Sustainable Mining and Metallurgy

This paper introduced the crystallization of equipment and pipeline in the acid-making cleaning system of Yantai Guorun Copper Co., Ltd., analyzed the composition and causes of the crystallization one by one, and finally had the conclusion that the chlorine element in copper concentrete and coals enter the smelting flue gas, and then enter the waste acid in the purification process, and react with calcium hydroxide to form calcium chloride, which leading to the high content of calcium in the reclaimed water returned to the cleaning process, and the formation of calcium sulfate causes the crystallization of equipment and pipeline in the cleaning process. The bench-scale test of removing chloride ion by ultra-high lime aluminum method was carried out, and the results could not achieve the effect in theory. Finally, through the control of raw and auxiliary materials, the chlorine element brought into the cleaning process by off-gas and the content of chloride ion in waste acid and reclaimed water was decreased, which generated less calcium content in reclaimed water and reduced the crystallization of cleaning equipment and pipeline, thus the acid making system can be operated normally and stably.