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Abstract Use of chemicals as an additive during steam-based bitumen recovery processes has been an active topic for research and development in the last four decades. In this study, thermo-physical properties of mixtures of bitumen with a newly developed chemical are reported. This new chemical technology (i.e. IPC as referred in this paper) is a proprietary mixture of surfactants that has been used in several techniques associated with surface extraction as well as in-situ recovery of heavy oil and bitumen. This formulation of solvents and surfactants is reusable, low foaming, non-flammable, not acutely toxic and non-carcinogenic. A series of tests were conducted to measure density and viscosity of a bitumen, IPC, and different mixtures of bitumen-IPC at several pressure, temperature and chemical composition conditions. It was observed that solubility of IPC in bitumen was small, and its effects on the oil phase viscosity and density could not be separated from its effects on bulk properties caused by dispersed emulsified droplets of IPC. The impact of IPC on viscosity of mixture was more pronounced than its effect on mixture density. A very complex emulsion was formed upon contact of IPC with bitumen. The results of these tests will be useful in designing a steam-based bitumen recovery process with IPC as the chemical additive. Details of thermal stability analysis of IPC are also presented. Highlights • The effects of IPC formulation on density and viscosity of bitumen-IPC mixtures were studied. • Physical properties and thermal stability of IPC formulation was studied. • IPC formulation had no significant impact on mixture density up to 100 °C. • IPC formulation decreased the mixture viscosity at 100 °C and above. • Complex emulsions were formed upon low temperature mixing of IPC and bitumen. [ABSTRACT FROM AUTHOR]

Chemical-assisted waterflooding is injection of specialty chemical(s) along with water to enhance the productivity through a series of mechanisms. There are several mechanisms responsible for increased ultimate recovery of such a process compared to the traditional waterflooding process including in-situ emulsification of oil, conformance control and treatment of adverse mobility ratio, reduction of Interfacial Tension (IFT) between the in-situ oil and the injecting phase, and wettability modification to facilitate recovery of oil by enhanced relative permeability values. Although chemical-assisted waterflooding has been applied since the early 20th century, it has not been until recently that applicability of this process has been tested for recovery of heavy oil using preliminary macro-scale as well as pore-scale studies. A new chemical technology (i.e. IPC Technology as referred in this paper) has been developed. A proprietary mixture of surfactants is used in several techniques associated with surface extraction as well as in-situ recovery of heavy oil and bitumen. This formulation of solvents and surfactants is reusable, low foaming, non-flammable, not acutely toxic and non-carcinogenic. A systematic study, based on a series of coreflood tests, was designed and conducted to assess efficacy of IPC in the ultimate recovery of different types of oils by use of IPC-assisted waterflooding. Effects of IPC on IFT between oil and IPC solutions at different brine salinities/hardnesses and IPC concentrations were determined. Compatibility of IPC with different brine hardnesses and salinities was determined. IPC technology was particularly effective in recovering heavy oil. The performance of IPC as an additive during waterflood at elevated temperature for recovery of heavy oil was also investigated. For this particular purpose, thermal stability tests were conducted to determine the threshold temperature below which the formulation is thermally stable. When production performance of IPC-assisted waterflood was compared with alkali flooding and a commercial surfactant, IPC gave superior ultimate recovery. [ABSTRACT FROM AUTHOR]

Water-based drilling muds, a more environment-friendly candidate than oil-based drilling muds, are wildly used for drilling oil and gas wells. When water-based drilling mud is used for drilling formations with shale containing active clay constituents, it is challenging to preserve stability of the borehole due to clay swelling unless proper inhibition mechanisms are foreseen. In the current study, the feasibility of using Korean red Ginseng root extract was assessed as a clay swelling inhibitor. This root extract is rich in non-ionic surfactants such as Ginsenosides Rg3, Rg5, and RK1, and is referred to as "biosurfactant" throughout this manuscript. After preparation of mud systems containing problematic clay particles, the clay-swelling inhibition performance of the biosurfactant was systematically investigated through a series of tests, including mud formation, filtration, immersion, sedimentation assisted with optical microscopy, wettability by sessile drop technique, use of thermal gravimetric analysis (TGA), scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR), and shale cuttings recovery. The clay-swelling inhibition performance of the biosurfactant was then compared against two clay swelling inhibitors namely CTAB (Cetrimonium bromide, a known cationic surfactant) and potassium chloride. There are some properties associated with the mud systems prepared with biosurfactant solution which makes this product unique. These properties include: remarkable loading capacity of sodium montmorillonite (Mt) which in turn resulted in low rheological profile, poor fluid loss control, creation of stable Mt pellets, creation of larger size and aggregated Mt particles with less hydrophilicity, creation of fully unstable dispersed Mt particles that resulted in good sedimentation over time, less mass loss, and higher shale cuttings recovery, all compared to the baseline fluid made without the presence of biosurfactant. The results of this study indicate that the biosurfactant provides excellent clay swelling inhibition properties, comparable to known inhibitors. The biosurfactant's compatibility with other drilling mud components was also checked, and it was found that the fluid properties are independent of the biosurfactant. The wettability and FTIR analyses were also performed to investigate the mechanisms involved in clay swelling inhibition of the biosurfactant, which are believed to be as a result of coating the clay active surfaces with a hydrophobic layer, hence repelling the water phase. This hydrophobic layer is probably formed by interactions of the hydrophilic group of the Ginsenosides and the oxygen atoms available on the Mt surfaces, when the hydrophobic tail is oriented toward the aqueous phase. Image 1 • The feasibility of using a biosurfactant was assessed as a clay swelling inhibitor. • The biosurfactant exhibited an acceptable performance. • Wettability alteration is the more probable inhibition mechanism. • The biosurfactant was compatible with the drilling fluid componnts. • The biosurfactant is biodegradable, environmentally friendly, and relatively inexpensive. [ABSTRACT FROM AUTHOR]

Wellbore instability is one of the most critical challenges that continuously appear in drilling and production operations. Borehole breakout, as the enlargement and elongation of a borehole in a preferential direction, is an important phenomenon which should be addressed when stability of the wellbore is analyzed. Breakout pressure is an important parameter in wellbore stability analysis. In this paper, a geomechanical model was constructed using several petrophysical, field and lab data for one formation of interest to evaluate in-situ and induced stresses. Three shear failure criteria, namely Mohr-Coulomb, Mogi-Coulomb and Hoek-Brown were used to predict the breakout pressure profile and the outcomes were validated with 4-arm caliper log data of the well. The effect of azimuth and inclination of the deviated wells on the breakout pressure was investigated using stress transformation equations. It was found that the Hoek-Brown failure criterion with optimized constants resulted in the best prediction of the breakout pressure for this particular case under study. As for the deviated wells, inclination had an increasing effect on the breakout pressure whereas azimuth relative to the maximum horizontal stress could counteract it. [ABSTRACT FROM AUTHOR]