The present application provides an ice blast cleaning method for a layer of slag on a surface. The ice blast cleaning method may include the steps of maintaining the surface with the layer of slag thereon at an elevated temperature, shooting a number of ice pellets at the layer of slag on the surface, and loosening the layer of slag on the surface via a mechanical impact of the ice pellets on the layer of slag and a thermal shock caused by a temperature differential between the ice pellets and the layer of slag.