Steam Injection Process Research Articles

Well-Placement Optimization in Heavy Oil Reservoirs Using a Novel Method of In Situ Steam Generation

Determination of optimal well locations plays an important role in the efficient recovery of hydrocarbon resources. However, it is a challenging and complex task. The objective of this paper is to determine the optimal well locations in a heavy oil reservoir under production using a novel recovery process in which steam is generated, in situ, using thermochemical reactions. Self-adaptive differential evolution (SaDE) and particle swarm optimization (PSO) methods are used as the global optimizer to find the optimal configuration of wells that will yield the highest net present value (NPV). This is the first known application, where SaDE and PSO methods are used to optimize well locations in a heavy oil reservoir that is recovered by injecting steam generated in situ using thermo-chemical reactions. Comparison analysis between the two proposed optimization techniques is introduced. On the other hand, laboratory experiments were performed to confirm the heavy oil production by thermochemical means. CMG STARS simulator is utilized to simulate reservoir models with different well configurations. The experimental results showed that thermochemicals, such as ammonium chloride along with sodium nitrate, can be used to generate in situ thermal energy, which efficiently reduces heavy-oil viscosity. Comparison of results is made between the NPV achieved by the well configuration proposed by the SaDE and PSO methods. The results showed that the optimization using SaDE resulted in 15% increase in the NPV compared to that of the PSO after 10 years of production under in situ steam injection process using thermochemical reactions.

Metabolic effects in mice of cream processing: Direct ultra-high-temperature process lowers high-fat-induced adipose tissue inflammation

Although UHT heat treatment is being optimized to improve the stability and functional properties of dairy products, its metabolic effects remain scarcely known. As such, we studied the effect of the type of UHT process on lipid metabolism, intestinal barrier, and inflammation in mice. Nine-week-old male C57Bl/6J mice were fed a diet composed of nonlipidic powder mixed with different UHT dairy creams (final: 13% milkfat) for 1 or 4 wk. All creams contained 0.02% of thickener (carrageenan) and were treated via either (1) classical indirect heating process (Th), (2) indirect process at higher temperature (Th+), or (3) direct process by steam injection (ThD). Plasma, epididymal adipose tissue (EAT), and intestine were analyzed. Multivariate principal component analyses were used to identify differential effects of processes. Th+ differed by a globally higher liver damage score compared with that of the other creams. After 4 wk, the duodenal expression of lipid absorption genes fatty acid binding protein 4 (Fatp4) and microsomal triglycerides transfer protein (Mttp) was lower in the Th+ versus Th group. Expression in the colon of tight junction protein zonula occludens 1 (Zo1) and of some endoplasmic reticulum stress markers was lower in both Th+ and ThD versus the Th group. In EAT, ThD had lower gene expression of several inflammatory markers after 4 wk. Some differential effects may be related to heat-induced physicochemical changes of creams. The type of cream UHT process differentially affected metabolic parameters in mice after a 4-wk fat-rich diet, partly due to cream structure. Altogether, direct steam injection process induced the lowest early markers of high-fat-induced metabolic inflammation in EAT.

Reduction of ochratoxin A in direct steam injected oat-based infant cereals with baking soda

Ochratoxin A (OTA) is a possible human carcinogen with its potent nephrotoxicity and has been found in many agricultural commodities particularly in oats and its processed foods including oat-based infant cereals. While OTA is stable under most thermal processing conditions, alkaline pH can increase the reduction of OTA. In this study, the effect of direct steam injection (DSI) process along with the absence and presence baking soda (0.5% and 1% of solid contents) on the reduction of OTA in oat-based infant cereals was investigated. Food-grade oat flour was spiked with OTA (100 μg/kg) and equilibrated overnight followed by preparation of slurry by adding water to reach 5% solid content. Then the slurry was processed by DSI at 85 °C and 121 °C followed by spray drying at 210 °C. Greater reduction of OTA in DSI processed oat-based infant cereals was observed at higher process temperature to result in 20–28% reduction. In addition, the reduction of OTA increased with increasing amounts of baking soda. These results suggest that OTA may be reduced significantly by DSI process, which can be applied to commercial production of oat-based infant cereals. Baking soda may also help to reduce OTA amount in cereal-based infant cereals during thermal processing.

