Retractable plasma torch for gasification reactors

Abstract

An apparatus comprises: a gasifier vessel; an orifice in a wall of the gasifier vessel; a plasma torch; a torch support structure connected to the wall of the gasifier vessel and having an opening configured to receive the plasma torch, the torch support structure including a shroud gas spool configured to inject shroud gas into the opening and around the torch and an isolation valve configured to prevent gas flow between an internal environment of the gasifier and an external environment outside of the torch support structure when the plasma torch is retracted; and an actuator configured to extend the plasma torch into the gasifier vessel through the orifice and to retract the plasma torch from the gasifier vessel.

What is claimed is: 
     
         1 . An apparatus comprising:
 a gasifier vessel;   an orifice in a wall of the gasifier vessel;   a plasma torch;   a torch support structure connected to the wall of the gasifier vessel and having an opening configured to receive the plasma torch, the torch support structure including a shroud gas spool configured to inject shroud gas into the opening and around the torch and an isolation valve configured to prevent gas flow between an internal environment of the gasifier and an external environment outside of the torch support structure when the plasma torch is retracted; and   an actuator configured to extend the plasma torch into the gasifier vessel through the orifice and to retract the plasma torch from the gasifier vessel.   
     
     
         2 . The apparatus of  claim 1 , wherein the shroud gas spool is positioned between the gasifier vessel and the isolation valve. 
     
     
         3 . The apparatus of  claim 1 , further comprising:
 a build-up removal mechanism configured to remove solidified slag build-up on a surface of the plasma torch.   
     
     
         4 . The apparatus of  claim 3 , wherein the build-up removal mechanism comprises one or more of:
 a mechanical rapping device, a vibratory device, or a scraper.   
     
     
         5 . The apparatus of  claim 4 , wherein the scraper is mounted either within or external to the gasifier vessel. 
     
     
         6 . The apparatus of  claim 1 , wherein the actuator comprises:
 a hydraulic actuator, a pneumatic actuator, or an electric actuator.   
     
     
         7 . The apparatus of  claim 1 , further comprising:
 a refractory lining adjacent to an inner surface of the orifice.   
     
     
         8 . The apparatus of  claim 1 , wherein the support structure further comprises:
 a purge spool including first and second annular seals having openings for receiving the plasma torch, and a plenum between the first and second annular seals to prevent gas flow between the internal environment of the gasifier and the external environment outside of the torch support structure when the plasma torch is retracted but the isolation valve is not yet fully closed.   
     
     
         9 . The apparatus of  claim 8 , wherein the shroud gas spool is positioned between the gasifier vessel and the isolation valve, and the isolation valve is positioned between the shroud gas spool and the purge spool. 
     
     
         10 . An apparatus comprising:
 a gasifier vessel;   an orifice in a wall of the gasifier vessel;   a plasma torch;   a torch support structure connected to the wall of the gasifier vessel and having an opening configured to receive the plasma torch, the torch support structure including an isolation valve configured to prevent gas flow between the internal environment of the gasifier and the external environment outside of the torch support structure when the plasma torch is retracted, and a purge spool having first and second annular seals with openings for receiving the plasma torch, with a plenum between the first and second annular seals to prevent gas flow between an internal environment of the gasifier and an external environment outside of the torch support structure when the plasma torch is retracted but the isolation valve is not yet fully closed; and   an actuator configured to extend the plasma torch into the gasifier vessel through the orifice and to retract the plasma torch from the gasifier vessel.   
     
     
         11 . The apparatus of  claim 10 , further comprising:
 a build-up removal mechanism configured to remove solidified slag build-up on a surface of the plasma torch.   
     
     
         12 . The apparatus of  claim 11 , wherein the build-up removal mechanism comprises:
 a mechanical rapping device, a vibratory device, or a scraper.   
     
     
         13 . The apparatus of  claim 12 , wherein the scraper is mounted either within or external to the gasifier vessel. 
     
     
         14 . The apparatus of  claim 10 , wherein the actuator comprises:
 a hydraulic actuator, a pneumatic actuator, or an electric actuator.   
     
     
         15 . The apparatus of  claim 10 , further comprising:
 a refractory lining adjacent to an inner surface of the orifice.   
     
     
         16 . The apparatus of  claim 10 , wherein the isolation valve is positioned between the gasifier vessel and the purge spool.