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CN-121990823-A - High-temperature corrosion-resistant fused casting high-zirconium brick and application thereof

CN121990823ACN 121990823 ACN121990823 ACN 121990823ACN-121990823-A

Abstract

The invention relates to a high-temperature corrosion-resistant fused casting high-zirconium brick and application thereof, and belongs to the technical field of refractory materials. The high-zirconium brick comprises ：ZrO 2 ：96.4-97.6%,SiO 2 ：1.18-1.70%,Al 2 O 3 ：0.15-0.80%,Na 2 O：0.04-0.08%,K 2 O：0.02-0.06%,La 2 O 3 ：0.20-0.30%,SnO 2 ：0.20-0.30%, of other impurities with the content of less than 0.10 percent in mass fraction. The method is characterized in that La 2 Sn 2 O 7 is used as a raw material, la 2 O 2 generated by decomposition is used as a heterogeneous nucleation core to refine a grain structure in a high-temperature casting process, so that high-temperature strength and toughness are improved, and SnO 2 is decomposed in a reducing atmosphere to release oxygen, so that bubbles are promoted to be combined and escape, the porosity is obviously reduced, and the compactness is improved. The data of the embodiment show that the volume density of the brick body reaches 5.59-5.68 g/cm < 3 >, the porosity is lower than 0.61%, the erosion resistance rate in the glass liquid at 1500 ℃ is as low as 0.28-0.34 mm/24h, the brick body shows excellent erosion resistance and high-temperature stability, and the brick body is suitable for harsh industrial environments such as glass kilns and the like.

Inventors

  • ZHANG HONGZHE
  • LI LONGGANG
  • WEI JIE
  • HAN GUANGJUN
  • ZHANG MU

Assignees

  • 河南省瑞泰科实业集团有限公司

Dates

Publication Date
20260508
Application Date
20251223

Claims (10)

  1. 1. The high-temperature corrosion-resistant fused cast high-zirconium brick is characterized by comprising the following components ：ZrO 2 ：96.4-97.6%,SiO 2 ：1.18-1.70%,Al 2 O 3 ：0.15-0.80%,Na 2 O：0.04-0.08%,K 2 O：0.02-0.06%,La 2 O 3 ：0.20-0.30%,SnO 2 ：0.20-0.30%, in percentage by mass, wherein the content of other impurities is less than 0.10%.
  2. 2. The high-temperature corrosion-resistant fused cast high-zirconium brick according to claim 1, wherein the high-temperature corrosion-resistant fused cast high-zirconium brick comprises the following components in percentage by weight, 97.13% of ZrO 2 , 1.60% of SiO 2 , 0.60% of Al 2 O 3 , 0.06% of Na 2 O, 0.04% of K 2 O, 0.25% of La 2 O 3 , 0.25% of SnO 2 and the content of other components is less than 0.10%.
  3. 3. The high temperature erosion resistant cast high zirconium brick according to claim 1, wherein the mass ratio of tin oxide to lanthanum oxide in the high temperature erosion resistant cast high zirconium brick is 1-1.1:1.
  4. 4. A method of making the high temperature erosion resistant fused cast high zirconium brick of any one of claims 1-3, comprising the steps of: s1, taking corresponding raw materials according to the Gao Gaozhuan proportion, wherein the raw materials comprise desilication zircon, a silicon dioxide source and La 2 Sn 2 O 7 ; s2, melting the uniformly mixed raw materials in an electric arc furnace to form a melt; and S3, casting the molten liquid into a casting mold to be solidified, carrying out heat preservation and annealing, and processing to obtain the high-zirconium brick.
  5. 5. The method according to claim 4, wherein the casting temperature in the step S3 is more than or equal to 1950 ℃ and the casting rate is 10-50kg/S.
  6. 6. The method according to claim 4, wherein the La 2 Sn 2 O 7 is prepared in the following manner in the step S1: a. Dissolving lanthanum and tin precursors in deionized water according to a stoichiometric ratio; b. Adding complexing agent, heating and stirring to form uniform sol, and heating to 300 ℃ to obtain precursor powder; c. Calcining the precursor powder to obtain La 2 Sn 2 O 7 .
  7. 7. The method of claim 6, wherein the precursor of lanthanum in the step a is any one of lanthanum nitrate or lanthanum citrate, the precursor of tin is stannic chloride, and the molar ratio of lanthanum to tin is 1:1.
  8. 8. The method of claim 6, wherein the complexing agent in step b is citric acid and the molar ratio of citric acid to metal ions is 1-2:1.
  9. 9. The method of claim 6, wherein the calcination in step c is performed at 600-800℃for 2-4 hours.
  10. 10. Use of a high temperature erosion resistant fused cast high zirconium brick according to any one of claims 1-3 in the field of glass furnaces.

