CN102219530A - Silicon mullite brick and preparation method thereof - Google Patents
Silicon mullite brick and preparation method thereof Download PDFInfo
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- CN102219530A CN102219530A CN2011100597748A CN201110059774A CN102219530A CN 102219530 A CN102219530 A CN 102219530A CN 2011100597748 A CN2011100597748 A CN 2011100597748A CN 201110059774 A CN201110059774 A CN 201110059774A CN 102219530 A CN102219530 A CN 102219530A
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Abstract
The invention discloses a silicon mullite brick and a preparation method thereof. The silicon mullite brick comprises the following raw materials in parts by mass: 75-90 parts of special-grade alumina, 10-18 parts of silicon metal powder, and 2-6 parts of paper pulp waste liquid. The method for preparing the silicon mullite brick comprises the steps of mixing and pressing the raw materials, gradually increasing temperature in a nitrogen environment, firing and the like. In the invention, by overcoming technological prejudices, silicon metal is used as the common silicon mullite brick raw material instead of silicon carbide; the common binding clay for producing fire-proof materials is unused; therefore, the product is subjected to a chemical reaction at 1100-1300 degrees centigrade; the energy consumption is reduced; high-density silicon nitride is generated in the nitrogen environment; the physiochemical performance is improved; simultaneously, because of not using the binding clay, compared with the original aluminium silicon carbide brick, the silicon mullite brick has greatly-increased refractoriness; furthermore, the process disclosed by the invention is simpler and can be realized easily; the production cost is greatly reduced; and the method is advantageous for being popularized in a large scale.
Description
Technical field
The present invention relates to brick body that a kind of refractory materials makes and preparation method thereof, be specifically related to a kind of non-pottery of cement rotary kiln that is used in conjunction with siliceous mullite brick and preparation method thereof.
Background technology
At present, the brick body that refractory materials is made is used widely in Industrial Stoves, and as the refractory lining layer of building materials industry large-scale cement rotary kiln, its refractory materials that adopts is an aluminum silicon carbide brick.Existing aluminum silicon carbide brick adopts pottery to form in conjunction with sintering mostly, and this series products firing temperature must reach and could form ceramic combination about 1420 ℃, owing in the time of 1350 ℃, can form the mullite phase, thereby cause the bodily form to expand, cause the difficult control of product design size, run into a lot of difficulties in process of production.In addition, ceramic junction credit union causes product strength low, and wear resistance descends, and makes furnace service life descend, and cost rises.For this reason, improve the wear resistance of the brick body that refractory materials makes and improve the product resistance to elevated temperatures, the scientific and technical personnel's that become this area of reducing production costs simultaneously research topic.
Summary of the invention
Goal of the invention:, the invention provides the high-quality siliceous mullite brick of a kind of high strength, high abrasion, heat-resisting shake in order to overcome the deficiencies in the prior art; Simultaneously, the present invention also provides the preparation method of this siliceous mullite brick, and this preparation method's technology is simple, is easy to realize, and is with low cost.
Technical scheme: for achieving the above object, siliceous mullite brick of the present invention comprises high grade bauxite, metallic silicon power and spent pulping liquor, and described high grade bauxite is for aluminium content is 88～90%, volume density is 3.25～3.35g/cm
3Alumina; Described metallic silicon power is 97～99% silica flour for Pure Silicon Metal content; The density of described spent pulping liquor is 1.1～1.35g/cm
3The content of described high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 75～90 parts, 10～18 parts, 2～6 parts.
As preferably, described high grade bauxite is for aluminium content is 88%, volume density is 3.25g/cm
3Alumina; Described metallic silicon power is 97% silica flour for Pure Silicon Metal content; The density of described spent pulping liquor is 1.25g/cm
3The content of described high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 80～90 parts, 10～15 parts, 4～6 parts.
The preparation method of siliceous mullite brick of the present invention may further comprise the steps: (1) takes by weighing according to composition of raw materials and respectively organizes raw material:
According to mass fraction, raw material comprises 75～90 parts of high grade bauxite, 10～18 parts of metallic silicon powers, 2～6 parts of spent pulping liquors, and described high grade bauxite is for aluminium content is 88～90%, volume density is 3.25～3.35g/cm
3Alumina; Described metallic silicon power is that Pure Silicon Metal is 97～99% silica flour; The density of described spent pulping liquor is 1.1～1.35g/cm
3(2) each group raw material is put into mixer respectively and mix, continue 10～30 minutes; (3) mixed raw material is put into the pressing machine die cavity and suppress, make work in-process; (4) work in-process that suppress are put into kiln and fire, under nitrogen environment, be incubated 2.5～3.5 hours after rising to 1100 ℃～1300 ℃ with 3～15 ℃ heat-up rate per hour; (5) take out siliceous mullite brick in the kiln, be cooled to room temperature after, promptly get described siliceous mullite brick; Then it is tested, and the packing warehouse-in.
