Process for the non-incineration decontamination of materials containing hazardous agents

Information

  • Patent Grant
  • 6462249
  • Patent Number
    6,462,249
  • Date Filed
    Monday, February 12, 2001
    23 years ago
  • Date Issued
    Tuesday, October 8, 2002
    21 years ago
Abstract
A process for the low temperature, non-incineration decontamination of contaminated materials, such as chemical weapon components containing residual quantities of chemical warfare agents. The process includes the steps of (a) contacting the contaminated materials with steam at substantially ambient pressure in a substantially dry first heated vessel for a period of at least about 15 minutes, the steam being at a temperature of at least about 560° C., (b) removing condensible and non-condensible gases from the first heated vessel and heating them in a second vessel at substantially ambient pressures to temperatures of at least about 500° C. for a period of at least about one second in an atmosphere containing steam in a concentration greater than about 250% of stoichiometry, and (c) catalytically treating non-condensible gases from the second vessel in the presence of oxygen so as to reduce the concentration of chemical warfare agents to less than about 1.0 mg/m3 at standard temperature and pressure.
Description




FIELD OF THE INVENTION




This invention relates generally to processes for decontaminating contaminated materials, such as chemical weapon components, and, more specifically, to processes for decontaminating contaminated materials without using incineration methods.




BACKGROUND OF THE INVENTION




The decontaminating of contaminated material can be very difficult. This is especially the case with respect to the decommissioning of chemical weapons carrying chemical warfare agents. The principal problem in this regard is how to safely remove, neutralize and dispose of the extremely toxic chemical warfare agents used in such chemical weapons. Modern technology has become increasingly successful in the neutralization of these chemical warfare agents—once the agents have been removed from the chemical weapon housing. However, after the bulk of the chemical warfare agents have been removed from the chemical weapons housings, the housings and their various components typically remain contaminated with residual amounts of the chemical warfare agents. The decontamination of these chemical weapon components remains a difficult problem.




Most prior art methods for decontaminating chemical weapon components have employed a two-step process. In a first step, the components are subjected to liquid chemicals or to high temperatures to remove and decompose essentially all of the chemical warfare agents adhering to the chemical weapon components. In a second step, residual vapors from the first step are incinerated to eliminate any and all residual chemical warfare agents in those vapors.




The incineration step has now been questioned, however, as possibly allowing potentially toxic combustion products to be released to the atmosphere. Accordingly, the incineration step has been banned in many industrial countries, including in the United States.




Thus, there is a need for a new method of decontaminating chemical weapon components which completely eliminates all traces of chemical warfare agents in an efficient and inexpensive manner, and without the use of an incineration step.




SUMMARY




The invention satisfies this need. The invention is a process for the low temperature, non-incineration decontamination of contaminated materials containing hazardous agents, the process comprising (a) contacting the contaminated materials and the hazardous agents with steam at substantially ambient pressure in a substantially dry first heated vessel for a period of at least about 15 minutes, the steam being at a temperature of at least about 560° C., whereby essentially all of the hazardous agents are removed from the contaminated materials, (b) removing a first gaseous discharge stream containing hazardous agents from the first heated vessel, the first gaseous discharge stream comprising a condensible moiety and a non-condensible moiety, (c) heating the first gaseous discharge stream at substantially ambient pressure in a substantially dry second vessel to at least about 500° C. and maintaining the first gaseous discharge stream in the second vessel of at least about 500° C. for a period of at least about one second in an atmosphere containing steam in a concentration greater than about 150% of stoichiometry, whereby at least about 99 weight percent of the hazardous agents within the first gaseous discharge stream are converted to non-hazardous agents, (d) removing a second gaseous discharge stream containing a reduced concentration of hazardous agents from the second vessel, the second gaseous discharge stream comprising a condensible moiety and a non-condensible moiety, (e) having a concentration of hazardous agents less than about 100 mg/l, (f) increasing the pH of the condensate to at least about 8.0 so as to reduce the concentration of hazardous agents within the condensate to less than about 1.0 mg/l, and (g) catalytically treating the non-condensible moiety of the second gaseous discharge stream in the presence of oxygen so that the concentration of hazardous agents within the non-condensible moiety of the second gaseous discharge stream is reduced to less than about 1.0 mg/m


3


at standard temperature and pressure.




