Lime Refractory

The hydration-resistant lime (CaO) refractory technology developed and patented by CSIR-Central Glass & Ceramic Research Institute (Indian Patent No. IN269921) utilizes the thermodynamic stability of CaO for demanding metallurgical applications. Despite its inherent advantages, CaO has traditionally remained underutilized due to its high susceptibility to atmospheric hydration. The present technology overcomes this limitation through a rapid plasma-assisted densification route, producing low-porosity, hydration-resistant CaO within minutes, making it industrially viable. This enables the deployment of lime-based refractories offering exceptional chemical compatibility with high-basicity slags, reduced contamination, and improved refining efficiency—particularly in advanced steelmaking processes such as vacuum metallurgy, where refractory–slag interactions critically influence steel cleanliness.

The developed hydration-resistant lime refractory is particularly suited for high-basicity, low-contamination, and refining-intensive environments, including:

1. Vacuum metallurgy units (VD, VOD, RH degasser)
2. Secondary steelmaking (ladle furnace operations)
3. Basic Oxygen Furnace (BOF) and Electric Arc Furnace (EAF)
4. High-purity steel and special alloy production

1. Highly resistant to basic and siliceous metallurgical slags
2. Maintains integrity till fusion points near 2600^oC
3. Sintered, hydration-resistant versions allow for safer storage and longer service life compared to untreated lime, which readily reacts with atmospheric moisture
4. Rapid and techno-economically viable processing via plasma-assisted densification (1–3 minutes)
5. Utilization of abundant natural resources, supporting cost and supply chain advantages