Life Cycle Greenhouse Gas Emissions of Current Oil Sands Technologies: GHOST Model Development and Illustrative Application

Abstract

A life cycle-based model, GHOST (GreenHouse gas emissions of current Oil Sands Technologies), which quantifies emissions associated with production of diluted bitumen and synthetic crude oil (SCO) is developed. GHOST has the potential to analyze a large set of process configurations, is based on confidential oil sands project operating data, and reports ranges of resulting emissions, improvements over prior studies, which primarily included a limited set of indirect activities, utilized theoretical design data, and reported point estimates. GHOST is demonstrated through application to a major oil sands process, steam-assisted gravity drainage (SAGD). The variability in potential performance of SAGD technologies results in wide ranges of "well-to-refinery entrance gate" emissions (comprising direct and indirect emissions): 18-41 g CO(2)eq/MJ SCO, 9-18 g CO(2)eq/MJ dilbit, and 13-24 g CO(2)eq/MJ synbit. The primary contributor to SAGD's emissions is the combustion of natural gas to produce process steam, making a project's steam-to-oil ratio the most critical parameter in determining GHG performance. The demonstration (a) illustrates that a broad range of technology options, operating conditions, and resulting emissions exist among current oil sands operations, even when considering a single extraction technology, and (b) provides guidance about the feasibility of lowering SAGD project emissions.

Energy consumption and greenhouse gas emissions in the recovery and extraction of crude bitumen from Canada’s oil sands

“…The waste heat energy in the exhaust is recovered in the heat recovery steam generator (HRSG). 55% of the heat in the exhaust is recovered in HRSG [44]. The exhaust energy may or may not be sufficient to heat process water.…”

“…Conditions at which the steam is generated in oil sands are project specific and range from 3.5 to 8.9 MPa with steam quality varying from 65% to 98%. The default steam condition used in a SAGD operation is 8 MPa [26] with a steam quality of 80% [44]. Further the variation of these factors is studied in sensitivity analysis in Section 3.3.2.…”

“…The natural gas consumed in the process also depends on the amount of coproduced gas. Produced gas in SAGD ranges from 1 to 89 m 3 /m 3 of bitumen [44,49,50]. Most of the produced gas is conserved and utilized so as to reduce the natural gas demand of the plant while a portion of it is flared.…”

Energy supplies and future engines for land, sea, and air

“…Complementary technology reviews, not all of them critical, are available for: (1) engines and turbines (Haglind, 2008a;Haglind, 2008b;Haglind, 2008c;Hausberger et al, 2012;Lloyd and Cackette, 2001;NRC, 2010a;NRC, 2011a;Sahoo et al, 2009); (2) biofuels production and use (Andrade et al, 2011;Balat, 2009;Balat and Balat, 2009;Carriquiry et al, 2011;Cheng and Timilsina, 2011;Deng et al, 2008;Hammerschlag, 2006;Hoekman, 2009;Hoekman and Robbins, 2012;Kralova and Sjoblom, 2010;Lin et al, 2011;Ma and Hanna, 1999;Mohan et al, 2006;NRC, 2011b;Pitz and Mueller, 2011;Sahoo et al, 2009;Shahid and Jamal, 2011;Sparks and Ortmann, 2011;Stamenkovic et al, 2011;Wang et al, 2009;Williams et al, 2009); (3) petroleum extraction and refining, including the oil sands (Alvarado and Manrique, 2010;Charpentier et al, 2009;Charpentier et al, 2011;Chhetri and Islam, 2008;Chung et al, 2012;Finan and Kadak, 2010;Gray et al, 2009); (4) coal extraction, use, and environmental consequences (Hook and Aleklett, 2010;Lighty et al, 2000;…”

Energy, Water, Cost, and Greenhouse Gas Implications of Steam-Assisted Gravity Drainage Surface Facility Technologies

“…Although the recent increase in global crude oil production has led to decreased oil prices and has challenged the Canadian crude oil industry, total oil sands bitumen production continues to grow albeit at a lower rate (CAPP 2015). The energy intensity of the oil sands extraction process has raised concerns over the associated environmental impacts, including greenhouse gas (GHG) emissions which tend to be higher when compared to conventional oil production (Charpentier et al 2011). As such, oil sands operators are seeking new technologies and improving current techniques to reduce these environmental impacts.…”