Method and system for high-temperature waste treatment

A method for treating waste, the method comprising:

• conveying waste into a waste treatment chamber;
• applying a plasma torch to heat and volatilize at least a portion of the waste inside the waste treatment chamber;
• moving volatilized waste out of the waste treatment chamber as a waste gas stream;
• treating the waste gas stream with air pollution control equipment;
• dropping melted waste inside the waste treatment chamber into a hearth receiving and holding the melted waste;
• operating the plasma torch to further heat the melted waste held by the hearth;
• separating the melted waste held by the hearth into at least two fractions (1) a first melt fraction having a first specific gravity and (2) a second melt fraction having a second specific gravity less than the first specific gravity of the first melt fraction;
• tilting the hearth in a first direction to remove at least a portion of the first melt fraction from the hearth via a first outlet;
• and
• tilting the hearth in a second direction to remove at least a portion of the second melt fraction from the hearth via a second outlet.

A system for treating waste, the system comprising:

• a waste treatment chamber;
• a waste feed system configured to conduct waste into the waste treatment chamber;
• a heat source configured to heat and melt the waste inside the waste treatment chamber;
• and
• a hearth receiving dripping waste melted by the heat source and holding melted waste during additional heating, the hearth including an underflow weir dividing the hearth into a first portion having a first depth for holding melted waste of lesser density and a second portion having a second depth greater than said first depth for holding melted waste of greater density.

Apparatus for treating waste, the apparatus comprising:

• a waste treatment chamber;
• a conveyor configured to conduct waste into the waste treatment chamber;
• a heat source configured to heat and melt the waste inside the waste treatment chamber;
• and
• a hearth configured to hold dripping waste melted by the heat source, said waste melted comprising fractions of different densities separated by an underflow weir provided in the hearth;
• wherein the heat source includes:
• a plasma torch;
• a first electrode configured for electrical contact with melted waste held by the hearth;
• and
• a second electrode also configured for electrical contact with the melted waste;
• wherein the plasma torch is operable to generate an electrical current between the plasma torch and either of the electrodes.

A hearth for use in a waste treatment system, the hearth comprising:

• a container configured to hold melted waste;
• a first electrode configured for electrical contact with the melted waste;
• a first outlet;
• a second outlet;
• an underflow weir in proximity with the first outlet, said underflow weir situated between a first section configured for holding melted waste of lesser density and a second section configured for holding melted waster of greater density;
• and
• a second electrode configured for electrical contact with the melted waste in proximity with the underflow weir.