The steel industry in March 1998 issued a comprehensive publication entitled “Steel Industry Technology Roadmap,” and on page 11, it states the following:                The ultimate objective in the iron smelting area is to develop a coal-based process that produces liquid iron directly from coal and ore fines or concentrate. Liquid iron is preferred to solid iron because there is no gangue and it retains its sensible heat. Coal is obviously preferred over coke or natural gas because of its abundance and lower cost. If possible, the use of fines or concentrate will eliminate agglomeration costs. These new processes should have a high smelting intensity or productivity. High productivity and the elimination of cokemaking and agglomeration will significantly reduce capital costs.In substance, the Roadmap's ultimate objective was, and still is, to substitute several plants, shown within the blue enclosure of Exhibit 1, with one single efficient plant. The Applicant conceived the subject matter disclosed in the reference patent as a solution to the ultimate objective of producing liquid iron directly wherein coal and ore fines or concentrate are used; a patent application was filed, and the reference patent was issued.        
To put the concept into practice, a pilot was constructed (Exhibit 2) and tests were initiated. A multitude of problems were discovered. The most serious problems consisted of the following:
No 1. Sporadic explosions caused by super-heated steam generated from water leakage from the melt-down of the stainless steel outer tube (sheath) at the copper tip of the water-cooled, oxygen injection lance (Exhibit 3), which endangered operating personnel, one of whom experienced severe burns, necessitating a hospital stay. To prevent the melting of the stainless sheath, steps were taken to increase the size of the copper tip. Unfortunately, excessive build-up at the tip of the lance occurred (Exhibit 4), resulting in destroying the flow pattern of the oxygen.
No 2. The uniform flow of the gas containing oxygen from the tip of the lance is most critical in order to produce a uniform product, an iron/carbon intermediate of some 50% metallization with about 6% carbon is suitable for conversion into carbon-saturated liquid iron of blast furnace specification. The problems caused by the build-up at the tip of the lance included premature melting, over-oxidation, too low in metallization, and completely unreduced feed material:
No 3. Excessive heat loss occurred within the horizontal reactor, especially toward its discharge end, caused by the cooling effect from the water-cooled lance.
No 4. Build-up at the discharge end of the horizontal reactor itself persisted (Exhibit 5), resulting in a physical blockage that prevented the advancement of the contents of the horizontal reactor by means of the pushing ram of the charger, thus forcing unscheduled shutdowns.
No 5. Build-up downstream of the horizontal metalizing reactor and upstream of the storage was also experienced in the vertical section where the homogenizer/melter would be located, causing shutdowns that entailed moving equipment to provide access to poke hot, built-up material with a bar to unplug the build-up; Exhibit 6.
No 6. Iron/carbon intermediate that was fed to the melting furnace, being lighter than the liquid iron, would float on top of the molten bath (Exhibit 7) and dwell there, instead of entering into solution with the metal in the molten bath, such flotation of intermediate preventing the rapid and complete conversion of the intermediate into liquid iron.
In addressing problems No 1, No 2, and No 3, it was decided to relocate the injection lance to be introduced from the cold end through the charger of the horizontal metallizing reactor, as shown in Exhibit 8, together with increasing the pressure of injection of the gas containing the oxygen to create a forceful jet from the tip of the lance to reach all the way to the discharge end of the horizontal metalizing reactor, with the tip of the lance being located where the temperature of the iron ore and ash are below their incipient fusion. This required the construction of a new charger (Exhibit 9), wherein a provision was made for the lance to pass through the center of the mandrel, resulting in a structure of the lance being disposed through the mandrel and the mandrel through the pushing ram.
In addressing problem No 4, which relates to the blockage created by build-up at the discharge end of the metallizing reactor, the new charger was constructed structurally more robust than the initial one, and also the hydraulic pressure was raised by adding a booster hydraulic pump with new controls (Exhibits 10A and 10B) to increase the pushing force of the new charger in order to surmount blockage.
In addressing problem No 5, to prevent build-up downstream of the metalizing reactor and upstream of the storage, it was decided to completely eliminate the homogenizer/melter (numeral 11), described in the referenced patent, and perform the melting of the iron/carbon intermediate in an induction channel furnace (ICE) as that made by Ajax Magnethermic, with certain modifications as would be described in detail hereinafter, to serve both as a melter as well as storage of liquid iron.
In addressing the issue of the intermediate flotation on top of the molten bath, a vertically oscillating mechanical dunker was developed (Exhibit 11A) which was equipped with a graphitic block (Exhibit 11B) which is adapted to force the floating intermediate to be submerged below the level of the high-temperature bath where the carbon in the intermediate completes the reduction of the unreacted oxides of iron, namely, Fe2O3, Fe3O4, and FeO, which have not reacted in the horizontal metallizing reactor.
With the changes made, the Applicant was successful in overcoming the problems mentioned hereinbefore and producing an acceptable intermediate into which carbon from the coal is integrally imbedded within the metallized iron made from ore fines or concentrate in the horizontal metalizing reactor (Exhibit 12).
Further, two valuable gases are co-produced: one during the metallization of the iron ore in the horizontal metallizing reactor and a second during the melting of the intermediate (Exhibit 13).
To summarize the above, the Applicant, in effect, has invented a method and apparatus adapted to accept various proportions of ore and coal and yet produce a liquid iron (Exhibit 13) by way of producing an intermediate whose composition is quite suitable to be converted to liquid iron that can be subsequently converted into low-cost steel.
USPTO Backgrounds
USPTO Backgrounds