EP0936405B1 - Circulating fluidized bed boiler with improved NOx reduction - Google Patents

Circulating fluidized bed boiler with improved NOx reduction Download PDF

Info

Publication number
EP0936405B1
EP0936405B1 EP99400288A EP99400288A EP0936405B1 EP 0936405 B1 EP0936405 B1 EP 0936405B1 EP 99400288 A EP99400288 A EP 99400288A EP 99400288 A EP99400288 A EP 99400288A EP 0936405 B1 EP0936405 B1 EP 0936405B1
Authority
EP
European Patent Office
Prior art keywords
flow
reagent
boiler
fluidized bed
injection tube
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 - Lifetime
Application number
EP99400288A
Other languages
German (de)
French (fr)
Other versions
EP0936405A1 (en
Inventor
Jean Xavier Morin
Michel Vandycke
Corinne Beal
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alstom Power Boiler SA
Original Assignee
Alstom Power Boiler SA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Alstom Power Boiler SA filed Critical Alstom Power Boiler SA
Publication of EP0936405A1 publication Critical patent/EP0936405A1/en
Application granted granted Critical
Publication of EP0936405B1 publication Critical patent/EP0936405B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23CMETHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C10/00Fluidised bed combustion apparatus
    • F23C10/02Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed
    • F23C10/04Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone
    • F23C10/08Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone characterised by the arrangement of separation apparatus, e.g. cyclones, for separating particles from the flue gases
    • F23C10/10Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone characterised by the arrangement of separation apparatus, e.g. cyclones, for separating particles from the flue gases the separation apparatus being located outside the combustion chamber
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J15/00Arrangements of devices for treating smoke or fumes
    • F23J15/003Arrangements of devices for treating smoke or fumes for supplying chemicals to fumes, e.g. using injection devices
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23CMETHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C2206/00Fluidised bed combustion
    • F23C2206/10Circulating fluidised bed
    • F23C2206/103Cooling recirculating particles
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J2215/00Preventing emissions
    • F23J2215/10Nitrogen; Compounds thereof
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J2219/00Treatment devices
    • F23J2219/20Non-catalytic reduction devices

Definitions

  • the invention relates to a circulating fluidized bed boiler, with a duct which extends in a longitudinal direction and which channels a flow of particles and gases containing nitrogen oxides, and a means for injecting into the flow a reagent making it possible to reduce nitrogen oxides.
  • WO 96 21825 describes a bed boiler circulating fluidized additionally comprising an external bed heat exchanger fluidized.
  • an injection of reagent, ammonia, to reducing nitrogen oxides is done in the post- / combustion part from the fire or at the entrance to the separation cyclone.
  • the object of the invention is to improve the mixing of the reagent with the nitrogen oxides contained in the gases to promote their reduction.
  • the invention relates to a fluidized bed boiler circulating with a combustion hearth and a cyclone of separation linked together by a conduit which extends along a longitudinal direction and which channels a flow of particles and gases containing nitrogen oxides, and means for injecting into the stream a reagent for reducing nitrogen oxides, and further comprising an external exchanger with a dense fluidized bed connecting the separation cyclone to the combustion furnace, characterized in that the upper part of said exchanger forms a conduit for the flow of particles and gas which extends in a longitudinal direction and in that said means for injecting said reagent comprises at least one tubular rod placed in said upper part of the exchanger exterior, arranged so as to inject the reagent in the longitudinal direction of the conduit and co-routinely to the flow.
  • the reagent is injected right into the flow and in a region of the flow sparse in particles which allows strengthen the mixture with nitrogen oxides and increase the reduction yield.
  • a circulating fluidized bed boiler shown schematic in Figure 1, includes a combustion hearth 1 which extends vertically and a lower part of which is supplied by a fuel 3, for example crushed coal, and by a flow air 7 directed towards the top of the fireplace. Combustion takes place within a large mass of fine ash particles 5 strongly agitated and kept in suspension by the air flow 7 to form a fluidized bed having a particle density which decreases rapidly in depending on the height of the fireplace. Combustion takes place at a typical temperature of 850 degrees Celsius (° C) and generates NOx nitrogen oxides.
  • the air flow charged with fine particles and nitrogen oxides is channeled in the upper part of the hearth by a first conduit 9 which extends in a longitudinal direction L1 substantially horizontal and which opens into the upper part 11A of a cyclone of separation 11 arranged vertically.
  • a first conduit 9 which extends in a longitudinal direction L1 substantially horizontal and which opens into the upper part 11A of a cyclone of separation 11 arranged vertically.
  • the fumes 14 exit from the separation cyclone 11 and pass through heat exchangers conventional before being evacuated by a chimney.
  • a second conduit 17 forming an upper part of the exchanger exterior 15 extends parallel to a longitudinal direction L2 substantially horizontal and channels the flow of particles and gases from the separation cyclone 11 to the combustion furnace 1 through a fluidized system 19 to recycle the particles.
  • a reagent is injected, for example from ammonia in the gaseous state, by means of at least one tubular cane arranged so as to release the reagent in the direction longitudinal of line 17 and co-current with the flow of charged gas particles.
  • each tubular rod 21 is disposed in a second conduit 17 formed by an upper part 17A of the external exchanger 15, where the carbon is partially elutriated in particles from the cyclone 11.
  • the combustion of elutriated carbon takes place in a strong excess of air above the dense fluidized bed and produces oxides nitrogen which are reduced by injecting the reagent.
  • each tubular rod 21 is arranged in relation to the flow current downstream of the entry zone 17B in the second conduit 17 particles from the cyclone 11 to extend the residence time of the reagent, account given the fact that in this entry zone 17B, the carbon elutriation is important.
  • Each tubular rod 21 includes, figure 3, at least one injection nozzle 23.
  • Each tubular rod 21 is lowered into the second conduit 17, substantially perpendicular to the longitudinal direction L2 and by orienting the injection nozzle 23 in the direction of flow of the flow of particles and gases to inject the reagent according to the longitudinal direction of the conduit and co-current to the flow.
  • each injection nozzle 21 in the second conduit 17 is made by means of a flange 25 which preferably allows a translational movement of each rod perpendicular to the longitudinal direction of the duct to adjust the descent in the leads according to a lower density in particles in the flow and thus reinforce the mixing of the reagent with the nitrogen oxides.
  • each tubular rod is treated by depositing for example by plasma, a coating of tungsten carbide or carbide chromium.
  • a circulation of water 27 The reagent is injected through a channel 29 which opens out through the injection nozzle 23.
  • ammonia gas is used, or droplets ammonia solution, or a liquid ammonia precursor like urea in solution, pulsed by air.

