Development and application of dense fused corundum bricks

Development and application of dense fused corundum bricks

With the rapid development of modern industry, the requirements for refractory materials in petrochemical, metallurgical and other industries are constantly increasing. They must not only have high high-temperature strength, but also have good thermal shock stability and corrosion resistance. To this end, we have developed dense 99% fused corundum bricks, which have been used on heaters and achieved good results. The bricks not only have a breakthrough in strength, but also have significant improvements in thermal shock resistance.

1. Development of dense 99 fused corundum bricks

Australian fused corundum sand is selected (A1203>99.3%, Si02<0.2%, Na20+K20<0.2%, porosity <6%, particle size 0.088~5mm, processed through strict iron removal process), prepared according to grade 6 particle size , mix in stages in a forced mixer, each mixing time is 2 to 3 minutes. After complete mixing, add an appropriate amount of inorganic and organic binders and mix for 3 minutes, then add AI203 micro powder (10% to 20%) and mix for 3 minutes. ~5 minutes, and then place in a clean container to mix for 24~48 hours. It is machine-pressed and formed in a metal cavity film. After the green body is taken out and dried, the strength can reach 5MPa. The green body is put into a fuel-saving high-temperature inverted flame kiln. The heating rate is room temperature ~ 700°C for 30 hours, and 700 ~ 1100°C for 14 hours. , 1100~1800℃ for 5~7h, keep warm for 6~8h, stop the kiln and cool down to 900℃ for forced cooling.

After testing, the performance indicators of the 99% fused corundum brick made by the above process fully meet the technical requirements.

2. Application

The developed DGZ-99 fused corundum brick is an ideal lining material for high-temperature and high-pressure gasifiers in the petrochemical industry. It also fully meets the technical requirements of various domestic pressurized synthetic ammonium gasifiers. It is expected to replace imported 99 corundum bricks in the domestic 300,000 tons synthetic ammonium heavy oil pressurized gasifier, and has good application prospects.