Engineering news
Researchers are using PET scans, more commonly used in the health service, to better understand and improve the mechanisms behind CO2 storage and oil production.
Since November 2015, the reservoir physics community at the Department of Physics and Technology (IFT), University of Bergen, Norway, have coordinated the five-year long research project CO2 Foam EOR Field Pilots, led by Professor Arne Graue. The project is a part of the CLIMIT programme, supported by the Research Council of Norway.
"The main goal of this project is to understand the physics behind displacement and to develop a new technology for synchronous CO2 storage and a more effective oil production by using CO2 foam," Graue said.
In order to gather knowledge on CO2 injections for combined storage and oil production in the North Sea in the future, the researchers will attempt a step-by-step scaling up from the laboratory to small oil fields in the American states of Mississippi and Texas, where CO2 is commercially available and the necessary infrastructure already exists.
The researchers believe that PET scans could become an important tool to evaluate storage capacity and potential for extraction. By using PET and radioactive tracers, the researchers can show the flow of liquid or gas in the rock. Radioactive CO2 is pumped into rock samples from the reservoirs where the CO2 is to be stored.
"By testing different imaging techniques like MRI, CAT and PET, we found that a combination of PET and CAT is optimal for our purposes," said IFT associate professor Martin A. Fernø.
The use of CO2 foam is also being studied to achieve more effective oil production and CO2 storage. By mixing foam from soap and CO2, the gas flow will decrease, and the gas will spread more widely in the reservoir. The mechanisms behind the formation of foam and the reduction in gas flow, will be studied using the PET technique.
"The result of creating more CO2 foam, is increased CO2 storage, and increased oil production, by injecting CO2 into old reservoirs," said Fernø.
The CO2 Foam EOR Field Pilots project includes 11 universities and 10 oil companies from five countries.
The oil industry is contributing to the pilot study by providing an oil field, financial support and internal expertise.
“The coal industry in the USA also support the project, and contribute with man-made CO2 to the field tests in addition to financial support,” said Graue. "The support from the Research Council of Norway´s CLIMIT programme has been vital for the realisation of our research,” he added.