Classifications

• • 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
  • C04B7/361—Condition or time responsive control in hydraulic cement manufacturing processes
• • 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
  • C04B7/364—Avoiding environmental pollution during cement-manufacturing
• • 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
  • C04B7/4476—Selection of the kiln atmosphere
• • 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
  • F27B7/10—Rotary-drum furnaces, i.e. horizontal or slightly inclined internally heated, e.g. by means of passages in the wall
• • 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
  • F27B7/2016—Arrangements of preheating devices for the charge
  • F27B7/2025—Arrangements of preheating devices for the charge consisting of a single string of cyclones
  • F27B7/2033—Arrangements of preheating devices for the charge consisting of a single string of cyclones with means for precalcining the raw material
• • 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
  • F27B7/2016—Arrangements of preheating devices for the charge
  • F27B7/2041—Arrangements of preheating devices for the charge consisting of at least two strings of cyclones with two different admissions of raw material
• • 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

Definitions

• the invention relates to a cement plant and a method for operating a cement plant.
• the raw material In cement clinker production, the raw material is first preheated, then precalcined and finally fired in an oven. The actual firing process takes place in the sintering zone of the furnace, in which the material is heated to temperatures of 1400 to 1500 0 C.
• DE 698 06 182 relates to a process for the production of cement clinker by means of sulfur-rich fuel, wherein the oxygen concentration at the inlet of the kiln is increased to 4.5 to 5.5%, whereby the temperature at which the calcium sulfate decomposes to a temperature greater than the sintering temperature, so that CaSO 4 becomes a constituent of the final product instead of decomposing into gases and leaving behind deposits in the kiln, preheat and preheat cyclones.
• Furnace exhaust discharged (volatility).
• the kiln exhaust gas is used to heat treat the material in the calcining zone and preheating zone. During this heat exchange, the volatiles condense on the raw material (adsorption) and are reintroduced into the sintering zone. There they partially dissipate again, so that in this way a cycle of this
• EP-A2-1 428 804 discloses a cement clinker to be produced with fuel having a sulfur concentration of more than 5%, the specification does not specify how this cement clinker can be produced without it thereby to formations in the preheater or
• the invention is therefore based on the object of specifying a method and a device for operating a cement plant, wherein fuel with a high sulfur content can be used without the SO 2 -
• the raw meal is preheated in a preheating zone, the preheated material in a
• Calcining zone precalcined and the precalcined material finally in a
• Sintered sintered zone The cement plant is operated in such a way that the
• Sintered zone fed precalcined material having a S O3 concentration of at least 5.5 mass percent and a CaSO4 content of at least 75 mass%, preferably 90%, of the total salt content of the precalcined material.
• the cement plant according to the invention has a preheating zone for preheating the raw material, a calcining zone for precalcining the preheated material and a sintering zone for sintering the precalcined material. Furthermore, a control and regulating device for operating the cement plant according to the above method is provided.
• the invention is based on the recognition that the formation of deposits depends not only on the sulfur concentration but also on the salt composition and in particular on the CaSO 4 content. With a correspondingly high CaSO 4 content, therefore, the SO 3 concentration can be raised significantly above the previously tolerable level. With a CaSO 4 content of 90% by mass of the total salt content, the SO 3 concentration can be increased to more than 10% by mass.
• Material can be influenced by one or more of the following measures:
• a. Selection of raw materials b. Selection of the fuel used in the sintering zone, c. Adjustment of the momentum of a burner operating in the sintering zone, d. Adjusting the ratio of combustion air and fuel in the sintering zone, e. Adjusting the ratio of fuel quantity and raw meal amount at at least one fuel supply point of the plant, f. Adjustment of the precalcination degree of the raw meal after the calcination zone, g. Setting the raw meal fineness.
• the cement plant is expediently operated so that the volatility of sulfur in the sintering zone is at least 60%, preferably at least 80% and the sulfur adsorption in the preheater zone, in the calcining zone and / or in the sintering zone at least 80%, preferably at least 90%.
• the exhaust gas leaving the preheater should have an SO 2 content of less than 600 mg / Nm 3 at 10% O 2 , preferably less than 300 mg / Nm 3 at 10% O 2 . This is achieved by increasing the adsorption in the context of the set volatility.
• Fig. 1 is a representation of the interaction of SO 3 and Cl on approach in the inlet of the rotary kiln and
• Fig. 2 drawing shows a schematic representation of a cement plant.
• the cement plant according to FIG. 2 essentially consists of a preheating zone 1, for example a multi-stage suspension gas heat exchanger, a calcining zone 2 and a sintering zone 3 designed as a rotary kiln and a downstream cooling zone 4, which is formed for example as a sliding grate cooler.
• the exhaust gases of the sintering zone 3 flow successively through the calcining zone 2 and the preheating zone 1, the raw meal is added in a manner known per se countercurrent to the exhaust gases of the preheating zone 1 and then the calcining zone 2, before the precalcined material is fired in the sintering zone 3 ,
• the sintering zone has at least one burner 5 with adjustable momentum.
• the sintering zone 3 is operated with a burner with adjustable momentum, so that by adjusting the momentum, the flame shape, size and / or - temperature can be adjusted.
• the calcining zone 2 is formed in the illustrated embodiment by a riser, which is connected via a manifold to the lowermost cyclone Ia of the preheating zone.
• a riser which is connected via a manifold to the lowermost cyclone Ia of the preheating zone.
• at least one raw meal conduit 8 opens into the preheating zone 1 in the calcining zone 2.
• Fuel, combustion air and raw meal can be introduced into the calcining zone at one or more points arranged one above the other.
• system comprises suitable means for performing at least one of the following operating parameter measurements:
• the adsorption conditions can be adjusted: More oxygen means more adsorption and thus a higher SC ⁇ content in precalcined material and less SO 2 im exhaust chimney.
• the cement plant is operated so that the precalcined material fed to the sintering zone has a SO 3 concentration of at least 5.5 mass% and a CaSO 4 content of at least 75 mass%, preferably at least 90% of the total salt content.
• the SO 3 concentration and the CaSO 4 content in the precalcined material can be influenced by the following measures:
• Sintering zone e. Adjustment of the ratio of fuel quantity and raw meal amount at least one fuel supply point of the system, f. Adjustment of the precalcination degree of the raw meal after the calcination zone, g. Setting the raw meal fineness.
• the S O3 concentration and the CaS04 content can still be decisively influenced by the measures c to f.
• these measures can influence the volatility of sulfur in the sintering zone in the region of the sintering zone. In this case, a volatility of at least 60%, preferably more than 80%, is desirable.
• Another very important mechanism for the operation of the cement plant is sulfur adsorption in the preheating zone 1, in the calcining zone 2 and / or in the
• the adsorption in the calcination zone is based on the following reaction: CaO + SO 2 + 1 AO 2 -> CaSO 4
• Air supply 7 in the calcining zone is usually tertiary air from the cooling zone, which could possibly still be enriched with pure oxygen.
• Adjustment of the ratio between combustion air and fuel quantity influences the oxygen concentration in the calcination zone as well as the volatility of the sulfur.
• a fuel with a sulfur concentration of at least 3.5% by mass can be used in the sintering zone and optionally in the calcining zone. If the plant is operated in such a way that the precalcined material fed to the sintering zone has an S O3 concentration of at least 5.5% by mass and a CaSO 4 content of at least 75% by mass of the total salt content, it can be achieved that despite the high sulfur input in the
• the exhaust gas leaving the preheater has an SO 2 content of less than 600 mg / Nm 3 at 10% O 2 , preferably less than 300 mg / Nm 3 at 10% O 2 ), the reliability of the system is guaranteed and approaches and blockages are avoided.
• the cement clinker fired in the sintering zone then has an SO 3 concentration of at least 1% by mass, preferably at least 2% by mass.
• a device for interrupting the circuits such as a bypass device, are installed, by their operation and the changes in the deposited dust and / or gas quantities, the circuits, in particular sulfur, alkalis and / or chlorine, influenced and adjusted accordingly.
• the circuits in particular sulfur, alkalis and / or chlorine, influenced and adjusted accordingly.
• several air blast equipment in certain areas of the preheater and / or calciner can be installed to improve the cleaning in the danger zones and to increase the reliability.
• the cement plant can be operated safely and with low S ⁇ 2 emissions.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Ceramic Engineering (AREA)
• Materials Engineering (AREA)
• Structural Engineering (AREA)
• Organic Chemistry (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Environmental & Geological Engineering (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Health & Medical Sciences (AREA)
• Biodiversity & Conservation Biology (AREA)
• Ecology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Environmental Sciences (AREA)
• Public Health (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)
• Furnace Details (AREA)
• Muffle Furnaces And Rotary Kilns (AREA)
• Manufacture And Refinement Of Metals (AREA)
• Fertilizers (AREA)
• Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)

