E-SPART Analyzer: Its Performance and Applications to Powder and Particle Technology Processes

• Main Author: M.K. Mazumder
• Format: Article
• Language: English
• Published: Hosokawa Powder Technology Foundation 2014-05-01
• Series: KONA Powder and Particle Journal
• Online Access: https://www.jstage.jst.go.jp/article/kona/11/0/11_1993013/_pdf/-char/en

The characterization of electrostatic charge and aerodynamic size properties of particles and powders is of critical importance in many electrokinetic processes and research applications. Some of the major particle and powder technology processes that employ electrokinetics of particles are: 1) electrophotography, including laser printing and ink jet printing, 2) powder coating and electrosprays, 3) electrostatic beneficiation of coal and minerals and electrostatic precipitators, and 4) lung deposition of inhaled pharmaceutical aerosols. In these processes, dispersion, transport, and deposition of particles depends significantly upon the electrokinetic behavior of the particles, determined by (1) the aerodynamic diameter – a parameter that includes the particle size, shape, and density, (2) electrostatic charge – both the magnitude and polarity, and (3) fluid flow and electrical fields surrounding the particles. There are a number of instruments that can be used to characterize the aerodynamic size distribution of particles. Likewise instruments are available to estimate the net average electrostatic charge of particles sampled. However, choice of instruments for real-time simultaneous measurements of aerodynamic diameter and electrostatic charge distributions of particles on a single particle basis is limited. The Electrical Single Particle Aerodynamic Relaxation Time (E-SPART) analyzer can be used for simultaneous characterization of particle size distribution in the range from submicron to 100μm and particle charge distribution in the range from 0 to their saturation charge levels. We present a brief description of the principles of operation of the analyzer, its operational range, its advantages, and limitations. Application of the E-SPART analyzer to some powder technology processes is also briefly discussed, citing current research needs in these processes with examples of experimental investigations. In many of these processes, the E-SPART analyzer can be used to optimize the particle and powder technology processes involving electrokinetic properties of particles.