Seale formation is a problem which frequently occures in the wet ash handling system in call fired power plants. Introduced in this peper is a new method of scale prevention by using active and inert crystals

which are suitable to the recycled ash sluicing system

especially to the dense ash handling system. The research and testing results show that this method is able to solve all-process scaling problem without adding any chemicals. It is easy for operation and has a wide application. No matter how high the scale tendency of ash slurry

the speed of scale formation can be reduced by at least 10 times.