Review of certain key issues in indirect measurements of the mass flow rate of solids in pneumatic conveying pipelines

• Published in: Measurement : journal of the International Measurement Confederation Vol. 43; no. 6; pp. 727 - 734
• Main Authors: Zheng, Yingna, Liu, Qiang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2010
• Subjects: Arrays; Averaging effect; Gas pipelines; Gas–solids two-phase flow; Mass flow; Measurement methods; Meters; Moisture content; Pneumatic conveyors; Resolution and sensitivity; Sensors; Solids’ mass flow rate measurement; Spatial filtering effect; Averaging effect; Resolution and sensitivity; Gas–solids two-phase flow; Spatial filtering effect; Solids’ mass flow rate measurement
• ISSN: 0263-2241; 1873-412X
• DOI: 10.1016/j.measurement.2010.02.002

On-line mass flow measurement of particulate solids in pneumatic conveying pipeline is a technically challenging area, where mass flow measurement presents a range of problems. These problems are not normally relevant to a single phase flow, but are always involved in gas–solids two-phase flows, like inhomogeneous distribution of solids over the pipe cross section, irregular velocity profiles, variations in particle size, moisture content, and deposition of fine particles on the inner wall of the pipeline. These variables may affect the response of a solids flow meter in ill-defined ways. All of these make the design and the calibration of solids’ mass flowmeter more difficult. Based on a review of non-invasive mass flow measurements of particulate solids, this paper summarizes and highlights several key issues, which often rely on structures of sensors or measurement methods, in indirect mass flow metering of pneumatically conveyed solids. They are: (i) spatial filtering effect; (ii) averaging effect; (iii) measurement resolution and sensitivity of array structures in tomography sensors.