Sealing mechanism of feeding device

Abstract

The present invention provides a sealing mechanism of a feeding device for feeding lumps and/or powder to a moving-hearth heating furnace. The feeding device includes a vibrating feeder having a trough in which a hole for feeding the lumps and/or powder to the furnace is formed and a duct for guiding the lumps and/or powder dropped through the hole to a hearth of the heating furnace. The sealing mechanism includes a water sealing mechanism having a skirt plate, a weir plate, a side surface of the duct, and liquid. The skirt plate is provided on the lower surface of the trough. The weir plate is provided above a ceiling of the heating furnace. The liquid is kept in a tank serving as a pool of liquid which is formed by the side surface of the duct and the weir plate.

What is claimed is:  
     
         1 . A sealing mechanism of a feeding device for feeding lumps and/or powder to a moving-hearth heating furnace, the feeding device comprising: 
 a vibrating feeder including a trough in which a hole for feeding the lumps and/or powder to the furnace is formed; and    a duct for guiding the lumps and/or powder dropped through the hole to a hearth of the heating furnace,    the sealing mechanism comprising: 
 a water sealing mechanism including a skirt plate, a weir plate, a side surface of the duct, and liquid,  
   wherein the skirt plate is provided on the lower surface of the trough such that the skirt plate surrounds the periphery of the upper end of the duct and such that the lower end of the skirt plate is positioned below the upper end of the duct,    the weir plate is provided above a ceiling of the heating furnace such that the weir plate surrounds the periphery of the lower end of the skirt plate and such that the upper end of the weir plate is positioned above the lower end of the skirt plate, and    the liquid is kept in a tank serving as a pool of liquid which is formed by the side surface of the duct and the weir plate such that the liquid surface is above the lower end of the skirt plate.    
     
     
         2 . The sealing mechanism according to  claim 1 , wherein the pool of liquid is formed in an area including a feeding nozzle of the trough when viewed from a side.  
     
     
         3 . The sealing mechanism according to  claim 1 , wherein the pool of liquid is formed in an area including the width of the hearth below the trough when viewed from the top.  
     
     
         4 . The sealing mechanism according to  claim 1 , wherein a feeding nozzle is formed in the lower side of the trough such that the nozzle extends downward along the edge of the opening of the hole in the vibrating feeder and the upper end of the duct is positioned between the lower end of the feeding nozzle and the lower surface of the trough.  
     
     
         5 . The sealing mechanism according to  claim 1 , wherein at least one inlet for feeding the liquid and at least one outlet for discharging the liquid is provided in the tank formed by the side surface of the duct and the weir plate.  
     
     
         6 . The sealing mechanism according to  claim 1 , wherein the liquid is continuously or intermittently fed to or discharged from the tank formed by the side surface of the duct and the weir plate.  
     
     
         7 . The sealing mechanism according to  claim 1 , wherein a rotary hearth furnace is used as the moving-hearth heating furnace.  
     
     
         8 . The sealing mechanism according to  claim 7 , wherein the rotary hearth furnace is used for producing metallic iron by reducing iron oxide.