Method and device for producing metal powder

Abstract

Raw metal is intermittently and continuously charged into a chlorination furnace, the raw metal and chlorine gas are reacted in the chlorination furnace to continuously generate metal chloride vapor, and the metal chloride vapor and hydrogen gas are reacted in a reduction furnace to continuously obtain metallic powder. Furthermore, the chlorination furnace in which the chlorination reaction is proceeding is weighed, and the charged amount of the raw metal to the chlorination furnace is controlled depending on the weighing result.

1 . A method for production of metallic powder, the method comprising: 
 charging raw metal into a chlorination furnace intermittently or continuously, reacting the raw metal and chlorine gas in the chlorination furnace to generate metal chloride vapor continuously;    continuously reacting the metal chloride vapor and hydrogen gas in a reduction furnace to obtain metallic powder;    weighing the weight of the chlorination furnace in which a chlorination reaction is proceeding; and    controlling an amount of the raw metal charged into the chlorination furnace according to the weighing result.    
   
   
       2 . The method for production of the metallic powder according to  claim 1 , wherein weight changing rate of the chlorination furnace is observed, and charged amount of the raw metal to the chlorination furnace is controlled depending on the changing rate.  
   
   
       3 . The method for production of the metallic powder according to  claim 2 , wherein the charged amount of the raw metal is temporarily and suddenly increased in the case in which the changing rate suddenly decreases.  
   
   
       4 . The method for production of the metallic powder according to  claim 2 , wherein the changing rate is measured, the charged amount of the raw metal into the chlorination furnace is automatically controlled according to the measurement, and chlorination reaction rate of the raw metal and the chlorine gas in the chlorination furnace is controlled.  
   
   
       5 . The method for production of the metallic powder according to  claim 1 , wherein the weight of the chlorination furnace is weighed by a load cell.  
   
   
       6 . The method for production of the metallic powder according to  claim 1 , wherein the entirety of a raw material hopper which charges the raw metal into the chlorination furnace is weighed.  
   
   
       7 . The method for production of the metallic powder according to  claim 1 , wherein the metal is nickel.  
   
   
       8 . The method for production of the metallic powder according to  claim 7 , wherein the metallic powder is nickel powder having an average particle diameter in a range from 0.01 to 1 μm.  
   
   
       9 . The method for production of the metallic powder according to  claim 8 , wherein the metallic powder is for a conductive paste.  
   
   
       10 . The method for production of the metallic powder according to  claim 8 , wherein the metallic powder is for a multilayer ceramic capacitor.  
   
   
       11 . A production device for the metallic powder, comprising: 
 a raw material hopper to charge raw metal;    a chlorination furnace to chlorinate the raw metal charged from the raw material hopper; and    a reduction furnace to reduce metal chloride vapor generated in the chlorination furnace;    wherein the raw material hopper and the chlorination furnace are communicated with a raw material charging pipe which charges the raw metal via a carrying valve for controlling charged amount thereof;    the chlorination furnace and the reduction furnace are communicated with a carrying pipe which carries metal chloride vapor generated in the chlorination furnace to the reduction furnace;    the chlorination furnace is comprising a chlorine gas charging pipe to charge chlorine gas inside;    the reduction furnace is comprising a nozzle to inject the metal chloride vapor inside, a hydrogen gas charging pipe to charge hydrogen gas inside, and a cooling gas charging pipe to charge inert gas for cooling the reduced metallic powder inside;    the producing device of the metallic powder further comprises a weighing method to weigh the entire weight of the chlorination furnace and a controlling method to control charged amount of the raw metal to the chlorination furnace depending on the weighing result of the weighing method.    
   
   
       12 . The production for device of metallic powder according to  claim 11 , wherein the controlling method monitors the changing rate of the weight of chlorination furnace, and controls the charged amount of the raw metal into the chlorination furnace depending on the changing rate.  
   
   
       13 . The production device for metallic powder according to  claim 12 , wherein the controlling method increases the charged amount of the raw metal temporarily and immediately in the case in which the changing rate is suddenly decreased.  
   
   
       14 . The producing device for metallic powder according to  claim 12 , wherein the controlling method measures the changing rate, controls the charged amount of the raw metal into the chlorination furnace automatically according to the measurement, and controls the chlorination reaction rate of the raw metal and the chlorine gas in the chlorination furnace.  
   
   
       15 . The production device for metallic powder according to  claim 11 , wherein the device further comprises a weighing means for weighing the weight of the entirety of the raw material hopper.  
   
   
       16 . The production device for metallic powder according to  claim 11 , wherein the weighing means is a load cell.  
   
   
       17 . The production device for metallic powder according to  claim 11 , wherein the metal is nickel.