Heavy Oil Processing Research Articles

Comparative pyrolysis kinetics of heavy oil and its SARA fractions using distributed activation energy model

The pyrolysis behaviors of Qingdao vacuum residue (QD-VR) and its SARA (saturates, aromatics, reins, and asphaltenes) fractions were evaluated by thermo-gravimetric with mass spectrometer (TG-MS). The pyrolysis kinetics were determined by Friedman, one-parallel and four-parallel distributed activation energy model (DAEM), respectively. The results indicated that the pyrolysis behavior of QD-VR was similar to that of aromatics. For saturates, the release of H2, CH4, CO, and CO2 occurred in 80–400 °C, while the temperature range for QD-VR and other fractions is 200–800 °C. The average activation energy (Ea) via Friedman method was 179.72 kJ/mol and increased with the conversion ratio. One-parallel Gaussian DAEM was more suitable to describe the pyrolysis process of the single SARA fractions, while four-parallel Gaussian DAEM was more suitable to describe the pyrolysis process of heavy oil. Furthermore, comparing the weighted Ea from one-parallel (227.64 kJ/mol) and four-parallel Gaussian DAEM (204.63 kJ/mol), the results suggested that during pyrolysis process of heavy oil, there was an interaction between the SARA fractions, which could reduce the Ea of heavy oil pyrolysis. Specifically, during heavy oil pyrolysis, resins and asphaltenes could increase the Ea of saturates and aromatics, while saturates and aromatics could decrease the Ea of resins and asphaltenes.

Use of Nickel Oxide Catalysts (Bunsenites) for In-Situ Hydrothermal Upgrading Process of Heavy Oil.

In this study, Nickel oxide-based catalysts (NixOx) were synthesized and used for the in-situ upgrading process of heavy crude oil (viscosity 2157 mPa·s, and API gravity of 14.1° at 25 °C) in aquathermolysis conditions for viscosity reduction and heavy oil recovery. All characterizations of the obtained nanoparticles catalysts (NixOx) were performed through Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), X-Ray and Diffraction (XRD), and ASAP 2400 analyzer from Micromeritics (USA), methods. Experiments of catalytic and non-catalytic upgrading processes were carried out in a discontinuous reactor at a temperature of 300 °C and 72 bars for 24 h and 2% of catalyst ratio to the total weight of heavy crude oil. XRD analysis revealed that the use of nanoparticles of NiO significantly participated in the upgrading processes (by desulfurization) where different activated form catalysts were observed, such as α-NiS, β-NiS, Ni3S4, Ni9S8, and NiO. The results of viscosity analysis, elemental analysis, and 13C NMR analysis revealed that the viscosity of heavy crude oil decreased from 2157 to 800 mPa·s, heteroatoms removal from heavy oil ranged from S-4.28% to 3.32% and N-0.40% to 0.37%, and total content of fractions (ΣC8-C25) increased from 59.56% to a maximum of 72.21%, with catalyst-3 thank to isomerization of normal and cyclo-alkanes and dealkylation of lateral chains of aromatics structures, respectively. Moreover, the obtained nanoparticles showed good selectivity, promoting in-situ hydrogenation-dehydrogenation reactions, and hydrogen redistribution over carbons (H/C) is improved, ranging from 1.48 to a maximum of 1.77 in sample catalyst-3. On the other hand, the use of nanoparticle catalysts have also impacted the hydrogen production, where the H2/CO provided from the water gas shift reaction has increased. Nickel oxide catalysts have the potential for in-situ hydrothermal upgrading of heavy crude oil because of their great potential to catalyze the aquathermolysis reactions in the presence of steam.

Experimental Study on the Enhanced Oil Recovery Mechanism of an Ordinary Heavy Oil Field by Polymer Flooding.