The process is especially applicable where the contaminated materials are chemical weapon components and the hazardous agents are chemical warfare agents.











DRAWINGS




These features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying figures where:





FIG. 1

is a process flow diagram illustrating the process of the invention;





FIG. 2

is a diagrammatic cross-sectional side view of flushing apparatus useable in the invention;





FIG. 3

is a diagrammatic cross-sectional side view of a heated vessel useful in the invention;





FIG. 4A

is a diagrammatic cross-sectional side view of a second heated vessel useful in the invention;





FIG. 4B

is a cross-sectional view of the heated vessel illustrated in

FIG. 4A

, taken along line


4


B—


4


B;





FIG. 5

is a diagrammatic cross-sectional side view of a third heated vessel useful in the invention; and





FIG. 6

is a detailed perspective view of an auger useful in the invention.











DETAILED DESCRIPTION




The following discussion describes in detail one embodiment of the invention and several variations of that embodiment. This discussion should not be construed, however, as limiting the invention to those particular embodiments. Practitioners skilled in the art will recognize numerous other embodiments as well.




The invention is a process for the low temperature, non-incineration decontamination of contaminated materials containing hazardous agents. By “hazardous agents,” it is meant any chemical compound or material which is considered harmful to humans and/or other life forms. Hazardous agents are typically organic in nature, but can also be toxic metals or metal compounds which are volatilized at temperatures between 560° C. and 500° C. Such metals include mercury and lead.




The invention is especially applicable to the decontamination of chemical weapon components, wherein the hazardous agents are chemical warfare agents. By the term “chemical warfare agents,” it is meant any chemical which, through its chemical action on life processes, can cause death, temporary incapacitation or permanent harm to humans or animals.




In the process, as illustrated in

FIG. 1

, the chemical weapon components


10


, such as missile warheads or bombs, are opened and the chemical warfare agents contained therein are flushed out. That portion of the chemical warfare agents flushed out of the chemical weapon components


10


are then removed to a separate treating facility (not shown) for pacification.




After being flushed out, the chemical weapon components


10


continue to be contaminated with residual amounts of the chemical warfare agents. These flushed out, but still contaminated, chemical weapon components


10


are next sealed within a substantially dry first heated vessel


12


. Within the first heated vessel


12


, the chemical warfare agents are contacted with steam at a substantially ambient pressure for a period of at least about 15 minutes, typically for a period of between about 15 minutes and about 4 hours, most typically for a period between about 15 minutes and about 2 hours. By “substantially ambient pressure,” it is meant at a pressure between about 14.5 psia and about 14.7 psia. The temperature of the steam in contact with the chemical warfare agents within the first heated vessel


12


is at least about 560° C., and is typically between about 560° C. and about 750° C. By this contacting step, essentially all of the chemical warfare agents within, and adhering to, the chemical weapon components


10


are removed from the chemical weapon components


10


and transferred into a gaseous steam-containing phase.




The gaseous, steam-containing phase containing the chemical warfare agents in the first heated vessel


12


is removed from the first heated vessel


12


via a first discharge line


16


as a first gaseous discharge stream. This first gaseous discharge stream comprises a condensible moiety and a non-condensible moiety.




