respectively. Microwave irradiation selectively heats asphaltenes in microwave transparent non-polar solvents and increases the degree of collision of asphaltenes for aggregation and thus precipitation. Besides, resins are readily solubilized by the solvent under microwave heating and thus they are unable to act as peptizing agents of asphaltenes. The optimization of process parameters such as solvent to HFO ratio, microwave power, and holding time was investigated for microwave-assisted deasphalting using Central Composite Design (CCD) and artificial neural network (ANN). The optimum removal of asphaltene was observed when the solvent to HFO ratio, microwave power, and holding time were kept at 3, 150 W, and 20 min, respectively. Deasphalting also significantly improved the quality of HFO by dropping the viscosity along with the sulfur and nitrogen contents of HFO. The outcomes of this study are significant for the petrochemical industry as potentially improved crude oil processing with lower solvent to HFO ratios can be achieved in a more effective, economical manner using microwave assistance.

Modelling of a vacuum residue hydrocracking in an industrial slurry phase reactor

AbstractThe upgradation of the bottom of the barrel has gained much interest across the refineries due to severe environmental rules, limitations of conventional oil reserves, and its flexibility to produce light end products which benefit end users. Slurry phase hydrocracking is one of the growing technologies to fulfil the increasing demand for light cut. Modelling of an industrial slurry phase reactor (SPR) for vacuum residue hydrocracking using different kinetic models is proposed. The axial dispersion model (ADM) is used for modelling an industrial SPR. The mathematical model of the reactors is incorporated for the three different lump kinetic models. This study deals with the continuous stirred tank reactor (CSTR) and SPR modelling, followed by industrial SPR modelling. The small lab‐scale reactor models are validated with the experimental data reported in the literature. The study's objective was to investigate the one‐dimensional and two‐dimensional concentration dynamics of each lump along the axial and radial positions of industrial SPR. The vacuum residue conversion into the light fractions was obtained by more than 73% in industrial SPR. Also, the yield of vacuum gas oil and resins were evaluated as 49% and 63%, respectively. The sensitivity analysis was performed to explain the effect of process variables. The optimum range was found as a length of 15 m, liquid hourly space velocity (LHSV) of 0.2 h−1, 1% catalyst concentration, and 420°C reaction temperature to enhance the throughput of the reactor.

Effect of Crude Oil Quality on Properties of Hydrocracked Vacuum Residue and Its Blends with Cutter Stocks to Produce Fuel Oil

The production of heavy fuel oil from hydrocracked vacuum residue requires dilution of the residue with cutter stocks to reduce viscosity. The hydrocracked residue obtained from different vacuum residue blends originating from diverse crude oils may have divergent properties and interact with the variant cutter stocks in a dissimilar way leading to changeable values of density, sediment content, and viscosity of the obtained fuel oil. H-Oil hydrocracked vacuum residues (VTBs) obtained from different crude blends (Urals, Siberian Light (LSCO), and Basrah Heavy) were diluted with the high aromatic fluid catalytic cracking (FCC) light cycle, heavy cycle, and slurry oil, and the low aromatic fluid catalytic cracking feed hydrotreater diesel cutter stocks and their densities, sediment content, and viscosity of the mixtures were investigated. Intercriteria analysis evaluation of the data generated in this study was performed. It was found that the densities of the blends H-Oil VTB/cutter stocks deviate from the regular solution behavior because of the presence of attractive and repulsive forces between the molecules of the H-Oil VTB and the cutter stocks. Urals and Basrah Heavy crude oils were found to enhance the attractive forces, while the LSCO increases the repulsive forces between the molecules of H-Oil VTBs and those of the FCC gas oils. The viscosity of the H-Oil VTB obtained during hydrocracking of straight run vacuum residue blend was established to linearly depend on the viscosity of the H-Oil vacuum residue feed blend. The applied equations to predict viscosity of blends containing straight run and hydrocracked vacuum residues and cutter stocks proved their good prediction ability with an average relative absolute deviation (%AAD) of 8.8%. While the viscosity was found possible to predict, the sediment content of the blends H-Oil VTBs/cutter stocks was recalcitrant to forecast.

STUDY OF THE INTENSIFICATION OF THE DEAPHALTIZATION AND CATALYTIC CRACKING PROCESSES IN A MAGNETIC FIELD

The deasphalting process of the vacuum residue has been studied in the magnetic field in order to odtain the suitable DAO for mixing with the vacuum gas oil for the subsequent catalytic cracking process conducted in a constant magnetic field. The probable mechanism of action of a magnetic field on the de-asphalting process has been studied. The study examined the catalytic cracking of a mixture of vacuum gas oil and tar deasphalted oil products in the presence of a magnetic field, and found that the findings could serve as a foundation for producing high-quality gasolines with high octane ratings. The quality of the deasphalted oil obtained was found to be impacted by a range of factors, including the process temperature, settling time, and solvent-to-raw material ratio. Taking these variables into account, the study evaluated the effect of magnetic treatment on the raw materials during the deasphalting process, and identified the optimal conditions for achieving the desired results. The researchers also explored the impact of magnetic treatment on the settling time and discovered that it accelerated the settling process. In addition, the explanation of the mechanism of action of a costant magnetic field on the process of catalytic cracking in terms of singlet-triplet state of ions and radicals has been given. Keywords: deasphaltization, catalytic cracking, deasphaltization temperature, magnetic treatment of raw materials, asphalt-resin substances.