EP0147275B1 - Foyer de combustion pour chaudière à lit fluidisé - Google Patents
Foyer de combustion pour chaudière à lit fluidisé Download PDFInfo
- Publication number
- EP0147275B1 EP0147275B1 EP84402448A EP84402448A EP0147275B1 EP 0147275 B1 EP0147275 B1 EP 0147275B1 EP 84402448 A EP84402448 A EP 84402448A EP 84402448 A EP84402448 A EP 84402448A EP 0147275 B1 EP0147275 B1 EP 0147275B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- combustion chamber
- tubes
- air
- injectors
- heat exchanger
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 37
- 238000005243 fluidization Methods 0.000 claims abstract description 18
- 238000001816 cooling Methods 0.000 claims description 3
- 230000005855 radiation Effects 0.000 claims description 3
- 239000012530 fluid Substances 0.000 claims description 2
- 239000013529 heat transfer fluid Substances 0.000 claims description 2
- 239000000446 fuel Substances 0.000 description 7
- 239000007789 gas Substances 0.000 description 6
- 238000007664 blowing Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 3
- 239000004449 solid propellant Substances 0.000 description 3
- 239000008187 granular material Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000007599 discharging Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000000135 prohibitive effect Effects 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C10/00—Fluidised bed combustion apparatus
- F23C10/002—Fluidised bed combustion apparatus for pulverulent solid fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B31/00—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus
- F22B31/0007—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus with combustion in a fluidized bed
- F22B31/0015—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus with combustion in a fluidized bed for boilers of the water tube type
- F22B31/003—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus with combustion in a fluidized bed for boilers of the water tube type with tubes surrounding the bed or with water tube wall partitions
- F22B31/0038—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus with combustion in a fluidized bed for boilers of the water tube type with tubes surrounding the bed or with water tube wall partitions with tubes in the bed
Definitions
- the subject of the invention is a combustion hearth for a boiler with a fluidized bed of solid fuel, which can be used industrially for all desired purposes: production of steam, hot water, hot gases, etc.
- EP-A-0 084 492 describes a fluidized bed hearth in which a particular solution is used which makes it possible to adjust the quantity of fuel burned in a ratio greater than 2.
- This solution consists in using a fluidization grid of special design in which there are two separate gas blowing circuits; one of these circuits, called the treatment gas circuit, has its outlet orifices which are situated at a level higher than that of the orifices of the fluidization gas circuit.
- the adjustment made possible using this solution is not perfect in all circumstances.
- the temperature rises too much inside the bed due to an insufficient evacuation of the calories produced; in addition, a non-negligible part of the fuel is drawn out of the bed, without being burnt.
- tubes of a heat exchanger are most often arranged horizontally, substantially in an area located near the upper part of the bed. This zone is made to fluctuate by acting on the speed of the fluidizing gas, so that the tubes of the heat exchanger are more or less completely immersed in the bed, the heat exchange coefficient being much higher at inside the bed than outside the bed.
- the main object of the invention is to arrive at another solution allowing the adjustment in a high ratio of the power of a combustion furnace in a fluidized bed, while retaining satisfactory operating conditions, that is to say does not not allowing an excessive rise in the temperature of the fluidized bed nor a significant loss of unburned products at the high speeds of the combustion air.
- air injectors for confining the combustion zone are arranged above the upper level in the vicinity of the side wall and directed towards the central zone of the hearth with an inclination to the vertical of an angle (a) between 15 ° and 75 °, the total air flow of containment blown by these injectors being adjustable between 5% and 20% of the total air flow introduced into the fireplace.
- your tubes or the bundles of tubes are distributed throughout the volume of the hearth, mainly when it is a large hearth.
- the tubes or the bundles of tubes are arranged on the side wall or in the vicinity of the side wall of the hearth, mainly when it comes to relatively small hearths, such as that of small boilers or small or medium boilers for relatively ashy fuels.
- the secondary air injectors are placed at the periphery of the hearth, at a level higher than the highest level reached by the tube bundle (s).
- the invention can be used with a fluidization grid of any type, from the moment when the inclined or vertical tubes can be arranged there.
- the invention can be used with a fluidization grid of special design with two separate circuits and with two staged levels of the blowing orifices as described in the aforementioned document.
- EP-A-0 084 492 will now be given a description of an exemplary embodiment of a combustion hearth. Reference will be made to the attached single figure which is a sectional view through a vertical plane of the hearth, according to the invention, of a steam boiler, the other parts of which, not concerned by the invention, are not shown.
- the hearth shown has a side wall 1 surrounding a square fluidizing grid 2. This is of the type with two separate blowing circuits 3, 4, both supplied with air since it is only a combustion hearth solid fuel.
- the first circuit 3 ends with orifices 3A open upwards in the upper face of the fluidization grid 2; the second circuit 4 ends with orifices 4A open horizontally at the top of vertical tubes 4B which extend upwards from the upper face of the grid 2, between the orifices 3A of the first circuit 3.
- the side wall 1 limits, with the fluidization grid 2, a volume 5 having a central zone 6.
