1. Field of the Invention
The invention relates to the control of fume formation in steel mill blast furnace cast houses and more particularly to the suppression and mitigation of fumes from the iron troughs and the iron and the slag runners of the blast furnace casting system.
One of the most critical problems faced by the steel industry is the control of blast furnace cast house emissions. It is evident that the industry must develop new techniques for pollution controls if it is to obviate the substantial capital and operating costs associated with available technology for controlling blast furnace cast house emissions to levels required by governmental environmental protection agencies. Technology for emission reduction through gas cleaning exists and can be accomplished by a number of air pollution control devices which utilize exhaust and filtering equipment which collect and clean the fugitive air. However, it should be recognized that in the United States a great majority of the presently operating blast furnaces were built before 1960 and use the original cast houses in which there are spatial limitations toward retrofitting additional equipment such as pollution collection devices.
2. Description of Prior Art
The known prior art fume control systems which can be used in conjunction with steel mill blast furnaces are directed to the disposal of the fume after it has been generated.
U.S. Pat. No. 3,994,210 discloses method and apparatus by which jets in the form of moving curtains of air are utilized to control and direct the movement of fume from a fume-generating apparatus to an exhaust hood opening.
French Pat. No. 71.13332 is more specifically directed to the channeling of smoke emitted by molten cast iron as it is extracted from a blast furnace through the use of blower nozzles which laterally direct air curtains to limit lateral movement of the smoke and direct it to a ventilating head.
German Pat. No. 2,157,418 discloses an air cleaning device for the pouring platform of a blast furnace, which device comprises suction nozzles connected to a gas cleaner at the outlets of the filling hoppers and/or over the tap holes.
Additionally, there appears in the August 1979 issue of Iron and Steel Engineer, pp. 33-39, an article entitled "Blast Furnace Cast House Emission Control" by A. G. Nicola which sets forth the available technology for collecting the process fugitive emissions generated in the blast furnace cast house.
It is evident that most prior art fume pollution control systems are addressed to the ventilation or exhausting of fumes after they are formed, i.e., they are addressed to the effect rather than the cause.