Nickel powder production method and nickel powder production device

Abstract

Provided is a method with which it is possible to prevent equipment, such as piping and valves, used to discharge and recover a nickel powder-containing slurry from a high pressure reaction tank from being damaged and trapping the nickel powder therein and to enable continuous operation, thereby improving the productivity. This nickel powder production method comprises a step of reacting a nickel sulfate-amine complex solution with hydrogen gas under high pressure in a reaction tank, thereby obtaining a nickel powder slurry containing nickel powder. The method is characterized in that the nickel powder slurry is discharged and transferred through discharge piping from the reaction tank in which the nickel powder-containing slurry has been produced, and then a washing solution is supplied to the discharge piping at a predetermined pressure to wash the discharge piping.

1 . A nickel powder production method, the method comprising reacting a nickel sulfate-amine complex solution with hydrogen gas under a high pressure in a reaction tank to obtain a nickel powder slurry containing nickel powder, wherein
 the nickel powder slurry is discharged and transferred through discharge piping from the reaction tank in which the slurry containing nickel powder is produced, and then a washing solution is supplied to the discharge piping at a predetermined pressure to wash the discharge piping.   
     
     
         2 . The nickel powder production method according to  claim 1 , wherein the washing solution is supplied to the discharge piping at a pressure lower than an internal pressure of the reaction tank by 0.2 MPa to 1.0 MPa. 
     
     
         3 . The nickel powder production method according to  claim 1 , wherein a filtrate obtained by subjecting the recovered nickel powder slurry to solid-liquid separation is used as the washing solution. 
     
     
         4 . A nickel powder production device in which a nickel sulfate-amine complex solution is reacted with hydrogen gas under a high pressure to obtain a nickel powder slurry containing nickel powder, the device comprising:
 a reaction tank in which a nickel sulfate-amine complex solution is reacted with hydrogen gas to produce nickel powder;   a depressurization tank that depressurizes the nickel powder slurry discharged from the reaction tank to normal pressure;   discharge piping for connecting the reaction tank and the depressurization tank and discharging the nickel powder slurry from the reaction tank to the depressurization tank; and   washing piping that is connected to the discharge piping and supplies a washing solution to the discharge piping.   
     
     
         5 . The nickel powder production method according to  claim 2 , wherein a filtrate obtained by subjecting the recovered nickel powder slurry to solid-liquid separation is used as the washing solution.