Non-thermal oilsands tech touted as ‘game changer’
ExxonMobil process would eliminate tailings ponds, reduce GHG emissions
By Dan Healing, Calgary Herald
January 15, 2014
A new cold in situ technology called SHORE may have advantages over steam-assisted gravity drainage used at Cenovus Energy’s Foster Creek plant shown here.Photograph by: Photo courtesy Cenovus Energy
CALGARY — A new oilsands recovery technology envisions injecting cold water to mobilize whole sections of an underground formation — sand and bitumen alike — so it can be pushed to a well and sucked up to the surface.
Once there, the heavy oil would be separated using mining techniques and the cleaned sand reinjected into the formation to maintain pressure and continue to push the sand/bitumen/water slurry into a central producer well.
The process dubbed SHORE is touted as a potential “game changer” in a recent report into emerging technology trends in the oilsands by Calgary investment bank Peters & Co.
“The process is potentially capable of being applied in thinner and more geologically complex reservoirs that cannot be economically exploited by existing thermal processes,” Peters’ analysis reads.
“This could provide an option for development of shallow-to-intermediate depth bitumen resources.”
The report goes on to caution it will take “substantial time and capital” to prove commerciality and that it can be done safely and with acceptable levels of water use.
The technology is one of dozens being monitored by the energy technology branch of Alberta Innovates to assess and share with industry.
Project specialist Bruce Duong said Wednesday the ideas come from big and small players but all aim to improve economics and reduce adverse environmental affects of oilsands development.
“This technology is a bit unique,” he said of SHORE. “Most of the in situ technologies are dealing with solvent additions to a steam process ... and then there are some ideas around pure solvents to remove steam completely.
“The big driver here is moving toward improving resource recovery and reducing GHG emissions. There really have to be a wide array of different technologies to tackle different problems in different reservoirs.”
SHORE has been developed by American oil giant ExxonMobil Corp. and Calgary-based Imperial Oil Ltd. (70 per cent owned by ExxonMobil). The two share ownership of the Kearl oilsands mine which began production last year and Imperial is one of the largest producers of heavy oil in the Cold Lake region.
SHORE stands for Slurrified Heavy oil Reservoir Extraction and is described in a paper presented at the Society of Petroleum Engineers conference held in Calgary last year.
There, researchers said it has many potential advantages over thermal in situ techniques such as steam-assisted gravity drainage, or SAGD, where steam created by burning natural gas is injected through a horizontal well to melt the bitumen and allow it to drip into a parallel well to be produced.
“We have found that the process is likely to operate with significantly smaller CO2 footprint than thermal recovery processes, with complete disposal of tailings back to the subsurface and has the potential for zero fresh water use,” the paper notes.
“Recovery factors are likely to be in excess of 50 per cent with bitumen production rates per well in the range of 1,000 to 2,000 barrels per day.”
It says lab experiments suggest SHORE would work in formations with “mudstones,” solid objects that are the bane of thermal in situ operations because they block steam and solvent penetration. It adds the process could work in formations as narrow as five metres, too tight for SAGD.
“The technology is still in the early stages of development, but the laboratory and numerical modeling has demonstrated promising technical potential of the process at a field scale,” said Pius Rolheiser, a spokesman for Imperial Oil Ltd.
“Our intent is to test this in the field at the appropriate time, but we have no specific plans at this point.”
The research paper suggests groupings of five to seven vertical wells, with the injector wells surrounding a central recovery well.
Keeping the formation pressurized by reinjecting slurry is key to achieving a good rate of recovery because it prevents the formation from collapsing as the sand and bitumen is removed, the paper says.
dhealing@calgaryherald.com
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