WO2009095121A1 - Installation pour la fabrication de ciment - Google Patents

Installation pour la fabrication de ciment Download PDF

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Publication number
WO2009095121A1
WO2009095121A1 PCT/EP2008/066005 EP2008066005W WO2009095121A1 WO 2009095121 A1 WO2009095121 A1 WO 2009095121A1 EP 2008066005 W EP2008066005 W EP 2008066005W WO 2009095121 A1 WO2009095121 A1 WO 2009095121A1
Authority
WO
WIPO (PCT)
Prior art keywords
plant
gases
calciner
cement
volatile components
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.)
Ceased
Application number
PCT/EP2008/066005
Other languages
English (en)
Inventor
Peter Rosholm
Kim Clausen
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.)
FLSmidth AS
Original Assignee
FLSmidth AS
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 FLSmidth AS filed Critical FLSmidth AS
Publication of WO2009095121A1 publication Critical patent/WO2009095121A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B7/00—Rotary-drum furnaces, i.e. horizontal or slightly inclined
    • F27B7/20—Details, accessories or equipment specially adapted for rotary-drum furnaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/002—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by condensation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D7/00—Sublimation
    • B01D7/02—Crystallisation directly from the vapour phase
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/36—Manufacture of hydraulic cements in general
    • C04B7/43—Heat treatment, e.g. precalcining, burning, melting; Cooling
    • C04B7/436—Special arrangements for treating part or all of the cement kiln dust
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/36—Manufacture of hydraulic cements in general
    • C04B7/43—Heat treatment, e.g. precalcining, burning, melting; Cooling
    • C04B7/44—Burning; Melting
    • C04B7/4492—Inhibiting the formation of or eliminating incrustations in the cement kiln
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/36—Manufacture of hydraulic cements in general
    • C04B7/60—Methods for eliminating alkali metals or compounds thereof, e.g. from the raw materials or during the burning process; methods for eliminating other harmful components
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D17/00—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
    • F27D17/20—Arrangements for treatment or cleaning of waste gases
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D17/00—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
    • F27D17/20—Arrangements for treatment or cleaning of waste gases
    • F27D17/22—Arrangements for treatment or cleaning of waste gases for removing solid constituents
    • F27D17/25—Arrangements for treatment or cleaning of waste gases for removing solid constituents using cyclones
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D17/00—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
    • F27D17/20—Arrangements for treatment or cleaning of waste gases
    • F27D17/28—Arrangements for treatment or cleaning of waste gases for cooling waste gases
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/20—Halogens or halogen compounds
    • B01D2257/204—Inorganic halogen compounds
    • B01D2257/2045—Hydrochloric acid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/70—Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
    • B01D2257/708—Volatile organic compounds V.O.C.'s
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
    • Y02P40/121—Energy efficiency measures, e.g. improving or optimising the production methods

