Silicon saturation coefficient changes in hydrogarnets during the Bayer process with lime addition  

作　　者：Guozhi Lü Ting’an Zhang Xiaofeng Zhu Chaozhen Zheng Yanxiu Wang Weiguang Zhang Zimu Zhang 

机构地区：[1]Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education, School of Metallurgy, Northeastern University

出　　处：《Chinese Journal of Chemical Engineering》2019年第8期1965-1972,共8页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(51874078,U1710257,U1202274);Fundamental Research Funds for the Central Universities of China(N140203005,N140204015);the Science and Technology Research Projects of Liaoning Education Department(L2014096);the State Key Laboratory of Pressure Hydrometallurgical Technology of Associated Nonferrous Metal Resources(YY2016006)

摘　　要：The relationship between the silicon saturation coefficient of hydrogarnets and Bayer reaction parameters was studied. The peak position, crystal plane spacing, and cell edge length of typical hydrogarnet patterns were calculated to find the key factors influencing the relationship. The results showed that the crystal face(420) is the optimal garnet growth direction during hydration and crystal growth along the faces(521) and(611) were not affected significantly by the varying experimental conditions. The reaction temperature significantly influenced the silicon saturation coefficient of hydrogarnets. The silicon saturation coefficient of hydrogarnets increased from 0.2 to about 1.0 in the temperature range of 30–270 °C and a rapid expansion process was observed in the temperature range of 120–150 °C. Moreover, the reaction time, alumina concentration, and C/S were shown to be less important factors. Averaging the results obtained by the 3 methods was shown suitable for calculating the SiO2 saturation coefficient of hydrogarnets. The calculated results of the Al2O3 and SiO2 contents matched the actual ones. However, the actual SiO2 content was about10 % less than the calculated one for SiO2 saturation coefficients higher than 1.The relationship between the silicon saturation coefficient of hydrogarnets and Bayer reaction parameters was studied. The peak position, crystal plane spacing, and cell edge length of typical hydrogarnet patterns were calculated to find the key factors influencing the relationship. The results showed that the crystal face（420） is the optimal garnet growth direction during hydration and crystal growth along the faces（521） and（611） were not affected significantly by the varying experimental conditions. The reaction temperature significantly influenced the silicon saturation coefficient of hydrogarnets. The silicon saturation coefficient of hydrogarnets increased from 0.2 to about 1.0 in the temperature range of 30–270 °C and a rapid expansion process was observed in the temperature range of 120–150 °C. Moreover, the reaction time, alumina concentration, and C/S were shown to be less important factors. Averaging the results obtained by the 3 methods was shown suitable for calculating the SiO2 saturation coefficient of hydrogarnets. The calculated results of the Al2O3 and SiO2 contents matched the actual ones. However, the actual SiO2 content was about10 % less than the calculated one for SiO2 saturation coefficients higher than 1.

关 键 词：HYDROGARNET SATURATION COEFFICIENT PEAK position Crystal plane SPACING Cell edge length 

分 类 号：TG1[金属学及工艺—金属学]