Abstract: A method of cleaning, either continuously or intermittently, a pneumatically operated pulverized coal system by injecting into this system a stream of generally uniformly sized coke breeze particles. This coke breeze stream would abrade the interior surface of the pulverized coal system thereby cleaning it. Additionally, due to the high carbon content of the coke breeze, this substance will replace or displace a portion of the coal stream delivered to the furnace. Furthermore, such use of coke breeze will eliminate the need to dispose of this by-product in cases where alternative uses are not available.