Description

L'invention se rapporte à une chaudière à lit fluidisé circulant, avec un conduit qui s'étend suivant une direction longitudinale et qui canalise un flux de particules et de gaz contenant des oxydes d'azote, et un moyen pour injecter dans le flux un réactif permettant de réduire les oxydes d'azote.The invention relates to a circulating fluidized bed boiler, with a duct which extends in a longitudinal direction and which channels a flow of particles and gases containing nitrogen oxides, and a means for injecting into the flow a reagent making it possible to reduce nitrogen oxides.

Dans une chaudière de ce type, avec un conduit reliant un foyer de combustion à un cyclone de séparation, les particules sont séparées dans le cyclone de séparation et sont recyclées dans le foyer de combustion. Les gaz sont évacués par une cheminée après avoir traversé des échangeurs de chaleur conventionnels situés en aval du cyclone de séparation. La réduction des oxydes d'azote en azote moléculaire inerte est une mesure corrective qui permet de diminuer le rejet des oxydes d'azote avec les gaz évacués par la cheminée.In a boiler of this type, with a duct connecting a fireplace combustion at a separation cyclone, the particles are separated in the separation cyclone and are recycled in the combustion hearth. The gases are evacuated through a chimney after have passed through conventional heat exchangers located in downstream of the separation cyclone. Reducing nitrogen oxides to inert molecular nitrogen is a corrective measure which reduce the rejection of nitrogen oxides with the gases evacuated by the fireplace.

D'une manière générale, on injecte dans le flux de particules et de gaz de l'ammoniac pour réduire les oxydes d'azote selon un schéma réactionnel connu sous le nom de réduction sélective non catalytique. Il est admis aujourd'hui que trois principaux paramètres, la température, le temps de séjour, et le mélange de l'ammoniac réactif avec les oxydes d'azote, influencent la réaction de réduction dans l'installation.Generally, we inject into the particle flow and ammonia gas to reduce nitrogen oxides according to a reaction scheme known as selective reduction no Catalytic. It is now accepted that three main parameters, the temperature, residence time, and mixture of reactive ammonia with nitrogen oxides influence the reduction reaction in installation.

Le document WO 96 21825 décrit une chaudière à lit fluidisé circulant comportant en outre un échangeur extérieure à lit fluidisé. Dans ce document, une injection de réactif, de l'ammoniac, pour réduire les oxydes d'azote est faite dans la partie post-/combustion du foyer ou bien à l'entrée du cyclone de séparation. WO 96 21825 describes a bed boiler circulating fluidized additionally comprising an external bed heat exchanger fluidized. In this document, an injection of reagent, ammonia, to reducing nitrogen oxides is done in the post- / combustion part from the fire or at the entrance to the separation cyclone.

Le but de l'invention est d'améliorer le mélange du réactif avec les oxydes d'azote contenus dans les gaz pour favoriser leur réduction.The object of the invention is to improve the mixing of the reagent with the nitrogen oxides contained in the gases to promote their reduction.

