%A Anton ALVAREZ-MAJMUTOV,Jinwen CHEN %T Analyzing the energy intensity and greenhouse gas emission of Canadian oil sands crude upgrading through process modeling and simulation %0 Journal Article %D 2014 %J Front. Chem. Sci. Eng. %J Frontiers of Chemical Science and Engineering %@ 2095-0179 %R 10.1007/s11705-014-1424-z %P 212-218 %V 8 %N 2 %U {https://journal.hep.com.cn/fcse/EN/10.1007/s11705-014-1424-z %8 2014-05-22 %X

This paper presents an evaluation of the energy intensity and related greenhouse gas/CO2 emissions of integrated oil sands crude upgrading processes. Two major oil sands crude upgrading schemes currently used in Canadian oil sands operations were investigated: coking-based and hydroconversion-based. The analysis, which was based on a robust process model of the entire process, was constructed in Aspen HYSYS and calibrated with representative data. Simulations were conducted for the two upgrading schemes in order to generate a detailed inventory of the required energy and utility inputs: process fuel, steam, hydrogen and power. It was concluded that while hydroconversion-based scheme yields considerably higher amount of synthetic crude oil (SCO) than the coker-based scheme (94 wt-% vs. 76 wt-%), it consumes more energy and is therefore more CO2-intensive (413.2 kg CO2/m3SCO vs. 216.4 kg CO2/m3SCO). This substantial difference results from the large amount of hydrogen consumed in the ebullated-bed hydroconverter in the hydroconversion-based scheme, as hydrogen production through conventional methane steam reforming is highly energy-intensive and therefore the major source of CO2 emission. Further simulations indicated that optimization of hydroconverter operating variables had only a minor effect on the overall CO2 emission due to the complex trade-off effect between energy inputs.