Phosphate bonded castable adopting composite hardening accelerator

Abstract

The invention relates to a phosphate bonded castable adopting a composite hardening accelerator, belonging to the technical field of refractory materials. The phosphate bonded castable is prepared from the following main raw materials in percentage by mass: 55-75wt% of aggregate, 9-40wt% of powder material, 5-16wt% of composite hardening accelerator, 0.1-0.25wt% of corrosive inhibitor and 8-18wt% of bonding agent, wherein the aggregate is corundum or high-aluminum bauxite; the powder material comprises 0-37wt% of corundum powder, 0-37wt% of bauxite powder, 1-8wt% of SiO2 micropowder and 3-12wt% of alpha-Al2O3 micropowder; the composite hardening accelerator is pure calcium aluminate cement and rho-Al2O3 micropowder; the corrosive inhibitor is an NH66 type inhibitor, and comprises the main chemical component of bismuth oxyiodotannate; and the bonding agent is phosphate (aluminum phosphate solution), and the P2O5/Al2O3 ratio is 1/2.5-1/3.8. The phosphate bonded castable has the advantages of high strength, wear resistance, thermal shock resistance, short stripping time, capability of being quickly baked and the like, and has excellent high-temperature resistance.

Description

technical field [0001] The invention relates to the field of refractory materials, in particular to a phosphate-bonded castable using a composite hardening accelerator. Background technique [0002] Phosphate-bonded castables have excellent properties such as good thermal shock stability, high compressive strength, wear resistance, and erosion resistance, and are widely used as lining materials for various thermal kilns. [0003] However, the hardening accelerators used in commonly used phosphate-bonded castables are mainly high-alumina cement and MgO fine powder. When high-alumina cement is used as hardening accelerator, the introduction of CaO reduces the high-temperature performance of the material; When used as a hardening accelerator, the construction process is complicated and difficult due to the rapid reaction between MgO fine powder and phosphate. At the same time, due to the introduction of some metallic iron in the raw material and the crushing process of the raw...

AI Technical Summary

Problems solved by technology

[0003] However, the hardening accelerators used in commonly used phosphate-bonded castables are mainly high-alumina cement and MgO fine powder. When high-alumina cement is used as hardening accelerator, the introduction of CaO reduces the high-temperature performance of the material; When used as a hardening accelerator, due to the rapid reaction between MgO fine powder and phosphate, the construction process is complicated and difficult

At the same time, due to the neutralization of raw materials and the introduction of some metallic iron during the crushing process, the currently commonly used phosphate-bonded castables need to be trapped in use, which brings troubles to construction

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