中文站        ENGLISH

Web Search: Goods

Your present location:Home >> NEWS >> Industry News >> Introduction to the protection of the rotary kiln calcining zone refractory brick

PROJECTS

Best-seller Products

CONTACT US

  +86 371 6697 7771
  +86 177 6166 6681
  +86 371 6977 7737
   sales@sijihuo.com  
Project details

Introduction to the protection of the rotary kiln calcining zone refractory brick

Number of visits: Date:9/1/2016

  Is to protect the main function of rotary kiln refractory brick kiln cylinder is not affected by high temperature gas and high temperature material damage, to ensure normal production.

  Is to protect the main function of rotary kiln refractory brick kiln cylinder is not affected by high temperature gas and high temperature material damage, to ensure normal production. In industrial production, the short service life of refractory brick, the firing often leads to an unplanned stop kiln maintenance, cement kiln is in high quality, high yield, low consumption and availability of the key factors.

  First, the erosion mechanism of refractory brick

  Wet method kiln, or NSP kiln in clinker calcining process, because the gas temperature is much higher than the material temperature, kiln every rotation kiln lining surface thermal shock by cyclical temperature range is 150 ~ 250 ℃, 10 ~ 20 mm in kiln lining surface within the scope of the thermal stress is produced. Kiln lining is due to the rotation of the kiln and brick masonry under variations of radial and axial mechanical stress, as well as the material of erosion wear. Due to generate silicate melt at the same time, under the environment of high temperature is easy to interact with kiln lining refractory brick surface form initial layer, and at the same time along the porosity of the refractory brick into the interior of the brick, and stick together, refractory surface layers of firebrick 10 ~ 20 mm within the scope of the chemical composition and phase composition change, reduce the technical performance of refractory brick. When material sintering range is relatively narrow or form a short flame eager produce local high temperature burning, can make the kiln surface minimum temperature is higher than the liquid solidification temperature of kiln skin surface layer that is, from solid to liquid, and go deep into the kiln and were situated in again after the initial form new kiln's initial layer. When this situation is repeated, calcining zone of kiln lining is gradually by the thick and thin, and even completely detached, lead to local show red kiln kiln cylinder. In fact the situation as it is, the kiln lining damage and the firing in the high temperature area residual brick thickness in general distribution of arc curvature radius is larger, sometimes arc bottom fall on the inner surface of the kiln simplified.

  Second, the protection of the refractory brick

  1. The influence of the physical properties of refractory brick

  Slag resistance refers to the ability of resistance to chemical attack, refractory in the formation of initial layer and kiln when viscous material or produce local high temperature prompted kiln skin fall off cases, slag resistance is very important.

  Porosity and the coefficient of thermal conductivity, the importance of initial layer to form a kiln, and local fall off in the kiln, porosity and coefficient of thermal conductivity larger help kiln refractory skin make up hang. But at the same time may have showed great damage, make the thin layer of refractory brick peel falls off.

  Refractory in the process of its production, its physical and chemical changes are generally not firing temperature balance. Also have insufficient burnt brick, and in the rotary kiln role again when subjected to high temperature, most of the refractory brick because of its generation and pore filling liquid itself, irreversible reheat shrinkage. As a result, high temperature stability, volume must be considered when choosing calcining zone refractory brick.

  Hot surface shape 勅 from calcining zone kiln is a rotary kiln lining subjected to heat the main form of earthquake damage; If local kiln skin peeling at the same time, will has greatly shortened the service life of refractory brick.

  2. The combustion and fuel nozzle effect on refractory brick

  Using coal as fuel, the volatile matter of coal and ash content plays a decisive role, directly affects the flame shape. High volatile and low ash content of coal powder, can make the black rotor shorten, form the long-flame calcined at low temperature. To protect the kiln lining is good, but high volatile, fire too fast, use kiln clinker temperature above 260 ℃, the secondary air temperature over 900 ℃, easy to burn out the nozzle, the deformation or burn appeared gap, come unstuck flame shape, damage before it is replacing the kiln lining. Volatile matter of coal are low (< 0%), the ash content is too high (> 28%), the incomplete combustion of pulverized coal subsidence combustion within the material and emits a large amount of heat will damage the kiln.

  Fuel nozzle structure often didn't get enough attention in the production, nozzle shape and export size main influence degree of the mixture of pulverized coal at the same time, the wind and the jet velocity, sometimes in order to strengthen the wind coal blending, but also within the nozzle with the wind wings, but must pay attention to the spiral wind flow too much rotating kiln skin injury.

  3. Raw material composition fluctuation effect on refractory brick

  When aluminum rate is too high, when the liquid viscosity big, kiln caving in great quantities, not easy to control on the operation, adverse to the protection of kiln lining, general control in the production practice of chinalco rate 1.3 ~ 1.6; When the quantitative high saturation ratio, rate of high silicon and low liquid ingredients are prone to sticky powder when flushing, serious injury when the kiln kiln thin skin abrasion kiln lining, silicon 2.5 production practice, the saturation ratio should not be more than 0.92, when a 2.8 silicon, saturation ratio should not be more than 0.90.

  Fluctuations in raw meal feeding rate of the harm of kiln lining is larger. When incoming too much when the stove is not none preheater, exhaust air of small strong force increase dosage of pulverized coal in the fire to burn, make the heat load increases rapidly, the firing kiln lining severely damaged. Material when the stove is too little, the pulverized coal flame downdip obviously, the area of the kiln at high temperatures will fall off, thinning, pouncing on thinner material layer, if not timely adjust the air flow and coal, easy to burn skin and refractory brick kiln. In addition, fluctuations in the raw meal feeding rate and can cause thermal unstable temperature ambassador kiln skin loss or damage.

  Through the above analysis, when the temperature of the clinker from the kiln is as high as 1260 ℃ above, the secondary air temperature exceeds 900 ℃, easy to burn out the nozzle, the deformation or burn appeared gap, come unstuck flame shape, make the kiln lining is easily damaged. Clinker values of three general control in KH0.91 plus or minus 0.01, silicon rate 2.6 + / - 0.1, aluminum rate control between 1.3 ~ 1.6, to protect the service life of refractory brick and improve clinker strength is extremely beneficial.

Previous post:

Next post:

TypeInfo: Industry News

Keywords for the information:

    

 

Tel : +86 371 6697 7771     Mob: +86 177 6166 6681
Email :   sales@sijihuo.com   

Address: Nanhuan Central Road, Xinmi City, Henan Province, China.

Fax : +86 371 6977 7737
 
Copyright ©   Zhengzhou Sijihuo  Refractory Co., Ltd.    
 
Message:
* Entered characters:0 Word
Less than or equal500Character
Email:
*
Verification: