Abstract: Disclosed is a method for firing a kiln as well as a method for producing cement clinker in which pulverized coal is initially entrained in an airflow of about 2% of the theoretical amount of air needed to combust the coal and transport it to a burner. Supplemental primary air heated sufficiently to vaporize volatiles in the coal is mixed with the coal flow in a burner, discharged into the kiln and hence ignited. Secondary combustion air heated to between 800.degree. F. to 1650.degree. F. and more is added in the kiln to effect the substantially complete combustion of the pulverized coal in the kiln.

Abstract: Disclosed is a method for firing a kiln as well as a method for producing cement clinker in which pulverized coal is initially entrained in an airflow of about 2% of the theoretical amount of air needed to combust the coal and transport it to a burner. Supplemental primary air heated sufficiently to vaporize volatiles in the coal is mixed with the coal flow in a burner, discharged into the kiln and hence ignited. Secondary combustion air heated to between 800.degree. F. to 1650.degree. F. and more is added in the kiln to effect the substantially complete combustion of the pulverized coal in the kiln.

Abstract: A furnace includes a downdraft combustion chamber, a burner mounted at the top of a combustion chamber for burning particulate ash-containing fuel, and a generally horizontal duct near the lower end of the combustion chamber for withdrawing hot gases rsulting from the combustion. The combustion chamber is downwardly tapered to a relatively small conduit, downward into which molten slag from the ash flows. The slag, upon passing through the conduit, passes into and through a downwardly open slag-receiving chamber below the combustion chamber. The slag falls through out the bottom of the slag-receiving chamber into a volume of water immediately below. A portion of the hot gases is diverted through the slag-receiving chamber in order to maintain the slag-receiving chamber at a sufficiently high temperature so that the slag passing therethrough is prevented from solidifying. The portion of hot gas is then directed to a mill for drying fuel therein prior to combustion.

Abstract: An oil fired burner adapted to produce a variable asymmetrical flame shape. The burner includes a tip head carrying a plurality of tips disposed in at least two orientations, i.e., axial and off-axis. The relative rates of fuel supply to the tips is controlled to afford asymmetric flame shaping. In a typical application in a rotary cement kiln, the flame is biased to increase the heat transferred to the load in the front end of the kiln and to decrease the heat transferred to the top and sides of the kiln.