Scientists of the Siberian Federal University (SFU) have proposed using domestic nanofibers to improve the quality of solutions used in drilling oil and gas wells in permafrost. The additive will improve drilling efficiency, reduce equipment wear and environmental damage from mining. The results are published in the Journal of Molecular Liquids. The research work was carried out within the framework of one of the priority activities of the SEC “Yenisey Siberia” – new industrial technologies.
The development of oil and gas fields in the Arctic and a number of adjacent regions is difficult due to difficult mining, geological and climatic conditions, experts noted. According to them, the effective development of the industry in this region requires new technological solutions.
Water-based drilling fluids used in the construction of most oil and gas wells are of little use in permafrost conditions, scientists reported: the irretrievable losses of the solution during drilling are quite large, and the borehole thaws from the water, which leads to its rapid destruction.
As experts explained, in the Arctic conditions, hydrocarbon-based solutions are much more effective, which, unlike water, allow avoiding excessive swelling of clay deposits that greatly complicate the drilling process, as well as some other problems.
SFU scientists proposed using aluminum oxide nanofibers to improve the properties of hydrocarbon-based drilling fluids. According to them, such an additive will reduce equipment wear and mortar losses, and will also help to pump drilled rock out of the well more efficiently.
“Drilling mud with the addition of nanofibers can ensure the stability of the borehole not only in permafrost, but also in shale formations, and also reduce the environmental impact by eliminating the use of standard toxic chemicals in drilling mud,” said Maxim Pryazhnikov, a researcher at the Laboratory of Physico–chemical Technologies for the development of hard-to-recover hydrocarbon reserves of SFU.
The proposed nanofibers are a unique crystalline material of a new generation with ultra-high mechanical strength and forming stable dispersions, the researchers said.
The test results showed that in the optimal concentration range, the nanofibers used not only significantly facilitate the pumping of the drilled rock, but also reduce the coefficient of friction and reduce solution losses by 2.5 times.
According to SFU scientists, they also comprehensively investigated the effect of aluminum oxide nanofibers on various properties of hydrocarbon-based drilling fluids.