Development of Solvent and Steam-Solvent Heavy Oil Recovery Processes Through an Integrated Program of Simulation, Laboratory Testing and Field Trials

Abstract

ExxonMobil and its Canadian affiliate Imperial Oil Resources are pursuing an integrated research program targeted at developing the next generation of heavy oil recovery processes which utilize light hydrocarbon solvents in conjunction with steam or as an alternative to steam-only processes to mobilize the in-situ heavy oil. The key benefits of employing solvent are improved economics and increased recovery from resource that is impractical with steam-only processes, improved environmental performance, particularly reduced greenhouse gas emissions and reduced water use.A suite of field trials, pilots and commercial applications have been operating over the past several years at Imperial Oil's Cold Lake field in Alberta, Canada. These have included both solvent-assisted and solvent-only field trials. Collectively, the results of these trials show that solvent recovery processes for heavy oil are technically viable and have considerable commercial potential. This paper summarizes the dimensions of the integrated research program that have been key to delivering the successful results to date. Simulation, laboratory testing and physical modelling with a focus on scaling to the field have been employed extensively prior to field testing. Short-term, relatively low cost field trials have been utilized to calibrate models prior to more costly, longer term pilots with dedicated facilities. Extensive field characterization has been conducted prior to final site selection and pilot operation. Integrated operational and surveillance plans have been employed to ensure measurable and reliable field performance data is acquired that can be used to calibrate and validate simulation performance. Finally, learnings from this integrated research program can be more broadly applied to the commercialization of other EOR processes and the research and development processes leading up to the decision to execute a major pilot.

A Critical Review of Reservoir Simulation Applications in Key Thermal Recovery Processes: Lessons, Opportunities, and Challenges

“…Chang et al (2009) used simulations to demonstrate that an application of LASER in horizontal wells could further augment production performance . Boone et al in 2014 summarized that a successfully integrated research program could bring success from a concept to field application, including simulation studies, laboratory testing, physical modeling, low-cost field trials, and longer-term pilots . For heavy oil reservoirs initially operated by cold heavy oil production with sand (CHOPS), cyclic solvent stimulation (pure solvent injection and production) with hot water flooding was applied to further improve oil recovery .…”

“…In situ combustion has also been tested as a CSS follow-up process. Its pilots were performed in Morgan Field with a reservoir depth of 200 m and thickness of 10 m and Margarite Lake with a depth of 450 m and a thickness of 34 m . Marjerrison and Fassihi (1995) performed simulation studies to history match performance of Morgan Field and to understand a high oil production rate of 19 m 3 /D from an individual well and an extremely low injected air to oil ratio of less than 355 m 3 /m 3 .…”

Investigation of Horizontal Well for Cyclic Steam-Solvent Stimulation to Escalate Heavy Oil Production

“…Steam flooding, cyclic steam stimulation, and steam-assisted gravity drainage are three of the most widely used and commercially viable steam injection techniques. In recent years, the global utilization of these techniques has increased significantly (Boone et al, 2014).…”

“…It is a gamechanging technology that has the potential to open up access to new resources that would otherwise be inaccessible via thermal processes. It significantly cut GHG emissions and water use (Boone et al, 2014). A schematic illustration of the concept of the combination of horizontal CSS and solvent injection is illustrated in Figure 2.…”

“…Figure 2. Schematic of combination of CSS and solvent injection where a solvent is injected into a horizontal well (Boone et al, 2014).…”