Experimental and theoretical study of separation performance of rotating impeller module with static cascade for grease particles

Abstract

Reducing grease particles of cooking oil fumes (COFs) emissions are essential for minimizing personal exposure risk and environmental impacts. Separation devices, such as baffle filter and rotating disk, are widely used as the primary stage to control grease particles emission, but these devices may be poorly designed and low separation efficiency, especially for fine particles. A novel rotating impeller module with static cascade (RIM-SC) is proposed. The effects of the operation parameters on the separation performance of the RIM-SC are experimentally investigated. Results indicate that the rotating impeller module (RIM) with static cascade B exhibits 40.8% separation efficiency (or removal rate) for PM2.5 at the exhaust airflow rate of 0.140 m3/s and the impeller input power of 125.5 W, which is significantly higher than the RIM with static cascade A. The RIM-SC also exhibits 100% separation efficiency of grease particles larger than 5 μm at the impeller input power range of 67.8–127.1 W and the exhaust airflow rate range of 0.140–0.185 m3/s. Additionally, a theoretical model of grade efficiency is established by geometric factors and escape coefficients. The validation results indicate that the satisfactory prediction accuracy can be obtained when the escape coefficients are 0.7–0.9 and 0.1–0.3.