It is widely known that in the water flooding development process of ordinary heavy oil, the fingering phenomenon is obvious, there are a lot of unswept areas, and absolutely, the recovery is really very low. In addition, for some shallow and thin ordinary heavy oil reservoirs limited by the geological conditions of the reservoir, the thermal recovery technology also has serious heat loss and high development cost. Therefore, there is an urgent need to transform the development and further improve the enhanced oil recovery (EOR). In this paper, the mechanism of EOR by polymer flooding was investigated for high-porosity and high-permeability terrestrial ordinary heavy oil reservoirs. Through laboratory experiments, we analyzed the characteristics of oil-water relative permeability curves, mobility control ability, and microscopic seepage characteristics during polymer flooding of ordinary heavy oil reservoirs. On this basis, the effect of the mobility ratio on seepage characteristics and the mechanism of EOR enhancement were clarified. The results show that the polymer can effectively improve the mobility control effect of the displacing fluid. As the polymer solution and ordinary heavy oil have the characteristics of high viscosity and low mobility, there is a minimum mobility ratio in the process of polymer flooding. Namely, the characteristics of dual low mobility exist in the process of polymer flooding for the ordinary heavy oil. It effectively enhances the profile control and plugging ability of the polymer, thus expanding the sweep volume of larger pores and improving the displacement efficiency of smaller pores. Based on the two factors mentioned above, it is found that the dual low mobility characteristics can improve the recovery of ordinary heavy oil by polymer flooding. Therefore, it is proposed that an enhanced profile control and plugging effect due to the dual low mobility characteristics is an important EOR mechanism for ordinary heavy oil development by polymer flooding.

Rheological characterization and shear viscosity prediction of heavy oil-in-water emulsions

The rheology of oil-in-water emulsion is a key issues in heavy oil development, storage, transport, and processing. Based on single-factor experiments, the effect of shear rate (γ), dispersed-phase volume fraction (φ), continuous-phase viscosity (ηc), and droplet size (D50) on the rheological properties of heavy oil-in-water emulsions were evaluated through microscopic observation and rheological experiments. Furthermore, a 10-factor/3-level experiment was designed to investigate the sensitive factors affecting shear viscosity. The experimental results indicated that, when the volume fraction of dispersed-phase was higher than 0.3, the rheological characteristics of the prepared emulsions exhibited an obvious shear-thinning behavior, and the droplet size had a significant influence on shear viscosity at shear rates between 0.3 and 100 s−1. When the volume fraction of the dispersed-phase was less than 0.3, the emulsions behaved as Newtonian liquids. As the shear rates increase, the droplets disperse to a greater extent, leading a reduction in viscosity, and ultimately causing the emulsion to exhibit the characteristics of a Newtonian fluid. Owing to the strong hydration effect of small droplets, the viscosity of small droplet-size emulsions increases at a constant dispersed-phase volume fraction. Emulsions exhibit obvious shear-thinning behavior with an increase in shear rate, as a result of a low effective dispersed-phase volume fraction under a high shear rate. Finally, the volume coefficient of the Sibree model was corrected by considering correlation factors from the experiments, and the Sibree model was improved. The improved shear viscosity model better fits the experimental data for all the studied heavy oil-in-water emulsion, with the mean relative error of 9.3%. Therefore, the improved model can predict the effects of all factors affecting shear viscosity.

High-Viscosity Crude Oil. A Review

The current problem of the production and processing of heavy high-viscosity oils in Ukraine and the world has been considered. It has been established that the main reserves of heavy high-viscosity crude oils in the world are located in South and North America, in the Middle East, as well as in Ukraine in the eastern regions. An analysis of various classifications of heavy high-viscosity oils, which are used both in Ukraine and in the world, was carried out. The main extraction methods of heavy high-viscosity oils were considered, in particular, quarry, mine, and well extraction methods. An overview of the technological processes of heavy high-viscosity oil processing was carried out.

Innovations in Oil Processing: Chemical Transformation of Oil Components through Ultrasound Assistance

The present review paper discusses the different aspects related to the chemical transformation of oil components through ultrasound assistance. Ultrasound intensifies heat and mass transfer processes in oil production and treatment, which is used to separate water–oil emulsions, optimize pumping, clean the bottomhole zone, and more. The main reason for the positive effect of ultrasound is the cavitation phenomenon, which forms vapor–gas bubbles that cause changes in the structure and properties of dispersed phases, intensifying processes such as dissolution, extraction, and emulsification. The inhomogeneities in the medium being processed also reduce resistance to bubble formation and increase the intensity of technological processes. It is believed that ultrasonic treatment of heavy oil influences the colloid structure of oil. Such effects were observed in several studies. Despite the widespread use of ultrasound in oil processing, the chemical transformation of hydrocarbons during ultrasonic treatment remains an understudied area, particularly for heavy oil. Furthermore, the transformation mechanism of high-molecular-weight fragments of oil under ultrasonic energy is still poorly understood. Heavy oil can benefit greatly from ultrasonic treatment, both after production for pipeline transportation or plant processing and in the reservoir. This is due to the improved mobility of oil in rock and the chemical transformation of high-molecular components, such as resins, asphaltenes, and paraffins. These transformations contribute to the overall improvement of heavy oil processing, making it a crucial area for further research and development. In this review paper, we will explore the latest innovations in oil processing, specifically focusing on the chemical transformation of oil components through ultrasound assistance. This will include a comprehensive analysis of the underlying mechanisms of ultrasonic treatment and their impact on the chemical composition of oil. The review will also include a discussion of the current state of the art and future directions for research in this field, highlighting the potential for further advancements in the use of ultrasound in oil processing.