Definitions

  • the present invention relates to a plant for manufacturing cement, which plant comprises a cyclone preheater for preheating cement raw materials, a calciner for calcination of preheated cement raw materials, a kiln for burning cement clinker, as well as means for removing volatile components, such as chloride, alkali and sulphur, from the cement manufacturing plant.
  • Cement manufacturing plants of the aforementioned kind are well known.
  • volatile components such as chloride, alkali and sulphur
  • Khi a compound that will be introduced together with the cement raw materials and the fuel.
  • These volatile components will circulate in the kiln system of the plant between the burning zone in which they undergo evaporation and the preheater zone in which they undergo condensation, and may cause clogging and unsteady kiln operation.
  • KCI One of the most common chloride compounds circulating in the kiln system is KCI .
  • the known plants use a bypass which is located in immediate proximity of the exhaust gas outlet of the kiln in order to divert a portion of the exhaust gases from the kiln, typically between 2 and 10 per cent of the kiln exhaust gases, thereby ensuring continuous extraction of volatile components from the cement manufacturing plant.
  • a traditional kiln bypass the extracted kiln exhaust gases are cooled in a separate chamber by the application of air and/or water to a temperature which is lower than the condensation temperature of the volatile components, thereby allowing the volatile components to be separated in solid form from the exhaust gases, for subsequent disposal or application in the finished cement or for other purposes.
  • a plant of the kind mentioned in the introduction is characterized in that at least some of the means for removing volatile components from the plant are located after the calciner viewed in the direction of movement of the gases.
  • volatile components such as chloride, particularly KCI
  • the energy loss will be reduced since the gases after the calciner have a temperature which is lower than that occurring immediately after the kiln, and, therefore, there the volatile components need not to be cooled to the same extent in order to achieve condensation.
  • Another advantage of the plant according to the invention is that the draught conditions and the mixing ratio of the gases which are drawn through the calciner and the preheater will be far less disrupted.
  • the means which are located after the calciner viewed in the direction of movement of the gases for removing volatile components from the plant, and which in principle may comprise any appropriate means for this purpose, should preferably be located ahead of the location where preheated raw material from the preheater is introduced into the gases. This is due to the fact that the preheated material will lower the temperature of the gases, causing volatile components to undergo condensation on the preheated material and thereby reducing the amount of volatile components which can effectively be removed from the plant.
  • the means may comprise a condensation body which at a temperature which is lower than the condensation temperature of the volatile components is configured for being led into and away from the gases, so that volatile components when brought into contact with the condensation body will undergo condensation and be deposited on the body.
  • the condensation body may for example comprise one or several discs protruding partially into the gases and partially positioned outside the gases, and being configured for rotation about their centreline.
  • the means may advantageously comprise means for active cooling of the condensation body, said means may comprise means for cooling the surface of the condensation body by the application of air, water or another cooling medium, and/or cooling channels provided in the condensation body for circulation of cooling medium.
  • the means may comprise a bypass for extracting a portion of the gases being discharged from the calciner, a cooling device for cooling the extracted gases and a separation unit for separating the condensed volatile components and dust from the gases.
  • the plant comprises preferably a separation unit, such as a cyclone, which is located between the calciner and the mentioned bypass in order to minimize the amount of calcined raw material entrained in the extracted gas stream.
  • the separation unit may appropriately be constituted by the cyclone which at all cement manufacturing plants of the kind mentioned in the introduction is located after the calciner.
  • Fig. 1 shows a first embodiment of a cement manufacturing plant according to the invention
  • Fig. 2 shows a sectional view of a second embodiment of a cement manufacturing plant according to the invention.
  • Fig. 1 a plant for manufacturing cement clinker, which plant comprises a cyclone preheater 1 , a calciner 3 with separation cyclone 11 , a rotary kiln 5 and a clinker cooler 7.
  • Cement raw materials are introduced via an inlet F in the inlet duct to the uppermost cyclone stage of the cyclone preheater 1 , being preheated, calcined and burned into clinker by being transported first through the preheater 1 , the calciner 3, and then through the rotary kiln 5 in counter flow to hot exhaust gases which are formed at, respectively, a burner 8 in the rotary kiln 5 and a burner 9 in the calciner 3, and combustion air which is introduced to the calciner 3 via a duct 10, and being drawn through the preheater string 1 by the application of a not shown fan.
  • the burned clinker is subsequently cooled in the clinker cooler 7 by the application of cooling air.
  • the shown plant also comprises means
  • At least some of the means 12 for removing volatile components from the plant are located after the calciner 3 viewed in the direction of movement of the gases so that the relatively substantial amounts of volatile components which circulate in this part of the plant can thus be removed from the plant in a manner which is advantageous from the viewpoint of energy and operational efficiency, and thus coatings and clogging further upstream in the preheater can be avoid.
  • the means 12 are located ahead of the location 19 where preheated raw material from the preheater is introduced to the gases.
  • the means 12 comprise a bypass and they are located after the separation cyclone 11 of the calciner 3 in order to minimize the amount of calcined raw material entrained in the extracted gas stream.
  • the shown bypass comprises a mixing chamber 13 for extracting and cooling a portion of the gases from the calciner 3, a separation cyclone 14 for separating coarse solid particles from the cooled gases being diverted from the mixing chamber 13, said solid particles possibly being returned to the kiln 5, a conditioning tower 15 for additional cooling of the gases, a filter 16 for separating dust with a high content of chloride, alkali and/or sulphur, as well as a fan 17 for drawing the gases through the mentioned bypass.
  • the mixing chamber 13 comprises in the embodiment shown a tubular housing which is provided at one end with an inlet for gases from the calciner 3 and provided at its other end with an outlet for cooled gases.
  • the gases from the calciner 3 are cooled in the mixing chamber 13 using cooling gas which is introduced via a tangential inlet 18.
  • the means 12 are located ahead of the separation cyclone 11 of the calciner 3 and comprise a condensation body in the form of a disc 21 , which is fitted on a shaft 22, being capable of rotation through the use of appropriate means.
  • the disc 21 is located immediately after the calciner 3 in such a way that approximately one-third of the disc 21 projects into the gases in the discharge duct from the calciner 3 and so that approximately two-thirds of the disc 21 are located outside.
  • the disc 21 rotates in such a way that its coldest part is constantly introduced into the gases in the discharge duct from the calciner 3.
  • volatile components present in steam phase in the gases will, when brought into contact with the disc 21 , be cooled to a level below their condensation temperature so that they are condensed and deposited on the disc 21.
  • the hottest parts of the disc 21 are simultaneously moved out of the discharge duct and can subsequently be cleaned of deposited condensation products through the use of for example appropriate scraping elements.
  • the plant may further comprise means, not shown, for injecting water onto that part of the disc 21 which is located outside the discharge duct in order to obtain an enhanced cooling.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Thermal Sciences (AREA)
  • Public Health (AREA)
  • Toxicology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Health & Medical Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Cyclones (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Furnace Details (AREA)

