Industrial Opportunity

Technical Service for Granular Flow Control in Your Environment


Our particle characterization instrument (ECT, Electrometer, MPCT, Faraday Cage, particle shape analyzer, particle size analyzer, flowability meter and mini spray dryer) Package provides fast economical answers for the control and certification of the hydrodynamic and electrostatic characteristics of granular material in a pneumatic conveying system. Testing is performed in accordance with established guidelines as specified in industry and customized to meet special customer requirements. Consulting services are available to perform on-site product testing and facility audits plus production line and material transport monitoring.

 What can we do?

o       Monitor and assess hydrodynamic capabilities of granular flows;

o       Detect electrostatics of granular flows;

o       Measure and assess charge generation of particles with various sizes and shapes;

o       Handle sparking due to discharging in a pneumatic conveying system;

o       Analyze particle attrition during granular pneumatic conveying.

What have we done?

o       Investigated gravity-driven granular flow through a vertical pipe using ECT (1999);

o       Monitored pneumatic conveying in horizontal ducts using ECT (2001);

o       Studied pneumatic conveying of granular solids in vertical and inclined risers using ECT (2003);

o       Studied electrostatics of pneumatic conveying of granular materials using ECT, MPCT (2004);

o       Studied electrostatic charge generation and its effects on granular flow behavior in a pneumatic conveying system using Electrometer, MPCT and Faraday Cage (2004).


Our consulting services bring solutions to many hydrodynamic and electrostatic related problems in virtually all industries where granular hydrodynamics and static electricity can affect productivity or safety. We will apply our extensive experience and expertise while performing on-site product testing, facility audits, production line and material transport monitoring. We provide product development assistance that can reduce or eliminate hydrodynamics and electrostatics related problems during manufacture, transporting and end-user applications.


Technical Seminars provide training in all areas of granular hydrodynamic and electrostatic measurement and control. They can be presented at either clients or our facilities. Presentations by experienced personnel are tailored to each client’s specific requirements in such diverse fields as conveying system assembly, transporting and granular material operations plus spark accident handling. Demonstrations and all necessary  instrumentation are included in every seminar.

Particle characterization instrument Package

ECT: Electrical Capacitance Tomography (ECT) is a powerful instrument which enables online process information to be collected for highly complex multiphase systems in a non-invasive way.

ECT system and the data acquisition module (Process Tomography, Wilmslow, Cheshire, U.K.)

ECT sensor and AC-ECT system (ECT Instruments Ltd, U.K.)

Electrometer: With its high measuring sensitivity, the R8252 provides precise evaluation of basic electrical characteristics such as current levels, voltage, resistance, and charge, and has the flexibility to measure everything from devices with ultra-low currents to devices with high voltages and resistances.

Advantest R8252 Digital Electrometer (Advantest Corporation, Japan)

MPCT: Modular Parametric Current Transformer (MPCT) works on the principle of the zero-flux DC current transformer (DCCT). The DC component of the current flowing through the toroid sensor is detected by a magnetic modulator, also called fluxgate or second-harmonic detector. The AC component is detected by an active Hereward transformer. The two circuits are cascaded in a common feedback loop to generate a magnetic flux which always cancels the primary current flux. The MPCT output is the voltage developed by the feedback current passing through a precision resistor.

Modular Parametric Current Transformer (Bergoz Instrumentation, France)

Faraday Cage: A Faraday cage is best understood as an approximation to an ideal hollow conductor. Electric fields produce forces on the charge carriers (i.e., electrons) within the conductor. As soon as an electric field is applied to the surface of an ideal conductor, it generates a current that causes displacement of charge inside the conductor that cancels the applied field inside.

TR8031 Faraday Cage (Advantest Corporation, Japan)

Other instruments:

Chemical Looping Gasifier

Plastic pyrolysis and gasification system

Waste oil or bio-oil reforming system

Particle shape analyzer

SYMPA Particle size analyzer system

ERWEKA flowability meter and BUCHI mini spray dryer


Team member:

Wang Chi-Hwa:   Ph.D. Professor Department of Chemical and Biomolecular Engineering, National University of Singapore

How to contact us:

Professor Wang Chi-Hwa:    (O) 65-65165079; Email:


Hua, J. S., C. H. Wang. Electrical capacitance tomography measurements of gravity-driven granular flows. Industrial and Engineering Chemistry Research, 38(3), 621 30. 1999.

