Performance Characteristics of Electrocyclone With Various Inlet Shapes

Abstract

In this study, the performance characteristics of electro-cyclone with different inlet shapes, such as helical, tangential and involute, were experimentally investigated. The range of particle size has 0.3 to 6 μm and the inlet velocities are 10, 15, 20, and 25 m/s. Particles used in this experiment are JIS Class 11 test powder which have the density of 1.9~2.1 g/cm3 and the mass median diameter of 2.3 μm. An electrocyclone has discharge wire which was inserted in the middle of vortex-finder. The length, diameter and material of discharge wire have 20 mm, 0.6 mm and SUS304, respectively. The discharge wire was applied with a voltage of 10 kV. The collection efficiency is calculated by the particle size distribution of the upstream and downstream using a laser optical particle counter. Pressure drops were measured between two pressure taps which were located at the inlet and outlet ducts of electrocyclone using a micromanometer. For the case of the involute type, due to a minimum turbulence, the retention time of particles becomes long in electrocyclone and particles have more chances to be charged. However, the experimental results show that a helical shape has a better collection effect than the other shapes. And the pressure drop of the involute shape for a given inlet velocity is smaller than the other shapes. The collection efficiency and the pressure drop with various inlet shapes and velocity changes in electrocyclone are graphically depicted.