A cet effet, l'invention a pour objet une chaudière à lit fluidisé circulant avec un foyer de combustion et un cyclone de séparation reliés entre eux par un conduit qui s'étend suivant une direction longitudinale et qui canalise un flux de particules et de gaz contenant des oxydes d'azote, et un moyen pour injecter dans le flux un réactif permettant dé réduire les oxydes d'azote, et comprenant en outre un échangeur extérieure à lit fluidisé dense reliant le cyclone de séparation au foyer de combustion, caractérisé en ce que la partie supérieure dudit échangeur forme un conduit pour le flux de particules et de gaz qui s'étend suivant une direction longitudinale et en ce que ledit moyen pour injecter ledit réactif comprend au moins une canne tubulaire disposée dans ladite partie supérieure de l'échangeur extérieur, disposée de façon telle à injecter le réactif suivant la direction longitudinale du conduit et de façon co-courante au flux.To this end, the invention relates to a fluidized bed boiler circulating with a combustion hearth and a cyclone of separation linked together by a conduit which extends along a longitudinal direction and which channels a flow of particles and gases containing nitrogen oxides, and means for injecting into the stream a reagent for reducing nitrogen oxides, and further comprising an external exchanger with a dense fluidized bed connecting the separation cyclone to the combustion furnace, characterized in that the upper part of said exchanger forms a conduit for the flow of particles and gas which extends in a longitudinal direction and in that said means for injecting said reagent comprises at least one tubular rod placed in said upper part of the exchanger exterior, arranged so as to inject the reagent in the longitudinal direction of the conduit and co-routinely to the flow.

Avec cet agencement, le réactif est injecté à coeur dans le flux et dans un région du flux peu dense en particules ce qui permet de renforcer le mélange avec les oxydes d'azote et d'augmenter le rendement de réduction.With this arrangement, the reagent is injected right into the flow and in a region of the flow sparse in particles which allows strengthen the mixture with nitrogen oxides and increase the reduction yield.

D'autres caractéristiques et avantages de l'invenfion apparaítront à la lecture de la description faite ci-après en référence au dessin annexé dans lequel:

  • La figure 1 montre très schématiquement en vue de face une chaudière à lit fluidisé circulant avec un échangeur extérieur à lit fluidisé dense.
  • La figure 2 montre très schématiquement la partie inférieure de la chaudière selon la figure 1, avec au moins une canne d'injection disposée dans le conduit formé par la partie supérieure de l'échangeur extérieur à lit fluidisé dense.
  • La figure 3 est une vue en coupe d'une canne d'injection.
  • Other characteristics and advantages of the invention will appear on reading the description given below with reference to the attached drawing in which:
  • FIG. 1 very schematically shows a front view of a fluidized bed boiler circulating with an external exchanger with a dense fluidized bed.
  • FIG. 2 very schematically shows the lower part of the boiler according to FIG. 1, with at least one injection pipe disposed in the duct formed by the upper part of the external exchanger with a dense fluidized bed.
  • Figure 3 is a sectional view of an injection pipe.
  • Une chaudière à lit fluidisé circulant, représentée de façon schématique sur la figure 1, comprend un foyer de combustion 1 qui s'étend verticalement et dont une partie inférieure est alimentée par un combustible 3, par exemple du charbon concassé, et par un flux d'air 7 dirigé vers le haut du foyer. La combustion s'effectue au sein d'une importante masse de fines particules de cendres 5 fortement agitées et maintenues en suspension par le flux d'air 7 pour former un lit fluidisé ayant une densité en particules qui diminue rapidement en fonction de la hauteur du foyer. La combustion a lieu à une température typique de 850 degrés celsius (°C) et génère des d'oxydes d'azote NOx.A circulating fluidized bed boiler, shown schematic in Figure 1, includes a combustion hearth 1 which extends vertically and a lower part of which is supplied by a fuel 3, for example crushed coal, and by a flow air 7 directed towards the top of the fireplace. Combustion takes place within a large mass of fine ash particles 5 strongly agitated and kept in suspension by the air flow 7 to form a fluidized bed having a particle density which decreases rapidly in depending on the height of the fireplace. Combustion takes place at a typical temperature of 850 degrees Celsius (° C) and generates NOx nitrogen oxides.