- tubes 7, 8 are arranged vertically in the volume 5. They could be distributed equally throughout the volume 5; in this example, they are located in two parallel rows and arranged in staggered rows close to the side wall 1, so that the central zone 6 remains clear.
- the tubes 7, 8 are shown which are close to the vertical section plane and those which are further away have been omitted, for the sake of clarity of the drawing.
- the tubes 7 constitute a first bundle and the tubes 8 constitute a second bundle of a heat exchanger. At their lower end, they are connected to a manifold 9 for the arrival of a heat transfer fluid and at their upper end they are connected to a manifold 10 for discharging this fluid.
- a ramp 11 placed in a horizontal plane, provided with air injectors 12.
- the latter are distributed equally along the ramp 11 and they are directed towards the central zone 6 of the hearth at an angle a with the vertical.
- the air injectors 12 could be individually mounted on the side wall 1 and be supplied individually with air; as a further variant, the ramp 11 could be placed outside the side wall and connected thereto to each injector 12. In any case, the injectors 12 are determined and distributed so as to direct towards the central zone of the hearth, in a balanced manner, a total secondary air flow of between 5% and 20% of the total air flow introduced into the fireplace.
- the angle ⁇ of inclination of the air injectors 12 does not have a precise critical value; it can be chosen between 15 ° and 75 ° relative to the vertical, a preferred value being approximately 60 °.
- the air injectors 12 are movable in direction, so that the angle of inclination a can be modified according to the load of the bed.
- an automatic adjustment of this angle is provided, its value increasing as the level of the fluidized bed rises.
- the fluidized bed has a lower level 13 drawn in solid lines, in correspondence with the lowest thermal power obtained from the hearth and an upper level 14 drawn in lines mixed, corresponding to the highest thermal power obtained from the hearth.
- the tubes 7, 8 of the heat exchanger extend in a vertical direction substantially from the fluidization grid 2 to above the upper level 14 of the fluidized bed. In this latter operating state, at the maximum power of the hearth, the tubes 7, 8 are completely immersed in the fluidized bed; they then have their full efficiency in subtracting calories.
- the tubes 7, 8 are strictly vertical for this result to be obtained; they can be tilted vertically; they may also have an appearance other than straight.
- the tubes 7, 8 extend continuously at least from the lower level 13 of the fluidized bed and preferably from the fluidization grid 2 to the upper level 14 of the fluidized bed.
- the manifold 10 can be omitted and the tubes 7, 8 can be directly connected to the cooling tubes 15 which line the wall of the radiation and convection chamber 16 placed above the fluidization chamber as is known.
- the example described here shows that the invention is compatible with the use, known per se, of a heat exchanger with horizontal tubes 17 which are arranged in the vicinity of the lower level 13 of the fluidized bed.
- a circuit 18 for recycling inert materials for example ash.
- the level of the fluidized bed 2 rises at the same time as a dense turbulent zone develops so that the tubes 7, 8 have, simultaneously, an increasing efficiency.
- the air jets exiting through the air injectors 12 improve the combustion in the part of the fluidized bed located below the ramp and modify the circulation currents inside the latter.
- the air jets emitted by the air injectors 12 keep the solid particles inside the hearth for a longer time and reduce the size of the fraction of the partially burnt solid particles which escape prematurely from the hearth.
- the combined means provided by the invention make it possible to maintain in the hearth a temperature of between 850 and 950 ° C. when the power is modified in the ratio from 1 to 4, for example by a variation of 1 m / s to 4 m / s of the speed of the gases passing through the fluidized bed.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Fluidized-Bed Combustion And Resonant Combustion (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
- Treating Waste Gases (AREA)
- Solid-Fuel Combustion (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT84402448T ATE42390T1 (de) | 1983-12-02 | 1984-11-29 | Verbrennungsofen fuer wirbelbettkessel. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8319321A FR2556075B1 (fr) | 1983-12-02 | 1983-12-02 | Foyer de combustion pour chaudiere a lit fluidise |