Processing of heavy high-viscosity oil mixtures from the eastern region of Ukraine: technological aspects

The article presents an analysis of reserves and processing of heavy high-viscosity crude oils in Ukraine and the world. A study of the physicochemical properties of heavy high-viscosity oils from the Yablunivske field, Poltava region of Ukraine, taken from various wells was conducted. For further research in order to develop a basic manufacturing scheme for the processing of heavy high-viscosity oils, a mixture of heavy high-viscosity oils from the Yablunivske field was used in certain ratios and its physicochemical properties were determined. As a result of the vacuum distillation of a mixture of heavy high-viscosity oils, the following products were obtained: broad gasoline fraction (fraction boiled up to 2000C), broad diesel fraction (fraction 200–3600C) and the rest of the process (fraction >3600C). An analysis of the physicochemical properties of the prepared fractions was also carried out. It was established that the products obtained from the mixture of heavy high-viscosity oils of the Yablunivske field can be used as raw materials for the production of commercial gasoline and diesel fuels. The rest of the process can serve as raw materials for the production of road bitumen. According to the analysis of the physicochemical properties of the products obtained by vacuum distillation of a mixture of heavy high-viscosity oils, the basics of the processing technology of a mixture of heavy high-viscosity oils of the Yablunivske field were developed. In particular, a manufacturing scheme and a flow chart of the process were proposed, and the material balance was calculated.

Changes in the Composition of Heavy Oil and the Structure of Asphaltenes upon Treatment with Isopropyl Alcohol

The interactions of the components of heavy oil from the Zyuzeevskoye field (Republic of Tatarstan) and isopropyl alcohol (IPA) at temperatures of 25, 65, and 100°C were studied. It was established that the temperature regime affected the density, composition, and structural group characteristics of the products of interactions between the oil and IPA. The density of the resulting products increased by 4 wt % (from 0.885 to 0.924 g/cm3) as the process temperature was increased to 100°C, and the concentration of resin–asphaltene substances also increased by 4 wt % in this case. It was shown using IR spectroscopy that the tentative concentration of paraffin fragments in the structure of asphaltenes increased significantly when the oil was treated with isopropanol at temperatures of 65–100°C, and the branching factor increased by a factor of 3, as compared to that of the initial asphaltenes. The observed changes were due to the incorporation of isopropyl fragments into the structure of asphaltene molecules upon the processing of heavy oil with IPA.

Numerical Analysis and Experiments on Heavy Oil Heating of Shipwrecks

Analyze the change of oil temperature flow times during the heating process of wreck heavy oil and the temperature gradient change in the radiation area of the heating source. Using the result guide the heating process of low-temperature underwater oil recovery operations on the wreck. fluid software was used for the analysis process of the numerical simulation, and the physical model test is a simulation test of low temperature underwater electromagnetic heating of heavy oil. In this way, data related to the heating process of heavy oil can be obtained. from the numerical analysis results and the physical model test results, it can be concluded that the numerical simulation results are similar to the experimental verification results. The result can be used for engineering guidance. Due to the physical properties of heavy oil, the oil temperature decays faster during the heating process and the radiation effect of heat source is small, using the electromagnetic heater heats the heavy oil in the oil tank, and the heavy oil can be heated to meet the requirements of the pumping operation in a short time. The calculation model parameters are derived from actual operations. Numerical calculations and physical test results are of great significance to engineering guidance and can guide the underwater cryogenic oil pumping operation of shipwrecks.

Strategies for adding tetralin in thermal processing of heavy oil

The strategy of adding tetralin as a H-donor in the thermal processing of heavy oil was investigated by experimental characterization and theoretical calculations. According to the experiments, the timing of adding 1 wt% of tetralin has a great influence on the visbreaking performance of heavy oil. Calculations based on density functional theory showed that benzyl radicals released from the thermal cracking of tetralin accelerate the dealkylation that determines the heavy oil upgrading. Meanwhile, Hα provided by tetralin is able to selectively saturate aromatic C radicals which are essential for condensation. Compared with the conventional H-donor addition, i.e., pre-mixing of tetralin with heavy oil, a similar viscosity reduction rate of about 98% can be obtained during the visbreaking with delayed tetralin addition. Furthermore, the addition of tetralin before the significant occurrence of condensation further increases the conversion of vacuum residue fraction by 3.4% and reduces the asphaltene content of the product by 2.6 wt%.

