GB1038986A - A cooling and cleaning plant for waste gas from steel-producing furnaces - Google Patents

Abstract

1,038,986. Waste heat steam boilers; thermal regenerators. WAAGNER-BINO A.G. April 3, 1963 [April 3, 1962], No. 13130/63. Headings F4A and F4K. Above each of a plurality of converters 1 or like steel-making furnaces, a hood 2 is provided in which the furnace gases are burnt with a forced flow of combustion air supplied to the hood through ports 3, all the gases then being directed through a common duct 11 from which they divide to flow either directly (Fig. 1, not shown), or through a branch duct 20 to two or more simultaneously operable heat absorbing units 6 and dust extraction units 7 before passing to a chimney 9. The heat absorbing units 6 may comprise steam generating units, but may include a direct contact injection cooler 46 (Fig. 6, not shown). The converters 1 are of the kind employing an oxygen lance 17. The units 6 together comprise a waste heat boiler and each consists of steam generator, superheating and economizer sections 23, 24, 25. The duct 11 is lined with steam or hot water tubes 12 and the steam from all sources is collected in a drum 10. Inoperative units 6 may be isolated from the waste gas stream by slide dampers 28. Other slide dampers 4 enable individual converters to be isolated for discharging, recharging, and repair as necessary. Additional burners 13 are used to boost the heat to the units 6 when the heat supply from the converters is insufficient. Also as described with reference to Fig. 4, the branch duct 20 contains checker brickwork 21 which is normally heated by the furnace waste gases. During periods when no heat is being supplied by the converters, this absorbed heat is given up to air passed through the channel 20 to a burner 13 at the downstream end thereof for maintaining a constant temperature at the inlet to the steam generator sections 6. The air is supplied to the channel 20 either by way of hoods 2 and duct 11 or, if the dampers 4 are closed, through a valve 22. A slag trap 18 is provided immediately downstream of each furnace hood 2. The checker bricks may be made of carbon or graphite.