A coupled model for CO2 & superheated steam flow in full-length concentric dual-tube horizontal wells to predict the thermophysical properties of CO2 & superheated steam mixture considering condensation

The mixture of CO2 and superheated steam (SHS) has been proved effective for heavy oil recovery by field practices. It has been proved that the development effect is closely related to the state parameters (temperature, pressure and superheated degree etc.) of the mixture. As a result, wellbore modeling is an important branch in the study of thermal recovery of heavy oil. In recent years, concentric dual-tube wells (CDTW) coupled with multi-point injection technique (MPIT) is proposed to overcome the fingering phenomenon, induced by serious reservoir heterogeneity, during the steam injection process. In this paper, a wellbore model is developed for simulating CO2 & SHS flow in a full-length CDTW. The model is solved with finite difference method on space. It is found that: (a) An injection pressure, higher than 4.1 MPa, in the integral joint tube (IJT) or an injection pressure, smaller than 4.1 MPa, in annuli are recommended to obtain a uniform steam absorption rate along the horizontal wellbores. (b) The mass injection rate at well-head condition should be close to each other to avoid un-uniform of steam absorption rate along the horizontal wellbores. (c) When phase change occurs in the annuli, the mixture temperature increases with increasing CO2 content. (d) The total length of wet steam flow in the horizontal section of the wellbores increases with increasing CO2 content.

Heavy Oil Upgrading and Enhanced Recovery in a Steam Injection Process Assisted by NiO- and PdO-Functionalized SiO2 Nanoparticulated Catalysts

This work aims to investigate the effect of active catalytic nanoparticles on the improvement of the efficiency in recovery of a continuous steam injection process. Catalytic nanoparticles were selected through batch-adsorption experiments and the subsequent evaluation of the temperature for catalytic steam gasification in a thermogravimetric analyzer. A nanoparticulated SiO2 support was functionalized with 1.0 wt % of NiO and PdO nanocrystals, respectively, to improve the catalytic activity of the nanoparticles. Oil recovery was evaluated using a sand pack in steam injection scenarios in the absence and presence of a 500 mg/L SiNi1Pd1 nanoparticles-based nanofluid. The displacement test was carried out by constructing the base curves with water injection followed by steam injection in the absence and presence of the prepared treatment. The oil recovery increased 56% after steam injection with nanoparticles in comparison with the steam injection in the absence of the catalysts. The API gravity increases from 7.2° to 12.1°. Changes in the asphaltenes fraction corroborated the catalytic effect of the nanoparticles by reducing the asphaltenes content and the 620 °C+ residue 40% and 47%, respectively. Also, rheological measurements showed that the viscosity decreased by up to 85% (one order of magnitude) after the nanofluid treatment during the steam injection process.

Energy efficiency and greenhouse gas emissions of current steam injection process and promising steam based techniques for heavy oil reservoirs

Steam injection process has been the prevailing technique for heavy oil and bitumen extraction in the past decades, but the recovery performance and energy efficiency are poor, especially in oil reservoirs with harsh conditions and severe heterogeneity. With global requirements on energy conservation and emission reduction, it is of great significance to improve current techniques or find new techniques to promote the energy efficiency of steam injection process and mitigate associated greenhouse gas emissions. In this study, the energy efficiency and CO2 emissions of current steam injection processes were evaluated, along with sensitivity analysis of various influencing factors. Cyclic steam stimulation (CSS) process was taken as an example to study the production and energy efficiency performance of steam injection. The results show that the steam to oil ratio, energy intensity and CO2 emissions all rise with the increasing crude oil viscosity, but fall with the increase of oil saturation, reservoir temperature, bottom hole steam quality and reservoir heat efficiency. Field history analysis about CSS process shows that the production performance of CSS process was dominated by different factors with the proceeding of oil production, and gas injection assisted CSS process can effectively enhance oil recovery, improve energy efficiency and mitigate CO2 emissions. Finally, the improved steam injection techniques are discussed to shed some lights on the efficient exploitation of heavy oil reservoirs.

Experimental study of the steam distillation mechanism during the steam injection process for heavy oil recovery