Lee, L. Y., T. Y. Quek, R. S. Deng, M. B. Ray, C. H. Wang. Pneumatic transport of granular materials through a 90 degree bend. Chemical Engineering Science, 59(21), 4637 651. 2004.

Rao, S. M., K. Zhu, C.-H. Wang, S. Sundaresan. Electrical capacitance tomography measurements on the pneumatic conveying of solids. Industrial and Engineering Chemistry Research, 40(20), 4216 226. 2001.

Yao, J., Y. Zhang, C. H. Wang, S. Matsusaka, H. Masuda. Electrostatics of the granular flow in a pneumatic conveying system. Industrial and Engineering Chemistry Research, 43(22), 7181 199. 2004.

Zhu, K., S. M. Rao, C.H. Wang, S. Sundaresan. Electrical capacitance tomography measurements on vertical and inclined pneumatic conveying of granular solids. Chemical Engineering Science, 58(18), 4225 245. 2003.

Zhu, K., C. K. Wong, S. M. Rao, C.H. Wang. Pneumatic conveying of granular solids in horizontal and inclined pipes. AIChE Journal, 50(8), 1729 745. 2004a.

Zhu, K. S. M. Rao , Q.H. Huang, C.H. Wang, S Matsusaka, and H. Masuda, On the Electrostatics of Pneumatic Conveying of Granular Materials Using Electrical Capacitance Tomography, Chem. Eng. Sci., 59(15) 3201-3213, 2004b.

J. Yao, Y. Zhang, C.H. Wang, S. Matsusaka, H. Masuda, Electrostatics of the Granular Flow in a Pneumatic Conveying System, Ind. Eng. Chem. Res., 43, 7181-7199 (2004).

J. Yao and C.H. Wang, Granular size and shape effect on electrostatics in pneumatic conveying systems, Chemical Engineering Science, 61, 3858-3874 (2006).

J. Yao, Y. Zhang, C.H. Wang, C.Y. Liang, On the Electrostatic Equilibrium of Granular Flow in Pneumatic Conveying Systems, AIChE Journal, 52 (11) 3775-3793 (2006).

Y. Zhang and C. H. Wang, Particle Attrition due to Rotary Valve Feeder in a Pneumatic Conveying System: Electrostatics and Mechanical Characteristics, Canadian Journal of Chemical Engineering, 84, 663-679 (2006).

Y. Zhang, W.C. Lim, and C.H. Wang, Pneumatic Transport of Granular Materials in an Inclined Conveying Pipe: Comparison of CFD-DEM, ECT and PIV Results, Ind. Eng. Chem. Res., 46, 6066-6083 (2007).

Y. Zhang, Y.C. Liang and C. H. Wang, Hazard of Electrostatic Generation in Pneumatic Conveying System: Electrostatic Effects on the Accuracy of Electrical Capacitance Tomography Measurements and Generation of Spark, Measurement Science and Technology, 19, 015502 (2008).

A. Rezvanpour, C.H. Wang, Y.C. Liang, W. Yang, Investigation of droplet distribution in electrohydrodynamic atomization (EHDA) using AC-based electrical capacitance tomography (ECT) system with internal-external electrode sensor, Measurement Science and Technology, 23, 015301 (2012).

Y. Cheng, E.W.C. Lim, C.H. Wang, G. Guan, C. Fushimi, M. Ishizuka, A. Tsutsumi Electrostatic Characteristics in a Large-Scale Triple-Bed Circulating Fluidized Bed System for Coal Gasification, Chem. Eng. Sci., 75, 435-444 (2012).

Y. Cheng, D.Y.J. Lau, G. Guan, C. Fushimi, A. Tsutsumi, C.H. Wang, Experimental and Numerical Investigations on the Electrostatics Generation and Transport in the Downer Reactor of a Triple-Bed Combined Circulating Fluidized Bed, Industrial & Engineering Chemistry Research, 51 (43), 14258 14267 (2012).