Enhanced pulverized coal mass flow measurement

Two methods of coal flow measurement are described in this article for a pulverized coal injection (PCI) process into blast furnaces. The original coal flow design is based on vessel weight variation along the time, a moving average and an ordinary PID controller. Enhanced coal flow devices of mass solid correlation with an auto-calibration unit were specially designed and installed in the main conveying pipeline of three coal injection stations. Therefore, the PCI plant now takes advantage of each measurement and chooses the best for safety interlocks and control.

► Mass flow meter for pulverized coal injection based on sensors for density and speed.
► Auto-calibration function based on an external signal from load cells system.
► Auto-calibration to avoid error in flow measurement after coal’s chemical changes.
► Increasing of the coal mass flow accuracy from 5% down to less than 2%.
► New pulverized coal flow loop control and stability for blast furnaces.