Refractory concrete made with aluminate cement as a binder, its composition, material ratio and scope of use:
1. Alumina cement refractory concrete
(1) Binder: Alumina cement with a size of 625 or more, with a mixing ratio of 15% to 20%.
(2) Aggregate: made of waste high-alumina bricks and waste clay bricks of secondary and tertiary bauxite clinker or primary and secondary clay clinker.
The particle size of the fine aggregate is less than 5mm; the mixing ratio is 30% to 40%.
Coarse aggregate particle size is 5 ~ 15mm; blending ratio is 30% ~ 40%.
(3) Powder (admixture): same as aggregate, with a particle size of less than 0.088mm, not less than 70%; the mix ratio is 0-15%.
The characteristics and application scope of bauxite cement refractory concrete are high strength at room temperature, wide source of materials, and convenient construction. It is suitable for the refractory layer of various parts of the boiler.
2. Portland cement refractory concrete
(1) Binder: Portland cement with a size of 42.5 or more.
(2) Aggregate: made of first- and second-grade clay clinker or waste bricks.
The particle size of the fine aggregate is less than 5mm; the mixing ratio is 35% to 40%.
Coarse aggregate particle size is 5 ~ 15mm; mix ratio is 30% ~ 40%.
(3) Powder: same as aggregate. No less than 70% of the particle size is less than 0.088mm; its mixing ratio is ≤15%.
The characteristics and application scope of Portland cement concrete are low prices and convenient construction. It is suitable for the refractory layer of various parts of the boiler.
3. Slag cement refractory concrete
(1) Binder: Slag cement with a size of 42.5 or more, and its mixing ratio is 16% to 20%.
(2) Aggregate: secondary or tertiary clay clinker or waste refractory brick.
The particle size of the fine aggregate is less than 5mm; the mixing ratio is 35% to 40%.
Coarse aggregate particle size is 5 ~ 15mm; mix ratio is 40% -45%.
(3) Powder:
The characteristics and application range of this kind of refractory concrete are low price, wide source of materials, and convenient construction. It is suitable for the refractory layer of the low-temperature part of the boiler.
4. Low calcium aluminate cement refractory concrete
(1) Binder: Low calcium aluminate cement with a size above 42.5, and its mixing ratio is 12% to 20%.
(2) Aggregate: Made of secondary or tertiary bauxite clinker or waste high alumina brick.
Fine aggregate, whose particle size is less than 5mm; the mixing ratio is 30% to 40%.
Coarse aggregate: particle size is 5 ~ 15mm; mix ratio is 30% ~ 40%.
(3) Powder: The same as aggregate, with a particle size of less than 0.088mm, not less than 70%, and its mixing ratio is 0-15%.
This kind of refractory concrete has higher refractory waste than alumina cement concrete. Besides being applicable to the refractory layer of various parts of the boiler, it can also be used for burner nozzles.
5. Heat-resistant cement refractory concrete
(1) Binder: refractory cement above 625, with a blending ratio of 25% to 30%.
(2) Aggregate: made of first- and second-grade clay clinker or waste clay bricks.
Fine aggregate, the particles are less than 5mm; the mixing ratio is 35% -40%.
Coarse aggregate, grain size is 5 ~ 15mm; mix ratio is 30% ~ 40%.
(3) Powder: Not necessary.
This kind of refractory concrete is easy to construct. It is suitable for the layer of various parts of the boiler.
The water-cement ratio of the above five kinds of concrete should be 0.35 to 0.45.