Steam distillation can effectively enhance heavy oil recovery during steam injection process in heavy oil reservoirs. However, the mechanism of steam distillation is complex, and the changes in oil properties during distillation remain unclear. In this study, three comparative steam distillation experiments were designed and conducted, including distillation processes employing saturated steam, steam superheated by 10 °C, and steam superheated by 40 °C. Heavy oil samples were derived from the Jin-1 Block in a typical heavy oilfield, in China. The density, viscosity, SARA fractions, and carbon number distribution of the residual oil were compared to those obtained before conducting steam distillation experiments. The steam distillation rates obtained with steam superheated by 40 °C, steam superheated by 10 °C, and saturated steam were 11.158%, 10.903% and 10.423%, respectively. The results indicate that the steam distillation rate of heavy oil increases significantly with increasing degree of superheating. During the steam distillation process, the density and viscosity of residual oil increase, the contents of saturated hydrocarbons and resin decrease, and the contents of aromatic hydrocarbons and asphaltenes increase. In addition, analysis of the distilled components indicates that lightweight components with smaller carbon numbers are removed firstly by steam distillation, followed by heavier components with larger carbon numbers. Moreover, all hydrocarbons with carbon numbers less than C22 are removed from heavy oil in the distillation process, while the maximum carbon number of the distilled components was C34. This study is favorable for understanding the changes in the properties of residual oil after distillation during the steam injection process for heavy oil recovery.

Improved Monitoring System for Heavy-Oil Steam-Assisted-Gravity-Drainage Wells

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 187441, “Improved Monitoring System for Heavy-Oil Steam-Assisted-Gravity-Drainage Wells,” by Christopher Baldwin, Weatherford, prepared for the 2017 SPE Annual Technical Conference and Exhibition, San Antonio, Texas, USA, 8–11 October. The paper has not been peer reviewed. The complete paper provides an overview of the development of fiber-optic sensing for steam-assisted-gravity-drainage (SAGD) applications, including a review of more than 10 years of work in development and field applications in western Canada. Information provided in this paper is applicable beyond SAGD applications. The fiber-optic monitoring systems might also be used for intelligent, subsea, and unconventional wells. Introduction One area that has benefited from the unique advantages of fiber-optic sensing is thermal monitoring of SAGD wells. One particular fiber-optic technology that has proved successful in these thermal-monitoring applications is wavelength-domain multiplexing of Bragg-grating-based fiber-optic sensors. Commonly referred to as array temperature sensing (ATS), the Bragg-grating arrays can be manufactured splice-free for long-term reliability. The number of thermal sensing points can range from a few to well over 100 for a single cable. Each Bragg-grating sensing point provides a real-time, accurate measurement of temperature at that location along the wellbore. ATS systems have been used successfully to monitor the steam-injection and production processes in SAGD wells. ATS systems are capable of performing more-accurate temperature measurements and are able to resolve much smaller temperature features compared with distributed temperature sensing (DTS). Bragg-grating optical sensors not only provide temperature measurements but also can be packaged in a transducer to provide pressure and temperature (PT) also can be packaged in a transducer to provide pressure and temperature (PT) readings. The optical PT gauge is compatible with the surface instrumentation that records the ATS responses, allowing for the PT gauge to be integrated at the end of the ATS optical fiber for single-wellhead penetration, providing multiplexed DTS and PT measurements. Environmental Effects on Downhole Fiber-Optic Sensors The requirements for a successful monitoring system in SAGD applications are dictated by the harsh environments experienced downhole. In the past, the presence of hydrogen in these applications has caused issues with various fiber-optic sensing technologies. Improvements in optical-fiber design and downhole cable construction have helped to mitigate some of these issues, but any downhole monitoring system must be able to cope with the presence of hydrogen in relatively high-temperature environments.

Effect of Fe2O3 and WO3 nanoparticle on steam injection recovery

ABSTRACTNanotechnology has the potential to introduce revolutionary changes in several areas of oil and gas industry. In this paper, the effect of different concentrations of Fe2O3 and WO3 nanoparticles at various temperatures was studied on viscosity of heavy oils. The effect of Fe2O3 and WO3 nanoparticles mixture on steam injection process is studied. The experimental tests show that some of these nanoparticles decrease the heavy oil viscosity to less than 40% in certain concentration at different temperatures. Our results of steam injection tests show that the injection of Fe2O3 and WO3 nanoparticles mixture increases the heavy oil recovery.

Emulsification and improved oil recovery with viscosity reducer during steam injection process for heavy oil

An anionic–nonionic surfactant was proposed as viscosity reducer (VR) for study. Firstly, bulk emulsion behavior was investigated to optimize the emulsification process. Secondly, core flooding tests were carried out to evaluate the synergistic effect of VR and steam for improved heavy oil recovery, as well as emulsion properties along the distance. Thirdly, a 2D microvisual study was performed to illustrate emulsion migration and plug property in porous media. Finally, VR assisted steam stimulation was conducted for field application, and gained satisfactory result both in oil–steam ratio and oil recovery, providing an alternative for enhancing oil recovery in similar steamflooded reservoirs.

