On-line measurement of pneumatic conveying of pulverized coal in pipes

Abstract

Running conditions of pulverized coal pipes and mills are of greatly effecting on the combustion and safely operation of utilities in coal-fired power plants. However, there are less effective ways to on-line measure or diagnose the pipes or mills. Based on light fluctuation method, the on-line measurement of size and concentration of pulverized coal were presented in this work. Moreover, the velocity of pulverized coal in pipes was measured by cross correlation method. A novel on-line monitoring system was designed with above measurement principles. The on-line monitoring system was applied to measure pulverized coal pipes and mills in-situ in a 1000MW ultra supercritical unit. The unit had 48 pulverized coal pipes and adopted three-layer opposed firing pattern. The experimental results showed the on-line monitoring system can simultaneously measure the size, concentration and velocity of pulverized coal in different coal pipes accurately and quickly. Using these parameters, the running condition of pulverized coal pipes and mills can be diagnosed. Therefore, this work provided a practical method and instrument for on-line monitoring technology of pulverized coal pipes and mills.