After removal from the first heated vessel


12


, the first gaseous discharge stream is heated in a substantially dry second vessel


18


at substantially ambient pressure to at least about 500° C. (typically between about 500° C. and about 700° C.). Within the second vessel


18


, the first gaseous discharge stream is maintained at a temperature of at least about 500° C. for a period of at least about one second in an atmosphere containing steam at a concentration between about 150% and about 350% of stoichiometry, preferably between about 250% and about 300% of stoichiometry, and most preferably between about 225% and about 275% of stoichiometry. Typically, the first gaseous discharge stream is thus maintained within the second vessel for a period of between about 1 and 10 seconds, most typically between about 1 and about 5 seconds. The term “stoichiometry” in this sense is meant to indicate the quantity of steam theoretically capable of reacting all of the chemical warfare agents within the first gaseous discharge stream to non-chemical warfare agents. By this step, at least about 99 wt. %, typically at least about 99.9 wt. % and, most typically, at least about 99.99 wt. %, of the chemical warfare agents within the first gaseous discharge stream are converted to non-chemical warfare agents.




The gaseous mixture within the second vessel


18


is removed from the second vessel


18


via a second gaseous discharge line


20


as a second gaseous discharge stream. This second gaseous discharge stream also comprises a condensible moiety and a non-condensible moiety. The second gaseous discharge stream is passed through a condenser


22


, wherein the condensible moiety of the second gaseous discharge stream is condensed to condensate. In a typical embodiment of the invention, the concentration of chemical warfare agents within this condensate is less than about 100 mg/l.




The pH of the condensate is then increased to at least about 8.0 (typically in a condensate treating vessel


24


), so as to reduce the concentration of chemical warfare agents within the condensate to less than about 1.0 mg/l.




The non-condensible moiety of the second discharge gaseous stream is removed from the condenser


22


via an overhead line


26


to a reactor


28


where it is catalytically treated in the presence of oxygen so as to reduce the concentration of chemical warfare agents within the non-condensible moiety to less than about 1.0 mg/m


3


(at standard pressure and temperature). This catalytic treatment step can be carried out in one of a large number of catalytic oxidation processes known in the art, such as the Thermatrix Blameless Oxidation process licensed by Thermatrix, Inc. of California, Edge II™ licensed by Alzeta Corporation of California and Econ-Abator Catalytic Oxidation Systems licensed by Huntington Environmental Systems of Illinois. The CATOX Process licensed by Honeywell, Inc. of Morristown, N.J. has been found to be particularly effective in the oxidation of chemical warfare agents within the non-condensible moiety of the second discharge stream to non-chemical warfare agents. This process is disclosed in detail in U.S. Pat. No. 6,080,906, the entirety of which is incorporated herein by this reference.




As illustrated in

FIG. 2

, the chemical weapon components


10


can be flushed out using a flushing apparatus


30


comprising a primary flushing vessel


32


and a secondary flushing vessel


34


. In the primary flushing vessel


32


, the chemical weapon components


10


are initially opened and the mobile chemical warfare agents contained therein are dumped into the bottom of the primary flushing vessel


32


for removal to the separate treating facility


36


. After substantially all of the mobile chemical warfare agents have gravitated out of each chemical weapon component


10


, the chemical weapon component


10


is. placed into the secondary flushing vessel


34


.




The secondary flushing vessel


34


contains a rotating carousel


38


which is partially submerged within a quantity of liquid flushing agent


40


, such as water or other solvent. The carousel


38


rotates individual chemical weapon components


10


into and out of the flushing agent. Both above and below the liquid level


42


, high pressure sprayers


44


are capable of spraying liquid flushing agent into the open ends


46


of the chemical weapon components


10


to flush out additional amounts of chemical warfare agents.




Preferably, the carousel


38


is adapted to retain each chemical weapon component


10


at an angle of between about 30° and about 90° with respect to the horizontal so that the open end


46


of each chemical warfare component


10


is canted downwardly when the chemical weapon component


10


is disposed at the top of the carousel


38


and is canted upwardly when rotated to the bottom of the carousel


38


. By this design, the chemical weapon components


10


within the carousel


38


automatically drain when rotated to the top of the carousel


38


and automatically draw liquid into each chemical weapon component


10


when rotated to the bottom of the carousel


38


.




After exiting the secondary flushing vessel


34


, the chemical weapon components


10


are placed into the first heated vessel


12


where they are contacted with steam as described above. As illustrated in the drawings, the first heated vessel


12


can be equipped with electrical heating coils


47


so that the first heated vessel


12


can be heated electrically, preferably by induction heating.