    Le flux d'air chargé des fines particules et des oxydes d'azote est canalisé dans la partie haute du foyer par un premier conduit 9 qui s'étend suivant une direction longitudinale L1 sensiblement horizontale et qui débouche dans la partie haute 11A d'un cyclone de séparation 11 disposé verticalement. Par un écoulement circulaire du flux d'air dans le cyclone, les fines particules de cendre sont séparées des fumées et sont recyclées vers le foyer de combustion 1 par l'intermédiaire d'un siphon fluidisé 13. Les fumées 14 sortent du cyclone de séparation 11 et traversent des échangeurs de chaleur conventionnels avant d'être évacuées par une cheminée.The air flow charged with fine particles and nitrogen oxides is channeled in the upper part of the hearth by a first conduit 9 which extends in a longitudinal direction L1 substantially horizontal and which opens into the upper part 11A of a cyclone of separation 11 arranged vertically. By a circular flow of the air flow in the cyclone, the fine ash particles are separated fumes and are recycled to the combustion chamber 1 by via a fluidized siphon 13. The fumes 14 exit from the separation cyclone 11 and pass through heat exchangers conventional before being evacuated by a chimney.

    Pour faciliter le contrôle de la température du foyer, on dispose en parallèle avec le siphon fluidisé 13, un échangeur extérieur à lit fluidisé dense 15, qui est alimenté en air 16 et en particules prélevées dans la partie inférieure 11B du cyclone de séparation 11. Un deuxième conduit 17 formant une partie supérieure de l'échangeur extérieur 15 s'étend parallèlement à une direction longitudinale L2 sensiblement horizontale et canalise le flux des particules et de gaz provenant du cyclone de séparation 11 vers le foyer de combustion 1 par l'intermédiaire d'un système fluidisé 19 pour recycler les particules.To facilitate control of the hearth temperature, in parallel with the fluidized siphon 13, an external exchanger with a bed dense fluidized 15, which is supplied with air 16 and particles removed in the lower part 11B of the separation cyclone 11. A second conduit 17 forming an upper part of the exchanger exterior 15 extends parallel to a longitudinal direction L2 substantially horizontal and channels the flow of particles and gases from the separation cyclone 11 to the combustion furnace 1 through a fluidized system 19 to recycle the particles.

    Selon l'invention, pour réduire les oxydes d'azote contenus dans les gaz et les fumées, on injecte un réactif, par exemple de l'ammoniac à l'état gazeux, au moyen d'au moins une canne tubulaire disposée de façon telle à libérer le réactif suivant la direction longitudinale du conduit 17 et de façon co-courante au flux de gaz chargé des particules. According to the invention, to reduce the nitrogen oxides contained in gases and fumes, a reagent is injected, for example from ammonia in the gaseous state, by means of at least one tubular cane arranged so as to release the reagent in the direction longitudinal of line 17 and co-current with the flow of charged gas particles.

    Ainsi, comme le montre la figure 2, au-moins une canne tubulaire 21 (deux dans l'exemple décrit) est disposée dans un deuxième conduit 17 formé par une partie supérieure 17A de l'échangeur extérieur 15, où le carbone est élutrié en partie dans les particules provenant du cyclone de séparation 11. La combustion du carbone élutrié s'effectue dans un fort excès d'air au dessus du lit fluidisé dense et produit des oxydes d'azote qui sont réduits par l'injection du réactif. De préférence, chaque canne tubulaire 21 est disposée par rapport au courant du flux en aval de la zone d'entrée 17B dans le deuxième conduit 17 des particules provenant du cyclone de séparation 11 pour allonger le temps de séjour du réactif, compte tenu du fait que dans cette zone d'entrée 17B, l'élutriation du carbone est importante.So, as shown in Figure 2, at least a tubular rod 21 (two in the example described) is disposed in a second conduit 17 formed by an upper part 17A of the external exchanger 15, where the carbon is partially elutriated in particles from the cyclone 11. The combustion of elutriated carbon takes place in a strong excess of air above the dense fluidized bed and produces oxides nitrogen which are reduced by injecting the reagent. Preferably, each tubular rod 21 is arranged in relation to the flow current downstream of the entry zone 17B in the second conduit 17 particles from the cyclone 11 to extend the residence time of the reagent, account given the fact that in this entry zone 17B, the carbon elutriation is important.

    Chaque canne tubulaire 21 comprend, figurer 3, au moins une buse d'injection 23. Chaque canne tubulaire 21 est descendue dans le deuxième conduit 17, sensiblement perpendiculairement à la direction longitudinale L2 et en orientant la buse d'injection 23 dans le sens d'écoulement du flux des particules et des gaz pour injecter le réactif suivant la direction longitudinale du conduit et de façon co-courante au flux. Each tubular rod 21 includes, figure 3, at least one injection nozzle 23. Each tubular rod 21 is lowered into the second conduit 17, substantially perpendicular to the longitudinal direction L2 and by orienting the injection nozzle 23 in the direction of flow of the flow of particles and gases to inject the reagent according to the longitudinal direction of the conduit and co-current to the flow.

