Ural Federal University: Scientists Have Improved the Oil Gas Purification Device

Scientists have developed a transonic nozzle model for vortex tubes, which are used in the oil and gas industry to purify associated petroleum gas. The new development will eliminate the need to use compressor stations at wells, which will significantly reduce both capital and operating costs. Detailed calculations and results of the study are presented in the International Journal of Heat and Mass Transfer.

“The main area of vortex tubing application is the oil and gas industry. For example, together with produced oil, associated petroleum gas, which consists of many fractions, rises to the surface. In the past, this gas was burned directly at the well, which significantly polluted the environment. Currently, vortex tubes are used in oil production to turn the associated gas into raw material for its subsequent transportation,” says Vladimir Alekhin, the co-author of the publication and head of the department of computer-aided design systems for construction projects at UrFU.

The researchers conducted engineering calculations, developed a semi-uniformal numerical model, and applied 3D modeling to improve the characteristics of the vortex pipe. The scientists concluded that the low efficiency of standard vortex tubes is related to their structure. The cooling effect in a vortex tube arises from the exchange of energy between two oppositely flowing streams of compressed gas, but the standard nozzle design does not allow gas to be accelerated in supersonic mode. This leads to loss of significant amount of initial energy of compressed gas. Scientists argue that the efficiency of the vortex tube can be improved by increasing the pressure of the compressed gas at the inlet and adding a new supersonic section to the vortex tube nozzle. They are now working to further improve it.

“The energy separation effect in vortex tubes is an unresolved fundamental problem. The physical mechanisms leading to temperature stratification in vortex tubes are not completely clear. We are now weighing possible options for continuing research on the new nozzle apparatus. We would like to achieve the application of vortex tubes for condensation of certain fractions from the gas stream. In addition, there are a number of potential applications of vortex tubes, such as condensation of water from humid air or cooling and heating of indoor air. In all cases, a significant increase in their energy efficiency is required,” explains Anatoly Khait, the co-author of the study, associate professor of the Ural Federal University Department of Hydraulics.

Scientists from Ural Federal University, the University of Genoa (Italy), and representatives of the design bureau ChKZ-YUGSON (Ekaterinburg) have been working on this development. This group has been working on the study and improvement of vortex tubes since 2013.