Entrainment characteristics of fine particles under high speed airflow

¹ School of energy and environmental engineering, University of Science and Technology Beijing, Beijing 100083, China
² Beijing Key Laboratory of Energy Saving and Emission Reduction for Metallurgical Industry, University of Science and Technology Beijing, Beijing 100083, China

^* Corresponding author: yinsw@ustb.edu.cn

Published online: 30 June 2017

Abstract

Fine silicon particles (mean size of 2.7 μm) are used as entrained materials, and the entrainment characteristics of fine particles are investigated in a cylindrical fluidized-bed (inner diameter of 28 mm and height of 1000 mm) under high speed airflow. The effects of the volume flow of gas (Q, 1 m³/h to 2.5 m³/h), the number of holes (N, 1 to 4), the size of holes (D, 1 mm to 3 mm), and the distance between holes and the upper surface of the material layer (H, -100 mm to 200 mm) on the entrainment characteristics (entrainment rate W and entrained powder-gas ratio R) are experimentally studied through orthogonal experiment. The experimental results show that an increase in Q and H constantly improves the entrainment characteristics; a decrease in D enhances such characteristics, whereas the number of holes N has no significant effect on the entrainment characteristics. An optimal operating condition can result in optimal entrainment characteristics (W, 3.1 g/min and R, 0.058 g/g), which can be achieved with a Q of 2.5 m³/h, N of 1, D of 2 mm and H of 200 mm.