    La fixation de chaque canne d'injection 21 dans le deuxième conduit 17 est réalisée au moyen d'une bride 25 qui de préférence permet un déplacement en translation de chaque canne perpendiculairement à la direction longitudinale du conduit pour régler la descente dans le conduit en fonction d'une moindre densité en particules dans le flux et ainsi renforcer le mélange du réactif avec les oxydes d'azote.The fixing of each injection nozzle 21 in the second conduit 17 is made by means of a flange 25 which preferably allows a translational movement of each rod perpendicular to the longitudinal direction of the duct to adjust the descent in the leads according to a lower density in particles in the flow and thus reinforce the mixing of the reagent with the nitrogen oxides.

    Il est prévu également de traiter chaque canne tubulaire en surface pour améliorer ses propriétés de tenue à la corrosion. Compte tenu de la température du flux et de la nature abrasive des particules et des gaz, on traite chaque canne en déposant par exemple par plasma, un revêtement de carbure de tungstène ou de carbure de chrome. Pour améliorer la tenue mécanique des cannes, on prévoit également de les refroidir par une circulation d'eau 27. Le réactif est injecté par un canal 29 qui débouche par la buse d'injection 23. Comme réactif, on utilise de l'ammoniac gazeux, ou des gouttelettes d'ammoniaque en solution, ou un précurseur liquide de l'ammoniac comme l'urée en solution, pulsé par de l'air.It is also planned to treat each tubular rod in surface to improve its corrosion resistance properties. Account given the temperature of the flux and the abrasive nature of the particles and gases, each rod is treated by depositing for example by plasma, a coating of tungsten carbide or carbide chromium. To improve the mechanical strength of the rods, provision is made also to cool them by a circulation of water 27. The reagent is injected through a channel 29 which opens out through the injection nozzle 23. As reagent, ammonia gas is used, or droplets ammonia solution, or a liquid ammonia precursor like urea in solution, pulsed by air.

    Claims (6)

    1. A circulating fluidized bed boiler having a combustion hearth and a separator cyclone (11) interconnected by a duct (9) which extends along a longitudinal axis (L1) and which channels a flow of particles and of gas containing nitrogen oxides (NOx), and means for injecting into the flow a reagent that enables the nitrogen oxides to be reduced, and the boiler further comprising an external dense fluidized bed heat exchanger (15) connecting the separator cyclone (11) to the combustion hearth (1), the boiler being characterized in that the top portion (17A) of said exchanger forms a duct (17) for a flow of particles and gas extending along a longitudinal axis (L2), and in that said means for injecting said reagent comprises at least one injection tube (21) disposed in said top portion (17A) of the external heat exchanger (15) to inject the reagent into said flow and disposed so as to inject the reagent along said longitudinal axis (L2) of the duct (17) and in the same direction as the flow.
    2. A boiler according to claim 1, in which each injection tube (21) has at least one reagent injection nozzle (23).
    3. A boiler according to claim 1 or claim 2, in which each injection tube (21) is movable in a direction that is substantially perpendicular to the longitudinal axis (L1, L2) of the duct (9, 17).
    4. A boiler according to any one of claims 1 to 3, in which each injection tube (21) has a cooling circuit (27) using a flow of water.
    5. A boiler according to any one of claims 1 to 4, in which each injection tube (21) has a plasma coating of tungsten carbide or of chromium carbide for withstanding abrasion by the flow.
    6. A boiler according to any preceding claim, in which the reagent is gaseous ammonia, or droplets of ammonia in solution, or of a liquid precursor of ammonia such as urea in solution, driven by air.
    EP99400288A 1998-02-16 1999-02-09 Circulating fluidized bed boiler with improved NOx reduction Expired - Lifetime EP0936405B1 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    FR9801839 1998-02-16
    FR9801839A FR2775061B1 (en) 1998-02-16 1998-02-16 CIRCULATING FLUIDIZED BED BOILER WITH IMPROVED NITROGEN OXIDE REDUCTION

    Publications (2)

    Publication Number Publication Date
    EP0936405A1 EP0936405A1 (en) 1999-08-18
    EP0936405B1 true EP0936405B1 (en) 2004-08-18

    Family

    ID=9523008

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP99400288A Expired - Lifetime EP0936405B1 (en) 1998-02-16 1999-02-09 Circulating fluidized bed boiler with improved NOx reduction

    Country Status (7)

    Country Link
    US (1) US6067943A (en)
    EP (1) EP0936405B1 (en)
    CN (1) CN1135319C (en)
    DE (1) DE69919424T2 (en)
    ES (1) ES2227980T3 (en)
    FR (1) FR2775061B1 (en)
    MX (1) MXPA99001556A (en)

