Oil sands in situ gasification recovery process design

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The volume of heavy oil and bitumen in Alberta, Canada is estimated to be about 1.7 trillion barrels. This oil has in situ viscosities typically in the hundreds of thousands to millions of centipoise and its extraction is energy intensive with large greenhouse gas emissions and water consumption. After extraction, most of the produced heavy oil and bitumen in Alberta is surface upgraded to synthetic crude oil which in turn can be converted to fuel, lubricant, and petrochemical products in standard refineries. To upgrade bitumen requires hydrogen. In current practice, much of this hydrogen is generated from steam reforming of methane together with the water-gas shift reaction. This means that heavy oil and bitumen upgrading, as is currently done, requires huge amounts of natural gas to generate hydrogen. The potential for in situ generation of hydrogen by gasification of bitumen reservoirs offers an attractive energy recovery alternative to oil sands recovery + upgrading which can also have both economic and environmental benefits. For example, hydrogen generated from bitumen gasification can also be used for in situ upgrading as well as feedstock for ammonia and other chemicals. The water-gas shift reaction also generates carbon dioxide which could be potentially sequestered in formation water and as solid mineral in an in situ gasification process so that emissions to the atmosphere are reduced over surface upgraders. In situ gasification technology provides a potentially clean method to produce fuel and feedstock material (hydrogen, methane) from bitumen, a relatively "dirty" fuel in addition to a more energy efficient way to extract oil (potentially upgraded oil product resulting from elevated temperatures). In the context of a carbon-neutral society, bitumen conversion to hydrogen is highly desirable since as an energy vector, it contains more energy per unit mass than any other combustible fuel. The key goal of this research program is the development of operating strategies and well placement to optimize the recovery of energy and feedstock chemicals (H2, CH4), thermal efficiency, and emissions intensity of an in situ oil sands gasification process as an alternative to current steam-based bitumen recovery and upgrading processes.