Siberian Federal University

The development of oil and gas fields in the Arctic and some adjacent regions is complicated by difficult mining, geological and climatic conditions, experts noted. They also say that 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 say. The irretrievable losses of the fluid during drilling are quite large, and the borehole thaws from the water, and that leads to its rapid destruction.

As experts explained, hydrocarbon-based fluids are much more effective in the Arctic conditions. Unlike water, those fluids allow avoiding excessive swelling of clay deposits that greatly complicate the drilling process, as well as some other problems.

Scientists of Siberian Federal University have proposed using aluminum oxide nanofibers to improve the properties of hydrocarbon-based drilling fluids. They say that such an additive will reduce equipment wear and fluid losses, and will also help to pump cuttings out of the well more efficiently.

"Nanoparticle additives can significantly change the functional properties of drilling fluids. Highly non-isometric particles, such as fibers or filaments, even in small quantities significantly increase the stability of colloidal fluids, thereby increasing the efficiency of drilling operations," said Maxim Pryazhnikov, researcher at the Laboratory of Physico-Chemical Technologies for the Development of Hard-to-recover Hydrocarbon Reserves of SibFU.

The proposed nanofibers are unique crystalline material of a new generation with ultra-high mechanical strength. It forms stable dispersions, the researchers said.

The test results showed that in the optimal concentration range, the nanofibers not only significantly facilitate the pumping of the drilling cuttings, but also reduce the coefficient of friction and reduce fluid losses by 2.5 times.

"Drilling fluid with the addition of nanofibers can ensure the stability of the well not only in permafrost, but also in shale formations, as well as reduce the environmental impact by eliminating the use of standard toxic chemicals in drilling fluid," noted Maxim Pryazhnikov.

According to the SibFU scientists, they also comprehensively studied the effect of aluminum oxide nanofibers on various properties of hydrocarbon-based drilling fluids.

The scientists used aluminum oxide nanofibers obtained by the co-authors of the work from the Federal Research Center Krasnoyarsk Research Center of the Siberian Branch of the Russian Academy of Sciences, using their own technology based on the oxidation of aluminum melt in a controlled gas environment.

The research is carried out within the framework of the grant of the Russian Scientific Foundation Development of new micro- and nanofluidic technologies for the tasks of the oil and gas industry.

SibFU is a participant of the Priority—2030 program of state support of universities of the Russian Federation.