Laboratory Investigation of an Innovative Solvent Based Enhanced Recovery and In Situ Upgrading Technique

Abstract

As part of a three-year research project, a solvent based process for downhole upgrading as well as for concurrent enhanced oil recovery of the bituminous heavy oil from an Argentina reservoir was evaluated in the laboratory using physical models. Potential solvents were sourced from a gas plant located close to the target reservoir. To evaluate feasibility, first a specially designed dynamic asphaltene apparatus was used to screen readily available solvents and their mixtures. Solvent/oil miscibility and on-set of asphaltene deposition were determined by analyses of light transmitted through a micro-visual cell containing a flowing stream of oil/solvent mixtures. The optimized solvent composition thus identified was then used in Vapex experiment in a physical model packed with crushed reservoir rock.It was seen that the chosen solvent mixture (containing carbon dioxide and gas condensate) was effective in upgrading the produced oil under test conditions (high permeability). Asphaltene and heavy metal content of the upgraded (produced) oil were reduced to less than 20% of the original values, while oil recovery in excess of 75% of OOIP was achieved in the physical model. Oil sweep in the model, especially within the solvent swept zone was exceptionally efficient with a remaining oil saturation of less than 5%. At the same time, oil saturation of the least swept region was reduced from 85% to 45%. Deposition of asphaltenes in the porous medium did not seen to materially affect oil production

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

“…These techniques include thermal processes, such as steam assisted gravity drainage (SAGD) [4,5], cyclic steam stimulation (CSS) [6][7][8][9], steam flooding (SF) [10,11], in-situ combustion (ISC) [12,13] and cold techniques using diluents, among others. The latter (i.e., cold processes) are employed for improving the crude oil mobility by dilution or destabilization of large amount of crude oil components in the reservoir by injecting solvents for viscosity reduction [14,15]. On the other hand, the thermal enhanced oil recovery techniques for heavy oil upgrading include aquathermolysis [16][17][18], pyrolysis-also called thermal cracking or thermolysis [19][20][21][22]-combustion processes [23,24] and low-temperature oxidation [25,26].…”

Kinetics and mechanisms of the catalytic thermal cracking of asphaltenes adsorbed on supported nanoparticles

“…These techniques include thermal processes, such as in situ combustion and steam-assisted gravity drainage (SAGD) (Cavallaro et al 2008;Moore et al 1999;Greaves et al 2001;Kumar et al 2011;Kapadia et al 2010;Speight 1970;Jiang et al 2005;Fan et al 2004;Maity et al 2010), and cold techniques, such as treatments using diluents like natural gas condensate (Luo et al 2007a, b;James et al 2008;Castro et al 2011;Cavallaro et al 2005). The latter (i.e., cold process) is used to improve the crude oil by dilution or destabilization, and deposition of the asphaltene components in the reservoir by injecting solvents that have a direct impact on viscosity reduction (Luo et al 2007b;Cavallaro et al 2005).…”

“…These techniques include thermal processes, such as in situ combustion and steam-assisted gravity drainage (SAGD) (Cavallaro et al 2008;Moore et al 1999;Greaves et al 2001;Kumar et al 2011;Kapadia et al 2010;Speight 1970;Jiang et al 2005;Fan et al 2004;Maity et al 2010), and cold techniques, such as treatments using diluents like natural gas condensate (Luo et al 2007a, b;James et al 2008;Castro et al 2011;Cavallaro et al 2005). The latter (i.e., cold process) is used to improve the crude oil by dilution or destabilization, and deposition of the asphaltene components in the reservoir by injecting solvents that have a direct impact on viscosity reduction (Luo et al 2007b;Cavallaro et al 2005). The more frequently employed thermal techniques for heavy oil upgrading address breaking the heavier compounds of oil using combustion processes (Moore et al 1999;Cavallaro et al 2008), low-temperature oxidation (Xu et al 2000;Wichert et al 1995), aquathermolysis (Jiang et al 2005;Fan et al 2004;Maity et al 2010), and pyrolysis, also called thermal cracking or thermolysis (Speight 1970;Kumar et al 2011;Monin and Audibert 1988;Nassar et al 2013a).…”

Solvent Injection Strategy for Low-Temperature Production from Fractured Viscous Oil Reservoirs

“…It is the balance between these two effects that determines the net effect of asphaltene precipitation in oil production rate. It has been shown that the viscosity reduction dominates in the high-permeability packs commonly used in experimental models. − However, at more realistic permeabilities comparable to field values, the permeability impairment caused by deposition negates the benefits from reduced viscosity. , …”