Blast furnace charging method and apparatus

Apparatus for the delivery of materials to a shaft furnace comprising:

• at least a first storage hopper for providing intermediate storage for a charge of materials to be delivered to a furnace, said storage hopper having a supply port and a discharge port;
• frame means affixed to the furnace;
• weight measuring means supporting said first storage hopper from said frame means, said weight measuring means including a plurality of weighing devices displaced about the periphery of said storage hopper with respect to one another;
• a tubular feed spout, said feed spout having a cylindrical shape and being connected at its first end to the furnace;
• a conical flow directing member;
• an expandable compensating member hermetically coupling the second end of said feed spout to the smaller diameter end of said conical member;
• a retaining ring affixed to the exterior of said storage hopper about the discharge port therein;
• discharge channel housing means, said channel housing means connected at a first end to said conical member adjacent the larger diameter end thereof;
• a metering valve positioned in said discharge channel housing means for controlling the flow of material from said storage hopper to said feed spout second end;
• and
• means hermetically connecting said retaining ring to said housing means adjacent a second end thereof.

Apparatus for the delivery of materials to a shaft furnace comprising:

• at least a first storage hopper for providing intermediate storage for a charge of materials to be delivered to a furnace, said storage hopper having a supply port and a discharge port;
• frame means affixed to the furnace;
• weight measuring means supporting said first storage hopper from said frame means, said weight measuring means including a plurality of load cells displaced about the periphery of said storage hopper with respect to one another;
• longitudinally expandable feed spout means, said feed spout means communicating at a first end with said furnace;
• discharge channel housing means connected at a first end to said feed spout means second end;
• a retaining ring affixed to the exterior of said storage hopper about the discharge port therein;
• means hermetically connecting said retaining ring to the second end of said discharge channel housing means;
• a metering valve positioned in said discharge channel housing means for controlling the flow of material to said feed spout second end;
• and
• means for biasing said weight measuring means load cells to insure operation thereof in the positive range, said biasing means each comprising:
• a pair of helical springs coupled to the load cell, said springs being in compression;
• and
• means for adjusting the tension of each of said springs.

The method of supplying charge material to a shaft furnace, the furnace being provided with at least one intermediate storage hopper for storing a charge of material to be fed to the furnace and a distributing device disposed in the furnace so as to be supplied from the storage hopper, the method comprising the steps of:

• loading the storage hopper with charge material, the hopper being at atmospheric pressure and being isolated from the interior of the furnace during loading;
• sealing the interior of the hopper from the ambient atmosphere;
• pressurizing the hopper to the pressure level existing in the furnace;
• discharging the charge material from the hopper subsequent to pressurization thereof;
• measuring the quantity of material in the hopper during the discharge thereof;
• exercising control over the delivery to the furnace interior of charge materials being discharged from the hopper as a function of the instantaneous quantity of material in the hopper as obtained from the measuring thereof;
• providing force compensation during charging and discharging of the hopper whereby the quantity measurement will not be adversely affected by the furnace operating conditions;
• and
• maintaining a flexible hermetic seal between the exterior of the hopper and the exterior of the furnace to compensate for relative displacements of the hopper and furnace resulting from furnace operating conditions.