Is there a cleaner and more efficient way to extract bitumen from Canada’s oil sands? Suncor Energy thinks the answer is ESEIEH, writes Tim Skelton
Suncor Energy and its partners are pioneering a new application of an old technology that could revolutionise how oil sands are processed. They are using radio frequency (RF) heating to soften and loosen the oil, offering the potential to replace current energy-intensive extraction methods.
Existing methods for extracting bitumen from oil sands in Alberta in Western Canada have been criticised by environmental groups for being too dirty. The simplest methods use open-cast extraction, removing the oil-laden sand wholesale from the ground and removing the hard bitumen at a remote location. But this requires the intensive use of heavy digging equipment and haulers on the surface, which has a damaging impact on the landscape. Moreover, only around 20% of the region’s resources can be recovered using this method, as the remainder lie too deep below the surface.
In situ extraction technology using steam-assisted gravity (SAG) drainage plants are often heralded as cleaner alternatives to open-cast mining and more importantly can be used to exploit deeper-lying resources. This method involves injecting hot steam into the ground, which softens the bitumen, loosening it sufficiently for it to be pumped out directly from the ground.
But while this does represent an improvement, as the surface area suffers from less scarring, there are other drawbacks. The process requires a lot of steam. This in turn creates large volumes of wastewater. Furthermore, the burning of the fuel required to transform fresh water into steam is highly energy-intensive, and since this fuel is usually natural gas, it yields more greenhouse gas (GHG) per barrel of oil produced than even traditional open-cast mining methods. The construction and maintenance of the onsite steam-generating plants often also involves clear cutting of forests.
These problems have led the industry to hunt for alternatives to conventional extraction methods that are cheaper, more effective and leave less of an environmental footprint. One promising solution could come from an ongoing project called Enhanced Solvent Extraction Incorporating Electromagnetic Heating, or ESEIEH (pronounced “easy”) for short. ESEIEH is currently being developed by partners Suncor, Devon, Nexen Energy and US communications company Harris, which pioneered the technology.
The partners say ESEIEH has the potential virtually to eliminate the need for water at in situ operations. Instead of steam, it uses patent-pending antenna technology developed by Harris. Radio waves heat and soften the oil sands electrically, in a manner not dissimilar to a giant underground microwave oven. A recyclable hydrocarbon solvent is then injected into the extraction zone to dilute and loosen the bitumen, with the minimum of energy requirements. It can then be retrieved via a horizontally drilled well, pumped to the surface and transported for further processing.
Harris first promoted its concept to the oil sands industry in 2009, but only now are the benefits becoming clearer to the sector. “This technology has been in use by Harris for a number of decades, but never before applied to the production of bitumen,” Mark Bohm, Suncor’s manager for strategic in situ technology, told NewsBase. “The combined expertise of Harris and the industry know-how of our partners allowed us to come up with the concept of radio frequency and solvent extraction for in situ reservoirs.”
The group developing the project began exploring the possibilities for using this RF heating technology in 2011, when the first tests were carried out at Harris’s home base in Florida. The initial physical testing of the technology then took place in 2012 in a mine face at Suncor’s Steepbank facility, north of Fort McMurray in northeast Alberta. “That stage of testing proved that the radio frequencies could heat a bitumen reservoir,” Bohm said. “The results from this phase were encouraging, indicating that RF could be used effectively to heat bitumen in situ.”
The early testing phase paved the way for a scaled-up ESEIEH pilot scheme – the first production test of the technology on actual subterranean oil sands deposits. This went into operation in mid-July this year, at Suncor’s Dover test site, also north of Fort McMurray. The test project – which is scheduled to run for around 24 months – is expected to cost in the region C$44 million (US$33.59 million). The funding came from the ESEIEH partners, as well as from the Canadian Climate Change and Emissions Management Corp. (CCEMC).
“For the current phase we are undertaking at the Dover site, we are testing within an in situ reservoir in a 100-metre well pair incorporating propane as a solvent into the process,” Bohm said. “The operations phase of the pilot has started, and we will be evaluating the results over the next two years.”
Bohm stressed that the pilot project was still in its very early stages, and as such there are no firm results yet. But he said the process as a whole had been encouraging. “The team has really come together successfully to start the field test and we’re excited to learn more about the potential of this technology,” he told NewsBase. “As this is a pilot, we’re continuing to refine the approach as to how to operate the subsurface and surface equipment. We’ll have more to report on our successes and challenges later.”
If the pilot proves to be a success, the group anticipates scaling things up in the next stage. “If this phase is successful, we will move onto a full-scale commercial demonstration plant that will incorporate multiple full-length well pairs,” Bohm said.
The hope is that the ESEIEH process will result in a reduction of up to 75% in energy requirements per unit volume of oil extracted. This, along with the complete elimination of the need for water in the in situ recovery process, is anticipated to improve environmental performance by significantly reducing GHG emissions, and also increase efficiency and reduce the capital expenditure required compared to traditional extraction processes. Moreover, the physical footprint of the well site can be reduced, as the need for a space-consuming steam generation plant is removed.
Should it prove commercially viable, ESEIEH radio frequency extraction technology could revolutionise oil sands extraction. It offers a cheaper and more efficient solution for oil companies, whilst also being considerably more environmentally friendly than existing methods. The industry will be watching the progress of the ESEIEH testing phase closely.