Claims
- 1. A countercurrent, direct fired rotary kiln for the decontamination for a variety of materials containing hazardous organic materials comprising an elongated open ended cylindrical shell having an infeed end and a discharge end, means for supporting said shell for rotation about its longitudinal axis, a non-rotary closure for each end of said shell, means for feeding material to be treated into one end of said shell through its associated closure, means for discharging treated material from the other end of said shell through its associated closure, a burner in the interior of said shell, an elongated support means for said burner extending through the discharge end of said shell, said support means being reciprocatable independently of and relative to said shell and to said discharge end closure to position said burner at selectable distances from said discharge end to define a first material treatment zone having a length dimension extending between said burner and said infeed end and a second material treatment zone having a length dimension extending between said burner and said discharge end, means associated with said support means for selectively supplying fuel and combustion air to said burner means such that the combination of burner combustion, burner position within the kiln, and the nature of the infeed material results in selective establishment or relatively different material treatment environments within said first and second material treatment zones and selectable residence times of said material in said zones, an off-gas conduit extending through the feed end closure of said shell, and seal means to minimize air flow between the atmosphere and the interior of said shell.
- 2. The kiln of claim 1 wherein said support means is mounted on a carriage, said carriage being located outside of the discharge end closure and being mounted for reciprocation to move said burner to a selectable position within the interior of said shell spaced from the discharge end of said shell when said discharge end is closed.
- 3. The kiln of claims 1 or 2 including means supplying auxiliary air into said shell adjacent its discharge end.
- 4. The rotary kiln of claim 1 wherein said burner support means is sufficiently long so that it can be extended into the kiln shell to a distance of about 25% of the length of said shell, thereby supporting said burner for reciprocation over a distance within the kiln shell equal to about 25% of the length of said shell.
- 5. The kiln of claim 2 wherein the off-gas conduit is provided with an enlarged, flared inlet section positioned inside said shell and said material feed means discharges material into said shell behind said flared inlet.
- 6. The kiln of claim 2 wherein said material feed means includes means for feeding solids, slurries, and liquids.
- 7. The kiln of claim 2 wherein said material feed means includes a feed conduit which extends through the walls of said off-gas conduit to discharge material into said shell under said off-gas conduit.
- 8. In a direct fired, countercurrent, rotary kiln for the decontamination of materials containing hazardous organic materials, including an elongated open ended cylindrical shell, a non-rotary closure for each end of said shell, means for supporting said shell for rotation about its longitudinal axis whereby material fed into one end of said shell progresses toward the opposite end thereof, means for feeding material to be treated into one end of said shell, means for discharging non-volatilized treated material from the other end of said shell, the improvement comprising
- means defining a first environment zone of a first length extending interiorly of said kiln along the longitudinal dimension thereof from that end of said shell into which there is fed the organic-contaminated material to be treated, and
- means defining a second environmental zone of a second length extending interiorly of said kiln along the longitudinal dimension thereof from that end of said shell from which treated material is discharged, said first and second zones being different as respects their effect upon the material being treated and defining preselected residence times for said material within respective ones of such zones such that more highly volatile organic materials present in said contaminated materials are volatilized in said first zone and less highly volatile organic materials present in said contaminated materials are volatilized in said second zone,
- said zones being substantially colinearly and tandemly aligned with respect to one another such that the material being treated moves from said first zone into said second zone, thence to said means for discharging said non-volatile material,
- means for discharging volatilized organics from said kiln at that end of said kiln into which the organic-contaminated material is fed,
- said means defining said first zone and said means defining said second zone including a burner disposed within said shell intermediate said zones and defining one limit of each zone,
- means mounting said burner for reciprocatable movement along the longitudinal dimension of said shell independent of said end closures, and
- means for introducing a combustible gas mixture of slightly excess stoichiometric composition to said burner such that the environment of at least said first zones is substantially reductive.
- 9. The improvement of claim 8 and including seal means associated with said non-rotary end closures such that the only substantial flow of gaseous material from said shell comprises volatilized matter originating from the infeed materials and combustion products originating from said burner.
- 10. The improvement of claim 9 wherein said means mounting said burner provides for positioning of said burner a maximum distance of about 25% of the length dimension of said shell from that end of closure from which non-volatilized treated material is discharged.
- 11. The improvement of claim 8 and including means for introducing a source of oxygen to the interior of said kiln in the vicinity of that end closure from which non-volatilized treated material is discharged.
Parent Case Info
This is a continuation of application Ser. No. 07/125,379, filed Nov. 25, 1987, now abandoned, which was a division of application Ser. No. 06/869,200, filed May 29, 1986, now U.S. Pat. No. 4,746,290.
US Referenced Citations (22)
Foreign Referenced Citations (1)
Number |
Date |
Country |
423065 |
Oct 1966 |
CHX |
Divisions (1)
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Number |
Date |
Country |
Parent |
869200 |
May 1986 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
125379 |
Nov 1987 |
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