Corundum mullite rock wear-resistant refractory castable

A refractory castable, mullite technology, applied in the field of refractory materials, can solve the problems of low medium temperature strength, thermal shock resistance and erosion resistance, high cost, and rarely used

Inactive Publication Date: 2009-11-04
贵阳明通炉料有限公司
View PDF0 Cites 28 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] As we all know, the temperature of the circulating fluidized bed boiler changes greatly, the dusty gas scours the furnace violently, and the furnace is easy to wear
At present, the unshaped refractory materials used to repair the furnace mainly include high-alumina wear-resistant refractory castables, corundum mullite wear-resistant castables, etc.; the former uses high-alumina bauxite clinker with a certain particle size as aggregate , with silica powder and high-alumina cement as a binder, its advantage is that the cost is low; but because the high-alumina bauxite clinker contains more impurities, a certain amount of high-alumina cement is added to the ingredients at the same time. When used at medium temperature, anorthite and calcium aluminum feldspar with low melting point and performance will be formed, resulting in poor strength, thermal shock resistance and erosion resistance of the castable when used at medium temperature, making the circulating fluidized bed boiler shorter lifespan
The latter is made of high alumina bauxite clinker, corundum, and mullite as the main raw materials, and is prepared by adding an appropriate amount of high alumina cement or pure calcium aluminate cement as a binder; due to the addition of corundum, mullite Stone components, so it can effectively improve the thermal shock resistance and erosion resistance of the castable. At present, this kind of castable is widely used in actual engineering; but because the binder is still high alumina cement or pure calcium aluminate cement, medium temperature There are still some defects in the strength is not high, thermal shock resistance and erosion resistance
Therefore, how to improve the medium-temperature strength of castables, how to improve thermal shock resistance and erosion resistance has become a serious issue for refractory manufacturers at home and abroad; for this reason, some companies completely use corundum and molybdenum Corundum mullite wear-resistant castables are prepared by using pure calcium aluminate cement as the raw material and the binder. Because the raw material has less impurities, it can effectively improve the medium temperature strength, thermal shock resistance and erosion resistance of the castable. , but due to the high cost, it is rarely used in practical engineering

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] 1) Take 75 kilograms of industrial aluminum hydroxide fine powder, 167.5 kilograms of phosphoric acid with a concentration of 45%, and 7.5 kilograms of chromium oxide green micropowder, mix evenly, slowly heat to 100 ° C, keep warm for 60 minutes, and make 250 kilograms of binding agent for subsequent use;

[0036] 2) Take 300 kilograms of white corundum powder, 125 kilograms of activated alumina micropowder, 25 kilograms of silicon micropowder, 40 kilograms of sodium tripolyphosphate, and 10 kilograms of sodium borate, mix them evenly, and grind together for 30 minutes to make 500 kilograms of additives for later use; among them, white corundum The physical and chemical indicators of fine powder, activated alumina micropowder and silica micropowder are as follows:

[0037] Table 4: White corundum fine powder

[0038] project

Al 2 o 3

Fe 2 o 3

oxide impurities

Refractoriness

Bulk density

White corundum fine powder

>99% ...

Embodiment 2

[0052] Each step is with embodiment 1; Wherein:

[0053] The binder in step 1) is prepared from 50 kg of industrial aluminum hydroxide fine powder, 197.5 kg of phosphoric acid, and 2.5 kg of chromium oxide green micropowder, heated to 90°C and kept for 30 minutes;

[0054] The additive in step 2) is prepared from 380 kilograms of white corundum powder, 75 kilograms of activated alumina micropowder, 25 kilograms of silicon micropowder, 15 kilograms of sodium tripolyphosphate, and 5 kilograms of sodium borate, which were milled together for 20 minutes;

[0055] The wet mud in step 3) is prepared from 150 kilograms of coarse-grained aggregate, 100 kilograms of medium-grained aggregate, 150 kilograms of fine-grained aggregate, 100 kilograms of binder, and 500 kilograms of additive;

[0056] The product of the present invention in step 4) is made from 960 kg of wet mud, 20 kg of calcium aluminate cement, and 20 kg of binder.

Embodiment 3

[0058] Each step is with embodiment 1; Wherein:

[0059] The binder in step 1) is prepared from 62.5 kg of industrial aluminum hydroxide fine powder, 182.5 kg of phosphoric acid, and 5 kg of chromium oxide green micropowder, heated to 100° C. and kept for 40 minutes;

[0060] Additives in step 2) are prepared from 330 kilograms of white corundum powder, 75 kilograms of activated alumina micropowder, 75 kilograms of silicon micropowder, 15 kilograms of sodium tripolyphosphate, and 5 kilograms of sodium borate, and are milled together for 25 minutes;

[0061] The wet mud in step 3) is prepared from 300 kg of coarse aggregate, 100 kg of medium aggregate, 150 kg of fine aggregate, 150 kg of binder, and 300 kg of additive;

[0062] The product of the present invention in step 4) is made from 925 kg of wet mud, 40 kg of calcium aluminate cement, and 35 kg of binder.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
particle sizeaaaaaaaaaa
particle sizeaaaaaaaaaa
particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a corundum mullite rock wear-resistant refractory castable which belongs to refractory materials, aiming at providing an unshaped refractory material with high medium temperature strength and good thermal shock resistance and erosion and wear resistance. According to weight percentages, the invention is formed by evenly mixing 89-96% of wet pug, 2-6% of calcium aluminate cement and 2-5% of bonding agent; the bonding agent is prepared by 20-30% of industrial aluminum hydroxide fine powder, 67-79% of phosphoric acid with concentration being 45% and 1-3% of chromium oxide green fine powder; the wet pug is prepared by taking corundum with certain particle grading or mixture of corundum and mullite as aggregate and adding the bonding agent and additive, the additive is prepared by 60-76% of white alundum powder, 15-25% of activated alumina fine powder, 5-15% of silicon fine powder, 3-8% of sodiumtripolypolyphosphate and 1-8% of sodium borate. The invention is mainly used as an ideal refractory castable for circulating fluid bed boiler lining and cement kiln lining.

Description

Technical field: [0001] The invention relates to a refractory material, in particular to an unshaped refractory material. Background technique: [0002] As we all know, the temperature of the circulating fluidized bed boiler changes greatly, the dusty gas scours the furnace violently, and the furnace is easy to wear. At present, the unshaped refractory materials used to repair the furnace mainly include high-alumina wear-resistant refractory castables, corundum mullite wear-resistant castables, etc.; the former uses high-alumina bauxite clinker with a certain particle size as aggregate , with silica powder and high-alumina cement as a binder, its advantage is that the cost is low; but because the high-alumina bauxite clinker contains more impurities, a certain amount of high-alumina cement is added to the ingredients at the same time. When used at medium temperature, anorthite and calcium aluminum feldspar with low melting point and performance will be formed, resulting in ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C04B35/66
Inventor 陈前林申青龙周志强吴锡培李文松李宗祥
Owner 贵阳明通炉料有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products