Coal-injection duct self-flowing castable

Abstract

The invention relates to a coal-injection duct self-flowing castable. The coal-injection duct self-flowing castable comprises the following components in parts by weight: 18-25 parts of 8-5 mm of sintered mullite, 15-20 parts of 5-3 mm of sintered mullite, 5-10 parts of 3-1 mm of sintered mullite, 12-18 parts of 1-0 mm of sintered mullite, 5-10 parts of 1-0 mm of pink fused alumina, 6-10 parts ofpink fused alumina powder less than 200 meshes, 6-10 parts of aluminum oxide powder, 4-8 parts of calcium aluminate cement, 3-8 parts of silica powder, 3-6 parts of melted quartz powder, 1-3 parts ofchromic oxide powder, 0.01-0.03 parts of anti-explosion fibers, and 0.01-0.03 parts of a water reducing agent. The coal-injection duct self-flowing castable is capable of, through grain gradation andadjustment of a material system, realizing the self-flowing effect of the coal-injection duct castable, changing a traditional vibration construction mode of a coal-injection duct, and flowing, leveling, compacting and solidifying by using a self-flowing mode, less in water addition during a construction process, and strong in flowability.

Description

technical field [0001] The invention belongs to the technical field of refractory materials, and in particular relates to a self-flow castable for coal injection pipes. Background technique [0002] In the modern new dry-process cement production line, the system equipment is continuously enlarged, the output of cement clinker is doubled, the load on the refractory materials used in the system is also increasing, and the service conditions are becoming more and more harsh. Only high-performance refractory Materials can guarantee the normal operation of production equipment. The castable of the coal injection pipe is subjected to severe erosion by high-temperature dust-laden airflow, and the temperature of this part changes drastically, and the concentration of alkali vapor in the gas is relatively high. The castable is prone to cracking and peeling, resulting in a serious decline in service life. Coal injection pipe not only plays an important role in optimizing kiln operat...

AI Technical Summary

Problems solved by technology

Moreover, the shape of the coal injection pipe determines that the pouring construction process is difficult, and it is difficult to fully vibrate and compact. In order to ensure that the material can be fully filled in a narrow space, it is often necessary to add more water, which directly results in the reduction of material strength and service life. severely affected

[0003] In the prior art, the castables disclosed in patents CN103553667A, CN104355645B, and CN102584295B all use silicon carbide as a raw material. Although silicon carbide has the characteristics of good thermal shock resistance, it is prone to oxidation under the oxidizing atmosphere used in the coal injection pipe. Thus affecting the service life of the castable

The casting material disclosed in patent CN101514109B does not contain silicon carbide, and spinel is used as the main material to prepare coal injection pipe pouring and has achieved certain results. However, compared with mullite, spinel has a larger thermal expansion coefficient, so it is resistant In terms of thermal shock performance, there is still a certain gap with the coal injection pipe castable made of mullite material

Patent CN104108941B uses corundum mullite to prepare coal injection pipe castables. The bulk density of this castable increases the overall weight of coal injection pipes, and it is easy to cause bending deformation of coal injection pipes under high temperature conditions.

In addition, due to factors such as particle gradation and material system, most of the castables currently used for coal injection pipes are difficult to achieve self-flowing effects during construction and application, and must be compacted by external force.

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