Image Number 11 for United States Patent #4790516.
A reactor for iron making having an upper gas blowing nozzle, a lower gas blowing nozzle, and an iron scrap charging inlet. A vertical shaft is installed directly above the inlet at the top part of the reactor. A mechanism is provided in the lower end of the vertical shaft for controlling charging of the iron scrap to the reactor. A by-pass tube is connected between the top part of the reactor and a gas inlet in the vertical shaft directly above the mechanism for controlling the charging of iron scrap and permits exit of high temperature exhaust gases from the reactor and introduces the exhaust gases to flow through the iron scrap in the vertical shaft to pre-heat the same. Structure is provided in the by-pass tube for introducing oxygen gas or air into the high temperature exhaust gases to react therewith and generate further heat. The structure can comprise a nozzle. The mechanism for controlling charging of iron scrap can include a damper positioned immediately above the inlet in the top part of the reactor which is movable to open and close the vertical shaft together with a stopper positioned above the damper and movable to open and close the vertical shaft. Certain amounts of iron scrap can thereby be charged to the reactor by sequential openings and closings of the damper and the stopper.