    Cited By (5)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US7670569B2 (en) 2003-06-13 2010-03-02 Mobotec Usa, Inc. Combustion furnace humidification devices, systems & methods
    US8069825B1 (en) 2005-11-17 2011-12-06 Nalco Mobotec, Inc. Circulating fluidized bed boiler having improved reactant utilization
    US8069824B2 (en) 2008-06-19 2011-12-06 Nalco Mobotec, Inc. Circulating fluidized bed boiler and method of operation
    DE102010036749A1 (en) 2010-07-19 2012-01-19 Heizkraftwerksgesellschaft Cottbus Mbh Method for reducing deposits in boilers, involves inserting fresh water in combustion chamber, particularly in proximity of boiler tube during current operation
    US8449288B2 (en) 2003-03-19 2013-05-28 Nalco Mobotec, Inc. Urea-based mixing process for increasing combustion efficiency and reduction of nitrogen oxides (NOx)

    Families Citing this family (11)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    FR2803020B1 (en) * 1999-12-22 2002-04-12 Abb Alstom Power Comb PROCESS FOR REDUCING NITROGEN OXIDE EMISSIONS IN A FLUIDIZED BED COMBUSTION PLANT
    US6269778B1 (en) * 1999-12-17 2001-08-07 The Babcock & Wilcox Company Fine solids recycle in a circulating fluidized bed
    US8353698B2 (en) * 2003-06-13 2013-01-15 Nalco Mobotec, Inc. Co-axial injection system
    US8251694B2 (en) 2004-02-14 2012-08-28 Nalco Mobotec, Inc. Method for in-furnace reduction flue gas acidity
    WO2008137548A1 (en) * 2007-05-01 2008-11-13 Phase Inc. Methods and apparatus for classification of suspended materials
    US8555797B2 (en) * 2007-05-10 2013-10-15 Alstom Technology Ltd System and method for decreasing NOx emissions from a fluidized bed combustion system
    AT505526B1 (en) * 2007-08-14 2010-09-15 Univ Wien Tech FLUID BED REACTOR SYSTEM
    DE102011052788B4 (en) 2011-08-17 2014-03-20 Harald Sauer Process and apparatus for purifying exhaust gases
    CN102626586B (en) * 2012-04-01 2014-06-04 无锡雪浪环境科技股份有限公司 Treatment device for emission reduction control over nitrogen oxide in flue gas
    US10746141B2 (en) * 2017-03-14 2020-08-18 Kohler Co. Engine air cleaner
    US10653996B1 (en) * 2019-05-13 2020-05-19 The Babcock & Wilcox Company Selective non-catalytic reduction (SNCR) of NOx in fluidized bed combustion reactors

    Family Cites Families (8)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    DE3728557A1 (en) * 1987-08-27 1989-03-09 Didier Eng Process for the distribution of ammonia in a gas stream and apparatus for carrying out the process
    SE466814B (en) * 1989-06-01 1992-04-06 Kvaerner Generator Ab DEVICE FOR DEGRADATION OF GASES GENERATED FOR PRESENT BURNING AT UNGEFER 850 DEGREES C OF THE SOLID BROWN IN A LIQUID BED
    US5342592A (en) * 1989-07-04 1994-08-30 Fuel Tech Europe Ltd. Lance-type injection apparatus for introducing chemical agents into flue gases
    GB2271517A (en) * 1992-10-14 1994-04-20 Dorr Oliver Inc Flue gas NOx reduction in a fluidized bed reactor
    US5315941A (en) * 1993-06-07 1994-05-31 The Babcock & Wilcox Company Method and apparatus for injecting nox inhibiting reagent into the flue gas of a boiler
    US5465690A (en) * 1994-04-12 1995-11-14 A. Ahlstrom Corporation Method of purifying gases containing nitrogen oxides and an apparatus for purifying gases in a steam generation boiler
    US5462718A (en) 1994-06-13 1995-10-31 Foster Wheeler Energy Corporation System for decreasing NOx emissions from a fluidized bed reactor
    CH689312A5 (en) * 1995-01-10 1999-02-15 Von Roll Umwelttechnik Ag Method for the combustion of waste material with production of thermal energy.

    Cited By (6)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US8449288B2 (en) 2003-03-19 2013-05-28 Nalco Mobotec, Inc. Urea-based mixing process for increasing combustion efficiency and reduction of nitrogen oxides (NOx)
    US7670569B2 (en) 2003-06-13 2010-03-02 Mobotec Usa, Inc. Combustion furnace humidification devices, systems & methods
    US8021635B2 (en) 2003-06-13 2011-09-20 Nalco Mobotec, Inc. Combustion furnace humidification devices, systems and methods
    US8069825B1 (en) 2005-11-17 2011-12-06 Nalco Mobotec, Inc. Circulating fluidized bed boiler having improved reactant utilization
    US8069824B2 (en) 2008-06-19 2011-12-06 Nalco Mobotec, Inc. Circulating fluidized bed boiler and method of operation
    DE102010036749A1 (en) 2010-07-19 2012-01-19 Heizkraftwerksgesellschaft Cottbus Mbh Method for reducing deposits in boilers, involves inserting fresh water in combustion chamber, particularly in proximity of boiler tube during current operation