Глубокая переработка гудрона на базе комплекса глубокой переработки тяжелых остатков АО «ТАИФ-НК»

The article is devoted to the processing of vacuum residue and vacuum gasoil based on the Veba Combi Cracking (VCC) technology and covers aspects of the formation of the process from the first research in the field of coal hydrocracking to the world's largest complex for deep processing of heavy oil refining residues of TAIF-NK JSC.

Исследование термического превращения мазута в присутствии регенерированного отработанного катализатора гидроочистки

An urgent task of the oil refining industry is the development of a thermodestructive process for the processing of heavy oil residues. This paper presents the results of a study of thermal cracking of fuel oil in the presence of aluminocobaltmolybdenum regenerated spent hydrotreating catalyst. The experiments were carried out using an autoclave, as well as using a number of instrumental methods of analysis. The effect of the degree of dispersity and catalyst content on the results of the process under study was studied. The material balance of the thermal cracking process in the presence of catalyst samples of different fractional composition is compared with the material balance of thermal cracking in the temperature range of 450-470 °C. The physical and chemical properties of the samples of catalysts, raw materials and products of the process were determined. The analysis of the obtained experimental data was carried out, the conditions for the most efficient processing of raw materials in the process of thermal cracking in the presence of a catalyst were determined, and conclusions were drawn about the prospects for its use for processing heavy oil residues.

Возможность получения перспективных дорожных битумов марок PG в условиях реализации проекта строительства установки ЭЛОУ-АВТ-6 ПАО АНК «Башнефть» «Башнефть-Уфанефтехим»

The article investigates possible options for processing heavy oils entering refineries separately or when they are processed together with the oils of West Siberian deposits according to the bitumen profile. It is shown that the production of demanded unmodified grades of road bitumen PG 64-28 and PG 58-34 according to GOST R 58400.1 in the conditions of weighting of crude oil during the implementation of the ELOU-AVT-6 installation project at Bashneft-Ufaneftekhim, it is possible if measures are taken to compensate for the deficit in paraffin-naphthenic and aromatic compounds. For the production of these PG grades, an increased introduction of the TVG of this installation is required (from 25 to 40 %), however, it will not require the use of the TVG from AVT, which are in demand for oil production, processing mainly oil from West Siberian fields, or plasticizing components from the oil production complex (selective purification extracts).

The effect of chlorella hydrothermal products on the heavy oil upgrading process

In-situ upgrading can improve the scale of heavy oil development, but the efficiency of in-situ hydrothermal hydrogen supply is limited. In this paper, the combination of algae hydrothermal liquefaction and heavy oil upgrading and viscosity reduction process is proposed. The liquefaction products of hydrothermal liquefaction are used to supply hydrogen to the heavy oil upgrading and viscosity reduction process, thereby enriching the supply path of active hydrogen. The effects of hydrothermal liquefaction temperature of Chlorella and the addition of 5% Fe/HZSM-5 catalyst on the liquefaction rate and product distribution of Chlorella were investigated, and the upgrading and viscosity reduction process of heavy oil with the participation of hydrothermal liquefaction products was discussed. The results show that when the temperature of upgraded heavy oil is 280 °C and 5 wt% of hydrothermal liquefaction products are added and reacted for 24 h can make the viscosity reduction rate of heavy oil reach 84.32%, and 31.2% of resin in heavy oil was converted into aromatic hydrocarbon. Elemental analysis showed that the upgraded heavy oil H/C ratio increased, and GC–MS analysis showed that the distribution of algae hydrothermal liquefaction products could be adjusted by the catalyst, and more aromatics were produced after the addition of the catalyst, which confirmed that the aromatics in hydrothermal liquefaction products had a significant effect on the quality improvement and viscosity reduction of heavy oil. Its molecular weight was also found to be reduced from 853 to 326 in the average molecular weight test (GPC). The efficient carbon sequestration of algae is combined with the demand for carbon dioxide emission reduction in oilfields to realize the recycling of carbon resources.

