摘要 |
<p>The method of operating a furnace including the steps of conveying (30) pulverized coal in an air stream towards a furnace (10), separating (34) the stream into two portions (36,38), one being a fuel rich portion (38), and the other being a fuel lean portion (36), introducing (40) the fuel rich portion into the furnace in a first zone, introducing (42,44) air into the first zone in a quantity insufficient to support complete combustion of all of the fuel in the fuel rich portion, introducing (46) the fuel lean portion into the furnace in a second zone, introducing (48) air into the second zone in a quantity such that there is excess air over that required for combustion of all of the fuel within the furnace, and introducing (50) lime into the furnace simultaneously with the fuel, so as to minimize the peak temperature within the furnace, and also minimize the formation of NOx and SOx in the combustion gases.</p> |