Hybrid steam/solvent wellbore design for an optimal operation

To have an efficient oil recovery in hybrid steam-solvent injection, the solvent must condense at the steam chamber edge. Thus, the injection well must deliver the solvent near its dew point at the sand face. This paper presents a sensitivity analysis to study how different operational parameters and well design affect the behaviour of steam and solvent along the wellbore before reaching the perforation intervals. This study highlights the importance of wellbore modelling in the solvent assisted steam injection process. Results show that with some specific operational parameters and solvent composition, up to 23% of the solvent condense along the wellbore before reaching the sand face, meaning that only 77% of the solvent mixture effectively is used for the heavy oil recovery. Also, in a case study, it was shown that using 2 7/8 inch tubing instead of a 3 1/2 inch leads to a temperature improvement of 54°F. [Received: December 16, 2016; Accepted: June 18, 2017]

Hybrid steam/solvent wellbore design for an optimal operation

To have an efficient oil recovery in hybrid steam-solvent injection, the solvent must condense at the steam chamber edge. Thus, the injection well must deliver the solvent near its dew point at the sand face. This paper presents a sensitivity analysis to study how different operational parameters and well design affect the behaviour of steam and solvent along the wellbore before reaching the perforation intervals. This study highlights the importance of wellbore modelling in the solvent assisted steam injection process. Results show that with some specific operational parameters and solvent composition, up to 23% of the solvent condense along the wellbore before reaching the sand face, meaning that only 77% of the solvent mixture effectively is used for the heavy oil recovery. Also, in a case study, it was shown that using 2 7/8 inch tubing instead of a 3 1/2 inch leads to a temperature improvement of 54°F. [Received: December 16, 2016; Accepted: June 18, 2017]

A multi-featured model for estimation of thermodynamic properties, adiabatic flame temperature and equilibrium combustion products of fuels, fuel blends, surrogates and fuel additives

This study introduces a new multi-featured equilibrium combustion model for fuels, fuel blends and surrogates which estimates mole fractions, adiabatic flame temperature and thermodynamic properties of the equilibrium combustion products. The model enables simultaneous consideration of unlimited number of CαHβOγNδ type fuels of different ratios and also enables any CαHβOγNδ type fuel additive, Argon, H2O, CO, CO2, N2, and O2 to be considered among the reactants. Equilibrium mole fractions and adiabatic flame temperature are not only necessary for estimating thermodynamic properties of exhaust gases but also provide key data to obtain the non-equilibrium concentrations. As for thermodynamic properties, precise calculation is necessary for accurate performance estimations of internal combustion engines. Meeting these fundamental needs and providing combustion analysis of numerous fuel blends of various mixing ratios, this new model can be a recourse tool for researchers working on fuels, surrogates, emissions and internal combustion engine modelling. Simulations of any combustion process including existence of exhaust gas recirculation, supplementary firing, steam injection, argon dilution, water injection, fuel emulsification and reheat process in gas turbines can easily be conducted by integrating this validated model into thermodynamic cycle models.

Simulation of Steam Injection Process for Horizontal Well with Heavy Oil Recovery

ABSTRACTHorizontal well technology is widely used in the production of heavy oil. Steady-state model is used as main research method and assume constant wet steam parameters in wellbore, ignoring the impact of heat and mass transfers of steam from wellbore to the reservoir. Numerical calculation is used to analyze steam-water-oil three-phase on flow and heat transfer rule in reservoir and wellbore in startup phase. The influence rule on diffusion process of vapor and water hindered by oil stockpile in wellbore was analyzed, as well as vapor and water parameters change rule along the well. Result indicated that wet steam moving forward was hindered by oil stockpile in wellbore, which lead reservoir suction steam to be not uniform; dryness and temperature of steam gradually reduce, resulting in high temperature at the heel and low temperature at the toe of reservoir; reservoir suction steam effect was improved and reservoir heated range was expanded gradually with the increasing of steam injection volume and dryness; variation of reservoir porosity and permeability have a similar effect on reservoir suction steam, comparing with steam injection volume and dryness. When porosity and permeability were enlarged, reservoir suction steam effect and reservoir heated range would become better.

