In Situ Upgrading Technology
Converts Bitumen to 100% transportable, no diluent needed
ISUT™ is not a conventional thermal recovery process. It entirely eliminates the energy and emissions-heavy step of surface upgrading required in SAGD recovery, by taking that upgrading step off the surface and putting it underground, in the reservoir itself, by coupling production and upgrading into a single step. ISUT™ is in-situ (in-the-reservoir) upgrading that converts low API, low mobility, extra heavy oils – such as oil sands bitumen (typically 8-10° API) – into lighter oil (22-25° API) similar to medium gravity crudes, while reducing greenhouse gas emissions by over 30%.
ISUT™ has a strong potential to replace thermal (steam) in-situ production processes that are prevalent in Canada’s oil sands, are expensive and have significant negative environmental impacts. The process may initially be deployed as enhanced oil recovery (EOR) at brownfield (existing) operations with minor surface facility improvements, re-using significant capital investments while improving recovery and NPV of the resource. Capital and operating costs would be significantly reduced compared to SAGD due to the process’s decreased requirement for steam and diluent addition, with a very modest investment in ISUT™ surface equipment. Production would be enhanced by +50% compared to SAGD.
The more modest surface facilities of ISUT™ when deployed as a SAGD EOR technology include the simple two-plate vacuum distillation unit (VDU) and the catalyst preparation zone (CatSKID™). Some of the pre-existing SAGD surface equipment could be downsized or removed; alternatively, it may be utilized for brownfield expansion of SAGD operations at the same site.
The VDU separates the oil into two fractions. The bottom VDU fraction is vacuum residue (VR) that is subsequently combined with hydrogen and monometallic nickel and molybdenum nanocatalyst particles by the CatSKID™ prior to reservoir injection. The field-pilot sized CatSKID™ is designed to prepare ultra-dispersed catalysts in a heavy oil fraction like vacuum residue at a rate between 70 and 140 bpd.
Once in the reservoir, the catalysts get attached to the sand forming a catalytic bed that with high temperature and the presence of hydrogen improves the quality of the oil and enhances the rate of recovery of the heavy oil.
The top VDU fraction is the upgraded, residue-less oil which, at 20-25º API gravity, is pipeline transportable without the up to 30% diluent addition utilized by in-situ oil sands producers. This elimination of diluent saves significant transportation costs and increases pipeline capacity, an ongoing concern for bitumen producers in a market with growing volumes of product.
VR has the highest heat capacity among bitumen hydrocarbon distillation fractions and carries significant amounts of heat to the reservoir from the distillation process, replacing approx. 44% of the required steam for SAGD. While some heat through natural gas combustion will be required to provide the heat for the distillation column and for hydrogen generation, compared to SAGD energy use, the emissions and energy savings are still significant, at 32% reduction in GHGs and 43% reduction in energy intensity, based on an achieved SAGD SOR of 3. VR is also the most viscous fraction of bitumen, which makes it more effective to disperse and transport catalyst to the reservoir.
The VR fraction is considered low value “bottom of the barrel” and presents challenges to upgraders and refineries necessitating hydrocracking or thermal cracking to realize monetary value – emissions-heavy surface processes that are greatly reduced or eliminated in ISUT™. This technology effectively uses VR as a heat and catalyst carrier, hence VR never makes its way to a refinery. Instead, VR is continually reinjected into the reservoir affording a long residence time for conversion by upgrading into lighter, high-value oil over a number of injection cycles. By recycling VR into the reservoir, a lower severity upgrading process can be utilized and “fresh” VR can be combined with converted VR to maintain the stability of the produced oil. This process offers overall emissions reductions and energy efficiency improvements over what would be required through upgrading the VR at the surface and not in the reservoir itself.
The top fraction produced by the VDU is a residue-less upgraded crude oil that is a mixture of naphtha, kerosene and other hydrocarbon distillates (“gas oils”) and is immediately fungible at North American refineries thereby reducing or eliminating the heavy oil discount associated with Western Canadian Select. This upgraded crude is similar in physical properties to light tight (shale) oil, although chemically quite dissimilar.