| 摘要 |
A process and system which integrates on-site heavy oil or bitumen upgrading and energy recovery for steam production with steam-assisted gravity drainage (SAGD) production of the heavy oil or bitumen. The heavy oil or bitumen produced by SAGD is flashed to remove the gas oil fraction, and the residue is solvent deasphalted to obtain deasphalted oil, which is mixed with the gas oil fraction to form a pumpable synthetic crude. The synthetic crude has an improvement of 4-5 degrees of API and lower in sulfur, nitrogen and metal compounds. The synthetic crude is not only more valuable than the heavy oil or bitumen, but also has substantial economic advantage of reducing the diluent requirement since it has lower viscosity than the heavy oil or bitumen. The asphaltenes, following an optional pelletizing and/or slurrying step, are used as a fuel for combustion in boilers near the steam injection wells for injection into the heavy oil or bitumen reservoir. This eliminates the need for natural gas or other fuel to produce steam at reservoir location and thus improves the economics of the heavy oil or bitumen production substantially. Alternatively, the asphaltenes are used as a feedstock for gasification to produce injection steam, synthesis gas. The CO2 could be used as additive with injection steam to enhance the performance of SAGD and the hydrogen could be exported to nearby processing facility. The invention upgrades the heavy oil or bitumen to a synthetic crude of improved value that can be pipelined with reduced amount of diluent, while at the same time using the asphaltene fraction of the residue for combustion to fulfill the energy requirements for generating injection steam for SAGD.
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