What is a limitation of refractory material?

The limitation of refractory material is that it does not prevent sludge and scale from forming. Refractory materials are designed to withstand high temperatures and provide insulation in high-heat environments, such as furnaces and kilns. However, they do not inherently possess any special properties to inhibit the accumulation of sludge or scale, which can build up due to chemical reactions and impurities present in the materials being processed. This build-up can decrease the efficiency of thermal systems and may lead to more frequent maintenance and cleaning requirements.

In contrast, options such as enhancing thermal efficiency, preventing dust from escaping, and reducing heat loss highlight beneficial aspects of refractory materials. These materials indeed play a vital role in improving thermal efficiency by limiting heat loss and helping to maintain the desired temperatures within thermal systems. However, these benefits do not address the issue of sludge and scale formation, which remains a significant limitation in the practical application of refractory materials.