Steam injection is often not a good alternative for oil recovery fromshallow bitumen reservoirs. For instance, the thin caprock creates the dangerof steam breakthrough. For deeper reservoirs, the heat losses from injectionwells may be prohibitive. A technology that may be better suited is oilrecovery aided by low-frequency electrical heating of the reservoir. Thistechnology, well known for environmental remedial applications, has been fieldtried recently, yielding promising results. The process uses electricconductivity of connate water to propagate an alternating current betweenelectrodes, inducing the Joule heating of the reservoir. An associated problemis the appearance of hot spots around the electrodes that may be relieved bywater circulation. However, the water circulation may have a significant effecton the heating process because the electric conductivity of the circulatedwater depends on its salt content. To find out the influence of salt concentration on process efficiency, wehave studied the process of salt-water recirculation around an electrode usingnumerical simulation. The physical properties and operational data forAthabasca bitumen have been collected from the literature. The model built withComputer Modelling Group's STARS simulator and tested first with availableanalytical solutions has been validated, and the proper choice of theunderlying grid and numerical tuning parameters has been verified. The processwas also simulated at field scale for a common pattern of electrodes andproduction wells. The salt penetrated into the reservoir, far beyond the majorwater-circulation zone around the electrodes. This process increases theelectric conductivity in a large region between electrodes, which improves theheating of the reservoir. The single-electrode simulation studies usingdifferent tools yielded similar results for a simple problem. More-complex (andmore-realistic) field-scale simulations show that adding salt enhances the oilproduction. In practice, an upper concentration limit may be given by corrosionproblems at the electrodes. The reservoir simulation of bitumen recovery assisted by low-frequencyheating is a challenging multiphysics problem. The understanding of theinfluence of salt concentration on the circulated water provided by this workis an important key in process-design considerations.

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