    Also Published As

    Publication number Publication date
    FR2775061B1 (en) 2000-03-10
    FR2775061A1 (en) 1999-08-20
    CN1135319C (en) 2004-01-21
    CN1226653A (en) 1999-08-25
    ES2227980T3 (en) 2005-04-01
    DE69919424T2 (en) 2005-09-08
    DE69919424D1 (en) 2004-09-23
    US6067943A (en) 2000-05-30
    MXPA99001556A (en) 2004-10-28
    EP0936405A1 (en) 1999-08-18

    Similar Documents

    Publication Publication Date Title
    EP0936405B1 (en) Circulating fluidized bed boiler with improved NOx reduction
    EP1934309B1 (en) Device and process for gasifying biomass and organic wastes at a high temperature and with an external power supply for generating a high-quality synthesis gas
    EP0127513B1 (en) Method and apparatus for making glass
    EP0161970B1 (en) Method and installation for the treatment of material in a circulating fluidized bed
    EP2758711B1 (en) Chemical looping combustion method with removal of ash and fines in the reduction area, and a facility using such a method
    US20100095592A1 (en) Gasifier
    CH629886A5 (en) METHOD FOR COMBUSTING A CARBON FUEL.
    EP0173782B1 (en) Process for treating materials
    FR2473553A1 (en) METHOD AND APPARATUS FOR PERFORMING REDUCTION OF IRON OXIDE MATERIAL IN A FLUIDIZED BED
    RU2119959C1 (en) Gear to melt small particles presenting mixture of incombustible substances with solid materials containing carbon and process of melting of small particles with usage of this gear
    SE453751B (en) SET AND DEVICE FOR PARTIAL COMBUSTION AND GASING OF CARBON FUEL
    CA2196808A1 (en) Fluidized bed reactor for the heat treatment of waste material
    FR2735560A1 (en) Method of reducing pollution from fluidised bed combustion heater furnace
    EP0553019B1 (en) Method for burning solid fuels with a high content of fusible ashes and heavy metals
    EP0084279B1 (en) Process and installation for heat recuperation, in particular at the cooling of ashes
    EP1277825B1 (en) Process and installation for the production of combustible gas from gas derived from the thermal conversion of a solid charge
    FR2551184A1 (en) METHOD FOR INJECTING A PULVERULENT MATERIAL IN A BOILER FIREPLACE, AND DEVICE FOR CARRYING OUT SAID METHOD
    EP1184622A1 (en) Method of generating heat with reduced emission of sulphur oxides and low absorbant consumption
    FR2593891A1 (en) Combustion installation having a reaction chamber for a circulating fluidised bed
    BE1004481A6 (en) Method and device for the pyrometallurgical treatment of a pulverulentsubstance containing a compound of one or more metals
    FR2801895A1 (en) METHOD AND INSTALLATION FOR GASIFYING CARBON COMPOUNDS
    US4436286A (en) Process of afterburning combustible constituents of exhaust gases from rotary kilns
    EP0308300B1 (en) Combustion process in a fluidised bed and installation for carrying out the process
    FR2669099A1 (en) Process and device for burning divided carbonaceous materials
    FR3130651A1 (en) CYCLONE FOR AN INSTALLATION AND A COMBUSTION PROCESS IN A CHEMICAL LOOP WITH AN INLET PIPE WITH INCLINED WALLS AND GAS INJECTION

    Legal Events

    Date Code Title Description
    PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

    Free format text: ORIGINAL CODE: 0009012

    AK Designated contracting states

    Kind code of ref document: A1

    Designated state(s): BE DE ES GB GR IE IT PT

    AX Request for extension of the european patent

    Free format text: AL;LT;LV;MK;RO;SI

    17P Request for examination filed

    Effective date: 20000218

    AKX Designation fees paid

    Free format text: BE DE ES GB GR IE IT PT

    17Q First examination report despatched

    Effective date: 20020118

    RAP1 Party data changed (applicant data changed or rights of an application transferred)

    Owner name: ALSTOM POWER BOILERS

    GRAP Despatch of communication of intention to grant a patent

    Free format text: ORIGINAL CODE: EPIDOSNIGR1

    GRAS Grant fee paid

    Free format text: ORIGINAL CODE: EPIDOSNIGR3

    GRAA (expected) grant

    Free format text: ORIGINAL CODE: 0009210

    AK Designated contracting states

    Kind code of ref document: B1

    Designated state(s): BE DE ES GB GR IE IT PT

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: IT

    Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

    Effective date: 20040818

    Ref country code: IE

    Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

    Effective date: 20040818

    Ref country code: GB

    Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

    Effective date: 20040818

    REG Reference to a national code

    Ref country code: GB

    Ref legal event code: FG4D

    Free format text: NOT ENGLISH

    RIC1 Information provided on ipc code assigned before grant

    Ipc: 7F 23J 15/00 B

    Ipc: 7F 23C 10/02 A

    REG Reference to a national code

    Ref country code: IE

    Ref legal event code: FG4D

    Free format text: FRENCH

    REF Corresponds to:

