The gas/solid flow regime of dense-phase pneumatic conveying of pulverized coal under a pressure of 4.0 MPa in horizontal pipeline 10 mm in diameter,is monitored by electrical capacitance tomography (ECT) using 8 electrodes.To improve the accuracy of the capacitance measurement,an AC-based singlechannel capacitance measuring circuit was developed,and a modified iterative Landweber algorithm was used to reconstruct the image.A two-fluid model based on the kinetic theory of granular flow was used to study the three-dimensional steady-state flow behavior of dense-phase pneumatic conveying of pulverized coal.