In the step (3), described half-finished volume density is 2.7g/cm
3In the step (4), chemical reaction takes place in work in-process in the time of 1100 ℃～1300 ℃, and generates high fine and close silicon nitride under nitrogen environment, thereby improves its physicochemical property.
Beneficial effect: the present invention is by overcoming technology prejudice, make siliceous mullite brick raw material silicon carbide commonly used into Pure Silicon Metal, and refractory materials bonding clay commonly used is produced in deletion, make this product that chemical reaction just take place in the time of 1100 ℃～1300 ℃, than low 120～320 ℃ of traditional product, reduce energy consumption, and under nitrogen environment, generate high fine and close silicon nitride, thereby improve its physicochemical property; Simultaneously, because of removing bonding clay, siliceous mullite brick refractoriness under load of the present invention also is improved largely than former aluminum silicon carbide brick; In addition, technology of the present invention is simpler, is easy to realize, can reduce production costs greatly, helps large-scale promotion and uses.
Embodiment
Below in conjunction with embodiment the present invention is done further explanation.
Embodiment 1:
A kind of siliceous mullite brick comprises high grade bauxite, metallic silicon power and spent pulping liquor, and high grade bauxite is for aluminium content is 88%, volume density is 3.25g/cm
3Alumina; Metallic silicon power is 97% silica flour for Pure Silicon Metal content; The density of spent pulping liquor is 1.25g/cm
3The content of high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 75 parts, 18 parts, 2 parts.
The preparation method of siliceous mullite brick of the present invention may further comprise the steps: (1) takes by weighing according to the above-mentioned raw materials prescription and respectively organizes raw material: (2) are put into mixer respectively with each group raw material and are mixed lasting 20 minutes; (3) mixed raw material is put into the pressing machine die cavity and suppress, make work in-process, half-finished volume density is 2.7g/cm
3(4) work in-process that suppress being put into kiln fires, feed nitrogen, with insulation after per hour 5 ℃ heat-up rate rises to 1150 ℃ 3 hours, work in-process generation chemical reaction, and under nitrogen environment, generate high fine and close silicon nitride, thereby improve its physicochemical property; (5) take out siliceous mullite brick in the kiln, be cooled to room temperature after, promptly get siliceous mullite brick of the present invention; Then it is tested, and the packing warehouse-in.
Embodiment 2:
A kind of siliceous mullite brick comprises high grade bauxite, metallic silicon power and spent pulping liquor, and high grade bauxite is for aluminium content is 89%, volume density is 3.25g/cm
3Alumina; Metallic silicon power is 97% silica flour for Pure Silicon Metal content; The density of spent pulping liquor is 1.1g/cm
3The content of high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 80 parts, 10 parts, 4 parts.
The preparation method of siliceous mullite brick of the present invention may further comprise the steps: (1) takes by weighing according to the above-mentioned raw materials prescription and respectively organizes raw material: (2) are put into mixer respectively with each group raw material and are mixed lasting 10 minutes; (3) mixed raw material is put into the pressing machine die cavity and suppress, make work in-process, half-finished volume density is 2.7g/cm
3(4) work in-process that suppress are put into kiln and fire, with insulation after per hour 10 ℃ heat-up rate rises to 1200 ℃ 2.5 hours, work in-process generation chemical reaction, and under nitrogen environment, generate high fine and close silicon nitride, thus improve its physicochemical property; (5) take out siliceous mullite brick in the kiln, be cooled to room temperature after, promptly get siliceous mullite brick of the present invention; Then it is tested, and the packing warehouse-in.
Embodiment 3:
A kind of siliceous mullite brick comprises high grade bauxite, metallic silicon power and spent pulping liquor, and high grade bauxite is for aluminium content is 90%, volume density is 3.3g/cm
3Alumina; Metallic silicon power is 99% silica flour for Pure Silicon Metal content; The density of spent pulping liquor is 1.25g/cm
3The content of high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 85 parts, 14 parts, 5 parts.
