Sintered porous balls from rice husk for thermal insulation in iron and steel industries

Sintered porous balls were prepared from waste rice husk (RH) for thermal insulation purposes on the top of the ladles and tundishes in iron and steel industries. As the permanent insulating structure is not possible, temporary insulation is done by using agricultural wastes for economy that burn out and produce porous ash-based insulating layer. But the layer formed is non-uniform in thickness, causing non-uniform cooling pattern of the stored steel and variation in properties. Also burning of the wastes causes various occupational health hazards. Reduction in health risk with uniform insulating layer thickness could be achieved by using the temporary insulation as a sintered porous ball. Such a developmental work is described here using RH as the starting material. Ash generated is mesoporous in characteristic giving insulating properties; sintered form does not allow any fly off thus controls pollution and health hazards; and the ball shapes will result in uniform spreading with a uniform thickness of insulation.