The idea of a circular economy, incorporating industrial waste, is now being extended to refractories as well but enough importance was not given in recent past how to recycle spent refractories. As a result, a significant portion of spent refractories were used for landfilling or repurposed for road maintenance. However, recent initiatives aim to start using different spent refractories through proper processing techniques and to maximize the utilization to achieve several advantages. Recycling of spent refractories not only reduces the consumption of prime raw materials but also controls the carbon emissions associated with their high-temperature processing. Since substantial portion of refractories are utilized in high-temperature applications and many a times come in direct contact with molten metals or steel and therefore the quality of spent refractories is very crucial to prevent operational failures. Challenges in recycling include the lack of established technologies for sorting spent refractories based on their characteristics after collecting from muck or debris. In most of the times manual sorting has been employed in numerous instances. In that case, effective methodologies and highly skilled labor are essential for transforming spent refractories into an acceptable and consistent manner. Common recycling processes are cleaning, crushing, grinding, sorting, segregation, calcination etc. but chemical treatment is also another process to remove slags or other impurities in specific cases.

This study discusses a systematic industrial approach to obtain different grades of refractory raw materials from spent refractories and incorporating them into various formulations, followed by performance monitoring.