Claims
- 1. A fluidised bed combuster comprising a housing having an air diffuser bed support arranged to support and fluidise a bed of granular material in the housing, and at least one baffle extending in a generally vertical plane and vertically spaced from the bed support to define on one side of the bed a quiet zone of bed material which is not fluidised in operation in communication beneath the baffle with the remainder of the bed which is fluidised in operation, the top of the baffle lying below the upper surface of the bed in operation so that material from the fluidised bed flows over the baffle into the quiet zone, the combuster including feed means arranged to feed material to be burnt into the quiet zone for passage from that zone under the baffle into the fluidised zone in operation.
- 2. A combuster as claimed in claim 1, including two such baffles so arranged on opposed sides of the bed support to define two quiet zones each with means for feeding material burnt into it.
- 3. A combuster according to claim 1, wherein means is provided to selectively control the supply of air to the diffuser bed support whereby a bed supported thereby may be fluidised to different degrees in different portions thereof so that it is caused to circulate about a horizontal axis.
- 4. A combuster according to claim 1, wherein the diffuser bed support is planar and generally rectangular in plan, and is arranged to slope downwards from one edge to the opposite edge, and an ash trough is provided along said opposite edge.
- 5. A combuster according to claim 4 wherein the ash trough includes an ash extraction means.
- 6. A combuster according to claim 5 wherein the ash extraction means comprises a selectively operable flap valve to control the output of ash from the trough, and pneumatic conveyor means for conveying ash from downstream of the flap valve.
- 7. A combuster according to claim 2, wherein said feed means comprises a hopper and conveyor means to carry material from the hopper to a bifurcated conduit arranged to feed material to be burnt to said two quiet zones.
- 8. A combuster according to claim 1 including a baffle structure disposed to lie over the surface of a portion of a bed of granular material supported on said air diffuser bed support.
- 9. A combuster according to claim 8 wherein said baffle structure is disposed to continue above the remainder of a bed of granular material supported on said air diffuser bed support to form a labyrinth path in said housing for combustion gases leaving such bed in operation.
- 10. A combuster according to claim 1 wherein said housing is provided with an air cooling jacket, and means is provided to circulate air supplied to said diffuser bed support through the air cooling jacket to pre-heat it.
- 11. A combuster according to claim 1 including heat exchange elements disposed to be in contact with the combustion gases leaving a fluidised bed in operation to extract combustion heat from the combuster.
- 12. A combuster according to claim 1 including heat exchange elements disposed to lie in the fluidised bed in operation to extract combustion heat from the combuster.
- 13. A combuster according to claim 1 wherein said housing is provided with a water jacket to cool it and extract combustion heat from the combuster.
- 14. A combuster according to claim 1 including a further air diffuser bed support arranged in a chamber associated with said housing to support and fluidise a further bed of granular material in the chamber, the chamber being provided with inlet means for material to be burnt to enter such further fluidised bed for preliminary combustion therein, and outlet means to feed partially combusted material to said quiet zones.
- 15. A combuster according to claim 14, wherein said oulet means from said chamber is provided with feed control valve means.
- 16. A combuster according to claim 1 wherein said housing is constructed as a circular cross-section cylindrical pressure vessel so that the combuster may operate at above ambient atmospheric pressure.
Priority Claims (2)
Number |
Date |
Country |
Kind |
34814/77 |
Aug 1977 |
GBX |
|
48928/77 |
Nov 1977 |
GBX |
|
Parent Case Info
This application is a continuation of Ser. No. 934,921, 8-18-78, abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
498034 |
Sep 1967 |
FRX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
934921 |
Aug 1978 |
|