RSW glass melting in indigenously developed 10L coarse body refractory crucible with fine body layer by tilt casting method using 10L scale Raising Hearth furnace, has been successful. This is currently being scaled up to a 60L scale using in-house fabricated 60L Crucible in the existing pre-melting furnace.
For complete densification and desired phase formation, these crucibles were required to be fired at higher temperature, i.e., more than 1500oC. The exercise was undertaken with participation of industry wherein the green coated crucibles were biscuit fired at 900oC followed by 1400oC and finally sintered at 1520oC. Two such crucibles have been fired and more than 72% mullite was formed at this temperature with significantly lower cristobalite and corundum phases. Two numbers of in-house fabricated 60L scale stirrer biscuit fired at 960oC was also successfully carried out.