Sequestration success

The US Department of Energy funded “Weyburn Project” has successfully sequestered five million tons of CO2 into the Weyburn Oilfield in Saskatchewan, Canada, while doubling the field’s oil recovery rate.

If the methodology used in the Weyburn Project was successfully applied on a worldwide scale, one-third to one-half of CO2 emissions could be eliminated in the next 100 years and billions of barrels of oil could be recovered.

“The success of the Weyburn Project could have incredible implications for reducing CO2 emissions and increasing America’s oil production. Just by applying this technique to the oil fields of Western Canada we would see billions of additional barrels of oil and a reduction in CO2 emissions equivalent to pulling more than 200 million cars off the road for a year,” said US Secretary of Energy Samuel Bodman.

In the first phase of the research project, co-funded by the Department of Energy, carbon dioxide was injected into the Weyburn Oilfield in Saskatchewan, Canada. The CO2 increased the underground pressure of the field to bring more oil to the surface. The project increased the field’s oil production by an additional 10,000 barrels per day and demonstrated the technical and economic feasibility of permanent carbon sequestration, the capture and permanent storage of carbon dioxide in geologic formations.

To compare, primary oil recovery, which uses natural underground pressure to bring oil to the surface, typically produces only 10 percent of an oilfield’s reserves. In secondary efforts, operators flood the field with water to force the oil into the wellbore and increase recovery to 20 percent to 40 percent.

Enhanced oil recovery (EOR), the technique used in the project, has the potential to increase an oil field’s ultimate oil recovery up to 60 percent and extend the oilfield’s life by decades. Scientists project that, by using knowledge gained from the Weyburn Project, the Weyburn Oilfield will remain viable for another 20 years, produce an additional 130 million barrels of oil, and sequester as much as 30 million tons of carbon dioxide.

The CO2 used in the project is piped from the Great Plains Synfuels Plant near Beulah, N.D., and is a byproduct of the plant’s coal gasification process. Before the Weyburn Project, much of the CO2 used in similar US EOR projects has been taken at considerable expense from naturally occurring reservoirs. Using an industrial source of CO2 sequesters this emission that would normally be vented into the atmosphere.

Now the Weyburn Project will move into Phase II where researchers will compile a best practices manual to serve as a world-class industrial reference in the design and implementation of CO2 sequestration in conjunction with enhanced oil recovery projects. They will also expand their efforts to the neighbouring Midale Unit, develop more rigorous risk-assessment modelling techniques, improve injection efficiencies, and monitor CO2 flooding and storage with a variety of methods, including seismic wave technologies and geochemical surveys.

The Weyburn CO2 Storage and Monitoring Project is a multinational effort led by Canada’s Petroleum Technology Research Centre in Regina, Saskatchewan, and cosponsored by the oilfield operator, EnCana Corporation of Calgary, Alberta. The project receives funding from the US Department of Energy, as well as industry and government organisations in Canada, Japan, and the European Commission.