A novel strategy to improve steam heat utilization and reduce carbon emissions during heavy oil development

In recent years, the green transformation of the traditional energy industry and the reduction of carbon emissions have attracted widespread societal attention. In the thermal recovery process of heavy oil, the low heat utilization rate has always been the bottleneck restricting its production. In addition, the associated flue gas emissions also pose a considerable challenge to environmental protection. In this paper, flue gas and SiO2 aerogel were jointly applied to reduce steam heat loss while achieving exhaust gas sequestration. Condensation heat transfer experiments were carried out to explore the mechanism of the two affecting the heat dissipation process of steam liquefaction. A series of displacement experiments with different injection methods in a one-dimensional sandpack were performed to select combinations of developing heavy oil with high efficiency and low carbon. By detecting the temperature changes of the model and calculating the final storage volume, the effects of promoting steam chamber expansion and flue gas sequestration were evaluated. The results showed that the aerogel adsorption layer could change the wettability of the condensing surface, thereby showing the characteristics of film condensation. Flue gas molecules could be captured by aerogel nanofluids, further exerting a synergistic thermal insulation effect, and the temperature of the deep reservoir increased by 7.7 °C. Simultaneously, the crude oil recovery increased by 8.8% compared with pure steam flooding. Moreover, the numerous nanoparticle-stabilized foams generated via this method were noted as an essential way to sequester carbon in a high water-cut formation, and the final sequestration rate reached 77.4%.

Comparative analysis of the effects of hydrogen and formic acid on the vacuum residue hydrocracking

The improvement of the existing technologies aimed at deeper processing of heavy oils and oil residues and development of new ones is an urgent task of modern oil refining. Experiments in a flow installation using a quartz reactor were performed to determine the formic acid decomposition pathway. The experiments showed that the formic acid decomposition over the Ni-Mo/Al2O3 catalyst predominantly yielded hydrogen and CO2. Therefore, in this study comparative experiments on the effects of hydrogen and formic acid on the vacuum residue hydrocracking in the presence of the Ni-Mo/Y-Al2O3 and Ni-Mo/Al2O3 catalysts were performed at 375–400 °C and 0.45 MPa pressure. The concentration of hydrogen or formic acid in argon was 10 vol%. The catalysts were prepared by impregnation of the corresponding supports with the aqueous solution obtained using nickel hydroxide, ammonium heptamolybdate and citric acid. Electron microscopy and XRD studies of the Ni-Mo/Y-Al2O3 and Ni-Mo/Al2O3 catalysts demonstrated that the active component in the studied catalysts was in a finely dispersed state. The size of Ni-Mo particles was 0.4–0.6 nm in the Ni-Mo/Y-Al2O3 catalyst and 0.3–0.6 nm in Ni-Mo/Al2O3. For both catalysts Ni-Mo/Y-Al2O3 and Ni-Mo/Al2O3 higher vacuum residue conversion to liquid products was observed in the presence of formic acid than in the presence of hydrogen. Hydrogen substitution for formic acid vapor during the vacuum residue hydrocracking also results in the lower sulfur content in the liquid reaction products. The use of formic acid as a hydrogen donor significantly simplifies the process hydrocracking.

Catalytic capacity evolution of montmorillonite in in-situ combustion of heavy oil

Clay minerals such as montmorillonite are significant in petroleum storage and recovery. Montmorillonite (Mt) is a natural solid acid catalyst containing Brønsted and Lewis acid sites and can catalyze heavy oil oxidation (HOO) during in-situ combustion (ISC). However, its catalytic activity largely depends on the heating process of heavy oil. In the study, the catalytic capacity evolution of Mt in ISC of heavy oil was explored with the isoconversional method and thermal analysis. In low-temperature oxidation (LTO) and high-temperature oxidation (HTO) stages, the addition of Mt largely reduced the peak temperatures (Tpeak) of DTA and DTG and the Tpeak of H2O (LTO and HTO stages) and CO2 (HTO stage) in HOO. Notably, Mt did not always show the positive catalytic effect. In LTO stage, the thermal transformation process had a small effect on DTA Tpeak, Tpeak of H2O and CO2, and the reaction activation energy (Eα) of HOO. In HTO stage, the catalytic effect of Mt on HOO was related to its thermal transformation process, especially interlayer water (IW) dehydration and dehydroxylation. In HTO stage, the IW dehydration process of Mt showed the strongest catalytic effect on HOO, significantly reduced DTA Tpeak and Eα, and resulted in the lowest Tpeak of H2O and CO2. The dehydroxylation process of Mt also showed a certain effect, whereas the overlapping process between the dehydration (IW) reaction and partial dehydroxylation reaction of Mt had no positive catalytic effect on HOO. DTA, TG-FTIR, and non-isothermal kinetic analysis further confirmed that the catalytic capacity of Mt in HTO stage was improved by IW dehydration process of Mt and weakened by the dehydroxylation process of Mt.

