Correlation of Electromagnetic Flow Meter, Electrical Resistance Tomography and Mechanistic Modelling for a New Solution of Solid Slurry Measurement

J. Y. Xu2, M. Wang1, B. Munir1, H. I. Oluwadarey1, H. I. Schlaberg1, Y. X. Wu2, and R. A. Williams1

1School of Process, Environmental and Materials Engineering, University of Leeds, Leeds, UK,

Email: M.Wang@leeds.ac.uk

2Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China

ABSTRACT

The study presented here was carried out to obtain the actual solids flow rate by the combination of electrical resistance tomography and electromagnetic flow meter. A new in-situ measurement method based on measurements of EMF and ERT to study the flow rates of individual phases in a vertical flow is proposed.

The study is based on laboratory experiments that were carried out with a 50 mm vertical flow rig for a number of sand concentrations and different mixture velocities. A range of sand slurries with median particle size from 212μm to 355μm was tested. The solid concentration by volume covered was 5% and 15%, and the corresponding density of 5% is 1078 kg/m3 and for 15% 1238 kg/m3. The flow velocity was between 1.5 m·s-1 and 3.0 m·s-1. A total of 6 experimental tests were conducted. The equivalent liquid model was adopted to validate in-situ volumetric solids fraction and calculate the slip velocity.

The results show that the ERT technique can be used in conjunction with an electromagnetic flow meter as a way of measuring slurry flow rate in a vertical pipe flow. However, it should be emphasized that the EMF results must be treated with reservation when the flow pattern at the EMF mounting position is a non-homogenous flow. The flow rate obtained by EMF should be corrected considering the slip velocity and the flow pattern.

Keywords slurry measurement, electrical resistance tomography, electromagnetic flow meter, in-situ mean volumetric fraction, slip velocity.