Pore level investigation of steam injection processes; visualization of oil entrapment and steam propagation

The objective of this work is to model the steam injection process and examine the displacement physics at the grain-level. The primary focus is to quantify the oil entrapment behind the swept zone and investigate the pore-level steam propagation and chamber growth. A digital two-dimensional micro-model is reconstructed and fed into a finite element VOF-based solver. The solver is developed by adding necessary source terms to the Navier Stokes equation. The phase change is simulated using the Lee phase change model assuming that mass is transferred in a constant pressure and a quasi-thermo-equilibrium state. For each phase in the multi-region model, the mass conservation, Navier-Stokes momentum, and energy equations under non-isothermal conditions are solved simultaneously. In post-processing results, steam chamber development, vapor condensation over the oil-steam interface, and oil viscosity reduction due to the heat diffusion are demonstrated properly. The simulated oil entrapment behind the swept zone as well as the temperature distribution throughout the medium are in good agreement with the experimental datasets.

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One of the main challenges in developing a process of continuous steam injection is to control the injection profile. Said profile is strongly affected by steam channeling to “thief zones” and the gravitational effect of override, both are characterized by preventing contact of the steam with reservoir zones containing considerable amounts of hydrocarbons thus decreasing the vertical sweep efficiency. These phenomena are favored by some features of the formation such as large thickness and reservoir heterogeneities and may affect the technical and economic feasibility of the project if they are not controlled and / or monitored properly.Several methodologies have been designed to address this problem. Among them are injecting surfactants for the formation of in situ foam, which seeks to reduce the mobility of steam; using thermal gels, for plugging high permeability channels; injection of solvents, used to enhance oil mobility; and water-alternating-steam injection (WASP) for scavenging of both upper and lower zone of the formation. This article collects relevant aspects of the mentioned methods, and a comparison is made in base of the number of applications, incremental production and implementation cost.Keywords: Steamflooding, In Situ Foams, Solvents, High Temperature Gels, Water Alternating Steam.

Use of Nickel Nanoparticles for Promoting Aquathermolysis Reaction During Cyclic Steam Stimulation

Summary Late cycles of cyclic steam stimulation (CSS) are characterized by a decreasing heavy-oil recovery and an increasing water cut. Nickel nanoparticles can be used to promote aquathermolysis reactions between water and heavy oil in steam-injection processes, thereby increasing the recovery factor (RF). In this paper, detailed investigations were performed to determine the optimal operational parameters and answers to the following questions: What is the optimal concentration of nickel nanoparticles for promoting aquathermolysis under high steam temperature? Can we improve oil recovery at lower steam temperatures with the presence of nickel nanoparticles? What effect does the penetration depth of nickel nanoparticles have on the final oil recovery? CSS experiments were conducted between temperatures of 150 and 220°C. Steam generated under these temperatures was injected into sandpacks saturated with Mexican heavy oil. Powder-form nickel nanoparticle was introduced into this process to boost the oil production. In an attempt to obtain the optimal concentration, different concentrations were tested. Next, oil sands without any nanoparticle additives were first added into the cylinder. Then, only one-third of the sandpack was mixed with nickel nanoparticles near the injection port. Experiments were executed to study the effects of temperature, nickel concentrations, and nanoparticle-penetration depth on the ultimate oil recovery and produced oil/water ratios after each cycle. Produced-oil quality and emulsion formation were evaluated with gas-chromatography (GC) analysis, viscosity measurements, saturates/asphaltenes/resins/aromatics (SARA) tests, and microscopic analysis of the effluents. Experimental results show that the best concentration of nickel nanoparticles, which gives the highest ultimate oil RF, is 0.20 wt% of initial oil in place (IOIP) under 220°C, whereas the nickel concentration of 0.05 wt% provides the highest RFs at the early stages. A lower temperature of 150°C provides a much-lower RF than 220°C, which is mainly because of a lower level of aquathermolysis reactions at 150°C. By analyzing the compositions of produced oil and gas samples with GC and SARA tests, we confirm that the major reaction mechanism during the aquathermolysis reaction is the breakage of the carbon/sulfur (C/S) bond; the nickel nanoparticles can act as catalyst for the aquathermolysis reaction; and the catalytic effect becomes less remarkable from cycle to cycle. One run of the experiment to test the effect of particle-penetration depth revealed that the nickel nanoparticles distributed near the injection port greatly contributed to the ultimate RF.

