Dual-Injection Airlift Pumps: An Enhanced Performance

Abstract

The airlift pump is a device for raising liquids or mixtures of liquids and solids through a vertical pipe, which partially submerged in the liquid, by using compressed air introduced at the lower end of the pipe. Airlift pumps are finding increasing use where reliability and low maintenance are required, and when compressed air or gas are readily available as an energy source for water and oil pumping applications. In comparison with other conventional pumps, the particular merit of the airlift pump is the mechanical simplicity. However, the main disadvantage of these pumps is their low efficiency especially at low liquid submergence ratio. In the present study, a dual injector is designed in order to increase the pump efficiency. The new injector is manufactured and tested for different water submergence ratios. The efficiency of the new design is found to be at least 30% higher than that of a conventional design. A proposed model for the analysis of the pump performance is presented and validated using the obtained experimental data. The model prediction of the pump performance is found to be in the range of ±15% of the obtained experimental data.

Keywords:

• airlift pumps
• annular injection
• dual-injection
• multi-injection
• two-phase flow

Acknowledgments

The authors would like to thank Hossam Al-Ghofaily and Rakan Al-Ajmi for taking the measurements and Romeo Agua for manufacturing the injector. The funding support of the Deanship of Scientific Research (DSR) at King Fahd University of Petroleum & Minerals (KFUPM) under Project No. IN111023 is gratefully acknowledged.