Mitigating greenhouse gas intensity through new generation techniques during heavy oil recovery

Heavy-oil is and will be an essential part of energy supply. The most common and practical way of producing any type of heavy-oil is steam injection; although this technique is both effectively and efficiently applied worldwide, there are many environmental and ecological concerns limiting the application. One of the most critical drawbacks of this proven method is the generation of greenhouse gases (GHG), which happens when the process obtains the remarkable amounts of steam needed. The focus of this paper is to discuss the eco-friendly methodologies to minimize GHG emissions (oil or natural gas consumption to generate steam) while sustaining the recovery at a comparable level of the currently available conventional in-situ heavy-oil and bitumen recovery techniques. New generation in situ techniques for heavy oil recovery including chemically assisted waterflooding or gas injection (non thermal), steam-based applications with additives (nano-based smart materials, surface-active agents, solvents), along with non-steam (solvent and electromagnetic heating) are outlined and a comparative analysis in terms of efficiency improvement while mitigating GHG emission is provided in this review paper. Comprehensive chemical lists for their potential use in each type of application are also provided. It is shown that a reduction of 20%-100% energy (oil or natural gas consumption) can be expected using the new generation in-situ recovery techniques for heavy-oil. (c) 2020 Elsevier Ltd. All rights reserved.