    Ref document number: 69919424

    Country of ref document: DE

    Date of ref document: 20040923

    Kind code of ref document: P

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: GR

    Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

    Effective date: 20041118

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: BE

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20050228

    GBV Gb: ep patent (uk) treated as always having been void in accordance with gb section 77(7)/1977 [no translation filed]

    Effective date: 20040818

    REG Reference to a national code

    Ref country code: IE

    Ref legal event code: FD4D

    REG Reference to a national code

    Ref country code: ES

    Ref legal event code: FG2A

    Ref document number: 2227980

    Country of ref document: ES

    Kind code of ref document: T3

    PLBE No opposition filed within time limit

    Free format text: ORIGINAL CODE: 0009261

    STAA Information on the status of an ep patent application or granted ep patent

    Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

    26N No opposition filed

    Effective date: 20050519

    BERE Be: lapsed

    Owner name: *ALSTOM POWER BOILERS

    Effective date: 20050228

    BERE Be: lapsed

    Owner name: *ALSTOM POWER BOILERS

    Effective date: 20050228

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: PT

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20050118

    PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

    Ref country code: ES

    Payment date: 20090216

    Year of fee payment: 11

    REG Reference to a national code

    Ref country code: ES

    Ref legal event code: FD2A

    Effective date: 20110405

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: ES

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20110323

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: ES

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20100210

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE, DE

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER, BARTHELT & ABEL, DE

    Effective date: 20111026

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE PARTG MBB, DE

    Effective date: 20111026

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE, DE

    Effective date: 20111026

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: GENERAL ELECTRIC TECHNOLOGY GMBH, CH

    Free format text: FORMER OWNER: ALSTOM POWER BOILERS, VELIZY-VILLACOUBLAY, FR

    Effective date: 20111026

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: ALSTOM TECHNOLOGY LTD., CH

    Free format text: FORMER OWNER: ALSTOM POWER BOILERS, VELIZY-VILLACOUBLAY, FR

    Effective date: 20111026

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: ALSTOM POWER SYSTEMS SA, FR

    Free format text: FORMER OWNER: ALSTOM POWER BOILERS, VELIZY-VILLACOUBLAY, FR

    Effective date: 20111026

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE, DE

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER, BARTHELT & ABEL, DE

    Effective date: 20120123

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE PARTG MBB, DE

    Effective date: 20120123

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE, DE

    Effective date: 20120123

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: GENERAL ELECTRIC TECHNOLOGY GMBH, CH

    Free format text: FORMER OWNER: ALSTOM POWER BOILERS, MEUDON LA FORET, FR

    Effective date: 20120123

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: ALSTOM TECHNOLOGY LTD., CH

    Free format text: FORMER OWNER: ALSTOM POWER BOILERS, MEUDON LA FORET, FR

    Effective date: 20120123

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE, DE

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER, BARTHELT & ABEL, DE

    Effective date: 20120320

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: DREISS PATENTANWAELTE PARTG MBB, DE

    Effective date: 20120320

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: GENERAL ELECTRIC TECHNOLOGY GMBH, CH

    Free format text: FORMER OWNER: ALSTOM POWER SYSTEMS SA, LAVALLOIS PERRET CEDEX, FR

    Effective date: 20120320

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: ALSTOM TECHNOLOGY LTD., CH

    Free format text: FORMER OWNER: ALSTOM POWER SYSTEMS SA, LAVALLOIS PERRET CEDEX, FR

    Effective date: 20120320

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER ABEL PATENT- UND RECHTSANWAELTE, DE

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER, BARTHELT & ABEL, DE

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER ABEL PATENT- UND RECHTSANWAELTE, DE

    Ref country code: DE

    Ref legal event code: R082

    Ref document number: 69919424

    Country of ref document: DE

    Representative=s name: RUEGER, BARTHELT & ABEL, DE

    Ref country code: DE

    Ref legal event code: R081

    Ref document number: 69919424

    Country of ref document: DE

    Owner name: GENERAL ELECTRIC TECHNOLOGY GMBH, CH

    Free format text: FORMER OWNER: ALSTOM TECHNOLOGY LTD., BADEN, CH

    PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

    Ref country code: DE

    Payment date: 20170227

    Year of fee payment: 19

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R119

    Ref document number: 69919424

    Country of ref document: DE

    PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

    Ref country code: DE

    Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

    Effective date: 20180901