Abstract

L'invention porte sur une installation pour la fabrication de ciment. Cette installation comprend un dispositif de préchauffage cyclone (1) pour préchauffer des matières premières de ciment, un four de calcination (3) pour la calcination de matières premières de ciment préchauffées, un four (5) de brûlage d'un clinker de ciment, ainsi que des moyens (12) pour éliminer les composants volatils, tels que des chlorures, les alcali et le soufre, à partir de l'installation de fabrication de ciment. L'installation est caractérisée par le fait qu'au moins certains des moyens (12) pour éliminer les composants volatils à partir de l'installation sont situés après le four de calcination (3) observé dans la direction du mouvement des gaz. Il est par là obtenu que des quantités significatives de composants volatils, tels que des chlorures, en particulier KCl, peuvent être éliminées de l'installation étant donné que l'élimination est effectuée à l'endroit dans l'installation où se trouve la concentration la plus élevée de ces composants, ce qui permet ainsi d'éviter des dépôts et un bouchage plus en amont dans le dispositif de préchauffage. Egalement, la perte d'énergie sera réduite étant donné que les gaz après le four de calcination ont une température qui est inférieure à celle se trouvant immédiatement après le four et, par conséquent, le ou les composants volatils n'ont pas besoin d'être autant refroidis pour parvenir à une condensation. Un autre avantage de l'installation selon l'invention est que les conditions de tirage et le rapport de mélange des gaz qui sont tirés à travers le four de calcination et le dispositif de préchauffage seront de loin moins perturbés.
PCT/EP2008/066005 2008-02-01 2008-11-21 Installation pour la fabrication de ciment Ceased WO2009095121A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DKPA200800141 2008-02-01
DK200800141A DK200800141A (da) 2008-02-01 2008-02-01 Anlæg til fremstilling af cement

Publications (1)

Publication Number Publication Date
WO2009095121A1 true WO2009095121A1 (fr) 2009-08-06

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DK (1) DK200800141A (fr)
WO (1) WO2009095121A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011135468A1 (fr) * 2010-04-29 2011-11-03 Flsmidth A/S Usine de fabrication de ciment
CN102575901A (zh) * 2009-10-07 2012-07-11 Fl史密斯公司 用于制造水泥的方法和设施
JP2013159534A (ja) * 2012-02-07 2013-08-19 Ube Industries Ltd セメント製造装置及び製造方法
US20160016113A1 (en) * 2013-04-01 2016-01-21 Fuel Tech, Inc. Reducing Hydrochloric Acid in Cement Kilns
EP3513885A1 (fr) * 2013-06-07 2019-07-24 Milli Spanovic Installation et procédure de traitement d'un solidificat

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102401573B (zh) * 2011-11-11 2013-08-21 大连易世达新能源发展股份有限公司 一种用于水泥窑旁路放风烟气余热发电的取风系统

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3291205A (en) * 1964-05-21 1966-12-13 American Cement Corp Apparatus for alkali metal condensation in cement kilns
EP0154281A2 (fr) * 1984-02-28 1985-09-11 Klöckner-Humboldt-Deutz Aktiengesellschaft Procédé et dispositif pour la fabrication de ciment
EP0927707A1 (fr) * 1997-07-17 1999-07-07 Taiheiyo Cement Corporation Procede et appareil de refroidissement des gaz d'echappement provenant d'une derivation d'un four

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3291205A (en) * 1964-05-21 1966-12-13 American Cement Corp Apparatus for alkali metal condensation in cement kilns
EP0154281A2 (fr) * 1984-02-28 1985-09-11 Klöckner-Humboldt-Deutz Aktiengesellschaft Procédé et dispositif pour la fabrication de ciment
EP0927707A1 (fr) * 1997-07-17 1999-07-07 Taiheiyo Cement Corporation Procede et appareil de refroidissement des gaz d'echappement provenant d'une derivation d'un four

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102575901A (zh) * 2009-10-07 2012-07-11 Fl史密斯公司 用于制造水泥的方法和设施
WO2011135468A1 (fr) * 2010-04-29 2011-11-03 Flsmidth A/S Usine de fabrication de ciment
JP2013159534A (ja) * 2012-02-07 2013-08-19 Ube Industries Ltd セメント製造装置及び製造方法
US20160016113A1 (en) * 2013-04-01 2016-01-21 Fuel Tech, Inc. Reducing Hydrochloric Acid in Cement Kilns
US9718025B2 (en) * 2013-04-01 2017-08-01 Fuel Tech, Inc. Reducing hydrochloric acid in cement kilns
EP3513885A1 (fr) * 2013-06-07 2019-07-24 Milli Spanovic Installation et procédure de traitement d'un solidificat

Also Published As

Publication number Publication date
DK200800141A (da) 2009-08-02

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