Method for firing volume-density controlled chromium oxide product

A technology of bulk density and chromium oxide, which is applied in the field of controlling the bulk density of chromium oxide products after burning, can solve the problems of difficulty in producing large-scale products, high bulk density of chromium oxide products, and pollution of the environment, so that the process is easy to control. , easy to achieve, low environmental pollution effect

Inactive Publication Date: 2008-07-23
SINOSTEEL LUOYANG INST OF REFRACTORIES RES
View PDF0 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the adoption of H 2 O/H 2 、CO/CO 2 , N 2 /H 2 Mixed gas, it is difficult to control in actual industrial production, and the volume density of fired chromium oxide products is very high
The production of chromium oxide products by electromelting has the disadvantage

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

Example Embodiment

[0011] Example 1:

[0012] Chromium oxide products choose D 50 =1.8μm Cr 2 O 3 Micropowder with added TiO 2 Sintering aid; the weight percentage of its composition is: Cr 2 O 3 : 99%; TiO 2 :1%. After secondary molding, it is loaded into the nitriding kiln, and the N is controlled by a precision flow meter. 2 / O 2 Mixed gas flow so that the partial pressure of oxygen in the mixed gas is at 10 -6 atm, and at the same time ensure that the pressure in the nitriding kiln is between 10-50Pa, and it is fired at a temperature of 1500 ° C for 2 hours. The bulk density of the chromium oxide product obtained in this example is 4.25 g / cm 3 , the apparent porosity is 16.7%.

Example Embodiment

[0013] Example 2:

[0014] Chromium oxide products choose D 50 =1.8μm Cr 2 O 3 Micropowder with added TiO 2 Sintering aid; the weight percentage of its composition is: Cr 2 O 3 : 97%; TiO 2 : 3%. After secondary molding, it is loaded into the nitriding kiln, and the N is controlled by a precision flow meter. 2 / O 2 Mixed gas flow so that the partial pressure of oxygen in the mixed gas is at 10 -4 atm, and at the same time ensure that the pressure in the nitriding kiln is between 10-50Pa, and it is fired at a temperature of 1450 ° C for 3 hours. The bulk density of the chromium oxide product obtained in this example is 4.41 g / cm 3 , the apparent porosity is 13.2%.

Example Embodiment

[0015] Example 3:

[0016] Chromium oxide products choose D 50 =1.8μm Cr 2 O 3 Micropowder with added TiO 2 Sintering aid; the weight percentage of its composition is: Cr 2 O 3 : 94%; TiO 2 : 6%. After secondary molding, it is loaded into the nitriding kiln, and the N is controlled by a precision flow meter. 2 / O 2 Mixed gas flow so that the partial pressure of oxygen in the mixed gas is at 10 -2 atm, and at the same time ensure that the pressure in the nitriding kiln is between 10-50Pa, and it is fired at a temperature of 1400 ° C for 8 hours. The bulk density of the chromium oxide product obtained in this example is 3.91 g / cm 3 , the apparent porosity is 26.7%.

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
Bulk densityaaaaaaaaaa
Bulk densityaaaaaaaaaa
Bulk densityaaaaaaaaaa
Login to view more

Abstract

The invention relates to a sintering method of chromium oxide product, of which the volume and density are controllable. Firstly, a mixed gas of N2O2 is filled into the nitriding kiln in which the chromium oxide products are prepared to be fired, meanwhile the flow of N2 and O2 is controlled to keep the oxygen partial pressure of the mixed gas between 10<-2>-10<-6>atm and ensure that the internal pressure is between 10pa to 50pa. Secondly, under the temperature between 1400 to 1500 degrees Centigrade, the chromium oxide product is treated with heat insulation for two to eight hours. The volume and density of chromium oxide product are between 3.8 to 4.8g/m<3>. The sintering method for chromium oxide product is characterized best in that the volume and density of the chromium oxide product can be controlled after sintering, and the production process is easy to control; the sintering temperature is fairly low with no pollution to chromium oxide products; in addition, the adoption of nitriding kiln contained with N2 in sintering technique is already mature at home, thus ensuring that the sintering method of chromium oxide product with controllable volume and density can be easily carried out in the industrial production.

Description

technical field [0001] The invention relates to a firing method of chromium oxide products, and mainly relates to a method for controlling the bulk density of fired chromium oxide products by controlling the oxygen partial pressure of mixed gas. Background technique [0002] Due to its excellent anti-corrosion performance, less pollution to molten glass and long service life, chromium oxide material is widely used as the hot surface lining material of alkali-free glass fiber tank kiln. As the key material of the inner lining of the hot surface of the tank kiln, there is no material that can replace it. However, with the accumulation of experience, it is found that the bulk density of chromium oxide products is too high, and its thermal shock resistance is very poor, and cracks are easy to occur during the heating process, resulting in a significant decrease in the corrosion resistance of the cracked area; at the same time, the bulk density is too high. Its apparent porosity...

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
IPC IPC(8): C04B35/64C04B35/66C04B35/12
Inventor 尹洪基耿可明徐延庆王金相范志辉石鹏坤胡飘孙红刚
Owner SINOSTEEL LUOYANG INST OF REFRACTORIES RES
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap