Hazardous waste treatment method and apparatus
AssigneesBenjamin Chun Pong Chan, Edmund Kin On Lau
InventorBenjamin Chun Pong Chan
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Abstract
An apparatus and method for treating the off-gas byproduct of a waste treatment system using a plasma torch. The off-gas of a graphite electrode plasma arc furnace includes carbon black or soot which must be removed. The plasma torch employs a carbon dioxide and oxygen mixture as a working gas to avoid the creation of nitrogen oxides and other toxic by-products. The plasma torch ionizes the working gas, resulting in the creation of carbon monoxide and reactive oxygen, which assists in eliminating carbon black/soot from the off-gas. Oxygen and steam are atomized and injected into the chamber housing the plasma torch system. A process control feedback system monitors the content of the output gas and controls the operation of the injectors and the plasma torch.
Claims29
A method for treating an off-gas from a waste treatment system, comprising the steps of:
- (a) receiving the off-gas at an input port of a refractory-lined cylindrical chamber;
- (b) heating said chamber by ionizing a working gas using a DC powered plasma torch proximate the input port within said chamber, said working gas including a mixture of carbon dioxide and oxygen and excluding nitrogen, thereby converting said off-gas to an output gas;
- and
- (c) outputting the output gas from said chamber.
An apparatus for treating an off-gas from a waste treatment system, comprising
- (a) a refractory-lined cylindrical chamber having an input port for receiving the off-gas and an output port;
- and
- (b) a DC powered plasma torch proximate the input port within said chamber, said torch receiving a working gas, said working gas including a mixture of carbon dioxide and oxygen and excluding nitrogen;
- wherein said plasma torch heats said chamber and the off-gas is thereby converted to an output gas, which is ejected through said output port.
A waste treatment system for treating hazardous waste, comprising:
- (a) a primary waste treatment stage, said primary waste treatment stage receiving the hazardous waste and producing a by-product off-gas;
- (b) a secondary waste treatment stage coupled to said primary waste treatment stage and receiving said off-gas, said secondary waste treatment stage including:
- (i) a refractory-lined cylindrical chamber having a input port for tangentially receiving said off-gas and an output port;
- and
- (ii) a DC powered plasma torch proximate the input port within said chamber, said torch receiving a working gas, said working gas including a mixture of carbon dioxide and oxygen and excluding nitrogen;
- wherein said plasma torch heats said chamber and said off-gas is thereby converted to an output gas, which is ejected through said output port.
Dependencies are inferred from the claim text.