New hybrid steam-solvent processes in heavy oil recovery

A look at new hybrid processes that augment SAGD and VAPEX to increase heavy oil recovery.

In SPE 101717-MS authored by T.N. Nasr and O.R. Ayodele of the Alberta Research Council and presented at the November 2006 Abu Dhabi International Petroleum Exhibition and Conference, ongoing research and analysis of two relatively new hybrid steam-solvent injection processes was discussed.

The paper looked at two primary processes: Expanding Solvent-SAGD (ES-SAGD) which hopes to improve and extend SAGD performance by solvent addition to steam and the Thermal Solvent Hybrid process focuses on combining solvent with a small amount of steam in a VAPEX™ (vapor extraction) process. This process offers the potential of higher rates than cold solvent VAPEX™ at less energy.

Early ES-SAGD lab results where promising in that not only was oil recovery over conventional SAGD increased but there were also improvements in oil-steam ratios with accelerated oil production thus reducing steam requirements and GHG emissions.

While these hybrid techniques are still under research and remain to be proven at scale in the field, they remain promising in expanding heavy oil production and worth investigating.

Jorge.