Abstract: It has put forward a new technology of wastewater cascade cycle utilization and zero discharge，from the PCC process water to cooked slurry filtrate，to the kiln gas purification water，and then to wastewater treatment，and finally to the calcium hydroxide process water，water quality changed step by step from the point of view，these had constituted a step recycling process from high to low.In addition to losing a small amount of waste water on evaporation，drying，gas washing links，the waste water cascade cycle using the new process the industrial wastewater all realized clean and recycling targets. At the same time，the process had also achieved the goal of low cost and low carbon purification treatment lime kiln gas on the large-scale calcium carbonate enterprises.The new technology of wastewater cascade cycle utilization and zero discharge that will provide reference for the large-scale calcium carbonate enterprises to achieve resource utilization，recycling economy， and low-carbon economy.

Key words: calcium carbonate, calcium chemical products, wastewater cascade cycle utilization and zero discharge