Tool decontamination apparatus

• US 4,630,625 A
• Filed: 04/29/1983
• Issued: 12/23/1986
• Est. Priority Date: 01/22/1981
• Status: Expired due to Fees

• Current Assignee: Quadrex HPS Incorporated
• Original Assignee: Quadrex HPS Incorporated
• Inventors: Fowler, David E., Capella, Joseph A.
• Primary Examiner(s): Marcus, Stephen
• Application Number:
  US06/490,243
• Time in Patent Office: 1,334 Days
• Field of Search: 134/99, 134/104, 134/107-111, 134/135, 134/174, 134/175, 134/186, 134/199, 134/200, 134/102, 252/626, 252/630, 252/631
• US Class Current: 134/104.3
• CPC Class Codes: B05B 15/555 discharged by cleaning nozzles
• CPC Class Codes: B08B 3/02 Cleaning by the force of jets or sprays

Abstract

Disclosed is a system and method for cleaning radioactively contaminated articles, including tools and like items of hardware. The system includes a cleaning chamber for receiving and sealing therein the contaminated articles, a high pressure spray gun disposed within the cleaning chamber for spraying the contaminated articles with a clean solvent to dislodge and dissolve the contaminants, and a system for decontaminating the solvent for reuse. The cleaning chamber includes a drain having the capacity to remove contaminated solvent at a rate at least as great as that at which the solvent is sprayed into the chamber, such that substantially no contaminated solvent collects in the cleaning chamber.

Claims

1. System for cleaning radioactively contaminated articles, which comprises:

a cleaning chamber adapted to receive and seal therein the contaminated articles,

means for spraying the contaminated articles with a high pressure spray of a clean solvent to dislodge and/or dissolve the contaminants,

means for draining the contaminated solvent from the cleaning chamber at a rate at least as great as that which the clean solvent is sprayed into the cleaning chamber,

and means for decontaminating the contaminated solvent for reuse,

a cabinet having an opening through which the articles may be placed into and removed from the cleaning chamber,

means for closing and sealing the opening,

window means for providing a view of the inside of the cleaning chamber when the opening is closed and sealed,

and glove means for permitting the manipulation of the articles within the cleaning chamber when the opening is closed and sealed,

a solvent reservoir adapted to receive contaminated solvent drained from the cleaning chamber,

filter means for removing contaminants suspended in the contaminated solvent,

and means for recirculating solvent from said solvent reservoir through the filter means,

a low pressure high volume pump having an intake connected to the pick-up tube, a first conduit connecting the discharge of the low pressure high volume pump to the filter means, and a second conduit connecting the filter means to the solvent reservoir, and

a high pressure low volume pump having an intake connected to the second conduit,

a spray gun in the cleaning chamber,

and means for connecting the discharge from the high pressure low volume pump to the spray gun.

2. A system for cleaning contaminated articles which comprise:

a cleaning chamber having an opening through which contaminated articles are inserted,

means closing the chamber opening,

glove means integral with the chamber for manipulation of articles therein from without, when the chamber is closed,

means for spraying the articles with a spray of clean solvent so as to dislodge and/or dissolve contaminants thereon, the solvent spray producing a pressure surge within the cleaning chamber upon introduction thereto, and

means for reducing the pressure surge in the chamber so as to minimize potential escape of contamination through chamber openings to the environs outside thereof and for precluding overpressurization of said glove means, said means for reducing the pressure surge being only operative substantially contemporaneously at the time periods of the pressure surge, and,

filter means disposed downstream of said means for reducing pressure surge and for assisting in balancing underpressurization in the chamber while restraining escape of contamination therethrough to the environs.

3. The system of claim 2 wherein said means for reducing the pressure surge includes:

condenser means in communication with the chamber,

gas withdrawal means for conducting the gases across the condenser means in order to condense vapor component in the gases, and

vent means to atmosphere in communication with the condenser whereby noncondensed vapors extracted at time of the pressure surge are vented to atmosphere, thus resulting in a depressurization of the chamber to near atmosphere or below while allowing reversal of gas flow through said vent means when said pressure surge subsides.

4. The system as described in claim 3 including means for cleansing vapor liquified by the condenser for reuse in the chamber.

5. The system as described in claim 3 including additional filter means in the path of said vent means downstream of the condenser means for restraining passage of solvent vapor which may have particulate contaminants therein.

6. An apparatus for controlling escape of contamination from a cleaning chamber and for minimizing pressure surge therewithin comprising:

a cleaning chamber,

glove means integral with the chamber for manipulation of articles therein from without, when the chamber is closed,

a drain line coupled to the chamber for draining cleaning solvent therefrom;

a solvent line in communication with the chamber for introducing solvent thereto,

a recirculating circuit for the solvent in fluid communication with said drain and solvent lines,

means communicating with the chamber for minimizing over pressurization thereof by providing a substantially negative pressure therein upon solvent introduction while maintaining said chamber substantially at or below atmospheric so as to reduce escape of contaminated gases therefrom while simultaneously reducing structural working loads on the chamber structure and system, and

said last mentioned means including a vent means to atmosphere having a filter means therein communicating with the chamber interior whereby solvent vapor having contaminated vapor therein is cleansed at said filter prior to escape while allowing a return therethrough of ambient atmosphere, thus simultaneously reducing pressure on said glove means and pressure loads on the chamber structure.

7. The apparatus of claim 6, wherein the means for minimizing over pressurization of the chamber upon solvent introduction while maintaining the chamber at or below atmosphere further includes:

a condenser means coupled to the chamber for condensing those vapors not condensed at time of pressure surge in the chamber, said condenser means being disposed in said circuit upstream of said vent means thus resulting in a chamber under pressure that draws air back thereinto through said vent means subsequent to the surge occurring upon solvent introduction.

8. The apparatus of claim 6 wherein said apparatus for minimizing pressure surge within the chamber includes:

gas withdrawal means for extracting gases containing contaminated vapor from the chamber,

a condenser means upstream of the gas withdrawal means for condensing uncondensed vapor carried by the gases and,

said vent means to atmosphere being disposed downstream of said gas withdrawal means thus resulting in the chamber under pressure that draws air back thereinto through said vent means subsequent to the pressure surge occurring upon solvent introduction.

9. An apparatus for cleansing contaminated articles comprising:

a cleaning chamber adapted to receive and seal therewithin the contaminated articles, said chamber having a removable cover means so as to permit introduction of the articles thereinto prior to closing of the cover means and a glove means enabling manipulation from outside the chamber of articles therewithin,

means for spraying the contaminated articles with a solvent spray to dislodge and dissolve contaminants on the articles and wherein the solvent spray results in a pressure surge arising from the vapor spray therewithin,

means for inducing a negative pressure at time of such pressure surge and for maintaining said chamber at or below atmospheric pressure when such pressure surge occurs so as to minimize the escape of contaminated fluid to the immediate environs external of the chamber itself and to protect said glove means against over pressurization damage,

said means for inducing negative pressure at time of such pressure surge and maintaining the pressure within the chamber at or below atmospheric including a condenser means and a gas withdrawal fan means coupled to the chamber for drawing vapor therefrom across the condenser, and

a vent means in communication with said condenser means and gas withdrawal means and downstream thereof whereby non-condensed vapors are extracted at the time of vapor surge and vented to atmosphere while filtering contaminated vapor therefrom and resulting in a chamber having atmospheric pressure or below which draws air back through the vent, thus precluding overpressurization of the chamber and escape of contaminated gases to the immediate environs thereabout.