Operation of the first heated vessel


12


can be carried out in a batch-wise mode or can be carried out in a semi-batch, semi-automatic or fully automatic modes.

FIG. 3

illustrates the operation of the first heated vessel


12


in a semi-batch mode. As illustrated in

FIG. 3

, the first heated vessel


12


houses a pair of discrete bundles


48


of chemical weapon components


10


. Typically, each bundle


48


is a palletized plurality of chemical weapon components


10


. Each bundle


48


is subjected to two separate applications of heated steam. After each application, the forward-most bundle


48




a


is removed from the outlet end


50


of the first heated vessel


12


, the rearward-most bundle


48




b


is moved forward within the first heated vessel


12


and a new bundle


48




c


is disposed within the first heated vessel


12


at the inlet end


52


of the first heated vessel


12


.




In another embodiment (not shown), chemical weapon components


10


are loaded onto one or more trays which are pushed through the first heated vessel


12


in a similar fashion as the bundles


48


described immediately above.





FIGS. 4A and 4B

illustrate a semi-automatic embodiment. In this embodiment, a plurality of elongate racks


54


are disposed within the first heated vessel


12


. Each rack


54


is adapted to accept, end-to-end, a plurality of individual chemical weapon components


10


. A charging mechanism (not shown) is disposed at the inlet end


52


of the first heated vessel to charge one chemical weapon component


10


at a time into the inlet end


56


of one of the racks


54


. As one chemical weapon component


10


is charged into the inlet end


56


of a rack


54


, a fully decontaminated chemical weapon component


10


is removed at the outlet end


58


of that rack


54


by a discharging mechanism (not shown). Either the charging and discharging mechanisms or the racks


54


rotate about the longitudinal axis


59


of the first heated vessel


12


so that the charging mechanism loads a chemical weapon component


10


into each of the racks


54


in repeated, serial fashion. By this operation, all of the racks


54


are serially loaded and unloaded.





FIG. 5

illustrates yet another embodiment of the invention. This embodiment of the invention can be operated in either a semi-automatic or full automatic configuration. In this embodiment, an auger


60


is disposed within the first heated vessel


12


. Its configuration is suitable for chemical weapon components


10


of relatively reduced size, such as pre-shredded chemical weapon components


10


. In this embodiment, as the auger


60


slowly rotates, chemical weapon components


10


are slowly moved from the inlet end


52


of the first heated vessel


12


towards the outlet end


50


of the first heated vessel


12


.




In many cases, operation of this embodiment is facilitated by loading the chemical weapon components


10


within the first heated vessel


12


with a filler material, such as crushed limestone, aluminum silicate or granulated charcoal. Typically, the filler material is comprised of clumps having a width between about ¼ inch and about 1 inch, typically between about ¼ inch and about ½ inch. In a typical operation, such filler material comprises between about one third and about two thirds of the volume of loose material within the first heated vessel


12


. The filler material is removed at the outlet end


50


of the first heated vessel


12


with the fully decontaminated chemical weapon components. The filler material is then separated from the chemical weapon components


10


, such as by screening or air blasting. Thereafter, the filler material can be recycled for repeated uses within the process.





FIG. 6

illustrates in detail an auger configuration useful in this embodiment. In this configuration, the auger


60


is composed of an axially rotating central member


62


to which is attached a plurality of outwardly radiating support members


64


. The support members


64


are disposed in a spiral about the central member


62


. At the distal end of each support member


62


is an auger blade


66


. In the embodiment illustrated in

FIG. 6

, each auger blade


66


is L-shaped, having a lateral component


68


and a vertical component


70


. The auger blades


66


are attached to the support elements


64


in an adjustable fashion, such as by being attached with a bolt and nut


72


. By being adjustable, the angle of the individual auger blades


66


can be optimally adjusted to smoothly move loose material through the first heated vessel


12


.




