Methods and apparatus for residual material management

A residual impurity management method comprising:

• directing a gaseous stream through an unlined portion of a pipe under at least one of a vacuum and a partial vacuum, wherein the gaseous stream comprises gaseous sodium, wherein the gaseous stream is at a temperature between 1400° C. and 2200° C.;
• allowing the gaseous stream to cool to between 900° C. and below 1400° C.;
• injecting a neutralizing agent into the gaseous stream at an injection point, wherein the injection point is located at a point where a portion of the sodium is not in gaseous form and wherein the gaseous stream is at a temperature of between 900° C. and below 1400° C.;
• conducting the gaseous stream through a heated portion of the pipe;
• and
• conducting the gaseous stream through a cooled portion of the pipe.