Apparatus and method for treating hazardous waste

A method for treating waste consisting of organic and inorganic components, comprising the steps of:

• providing a waste processing vessel having a processing chamber;
• feeding waste into said processing chamber at a controlled feed rate;
• providing a plasma arc torch;
• heating said waste in said processing chamber using said plasma arc torch to convert organic components of the waste to a gas comprising hydrogen, carbon monoxide and carbon dioxide, and to particulate including carbon particulate, and to convert inorganic components of the waste substantially to molten material,
• passing off-gas from said processing vessel through a thermally insulated conduit to maintain the off-gas at an effective temperature to substantially prevent the formation of complex organic compounds;
• removing said molten material from said processing chamber;
• monitoring the amount of carbon particulate entrained in the off-gas using a first monitor;
• injecting an oxidant into said processing chamber in an amount effective to convert a majority of said carbon particulate to carbon monoxide;
• rapidly cooling the off-gas from said effective temperature to a temperature of less than about 150.degree. C.;
• separating the particulate from the cooled off-gas so as to form a product gas comprised of from about 45% to about 55% of hydrogen and from about 30% to about 40% of carbon monoxide;
• and
• monitoring the composition of the product gas using a second gas monitor.

An apparatus for treating toxic and hazardous medical waste consisting of inorganic and organic components, comprising:

• a waste processing chamber;
• a first collection means for receiving a charge of waste, first sealing means for closing said first collection means to the surrounding environment so as to isolate the charge of waste therein, a second collection means for receiving waste from said first collection means, second sealing means for closing said second collection means to said first collection means and the surrounding environment so as to isolate a charge of waste received therein;
• conveyor means for continually feeding waste to said processing chamber at a controlled feed rate;
• means for applying a vacuum pressure within said processing chamber;
• means for venting said second collection means to said processing chamber;
• a plasma arc torch mounted within said processing chamber for heating said waste to convert organic components of the waste to a gas comprising hydrogen, carbon monoxide and carbon dioxide, and to particulate including carbon particulate, and to convert inorganic components of the waste substantially to molten material, the gas exiting said processing vessel as an off-gas;
• thermally insulated conduit means for maintaining the off-gas at an effective temperature to substantially prevent the formation of complex organic compounds;
• an oxidant supply system for injecting an oxidant into said processing chamber in an amount effective to convert a majority of said carbon particulate to carbon monoxide;
• a control system for controlling the amount of oxidant injected into said processing chamber so as to minimize the formation of carbon particulate;
• and
• cooling means for rapidly cooling the off-gas from said effective temperature to a temperature of less than about 150.degree. C. and for separating the particulate from the cooled off-gas to form a product gas.

A method for treating waste consisting of organic and inorganic components, comprising the steps of:

• feeding waste into a first collection means and closing said first collection means to the surrounding environment, discharging the waste from said first collection means to a second collection means, and closing said second collection means to said first collection means and the surrounding environment;
• conveying the waste at a controlled rate into a processing chamber;
• heating said processing chamber using a plasma arc torch to a temperature effective to convert organic components of the waste to a gas comprising hydrogen, carbon monoxide and carbon dioxide, and particulate including carbon particulate, and to convert inorganic components of the waste substantially to molten material;
• maintaining the processing chamber under vacuum to withdraw the gas exiting said processing vessel as an off-gas;
• passing the off-gas from the processing chamber through a thermally insulated conduit to maintain the off-gas at an effective temperature to substantially prevent the formation of complex organic compounds;
• removing said molten material from said processing chamber, and cooling the removed molten material to form a non-leachable solid material;
• monitoring the amount of carbon particulate entrained in the off-gas;
• injecting an oxidant into said processing chamber in an amount effective to convert a majority of said carbon particulate to carbon monoxide and to minimize the formation of carbon particulate;
• rapidly cooling the off-gas from said effective temperature to a temperature of less than about 150.degree. C.;
• and
• neutralizing acidic gases in the cooled off-gas to form a product gas.