For many materials, it has been found that varying the angle of the auger blades


66


along the length of the auger


60


can be beneficial. In some operations, it can actually be beneficial to angle some of the auger blades


66


to nudge material backwards within the first heated vessel


12


while the remainder of the auger blades


66


are angled to push the material forward. Such a configuration has been found to be advantageous in maintaining the smooth flow of certain materials through the first heated vessel


12


.




The invention has been found to provide an extremely effective method for decontaminating chemical weapon components without having to resort to incineration steps. Because the process is carried out at substantially ambient pressures, capital, operating and maintenance costs are reduced to a minimum. The invention can also provide an effective method for minimizing the overall quantity of a “mixed” waste containing organic contaminants and radioactive contaminants. The non-radioactive portion of any such mixed waste can be substantially eliminated by use of the invention, thus minimizing the overall quantity of waste which must be disposed of. The invention has also been further found to provide an effective method for decontaminating other contaminated materials containing hazardous agents, such as contaminated soils.




Having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.



Claims
  • 1. A process for the low temperature, non-incineration decontamination of contaminated materials containing hazardous agents, the process comprising:(a) contacting the contaminated materials and the hazardous agents with steam at substantially ambient pressure in a substantially dry first heated vessel for a period of at least about 15 minutes, the steam being at a temperature of at least about 560° C., whereby essentially all of the hazardous agents are removed from the contaminated materials; (b) removing a first gaseous discharge stream containing hazardous agents from the first heated vessel, the first gaseous discharge stream comprising a condensible moiety and a non-condensible moiety; (c) heating the first gaseous discharge stream at substantially ambient pressure in a substantially dry second vessel to at least about 500° C. and maintaining the first gaseous discharge stream in the second vessel of at least about 500° C. for a period of at least about one second in an atmosphere containing sufficient steam so that at least about 99 weight percent of the hazardous agents within the first gaseous discharge stream are converted to non-hazardous agents; (d) removing a second gaseous discharge stream containing a reduced concentration of hazardous agents from the second vessel, the second gaseous discharge stream comprising a condensible moiety and a non-condensible moiety; (e) passing the second gaseous discharge stream through a condenser wherein the condensible moiety of the second gaseous discharge stream is condensed to condensate having a concentration of hazardous agents less than about 100 mg/l; (f) increasing the pH of the condensate to at least about 8.0 so as to reduce the concentration of hazardous agents within the condensate to less than about 1.0 mg/l; and (g) catalytically treating the non-condensible moiety of the second gaseous discharge stream in the presence of oxygen so that the concentration of hazardous agents within the non-condensible moiety of the second gaseous discharge stream is reduced to less than about 1.0 mg/m3 at standard temperature and pressure.
  • 2. The process of claim 1 wherein the contacting of the contaminated materials and hazardous agents with steam in step (a) is carried out using steam at a temperature between about 560° C. and about 750° C.
  • 3. The process of claim 1 wherein the contacting of the contaminated materials and hazardous agents with steam in step (a) is carried out for a period of between about 15 minutes and about 4 hours.
  • 4. The process of claim 1 wherein the contacting of the contaminated materials and hazardous agents with steam in step (a) is carried out for a period of between about 15 minutes and about 120 minutes.
  • 5. The process of claim 1 wherein the maintaining of the first gaseous discharge stream at a temperature greater than about 500° C. in step (c) is carried out at a temperature between about 500° C. and about 700° C.
  • 6. The process of claim 1 wherein the maintaining of the first gaseous discharge stream at a temperature of at least about 500° C. in step (c) is carried out for a period between about 1 second and about 10 seconds.
  • 7. The process of claim 1 wherein the maintaining of the first gaseous discharge stream at a temperature of at least about 500° C. in step (c) is carried out for a period between about 1 second and about 5 seconds.