FR8319321 | 1983-12-02 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0147275A2 EP0147275A2 (fr) | 1985-07-03 |
EP0147275A3 EP0147275A3 (en) | 1985-08-14 |
EP0147275B1 true EP0147275B1 (fr) | 1989-04-19 |
Family
ID=9294811
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP84402448A Expired EP0147275B1 (fr) | 1983-12-02 | 1984-11-29 | Foyer de combustion pour chaudière à lit fluidisé |
Country Status (11)
Country | Link |
---|---|
EP (1) | EP0147275B1 (es) |
JP (1) | JPS60248907A (es) |
AT (1) | ATE42390T1 (es) |
AU (1) | AU577073B2 (es) |
BR (1) | BR8406082A (es) |
CA (1) | CA1270706A (es) |
DE (1) | DE3477833D1 (es) |
ES (1) | ES538183A0 (es) |
FR (1) | FR2556075B1 (es) |
IN (1) | IN162288B (es) |
ZA (1) | ZA849114B (es) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2581161B1 (fr) * | 1985-04-29 | 1988-04-08 | Omnium Traitement Valorisa | Chaudiere a lit fluidise |
FR2591722B1 (fr) * | 1985-12-18 | 1988-02-19 | Charbonnages De France | Generateur thermique a lit fluidise a moyens ameliores d'evacuation des cendres et de recuperation de chaleur |
EP0319722A1 (de) * | 1987-12-09 | 1989-06-14 | Deutsche Kohle Marketing GmbH Steinkohlevertrieb-Wärmeversorgung | Brennkammer für atmosphärische stationäre Wirbelschichtfeuerung |
JP2835895B2 (ja) * | 1992-04-17 | 1998-12-14 | 株式会社荏原製作所 | 分割型流動床水管ボイラ |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4314967A (en) * | 1980-10-02 | 1982-02-09 | Dorr-Oliver Incorporated | Fluidized bed reactor with vertical cooling coils |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB858813A (en) * | 1957-06-11 | 1961-01-18 | Dingler Werke Ag | An improved furnace for fluidised bed combustion of solid fuels |
DE1401882A1 (de) * | 1962-12-20 | 1969-06-26 | Haniel & Lueg Gmbh | Verfahren zur Verbrennung von Klaerschlamm und Wirbelschichtofen zur Durchfuehrung desselben |
US3387590A (en) * | 1967-03-16 | 1968-06-11 | Interior Usa | System for regulating the total heat output in a burning fluidized bed heat exchanger or boiler |
CH496920A (fr) * | 1968-05-10 | 1970-09-30 | Rose Downs & Thompson Ltd | Procédé d'utilisation des résidus urbains et incinérateur pour sa mise en oeuvre |
GB1311869A (en) * | 1969-12-12 | 1973-03-28 | Foster Wheeler Brown Boilers | Steam boilers |
US3907674A (en) * | 1974-04-24 | 1975-09-23 | Dorr Oliver Inc | Fluid bed incineration of wastes containing alkali metal chlorides |
US4338887A (en) * | 1979-09-27 | 1982-07-13 | Dorr-Oliver Incorporated | Low profile fluid bed heater or vaporizer |
US4312919A (en) * | 1980-01-16 | 1982-01-26 | Devanney John W | Process of producing a non-agglomerating vanadium coated particle |
JPS57122203A (en) * | 1981-01-23 | 1982-07-30 | Babcock Hitachi Kk | Load control operation of fluidized bed boiler |
FR2519877B1 (fr) * | 1982-01-20 | 1986-10-31 | Charbonnages De France | Grille de fluidisation ainsi que foyer de combustion a grille inferieure de soufflage d'air et procede de traitement de matiere particulaire dans une chambre de fluidisation et/ou d'entrainement |
US4449482A (en) * | 1982-04-28 | 1984-05-22 | Dorr-Oliver Incorporated | Fluidized bed boilers |
-
1983
- 1983-12-02 FR FR8319321A patent/FR2556075B1/fr not_active Expired
-
1984
- 1984-11-22 ZA ZA849114A patent/ZA849114B/xx unknown
- 1984-11-28 IN IN928/MAS/84A patent/IN162288B/en unknown
- 1984-11-29 EP EP84402448A patent/EP0147275B1/fr not_active Expired
- 1984-11-29 DE DE8484402448T patent/DE3477833D1/de not_active Expired
- 1984-11-29 BR BR8406082A patent/BR8406082A/pt not_active IP Right Cessation
- 1984-11-29 AT AT84402448T patent/ATE42390T1/de not_active IP Right Cessation
- 1984-11-30 CA CA000469040A patent/CA1270706A/fr not_active Expired - Fee Related
- 1984-11-30 ES ES538183A patent/ES538183A0/es active Granted
- 1984-11-30 AU AU36091/84A patent/AU577073B2/en not_active Ceased
- 1984-11-30 JP JP59252064A patent/JPS60248907A/ja active Granted
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4314967A (en) * | 1980-10-02 | 1982-02-09 | Dorr-Oliver Incorporated | Fluidized bed reactor with vertical cooling coils |
Also Published As
Publication number | Publication date |
---|---|
AU577073B2 (en) | 1988-09-15 |
DE3477833D1 (en) | 1989-05-24 |
JPH0235889B2 (es) | 1990-08-14 |
EP0147275A3 (en) | 1985-08-14 |
CA1270706A (fr) | 1990-06-26 |
FR2556075A1 (fr) | 1985-06-07 |
EP0147275A2 (fr) | 1985-07-03 |
ATE42390T1 (de) | 1989-05-15 |
ES8603988A1 (es) | 1986-01-01 |
IN162288B (es) | 1988-04-23 |
ES538183A0 (es) | 1986-01-01 |
FR2556075B1 (fr) | 1988-08-19 |
AU3609184A (en) | 1985-06-06 |
BR8406082A (pt) | 1985-09-24 |
ZA849114B (en) | 1985-07-31 |
JPS60248907A (ja) | 1985-12-09 |
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