System for refining UMG Si using a steam plasma torch, comprising: a vacuum chamber; a cold crucible disposed within said vacuum chamber; a device for feeding UMG Si to said cold crucible; a steam plasma torch for applying steam plasma to the Si fed to said cold crucible, said steam plasma torch configured to form the steam plasma by introducing a reactive gas into plasma flame by an inert gas; characterized by further comprising an impurity collector for collecting impurity gas generated from said cold crucible and wherein said plasma torch includes an electrode rod having a predetermined length and formed with a tip at an end thereof and being electrically connected with an external cathode power supply; an internal cover surrounding said electrode rod in a longitudinal direction of said electrode rod with a first space formed between said internal cover and said electrode rod and being electrically connected with an external anode power supply; an external cover surrounding said internal cover in the longitudinal direction with a second space formed between said external cover and said internal cover; a nozzle cover unit having an internal nozzle cover connected with said internal cover and an external nozzle cover connected with said external cover, said internal nozzle cover covering the tip and having a horizontal nozzle end formed at a lower end thereof, said horizontal nozzle end being formed with a first orifice, said external nozzle cover covering said internal nozzle cover excerpt for said horizontal nozzle end and having a open bottom and a vertical nozzle end vertical to said horizontal nozzle end at a lower end thereof, the vertical nozzle end formed along a circumference of said horizontal nozzle end to the open bottom of said external nozzle cover, said vertical nozzle end being formed with a second orifice(s) in the upper part thereof and a third orifice(s) in the lower part thereof, wherein to said first orifice an inert gas for generation of plasma is fed through said first space to the second orifice a reactive gas for formation of steam plasma is fed through a tube installed in said second space and to said third orifice an inert gas for generation of plasma is fed through said second space. a vacuum chamber; a cold crucible disposed within said vacuum chamber; a device for feeding UMG Si to said cold crucible; a steam plasma torch for applying steam plasma to the Si fed to said cold crucible, said steam plasma torch configured to form the steam plasma by introducing a reactive gas into plasma flame by an inert gas; characterized by further comprising an impurity collector for collecting impurity gas generated from said cold crucible and wherein said plasma torch includes an electrode rod having a predetermined length and formed with a tip at an end thereof and being electrically connected with an external cathode power supply; an internal cover surrounding said electrode rod in a longitudinal direction of said electrode rod with a first space formed between said internal cover and said electrode rod and being electrically connected with an external anode power supply; an external cover surrounding said internal cover in the longitudinal direction with a second space formed between said external cover and said internal cover; a nozzle cover unit having an internal nozzle cover connected with said internal cover and an external nozzle cover connected with said external cover, said internal nozzle cover covering the tip and having a horizontal nozzle end formed at a lower end thereof, said horizontal nozzle end being formed with a first orifice, said external nozzle cover covering said internal nozzle cover excerpt for said horizontal nozzle end and having a open bottom and a vertical nozzle end vertical to said horizontal nozzle end at a lower end thereof, the vertical nozzle end formed along a circumference of said horizontal nozzle end to the open bottom of said external nozzle cover, said vertical nozzle end being formed with a second orifice(s) in the upper part thereof and a third orifice(s) in the lower part thereof,