The preparation method of siliceous mullite brick of the present invention may further comprise the steps: (1) takes by weighing according to the above-mentioned raw materials prescription and respectively organizes raw material: (2) are put into mixer respectively with each group raw material and are mixed lasting 30 minutes; (3) mixed raw material is put into the pressing machine die cavity and suppress, make work in-process, half-finished volume density is 2.75g/cm
3(4) work in-process that suppress being put into kiln fires, feed nitrogen, with insulation after per hour 12 ℃ heat-up rate rises to 1250 ℃ 3.5 hours, work in-process generation chemical reaction, and under nitrogen environment, generate high fine and close silicon nitride, thereby improve its physicochemical property; (5) take out siliceous mullite brick in the kiln, be cooled to room temperature after, promptly get siliceous mullite brick of the present invention; Then it is tested, and the packing warehouse-in.
Embodiment 4:
A kind of siliceous mullite brick comprises high grade bauxite, metallic silicon power and spent pulping liquor, and high grade bauxite is for aluminium content is 90%, volume density is 3.35g/cm
3Alumina; Metallic silicon power is 97% silica flour for Pure Silicon Metal content; The density of spent pulping liquor is 1.35g/cm
3The content of high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 90 parts, 16 parts, 6 parts.
The preparation method of siliceous mullite brick of the present invention may further comprise the steps: (1) takes by weighing according to the above-mentioned raw materials prescription and respectively organizes raw material: (2) are put into mixer respectively with each group raw material and are mixed lasting 20 minutes; (3) mixed raw material is put into the pressing machine die cavity and suppress, make work in-process, half-finished volume density is 2.8g/cm
3(4) work in-process that suppress being put into kiln fires, feed nitrogen, with insulation after per hour 15 ℃ heat-up rate rises to 1300 ℃ 3 hours, work in-process generation chemical reaction, and under nitrogen environment, generate high fine and close silicon nitride, thereby improve its physicochemical property; (5) take out siliceous mullite brick in the kiln, be cooled to room temperature after, promptly get siliceous mullite brick of the present invention; Then it is tested, and the packing warehouse-in.
Through check, the siliceous mullite brick in the various embodiments described above, its characteristic is as follows: Al
2O
3〉=65%; Normal temperature is withstand voltage 〉=and 108; Fe
2O
3≤ 0.8%; 0.2Mpa refractoriness under load 〉=1680 ℃; Refractoriness 〉=1790 ℃; Thermal shock resistance (1100 ℃ of water-cooleds) 13 times; Volume density 〉=2.7g/m
3
This shows, siliceous mullite brick of the present invention, by overcoming technology prejudice, make siliceous mullite brick raw material silicon carbide commonly used into Pure Silicon Metal, and deletion production refractory materials bonding clay commonly used, make this product that chemical reaction just take place in the time of 1100 ℃～1300 ℃, than low 120～320 ℃ of traditional product, reduce energy consumption, and under nitrogen environment, generate high fine and close silicon nitride, thereby improve its physicochemical property; Simultaneously, because of removing bonding clay, siliceous mullite brick refractoriness under load of the present invention also is improved largely than former aluminum silicon carbide brick; In addition, technology of the present invention is simpler, is easy to realize, can reduce production costs greatly, helps large-scale promotion and uses.
The above only is a preferred implementation of the present invention; be noted that for those skilled in the art; under the prerequisite that does not break away from the principle of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (5)
1. siliceous mullite brick is characterized in that: comprise high grade bauxite, metallic silicon power and spent pulping liquor, described high grade bauxite is for aluminium content is 88～90%, volume density is 3.25～3.35g/cm
3Alumina; Described metallic silicon power is 97～99% silica flour for Pure Silicon Metal content; The density of described spent pulping liquor is 11～1.35g/cm
3The content of described high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 75～90 parts, 10～18 parts, 2～6 parts.
2. siliceous mullite brick according to claim 1 is characterized in that: described high grade bauxite is for aluminium content is 88%, volume density is 3.25g/cm
3Alumina; Described metallic silicon power is 97% silica flour for Pure Silicon Metal content; The density of described spent pulping liquor is 1.25g/cm
3
3. siliceous mullite brick according to claim 1 and 2 is characterized in that: the content of described high grade bauxite, metallic silicon power and spent pulping liquor is respectively according to mass fraction: 80～90 parts, 10～15 parts, 4～6 parts.
