Shell Canada’s Quest project captures the world’s attention
Canada’s oil sands have become the cause of the moment for every celebrity activist looking to make a media splash and to shore up their credentials as good global citizens and saviours of the planet.
Former U.S. Vice-president Al Gore, Film Director James Cameron and most recently Singer-songwriter Neil Young have all taken turns denouncing oilsands extraction for allegedly destroying the boreal forests of northern Alberta, poisoning the lakes and rivers, and spewing tonnes of greenhouse gases into the atmosphere.
However, they routinely overlook the fact that oilsands producers utilize world-class technology, contribute billions of dollars annually to the Canadian economy and employ thousands of Canadians, including Aboriginals and many Maritimers who have stepped up to fill many employment opportunities.
Nor have they bothered to take note of Shell Canada’s $1.4-billion Quest carbon capture and storage (CCS) project, which is currently under construction at the company’s Scotford heavy oil upgrader, 50km northeast of Edmonton, which is scheduled to begin operating in 2015.
Quest will strip one million tonnes of CO2 annually from the emissions at Scotford, convert it from a gas to a liquid and move it by pipeline some 60km north where it will be injected into a basal cambrian sandstone formation two kilometres beneath the surface.
“It is a globally significant carbon capture and storage demonstration project,” says Chris Severson-Baker, managing director of the Pembina Institute, a Calgary-based energy and environment think tank.
“Quest won’t do much to reduce the overall amount of CO2 going into the atmosphere, but if we get to the point where the technology is proven and investors, regulators, other companies and the public see that this can be done safely. It could open a whole new approach to addressing climate change.”
Carbon capture and storage has been touted for over a quarter of a century as a method of reducing greenhouse gas emissions from a number of sources, including oil and gas production, coal-fired power plants, chemical and fertilizer plants and steel and cement plants. Government agencies in the U.S., Great Britain, Germany and Norway, as well as South Africa, China and India have either studied the concept or worked with utilities and energy companies to develop CCS facilities, and four pilot projects, are in various stages of development in Australia.
To date, though, none of these initiatives have led to the construction and commissioning of commercial-scale CCS facilities, which has allowed Canada to assume a leadership role.
In 2011, the Saskatchewan government approved a $1.35-billion CCS project at SaskPower’s Boundary Dam coal-fired power plant, just outside the city of Estevan in the southeast corner of the province. It is slated to begin operating this year and is described as the world’s first post-combustion, coal-fired CCS project.
It will strip one million tonnes of CO2 annually, which is equivalent to taking more than 250,000 cars off the road, from the emissions produced by one of the plant’s six generating units. The system will also capture sulphur dioxide (SO2 ), which will be converted to sulphuric acid for sale to industrial users, as well as fly ash, which can be used in ready-mix concrete and various other concrete products. Meantime, most of the CO2 will be transported by pipeline to nearby oilfields where it will be injected in order to boost production from aging wells.
Shell’s Quest facility appears certain to become the world’s first commercial-scale CCS facility in the oil and gas sector when it begins operating next year. It is being jointly funded by Shell, the Alberta government, which will contribute $745 million over 10 years, and Ottawa, which will kick in $120 million.
Tim Wiwchar, Shell’s Business Opportunity Manager in charge of engineering, construction and commissioning of the project, says that it was conceived and developed largely in response to public and political pressure on oilsands producers to reduce their greenhouse gas emissions.
Quest will strip CO2 from the diluted bitumen arriving by pipeline at Scotford from Shell’s Muskeg River and Jackpine mines. The dilbit, as it is known in the industry, goes first to a separation unit where heat and pressure are applied in order to release the diluents, which are captured and sent to another unit for further processing. The bitumen is moved to a vaccum tower and subjected to very high temperatures to separate as much light oil as possible, leaving behind a residue of heavy oil which, at room temperature, resembles asphalt or a hockey puck, says Wiwchar.
Meantime, in another part of the Scotford refinery called the hydrogen manufacturing unit, steam and methane gas are combined under extremely high tempertures. A solid metal catalyst consisting of cobalt and molybdenum is added to the mix to trigger a chemical reaction that yields pure hydrogen, which is then used to turn heavy oil into lighter crude. But CO2 is a byproduct and is currently allowed to go up a stack and into the atmosphere and the Scotford refinery emits enormous amounts of it–some three million tonnes annually.
Once the Quest facility is complete and fully commissioned, the CO2 and hydrogen will be piped to a capture vessel where a solution consisting of water and a proprietary chemical called amine is introduced. This solution absorbs the CO2 and is then sent to stripping tower where, under the right heat and pressure, the CO2 is released. From there it is moved to a compressor, which reduces the volume by a factor of four hundred and turns it from a gas to a liquid.
The liquid CO2 is then transported 60km north by pipeline to the injection wells and pumped into the basal cambrian sandstone formation that is saturated with saltwater that is millions of years old, say Wiwchar. The CO2 dissolves and becomes trapped.
Shell has been using amine technology for several decades to strip hydrogen sulfide and CO2 from natural gas. The only really new part of the whole process is the storage of CO2 underground and the development of methods to measure the amounts being pumped down and to monitor the formation to ensure that there is no upward migration of CO2-laden brine.
“The storage zone has enough capacity to go beyond 25 years at one million tonnes per year,” says Wiwchar. “We had to provide the government assurances that we are keeping track of the CO2 and making sure it stays underground.”
The Quest CCS facility will eliminate about 35 per cent of the three million or more tonnes of CO2 emitted annually at the Scotford upgrader. Shell’s Muskrat River and Jackpine mines also generate some three million tonnes of CO2 each year, largely from enormous excavators used to mine the bitumen and the huge trucks that haul it away.
Thus this carbon capture and storage project is only a first step, but it is an important one, says the Pembina Institute’s Severson-Baker. “There’s going to be a need for a process like this to capture CO2 from heavy industry,” he says. “We’ll be using fossil fuels for many, many years and without something like CCS it’s very difficult to see how we can reduce greenhouse gas emissions. That’s why our organization has been supportive.”
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