  • 8. The process of claim 1 wherein the heating and maintaining of the first gaseous discharge stream at a temperature of at least about 500° C. in step (c) converts at least about 99.99% of the hazardous agents within the first gaseous discharge stream to non-chemical warfare agents.
  • 9. A process for the low temperature, non-incineration decontamination of chemical weapon components containing chemical warfare agents, the process comprising:(a) contacting the chemical weapon components and the chemical warfare agents with steam at substantially ambient pressure in a substantially dry first heated vessel for a period of at least about 15 minutes, the steam being at a temperature of at least about 560° C., whereby essentially all of the chemical warfare agents are removed from the chemical weapon components; (b) removing a first gaseous discharge stream containing chemical warfare agents from the first heated vessel, the first gaseous discharge stream comprising a condensible moiety and a non-condensible moiety; (c) heating the first gaseous discharge stream at substantially ambient pressure in a substantially dry second vessel to at least about 500° C. and maintaining the first gaseous discharge stream in the second vessel of at least about 500° C. for a period of at least about one second in an atmosphere containing sufficient steam so that at least about 99 weight percent of the chemical warfare agents within the first gaseous discharge stream are converted to non-chemical warfare agents; (d) removing a second gaseous discharge stream containing a reduced concentration of chemical warfare agents from the second vessel, the second gaseous discharge stream comprising a condensible moiety and a non-condensible moiety; (e) passing the second gaseous discharge stream through a condenser wherein the condensible moiety of the second gaseous discharge stream is condensed to condensate having a concentration of chemical warfare agents less than about 100 mg/l; (f) increasing the pH of the condensate to at least about 8.0 so as to reduce the concentration of chemical warfare agents within the condensate to less than about 1.0 mg/l; and (g) catalytically treating the non-condensible moiety of the second gaseous discharge stream in the presence of oxygen so that the concentration of chemical warfare agents within the non-condensible moiety of the second gaseous discharge stream is reduced to less than about 1.0 mg/m3 at standard temperature and pressure.
  • 10. The process of claim 9 wherein the contacting of the chemical weapon components and chemical warfare agents with steam in step (a) is carried out using steam at a temperature between about 560° C. and about 750° C.
  • 11. The process of claim 9 wherein the contacting of the chemical weapon components and chemical warfare agents with steam in step (a) is carried out for a period of between about 15 minutes and about 4 hours.
  • 12. The process of claim 9 wherein the contacting of the chemical weapon components and chemical warfare agents with steam in step (a) is carried out for a period of between about 15 minutes and about 120 minutes.
  • 13. The process of claim 9 wherein the maintaining of the first gaseous discharge stream at a temperature greater than about 500° C. in step (c) is carried out at a temperature between about 500° C. and about 700° C.
  • 14. The process of claim 9 wherein the maintaining of the first gaseous discharge stream at a temperature of at least about 500° C. in step (c) is carried out for a period between about 1 second and about 10 seconds.
  • 15. The process of claim 9 wherein the maintaining of the first gaseous discharge stream at a temperature of at least about 500° C. in step (c) is carried out for a period between about 1 second and about 5 seconds.
  • 16. (Amended) The process of claim 9 wherein the heating and maintaining of the first gaseous discharge stream at a temperature of at least about 500° C. in step (c) converts at least about 99.99% of the hazardous agents within the first gaseous discharge stream to non-chemical warfare agents.
  • 17. The process of claim 9 wherein, prior to the contacting of the chemical weapon components and the chemical warfare agents with steam in step (a), the chemical weapon components are flushed with a liquid flushing agent in a flushing vessel, the flushing vessel comprising a liquid level of flushing agent and an internally disposed carousel for rotating a plurality of chemical weapon components into and out of flushing agent.
  • 18. The process of claim 9 wherein, prior to the contacting of the chemical weapon components and the chemical warfare agents with steam in step (a), the chemical weapon components are sprayed with liquid flushing agent from a plurality of spray nozzles.
  • 19. The process of claim 9 wherein, prior to the contacting of the chemical weapon components and the chemical warfare agents with steam in step (a), the chemical weapon components are sprayed with liquid flushing agent from a plurality of spray nozzles within a flushing vessel, the spraying of the chemical weapon components being carried out while a liquid level is maintained within the flushing vessel, the spraying of the chemical weapon components being accomplished by at least one spray nozzle disposed above the liquid level and by at least one spray nozzle disposed below the liquid level.
