APPARATUS AND METHOD TO IMPROVE PULVERIZER AND REDUCE NO_ EMISSIONS IN COAL-FIRED BOILERS

摘要

An apparatus and method to improve pulverizer operation and reducenitrogen oxide emissions from furnaces which burn pulverized coal from at least onepulverizer. A duct type burner burns a fuel in the primary air which heats theprimary air supplied to the pulverizers. The combustion increases the primary airtemperature and improves the drying of the coal, thus improving the pulverizerthroughput and/or the fineness of the pulverized coal. Operation of the duct burneralso reduces the oxygen in the primary air. The reduction in oxygen reduces thepropensity of the coal to ignite in the pulverizers and cause fires or even explosions.The reduced oxygen in the primary air also reduces NOx formation.