Estimation of the Gibbs Free Energy for Calcium Aluminate Sulphate Hydrates Using Iterative Least Squares Regression Method

4th Annual International Workshop on Materials Science and Engineering

Wu, Xianxi^1 ; Lan, Jun^1 ; Jiang, Hongshi^1

College of Chemical Engineering, Guizhou University, Guiyang

550025, China^1

关键词: Alumina production;    Calcium aluminate;    Iterative least squares;    Optimal selection;    Recursive least square methods;    Regression equation;    Regression method;    Tree diagram;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/381/1/012099/pdf
DOI  :  10.1088/1757-899X/381/1/012099

来源: IOP

【 摘 要 】

The iterative least squares method was used for the estimation of the Gibbs free energy G of calcium aluminate sulphate hydrates the lime desulfurization product in alumina production. By means of the tree diagram theory, the optimal selection of exponential power Xi in the regression equation is realized. The recursive least square method was used to solve the regression equation, and a regression method for estimating the Gibbs free energy of calcium aluminate sulphate hydrates was obtained. The Gibbs free energies of two kinds of calcium aluminate sulphate hydrates at 343K were estimated by this method. The experimental results were consistent with the estimated Gibbs free energies. It shows that the estimated method is correct and the result is reliable. The Gibbs free energy of calcium aluminate sulphate hydrates at any temperature can be estimated by this means. The study will provide theoretical and experimental basis for the lime desulfurization and synthesis of calcium aluminate sulphate hydrates by process of alumina production.