Claims
- 1. A catalytic structure for removal of nitrogen oxides from combustion exhaust gas containing dust, said catalytic structure comprising:
- a plurality of plates, said plurality of plates being disposed to form a plurality of individual structures of plates which are disposed one from the other to form spaces thereinbetween for the exhaust gases to flow therethrough;
- at least a portion of said plates having openings therein;
- said openings in said plates being formed at least when said structures are assembled, such that said openings connect the spaces between at least one side of one of said structures of plates to another side of said one of said structures of plates;
- said plates comprising a catalytic ceramic material;
- said plates having surfaces exposing catalyst to said gas;
- said combustion exhaust gas having a known dust content entrained therein; and
- said catalytic material being formulated from components selected with regard to said known dust content of said exhaust gas, to provide said catalytic material with a wear characteristic to abrasion by said dust entrained in said exhaust gas thereby reactivating said catalytic action of said catalytic ceramic material, by wearing away at said surfaces of said plates being fouled in use, at a rate related to said wear characteristic of said catlytic ceramic material and said dust content of said exhaust gas, whereby said abrasion of said surfaces of said plates proceeds at a given rate in use, sufficient to abrade away a substantial portion of said surfaces fouled in use, whereby fresh catalyst surface is continuously exposed to said exhaust gas, and further whereby material abraded from said surfaces of said plates of said catalytic ceramic material is at least partially carried away by said exhaust gas.
- 2. The structure according to claim 1 wherein said plates have a given thickness and wherein said spaces between said structures of plates are approximately 2 to approximately 4.5 times said plate thickness.
- 3. The structure according to claim 1 wherein said plates have plinths which engage with neighboring plates, and at least some of said plates have recesses between the plinths, which together with an edge of a neighboring plate forms said openings between said spaces.
- 4. The structure according to claim 2 wherein said plates have plinths which engage with neighboring plates, and at least some of said plates have recesses between the plinths, which together with an edge of a neighboring plate forms said openings between said spaces.
- 5. The structure according to claim 3 wherein at least one plate has a projection on the edge opposite the recess, which fits between the plinths of the plate which is contact with them.
- 6. The structure according to claim 4 wherein at least one plate has a projection on the edge opposite the recess, which fits between the plinths of the plate which is contact with them.
- 7. The structure according to claim 3 wherein said plates exhibit two plinths.
- 8. The structure according to claim 4 wherein said plates exhibit two plinths.
- 9. The structure according to claim 7 wherein the two lateral edges of said plates run in parallel straight lines.
- 10. The structure according to claim 4 wherein the two lateral edges of said plates run in parallel straight lines.
- 11. The structure according to claim 1 wherein said catalytic structure is for use with ammonia.
- 12. The structure according to claim 2 wherein said catalytic structure is for use with ammonia.
- 13. The structure according to claim 3 wherein said catalytic structure is for use with ammonia.
- 14. The structure according to claim 1 wherein said plates comprise at least one iron oxide.
- 15. The structure according to claim 10 wherein said plates comprise at least one iron oxide.
- 16. The structure according to claim 11 wherein said plates comprise at least one iron oxide.
- 17. The structure according to claim 14 wherein said at least one iron oxide comprises Fe.sub.2 O.sub.3.
- 18. The structure according to claim 1 wherein said structures of plates are disposed in substantially parallel planes.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3530544 |
Aug 1985 |
DEX |
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Parent Case Info
This application is a continuation-in-part of application Ser. No. 768,508, filed on Aug. 22, 1985, now U.S. Pat. No. 4,672,052, entitled "Catalyst for Removal of Nitrogen Oxides from Exhaust Gases", which corresponds to Federal Republic of Germany Patent Application No. P 34 30 886.5, filed on Aug. 22, 1984;
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4044102 |
Muraki et al. |
Aug 1977 |
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4131643 |
Utsunomiya et al. |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
768508 |
Aug 1985 |
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