The influence of steam injection for Enhanced Oil Recovery (EOR) on the quality of crude oil

ABSTRACTCurrently, due to reduction of oil reservoirs and the increasing need for oil as the main source for world energy, the need for production of heavy oil reservoirs is inevitable. The main purpose of this study is to determine the effectiveness of some operational and reservoir parameters and their impact on thermal and productive efficiency of thermal process of steam injection and quality of crude oil. In order to model the process, Eclipse-300 simulator was employed. Detection of these parameters, in addition to determining the best production scenario, can lead to the use of this method with better economic conditions. Hence, the results obtained from this study show that the optimal values obtained for operational parameters of stream injection such as steam quality, steam injection pressure, injection rate and well completion injection depth. The simulation results show that the use of optimal values of steam injection parameters can enhance efficiency of steam injection method and can make this method considered as third EOR method in heavy oil reservoirs than previously known in the petroleum industry.

Cambios en la permeabilidad y porosidad de medios porosos no consolidados debido a cambios en el esfuerzo de confinamiento y la temperatura - Un estudio experimental

Los procesos de recobro térmico se constituyen en una técnica eficiente y comúnmente aceptada para la explotación de los yacimientos de crudo pesado. El aumento de la temperatura del medio poroso como resultado de la inyección de vapor en los procesos de recobro térmico, reduce en forma significativa la viscosidad del petróleo y hace posible el flujo del mismo hacia los pozos productores. En los últimos años, se han presentado avances tecnológicos que han permitido que tales operaciones estén monitoreadas y que la operación sea más rentable y segura, desde la perspectiva de aseguramiento de la integridad del sistema de flujo en superficie. El aseguramiento de la capacidad de flujo de la formación al igual que la integridad mecánica de la formación productora y las formaciones suprayacentes con los cambios en presión y temperatura promovidos por el proceso de inyección de vapor, es un tema de actual vigencia, dadas sus implicaciones económicas y medioambientales, en especial para yacimientos de crudo pesado a profundidades someras. Por lo tanto, procurar la comprensión correcta de lo que sucede en el yacimiento y las formaciones suprayacentes durante el recobro térmico se ha convertido en un tema de interés para reducir el impacto ambiental de estas operaciones y generar modelos que predicen la producción y el factor de recobro con precisión y fiabilidad. Evidencias experimentales plantean que la productividad y la capacidad de flujo de los pozos afectados por procesos de recobro térmico no sólo dependen del efecto de la temperatura sobre la viscosidad del petróleo pesado, sino que también involucran el efecto de la temperatura sobre las propiedades tanto petrofísicas como mecánicas del medio poroso. Por lo tanto, la comprensión del comportamiento geomecánico y petrofísico de las formaciones geológicas bajo diferentes escenarios de esfuerzos y temperatura es fundamental para modelar los diferentes procesos al interior del yacimiento durante el recobro térmico, y en particular los que determinan la productividad de los pozos y el factor de recobro del proceso. El artículo presenta los resultados de laboratorio acerca del comportamiento de la porosidad y la permeabilidad con la temperatura y el esfuerzo de confinamiento en un medio poroso no consolidado. La evaluación hace uso de núcleos reconstituidos a partir de muestras de formación no consolidadas saturadas con petróleo pesado. Para cada condición de esfuerzo de confinamiento, se realizó el registro del cambio con temperatura del volumen poroso, el volumen total y la permeabilidad de la muestra a diferentes etapas de calentamiento. Los resultados evidencian una dependencia significativa de la permeabilidad y porosidad con el esfuerzo de confinamiento al que se somete el medio poroso. A mayor esfuerzo efectivo de confinamiento, mayor es la reducción de la porosidad y permeabilidad al aumentar la temperatura; mientras que a bajo esfuerzo de confinamiento, se mantiene la tendencia para la permeabilidad pero no para la porosidad del medio poroso.

Vapor–Liquid Equilibrium of Bitumen–Ethane Mixtures for Three Athabasca Bitumen Samples

Steam–solvent coinjection processes have received more attention in the past decade due to the environmental impact of the pure steam injection process. Increasingly restrictive environmental regulations including carbon tax have served to push the industry to consider coinjection processes (steam + solvent) to reduce greenhouse gas emissions. Understanding the phase behavior of solvent/bitumen mixtures is critical for feasibility studies as well as the design and implementation of a successful coinjection process. This study presents the vapor–liquid equilibria for bitumen/ethane mixtures and their applications for bitumen recovery processes. Experiments were conducted for temperatures up to 190 °C and pressures up to 10 MPa to simulate the conditions of in situ steam processes. The results of our vapor–liquid equilibrium experiments include solubility, viscosity, and density measurements of the saturated liquid phase, k-values, and gas oil ratio. Increasing the temperature from 50 to 150 °C resulted in ...