Low Thermal Conductivity Mullite Composite Brick
Category:
Description:
Main Types of Low Thermal Conductivity Mullite Composite Refractory Bricks
Low thermal conductivity mullite composite refractory bricks are classified into three types according to their structure:
- Homogeneous low‑thermal‑conductivity brick : With The material is primarily a 60/70-grade mullite homogenate, with fine redscheelite (Al₂SiO₅) powder added to optimize thermal shock resistance. The Al₂O₃ content ranges from 55% to 75%, and the bulk density is 2.0–2.2 g/cm³.
- Multi-layer composite brick : Work layer ( M70 mullite + 12% silicon carbide), insulation layer (M60 mullite), and thermal barrier layer (zirconia fiberboard), with a thermal conductivity of only 1.2 W/(m·K) at 1000℃.
- Zirconia-mullite brick : Introducing zircon sand ( ZrSiO₄) undergoes phase transformation toughening, with a bulk porosity of 18%–22% and a spalling resistance of up to 20 cycles (water cooling at 1100°C).
Production Process
Core process focuses on reducing thermal conductivity:
- Raw Material Processing : Select low‑impurity aggregates such as tabular corundum and electrofused mullite, and control… Fe₂O₃ ≤ 0.6%.
- Structural composite : Multi-layer bricks use a graded mix (working layer Al₂O₃ ≥ 70%, insulation layer ≤ 65%), sintered at 1700°C after isostatic pressing.
- Micropore Technology : Add pore-forming agents (such as polystyrene spheres) to create closed pores, increasing the porosity to… 25%–30%.
- Zirconia-mullite synthesis : Bauxite and zircon in A ZrO₂–mullite interwoven structure is formed through a 1600℃ reaction.
Application Scenarios
- Cement Kiln Transition Zone : Replace silicon carbide bricks to reduce kiln shell temperature. At 50–80°C, coal consumption per ton of clinker is reduced by 0.3 kg.
- Glass melting furnace : Heat‑storage chamber grid, resistant to alkali vapor erosion ( Na₂O penetration depth < 1 mm).
- Petroleum Cracking Furnace Radiation section lining, resistant to… 1100℃ sulfur‑containing flue gas.
- Ceramic Roller Kiln : Directly exposed to the flame zone ( 1400℃), and its thermal shock resistance is superior to that of traditional high-alumina bricks.
Performance Advantages
- Ultra-low thermal conductivity ： At 1000℃, the thermal conductivity is 1.2 W/(m·K), which is 60% of that of silicomosite bricks.
- High-temperature stability : The softening temperature of the alloy is ≥1650℃, and the creep rate at 1600℃ is <0.5%.
- Significant energy savings Annual Emission Reduction from Cement Kiln Applications Approximately 2,700 tons of CO₂ per line.
- Longevity Design : Remaining It can still be used safely at a thickness of 120mm (traditional bricks require the kiln to be shut down for replacement).
Physicochemical Indicators
Indicator
|
Homogeneous brick
|
Multi-layer composite brick
|
Test standards
|
Al₂O₃ content
|
65%–75%
|
55%–70%
|
GB/T 6900
|
Bulk density (g/cm³)
|
2.0–2.2
|
1.8–2.0
|
GB/T 2998
|
Compressive Strength (MPa)
|
≥50
|
≥35
|
GB/T 5072
|
Thermal Conductivity (1000℃)
|
≤1.5 W/(m·K)
|
≤1.2 W/(m·K)
|
YB/T 4130
|
Thermal Shock Stability (cycles)
|
≥15
|
≥25
|
GB/T 30873
|
Note: Composite bricks offer the best overall performance, but they are costly. 20%–30%; zirconia-mullite bricks are more suitable for applications with fluctuating operating temperatures.
Keywords:
Low Thermal Conductivity Mullite Composite Brick
Previous page:
Online Message
Related products
Do you want to get a complete solution as soon as possible?
Click the button to submit your request information, and we’ll contact you promptly once we receive it.
Contact Us
whatsapp:+8615936268068
Phone:+86-15936268068
Email:zzjsrefractory@gmail.com
Address: Chengguan Industrial Zone, Xinmi City, Henan Province
Tiktok
Copyright © Zhengzhou Jinshan Refractories Material Co., Ltd.
Powered by www.300.cn Supports IPV6 Privacy Agreement