Formation mechanism of scale in iron ore slurry filtration backwater pipe
FAN Jian-jun,ZHENG Fu-qiang,GUO Yu-feng,ZANG Long,WANG Lei,YAO Hong-guo
1.Technology Center, Taiyuan Iron and Steel (Group)Co., Ltd., Taiyuan 030003, Shanxi, China;2.School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, Hunan, China; 3.Lanxian Mine Corporation, Taiyuan Iron and Steel(Group)Co., Ltd., Lüliang 035504, Shanxi, China
Abstract:Abstract: The scale was accumulated in the backwater pipe of iron ore slurry filtration, when the sulfuric acid was replaced by R31 filter aid for filtrating iron ore slurry in a domestic beneficiation plant.In order to reveal the chemical reaction mechanism of scale formation, the mineral phase of scale was confirmed to be calcium carbonate by Xray diffraction analysis. The fluorescence analysis method was used to quantitatively analyze the elemental composition of different filtrates. The simulation experiment of calcium carbonate formation was investigated. The results show that the CO2-3 reacted with Ca2+ to generate the CaCO3 precipitate after mixing the R31 filtrate with sulfuric acid filtrate. The CO2-3 was produced by the dissolution of CO2 in water, and the CO2 was formed from decarboxylation of carboxyl (-COOH) in the filter of R31 filter aid in alkaline solution. The Ca2+ ions were formed by the reaction of sulfuric acid and calciumbearing mineral in iron concentrate during filtration process. Finally, the chemical reaction mechanism of the scale formation in backwater pipe of iron ore slurry filtration was revealed.
范建军1,郑富强2,郭宇峰2,臧龙3,王磊3,姚洪国2. 铁矿浆过滤回水管道结垢物形成机制[J]. 钢铁研究学报, 2020, 32(6): 476-482.
FAN Jian-jun1,ZHENG Fu-qiang2,GUO Yu-feng2,ZANG Long3,WANG Lei3,YAO Hong-guo2. Formation mechanism of scale in iron ore slurry filtration backwater pipe. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(6): 476-482.