  • 20. The process of claim 9 wherein, during the contacting of chemical weapon components and chemical warfare agents with steam in step (a), the first vessel contains a plurality of discrete chemical weapon component bundles, each bundle containing a plurality of chemical weapon components.
  • 21. The process of claim 20 wherein each chemical weapon component bundle is contacted in step (a) with steam of at least about 560° C. for at least two different and distinct periods of at least about 15 minutes each.
  • 22. The process of claim 9 wherein, prior to the contacting of the chemical weapon components and the chemical warfare agents with steam in step (a), the chemical weapon components are disposed in a plurality of elongate racks within the first vessel, each elongate rack being sized and dimensioned to retain a plurality of chemical weapon components.
  • 23. The process of claim 9 wherein, prior to the contacting of the chemical weapon components and the chemical warfare agents with steam in step (a), the chemical weapon components are disposed in a plurality of elongate racks within the first vessel, each elongate rack being sized and dimensioned to retain a plurality of chemical weapon components, the first vessel having a longitudinal axis and the elongate racks being rotatable about the longitudinal axis.
  • 24. The process of claim 9 wherein the contacting of chemical weapon components and chemical warfare agents with steam in step (a) is conducted while the chemical weapon components are moved by an auger from an inlet end of the first vessel to an outlet end of the first vessel.
  • 25. The process of claim 9 wherein the contacting of chemical weapon components and chemical warfare agents with steam in step (a) is conducted while the chemical weapon components are moved by an auger having adjustable blades from an inlet end of the first vessel to an outlet end of the first vessel.
  • 26. The process of claim 25 wherein, during the contacting of the chemical weapon components and chemical warfare agents with steam in step (a), a filler material is mixed with the chemical weapon components within the first vessel.
  • 27. A process for the low temperature, non-incineration decontamination of chemical weapon components containing chemical warfare agents, the process comprising:(a) contacting the chemical weapon components and the chemical warfare agents with steam at substantially ambient pressure in a substantially dry first heated vessel for a period of between about 15 minutes and about 120 minutes, the steam being at a temperature of between about 560° C. and about 750° C., whereby essentially all of the chemical warfare agents are removed from the chemical weapon components; (b) removing a first gaseous discharge stream containing chemical warfare agents from the first heated vessel, the first gaseous discharge stream comprising a condensible moiety and a non-condensible moiety; (c) heating the first gaseous discharge stream at substantially ambient pressure in a substantially dry second vessel to at least about 500° C. and maintaining the first gaseous discharge stream in the second vessel at a temperature between about 500° C. and about 700° C. for a period of between about 1 second and about 5 seconds in an atmosphere containing sufficient steam so that at least about 99.99 wt. % of the chemical warfare agents within the first gaseous discharge stream are converted to non-chemical warfare agents; (d) removing a second gaseous discharge stream containing a reduced concentration of chemical warfare agents from the second vessel, the second gaseous discharge stream comprising a condensible moiety and a non-condensible moiety; (e) passing the second gaseous discharge stream through a condenser wherein the condensible moiety of the second gaseous discharge stream is condensed to condensate having a concentration of chemical warfare agents less than about 100 mg/l; (f) increasing the pH of the condensate to at least about 8.0 so as to reduce the concentration of chemical warfare agents within the condensate to less than about 1.0 mg/l; and (g) catalytically treating the non-condensible moiety of the second gaseous discharge stream in the presence of oxygen so that the concentration of chemical warfare agents within the non-condensible moiety of the second gaseous discharge stream is reduced to less than about 1.0 mg/m3 at standard temperature and pressure.
  • 28. The process of claim 27 wherein the first vessel is an electrically heated vessel.
  • 29. The process of claim 28 wherein the first vessel is heated by electrical induction.
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