As we know that sulfide bed boiler, it has coal burning and high vulcanization speed of up to 5m / s and some parts localized up to 35m / s.Under the high temperature has a strong scouring effect on the lining refractory,combing with chemical reaction of impurities and frequency   heat exchange, which is resulting in the original use of refractory lining erosion, wear, peeling and collapse. So the furnace has to be stopped regularly and repaired accordingly.