Description

High-temperature corrosion-resistant fused casting high-zirconium brick and application thereof Technical Field The invention belongs to the technical field of refractory materials, and particularly relates to a high-temperature corrosion-resistant fused casting high-zirconium brick and application thereof. Background The fused cast refractory material, especially the fused cast high-zirconium brick, is widely applied to key parts of high-temperature industrial kilns such as glass melting furnaces, metallurgical furnaces and the like, such as tank walls, feed inlets, liquid flow holes and the like of the glass melting furnaces, and the service life and production efficiency of the kiln are directly determined by the properties of the fused cast refractory material, especially the fused cast high-zirconium brick, because the fused cast refractory material has the characteristics of compact crystal structure, high mechanical strength, excellent erosion resistance and the like. The main component of the fused cast high-zirconium brick is zirconia (ZrO 2), and the content is usually more than 90%. However, pure zirconia undergoes a crystal form transformation between monoclinic phase (m), tetragonal phase (t) and cubic phase (C) during cooling, wherein the tetragonal phase-monoclinic phase (t→m) transformation occurring around 1000 ℃ is accompanied by a volume expansion of about 3-5%, which can lead to a huge stress inside the brick body to crack. To solve this problem, the prior art generally adds an appropriate amount of a stabilizer such as calcium oxide (CaO), yttrium oxide (Y 2O3) or magnesium oxide (MgO) to ZrO 2, and can form a stable cubic phase or metastable tetragonal phase at room temperature, thereby avoiding the occurrence of destructive phase transition. Although the application of the stabilizer solves the phase change cracking problem of zirconia to a certain extent, the conventional fused cast high-zirconium brick still has insufficient phase stability at high temperature for a long period and corrosion resistance bottleneck caused by a grain boundary glass phase in the face of more and more severe high-temperature working conditions, and in addition, in order to pursue high corrosion resistance, it is generally desirable that the brick body has the highest possible density and zirconia content, but this tends to lead to reduced toughness of the material and poor thermal shock resistance. It is a challenge in the prior art how to maintain extremely high erosion resistance while achieving good thermal shock resistance. Therefore, there is an urgent need in the art to develop a novel fused cast high zirconium brick which not only needs to have high room temperature and high temperature strength, but also needs to have excellent long-term phase stability and super corrosion resistance against severe chemical environments, thereby remarkably prolonging the service life in high temperature industrial kilns. Disclosure of Invention In order to solve the technical problems in the background technology, the La 2Sn2O7 is adopted to stabilize the fused cast high-zirconium brick, so that the corrosion resistance of the fused cast high-zirconium brick can be obviously improved, and certain heat stability is considered. The invention aims to provide a high-temperature corrosion-resistant fused cast high-zirconium brick which is characterized by comprising the following components ：ZrO2：96.4-97.6%,SiO2：1.18-1.70%,Al2O3：0.15-0.80%,Na2O：0.04-0.08%,K2O：0.02-0.06%,La2O3：0.20-0.30%,SnO2：0.20-0.30%, in percentage by mass, wherein the content of other impurities is less than 0.10%. Further, the high-temperature corrosion-resistant cast high-zirconium brick comprises 97.13% of ZrO 2, 1.60% of SiO 2, 0.60% of Al 2O3, 0.06% of Na 2 O, 0.04% of K 2 O, 0.25% of La 2O3, 0.25% of SnO 2 and less than 0.10% of other components. Further, the mass ratio of the tin oxide to the lanthanum oxide in the high-temperature corrosion-resistant cast high-zirconium brick is 1-1.1:1. The invention also aims to provide a preparation method of the high-temperature corrosion-resistant fused cast high-zirconium brick, which is characterized by comprising the following steps of: S1, taking corresponding raw materials according to the Gao Gaozhuan proportion, wherein the raw materials comprise desilication zircon, a silicon dioxide source, a sodium oxide source and La 2Sn2O7; s2, melting the uniformly mixed raw materials in an electric arc furnace to form a melt; and S3, casting the molten liquid into a casting mold to be solidified, carrying out heat preservation and annealing, and processing to obtain the high-zirconium brick. Furthermore, in the step S3, the casting temperature is more than or equal to 1950 ℃, and the casting rate is 10-50kg/S. Further, the preparation method of La 2Sn2O7 in S1 is as follows: a. Dissolving lanthanum and tin precursors in deionized water according to a stoichiometric ratio; b. Adding complexing agent, heati