The upstream greenhouse-gas (GHG) emissions intensity of bitumen from the Canadian oil sands has fallen on average since 2009 and will continue doing so through 2030, says a study by IHS Markit.
During 2009-17, the study says, emissions from upstream operations per barrel of bitumen produced fell by 21%. A further 16-23% lowering of emissions intensity is possible over the next decade.
Upstream operations include bitumen extraction and initial processing.
Most of the 2009-17 decline came in mining operations through improvements at legacy mines and the use in newer mines of methods not requiring on-site upgraders, such as paraffinic froth treatment (PFT), the study says.
On a marketed-product basis, GHG emissions intensity of mining fell 26% during the period.
The study notes that the refining of diluted bitumen produced through PFT is more GHG-intensive than that of the synthetic crude oil (SCO) yielded by upgraders. On a full-lifecycle basis, however, GHG emissions of diluted bitumen generally remain below those of SCO.
IHS Markit expects a further 15-20% reduction in GHG emission intensity from mining during 2017-30.
SAGD reductions
For steam-assisted gravity drainage (SAGD), which will account for most future oil sands production growth, IHS Markit sees a reduction in GHG emissions intensity of 17-27% during 2017-30 from application of commercial and near-commercial technologies and efficiencies.
“SAGD is still a relatively new process and has yet to undergo any of the transformational changes that occurred in mining,” says IHS Markit Executive Director Kevin Birn, who heads the firm’s Oil Sands Dialogue. “The majority of emissions intensity reductions to date have come from incremental improvements and learning by doing. However, the analysis here shows that even a modest set of advancing individual improvements working together could result in more dramatic reductions.”
The study notes that two proposed thermal operations would inject solvent to lower steam requirements.
The 2017-30 projections would bring full-lifecycle GHG-emissions intensity of bitumen from oil sands to within 2-4% of the average crude oil refined in the US for SAGD and 5-7% for mining.
Projects vary greatly in GHG emissions intensity, the study points out, warning that a focus on averages can be misleading.
Upstream GHG emissions intensities of oil sands facilities in 2017 ranged from 39 kg of carbon dioxide-equivalent/bbl of bitumen to 127 kg/bbl.
Compared with the average crude oil refined in the US, those oil sands GHG intensities ranged from 1% below to 16% above on a full-lifecycle basis.