Preheater Process In Cement Industry. Rotary kiln is used widely in cement plant and we design and produce newstyle rotary kiln with vertical preheater which takes use of the heat of the flue gas coming out from the kiln end to preheat the dolomite to 800℃ in the preheater During this process the dolomite is push out by hydraulic pushrod and get into the Rotary Kiln through transfer slide ...