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US 2004/0105800 A1Published application
Device and method for removal of harmful substance
OwnerKoichi Kawaseinventor
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OwnerKoichi Kawaseinventor
Estimating the term…
There are provided a harmful substance removing method and apparatus wherein a workpiece containing harmful substances is heated within a crucible (30) in an unopened, hermetically sealed state of the crucible in the absence of oxygen, at a low pressure and a higher temperature, and which can improve the treatment efficiency, does not release carbon dioxide, can reduce the apparatus size and the manufacturing cost, and performs heat treatment at a relatively low temperature to reduce the running cost. A cooling vessel (82) and gas liquefying traps (86c, 86b, 86a) and traps (94a, 94b, 94c) are provided between the crucible (30) and suction force generating vacuum pumps (90, 98), and the space between the crucible (30) and the vacuum pumps (90, 98) is kept in a hermetically sealed state. A screw (50) for introducing and discharging the workpiece into and from the crucible (30) is provided. The workpiece is fed to the screw (50) from an upward introducing member (58) which is shut off from the exterior in a hermetically sealed state, and is discharged from the screw (50) through a downward discharge member (60) which is shut off from the exterior in a hermetically sealed state. With this construction, the workpiece can be decomposed without opening the crucible (30) and therefore it is possible to enhance the treatment efficiency.
(Amended) A method for removing harmful substances, which method comprises connecting a crucible for placing therein a workpiece containing harmful substances and a suction means with each other in a hermetically sealed state, heating said crucible by a heating means to gasify the harmful substances in the interior of the crucible, introducing nitrogen into said crucible, and sucking the nitrogen and the gasified harmful substances to the exterior from said crucible by said suction means.
(Deleted)
(Amended) A harmful substance removing apparatus comprising a crucible for accommodating a workpiece containing harmful substances, a heating means for heating the interior of said crucible and gasifying the harmful substances contained in the workpiece, a nitrogen introducing means for introducing nitrogen into said crucible, a suction means for generating a suction force, a cooling device for liquefying and collecting the gasified harmful substances, said cooling device being disposed between said suction means and said crucible, a conveyance means communicating with the interior of said crucible to load and unload the workpiece into and from the crucible, an upward introducing member for introducing the workpiece into said conveyance means in a state capable of being shut off from the exterior in a hermetically sealed manner, and a downward discharge member for discharging the workpiece from said conveyance means in a state capable of being shut off from the exterior in a hermetically sealed manner, wherein said crucible, said cooling device, and said suction means are connected together in a closed state, and the suction force of said suction means is exerted on the interior of said crucible through said cooling device.
(Deleted)
Dependencies are inferred from the claim text.