General requirements for cement rotary kiln: Improve corrosion resistance, thermal shock stability and wear resistance.

① Improve corrosion resistance. Add silicon carbide, zirconium oxide, chromium oxide and aluminum-magnesium spinel, etc. to reduce pores.

②Improve thermal shock stability. Reasonably select the production process to make the pore distribution and strength help to relieve stress and prevent crack propagation.

③Improve wear resistance. Choose materials with medium and high temperature thermal strength to reduce the critical particle size of the material.

④ Change the construction method. Use self-flowing castables, spray coatings, explosion-proof castables and thermosetting materials.

Improve stress resistance, increase high temperature strength, increase thermal insulation performance, composite bricks, thermal insulation materials, scientific and reasonable brick shapes, accurate brick dimensions, and brick masonry.

Expansion joints reserved: Correct use of fire mud and cardboard, brick use, baking, cooling, hanging kiln skin, maintenance of kiln skin, etc.

1. Magnesium-iron-aluminum spinel brick raw materials: high-purity magnesia and iron-aluminum spinel; process: reasonable gradation, high-pressure forming, strict control of the firing temperature and firing atmosphere; characteristics: good flexibility and thermal shock stability Good performance, good volume stability at high temperature, high softening temperature, excellent kiln-hanging performance.
          2. Magnesia-calcium bricks Magnesium-calcium bricks are alkaline refractory materials made of calcined magnesia-calcium sand, usually with a CaO content of more than 40%, and are mainly used in the burning zone of rotary kilns. Reasons for easy sticking of kiln skin: ① At 1450℃, C2S in the clinker (melting point 1900℃) chemically reacts with CaO in the brick, forming C3S (melting point 2130℃) at the brick interface, forming a strong and stable kiln skin; ② CaO The reaction with the clinker increases the viscosity of the melt, and the clinker melt is difficult to penetrate into the interior of the bricks, thereby reducing the corrosion and peeling of the bricks and stabilizing the kiln skin; The load and chemical erosion are reduced, and the heat loss from the kiln wall is reduced. Question: How to solve the hydration problem during production, storage and use.
   
          3. Magnesia-zirconia bricks are made of fused magnesia and zircon sand as the main raw materials through high-pressure forming and high-temperature firing. Dense structure, small pores and uniform distribution, high-temperature strength, good thermal shock stability, alkali corrosion resistance and excellent kiln skin performance, suitable for the firing zone of cement rotary kilns.
   
          4. Magnesia-aluminum spinel bricks use high-purity magnesia and synthetic magnesia-aluminum spinel as the main raw materials. The main crystal phases are periclase and spinel, which have good corrosion resistance, spalling resistance and high temperature resistance. They can be used The transition zone of a large dry-process cement rotary kiln.
   
           5. Silicon-mold wear-resistant bricks are made of high-grade high-alumina bauxite clinker, silicon carbide and metallic silicon as main raw materials, through high-pressure forming and high-temperature firing. High strength at room temperature and high temperature, good thermal shock stability, continuous formation of protective layer during use, good wear resistance and strong peeling resistance, suitable for the lower transition zone, cooling zone, kiln mouth and other parts of cement kilns.
   
            6. Anti-stripping high alumina bricks Take super high alumina bauxite clinker as the main raw material and add phase change materials such as zircon sand, kyanite, andalusite to improve its thermal shock resistance stability. It has strong anti-stripping ability, anti-corrosion of potassium, sodium, sulfur, chlorine and alkaline salt, low thermal conductivity, etc. It is an ideal material for cement kiln transition zone and decomposition zone. It can also be used for cement kiln door cover and cooling Machine and other parts.
   
            7. Alkali-resistant bricks, alkali-resistant castables, steel fiber reinforced refractory castables ①Alkali-resistant bricks: Alkali-resistant bricks are made of low-aluminum refractory clay, silica, scorched gemstones, waste porcelain and appropriate additives as the main raw materials. The product has the characteristics of stable volume, strong alkali corrosion resistance and penetration resistance. Used in preheaters, decomposition furnaces, tertiary air ducts and other parts of cement kilns. ②Alkali-resistant castable: Alkali-resistant castable is a castable prepared with alumina silicate material as refractory aggregate and powder, aluminate cement and additives. It has good high temperature performance and alkali corrosion resistance. The high-strength type also has high strength and good wear resistance. It can be used in large and medium-sized dry-process cement kiln preheaters and air ducts. ③Steel fiber reinforced refractory castable: high bauxite clinker or corundum as aggregate and powder, adding binder and appropriate amount of heat-resistant stainless steel fiber has high strength, good toughness, good thermal shock stability, and anti-stripping And the characteristics of strong wear resistance. Suitable for cement rotary kiln kiln mouth, cooler, decomposition furnace, preheater and other parts.
   
            8. Special castables for kiln mouth and coal injection pipes use andalusite, silicon carbide, corundum, high-quality bauxite, α-Al2O3 and SiO2 micropowder as main raw materials, use CA-71 cement as binder and add superplasticizer and other additives , It has good thermal shock resistance, corrosion resistance, alkali resistance and high temperature volume stability. It is used for cement rotary kiln mouth.