Experimental investigation on the separation performance of air‐adjustable underflow hydrocyclone

Abstract An adjustable structure of underflow diameters in real‐time is urgently needed to cope with the variability of the operating conditions of hydrocyclones. In this study, an air‐adjustable underflow structure was proposed. It is composed of a cylindrical metal casing with a rubber tube pressed in the middle. An air chamber was formed between the rubber tube and the metal casing. By regulating the pressure of the injected air in air chamber, the size of the fluid channel can be adjusted in real‐time. The separation performance, including solid yield, separation precision, and classification efficiency, of the hydrocyclone with the air‐adjustable underflow and the hydrocyclone with a conventional underflow was compared. The results indicate that the hydrocyclone with the air‐adjustable underflow not only enables adjustability during the separation process but also maintains comparable performance with traditional hydrocyclones in key metrics. Specifically, the underflow split ratio and solid yield of the air‐adjustable underflow exceed those of the conventional design. Moreover, under low feed pressure, the air‐adjustable underflow achieves superior separation precision and classification efficiency compared to the conventional underflow. However, under higher feed pressures, slight deformation of the rubber tube of the adjustable underflow port may occur, which would reduce its efficiency. These findings offer valuable guidance for the on‐site adjustment of hydrocyclones.