... . Raw material:limestone,clay, gypsum, iron ore, sand 3. Product type: 32.5R or 42.5N Portland cement in accordance with ... economy benefits can be acquired.2) The high-efficiency low-resistance five-stage cyclone pre-heater and cdc furnace system with ... , high classification efficiency, high heat exchanging efficiency and low system resistance will be adopted at the kiln inlet, so as to ...