Start-up torch

An apparatus comprising:

• a tuyere including a tubular chamber having an internal wall defined by a mandrel;
• a plasma torch assembly including a torch positioned to inject hot gas into the tuyere and having a tubular structure that extends along an axis of the chamber and includes an end positioned adjacent to an outlet end of the chamber;
• the plasma torch assembly further including a shroud head configured to inject shroud gas between the internal wall of the chamber and the tubular structure of the torch in a direction tangentially disposed with respect to the chamber wall;
• a pipe positioned around at least a portion of the mandrel forming a plenum at least partially encircling the mandrel;
• and
• a plurality of nozzles in the chamber internal wall configured to inject a combustible material from the plenum to a space between the internal wall of the chamber and the tubular structure of the torch, wherein the plurality of nozzles are configured to deliver the combustible material upstream of a plasma plume produced by the torch allowing premixing of the shroud gas and the combustible material in the space between the internal wall of the chamber and the tubular structure of the torch prior to ignition by the plasma plume.