A Theoretical and Experimental Approach to the Analysis of Hydrogen Generation and Thermodynamic Behavior in an In Situ Heavy Oil Upgrading Process Using Oil-Based Nanofluids

This study aims to show a theoretical and experimental approach to the analysis of hydrogen generation and its thermodynamic behavior in an in situ upgrading process of heavy crude oil using nanotechnology. Two nanoparticles of different chemical natures (ceria and alumina) were evaluated in asphaltene adsorption/decomposition under a steam atmosphere. Then, a nanofluid containing 500 mg·L−1 of the best-performing nanoparticles on a light hydrocarbon was formulated and injected in a dispersed form in the steam stream during steam injection recovery tests of two Colombian heavy crude oils (HO1 and HO2). The nanoparticles increased the oil recovery by 27% and 39% for HO1 and HO2 regarding the steam injection. The oil recovery at the end of the displacement test was 85% and 91% for HO1 and HO2, respectively. The recovered crude oil showed an increment in API° gravity from 12.4° and 12.1° to 18.5° and 29.2° for HO1 and HO2, respectively. Other properties, such as viscosity and content of asphaltenes and resins with high molecular weight, were positively modified in both crude oils. The fugacity of H2 was determined between the reservoir and overburden pressure and different temperatures, which were determined by the thermal profiles in the displacement test. The fugacity was calculated using the application of virial equations of state with mixing rules based on the possible intermolecular interactions between the components. Hydrogen acquired a higher chemical potential via nanoparticle presence. However, the difference in H2 fugacity between both points is much higher with nanoparticles, which means that hydrogen presents a lower tendency to migrate by diffusion to the high-pressure point. The difference between HO1 and HO2 lies mainly in the fact that the pressure difference between the reservoir and the overburden pressure is greater in HO2; therefore, the difference in fugacity is greater when the pressure differential is greater.

A semi-compositional approach to model asphaltene precipitation and deposition in solvent-based bitumen recovery processes

Steam assisted gravity drainage (SAGD), as a commercially proven high ultimate recovery process for heavy oil and bitumen is energy intensive and may be limited by high usage of water. In the recent years, numerous methods to combine solvent and heat have been proposed for the in-situ recovery of bitumen. Among these methods, N-Solv (heated solvent vapor injection) and EBRT (enhanced bitumen recovery technology) utilize heated solvent vapor to extract heavy crudes under in situ conditions. These methods take the advantage of partial in situ upgrading of oil with much lower consumptions of water and natural gas and have the potential to reduce greenhouse gas (GHG) emissions. However, with the current knowledge relevant to solvent/heat-assisted recovery processes, it still remained uncertain how the in-situ upgrading could impact ultimate recovery and the efficiency of these processes. This study, thus, aims at providing insights about these processes with a numerical model. The study develops a simulation model that captures important mechanisms involved in the processes such as diffusion/dispersion, solvent dissolution, asphaltene precipitation and potential deposition. The complexity of modelling such processes is due to interrelation of oil–gas phase behavior and fluid transport mechanisms combined with in situ upgrading of oil. The intention is not to only identify factors important to the modeling of these processes, but also find how robust simulation models can be developed to replicate observed field behavior. A semi-compositional approach, based on liquid–liquid equilibrium, is proposed to properly capture the asphaltene precipitation in thermal numerical simulators using direct lab measured data. Our analysis will be presented regarding upgrading mechanisms that should be implemented, their effect on the oil production rate, and techniques to model them.

Low-Temperature Oxidation of Heavy Oil Asphaltene with and without Catalyst.

In this study, the asphaltene extracted from Luntai heavy oil was oxidized by a mixture of propionic anhydride and hydrogen peroxide without and with a catalyst. Elemental analysis and infrared spectroscopy results indicated the occurrence of oxygen addition, condensation, and side chain cleavage reactions in the oxidation process. Oxidation products were divided into methanol solubles and methanol insolubles. The H/C and O/C atomic ratios of the MeOHS in the oxidation products without a catalyst were higher than those of the Luntai asphaltene. MeOHS had fewer aromatic rings than Luntai asphaltene. Compared with the oxidative reaction without a catalyst, the total mass of oxidation products and the proportion of MeOHS in oxidation products both increased after catalytic oxidation. This low-temperature oxidation technology can be used to upgrade asphaltenes, and thus can promote the exploitation and processing of heavy oil.