Priority Applications (11)

Applications Claiming Priority (2)

Publications (1)

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Citations (8)

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• 2008
  • 2008-08-04 DE DE102008036088A patent/DE102008036088B4/de not_active Expired - Fee Related
• 2009
  • 2009-07-28 ES ES09781203T patent/ES2385291T3/es active Active
  • 2009-07-28 WO PCT/EP2009/059758 patent/WO2010015551A1/de not_active Ceased
  • 2009-07-28 AT AT09781203T patent/ATE556992T1/de active
  • 2009-07-28 CA CA2731483A patent/CA2731483C/en not_active Expired - Fee Related
  • 2009-07-28 CN CN200980130975.3A patent/CN102149650B/zh not_active Expired - Fee Related
  • 2009-07-28 US US13/054,947 patent/US8764438B2/en active Active
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  • 2009-07-28 DK DK09781203.6T patent/DK2310333T3/da active
  • 2009-07-28 RU RU2011108265/03A patent/RU2503630C2/ru active
  • 2009-07-28 JP JP2011521531A patent/JP5615818B2/ja not_active Expired - Fee Related
  • 2009-07-28 MX MX2011001214A patent/MX2011001214A/es active IP Right Grant
  • 2009-07-28 EP EP09781203A patent/EP2310333B1/de not_active Not-in-force

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