Low sulfur coal additive for improved furnace operation

摘要

The present invention is directed to additives for coal-fired furnaces, particularly furnaces using a layer of slag to capture coal particles for combustion. The additive(s) include iron, mineralizer(s), handling aid(s), flow aid(s), and/or abrasive material(s). The iron and mineralizers can lower the melting temperature of ash in low-iron, high alkali coals, leading to improved furnace performance.

主权项

1. A method of operating a solid fuel fired boiler, comprising:
introducing a solid fuel into the boiler, wherein the solid fuel is a coal having a sulfur content of less than about 1.5 wt. % (dry basis of the coal); introducing an iron-containing material into the boiler, wherein the iron-containing material is at least one of mill scale from steel production and dust from blast furnace gas cleaning equipment; and at least partially combusting the solid fuel to produce an ash slag, wherein, in the at least partially combusting step, at least one of the following is true: (i) the ash slag has a fluid temperature less than a fluid temperature characteristic of the ash slag produced from combustion of the solid fuel alone; and (ii) the ash slag has a melting point less than the melting point of a second ash slag produced from the combustion of the solid fuel alone.