4. the preparation method of the described siliceous mullite brick of claim 1 is characterized in that may further comprise the steps:
(1) take by weighing according to composition of raw materials and respectively organize raw material:
According to mass fraction, raw material comprises 75～90 parts of high grade bauxite, 10～18 parts of metallic silicon powers, 2～6 parts of spent pulping liquors, and described high grade bauxite is for aluminium content is 88～90%, volume density is 3.25～3.35g/cm
3Alumina; Described metallic silicon power is that Pure Silicon Metal is 97～99% silica flour; The density of described spent pulping liquor is 1.1～1.35g/cm
3
(2) each group raw material is put into mixer respectively and mix, continue 10～30 minutes;
(3) mixed raw material is put into the pressing machine die cavity and suppress, make work in-process;
(4) work in-process that suppress are put into kiln and fire, under nitrogen environment, be incubated 2.5～3.5 hours after rising to 1100 ℃～1300 ℃ with 3～15 ℃ heat-up rate per hour;
(5) take out siliceous mullite brick in the kiln, be cooled to room temperature after, promptly get described siliceous mullite brick.
5. the preparation method of siliceous mullite brick according to claim 4, it is characterized in that: described half-finished volume density is 2.7g/cm
3
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN 201110059774 CN102219530B (en) | 2011-03-14 | 2011-03-14 | Silicon mullite brick and preparation method thereof |
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| CN 201110059774 CN102219530B (en) | 2011-03-14 | 2011-03-14 | Silicon mullite brick and preparation method thereof |
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| CN102219530B CN102219530B (en) | 2013-08-14 |
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Cited By (7)
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| CN102701764A (en) * | 2012-06-08 | 2012-10-03 | 安徽瑞泰新材料科技有限公司 | Sintered alumina-silica refractory material and preparation method thereof |
| CN102701763A (en) * | 2012-06-08 | 2012-10-03 | 安徽瑞泰新材料科技有限公司 | Low-aluminum sintered alumina-silica refractory material and preparation method thereof |
| CN103626502A (en) * | 2013-06-03 | 2014-03-12 | 江苏江能新材料科技有限公司 | High-strength wear-resistant anti-corrosion brick and manufacturing method thereof |
| CN103864443A (en) * | 2014-02-26 | 2014-06-18 | 通达耐火技术股份有限公司 | Silicon mullite brick for cement kiln and preparation method thereof |
| CN104649690A (en) * | 2014-01-02 | 2015-05-27 | 岑溪市新建球陶瓷有限公司 | Preparation method of silicon and mullite brick |
| CN105222593A (en) * | 2015-10-10 | 2016-01-06 | 无锡兴达节能科技股份有限公司 | A kind of silicon nitride bonded silicon aluminum silicon carbide brick |
| CN107903031A (en) * | 2017-11-08 | 2018-04-13 | 常州万博金属构件厂 | A kind of high intensity Bone China biscuit |
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| CN1686922A (en) * | 2005-03-29 | 2005-10-26 | 郑州大学 | Method for preparing composite material combined with corundum based on bauxite beta-Sialon |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102701764A (en) * | 2012-06-08 | 2012-10-03 | 安徽瑞泰新材料科技有限公司 | Sintered alumina-silica refractory material and preparation method thereof |
| CN102701763A (en) * | 2012-06-08 | 2012-10-03 | 安徽瑞泰新材料科技有限公司 | Low-aluminum sintered alumina-silica refractory material and preparation method thereof |
| CN102701764B (en) * | 2012-06-08 | 2015-03-18 | 安徽瑞泰新材料科技有限公司 | Sintered alumina-silica refractory material and preparation method thereof |
| CN103626502A (en) * | 2013-06-03 | 2014-03-12 | 江苏江能新材料科技有限公司 | High-strength wear-resistant anti-corrosion brick and manufacturing method thereof |
| CN104649690A (en) * | 2014-01-02 | 2015-05-27 | 岑溪市新建球陶瓷有限公司 | Preparation method of silicon and mullite brick |
| CN103864443A (en) * | 2014-02-26 | 2014-06-18 | 通达耐火技术股份有限公司 | Silicon mullite brick for cement kiln and preparation method thereof |
| CN103864443B (en) * | 2014-02-26 | 2016-01-06 | 通达耐火技术股份有限公司 | Cement kiln siliceous mullite brick and preparation method thereof |
| CN105222593A (en) * | 2015-10-10 | 2016-01-06 | 无锡兴达节能科技股份有限公司 | A kind of silicon nitride bonded silicon aluminum silicon carbide brick |
| CN107903031A (en) * | 2017-11-08 | 2018-04-13 | 常州万博金属构件厂 | A kind of high intensity Bone China biscuit |
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| CN102219530B (en) | 2013-08-14 |
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