Design and construction of a pci rig for evaluation of pulverized fuels combustion: equipment features

Abstract

Pulverized coal injection (PCI) is a technique worldwide used in blast furnaces (BFs) to reduce coke consumption. Burning of pulverized coal injected into tuyeres of BFs takes place under medium pressure (up to 450 kPa), high flame temperatures (around 2500 K), very fast heating rates (105–106 K/s) and very short residence times, less than 40 ms. Since there are no standard tests for evaluation of coal combustibility at PCI conditions, lab scale injection rigs are usually employed for this purpose. This work shows relevant characteristics of the injection rig developed by LASID-UFRGS, which operates at automated injection mode. The main rig features are direct measurement of pressure and temperature inside the combustion zone during combustion process, temperature measurement with ultra-fast thermocouples (ms), high speed control and data acquisition (ms) and collection of both solid and gaseous combustion products. First results showed pressure and temperature evolution along throughout the combustion test, with and without sample, combustion gas composition and coal burnout for different coals. Experimental data statistics showed good repeatability for all tested coals. Keywords: Pulverized coal injection; Coal combustion; Injection rig; Blast furnace raceway.