风化壳淋积型稀土矿一维柱浸过程的模拟（英文）

Simulation of one-dimensional column leaching of weathered crust elution-deposited rare earth ore

通过杯浸试验确定浸矿的离子交换模型为Kerr模型,得到Kerr模型的选择系数为12.59×10^(-10)L^2/g^2;采用对流-弥散方程描述柱浸过程铵根离子和稀土离子的运移规律,通过Kerr模型确定对流-弥散方程中的源汇项,运用顺序非迭代法解具有强非线性的对流-弥散方程,模拟稀土离子在土柱中的运移过程。与室内一维柱浸试验稀土离子的穿透曲线进行比较,两者的相关系数达到0.8724,说明本方法可以较为准确地模拟风化壳淋积型稀土矿一维柱浸过程。分析硫酸铵溶液浓度对稀土浸取率的影响,结果发现,最优硫酸铵溶液浓度(C_(op)^(NS))与稀土品位(η)满足线性关系。

The ion exchange model of the leaching process was determined via batch leaching experiments using the Kerr model, with the selectivity coefficient experimentally determined to be 12.59×10^-10 L^2/g^2. Solute transport laws of ammonium ions (NH4 +) and rare earth ions (RE^3+) in column leaching were described by the convection-dispersion equation (CDE). The source and sink in the CDE were determined by the Kerr model. The CDE with strong nonlinearity was solved using the sequential non-iterative method. Compared with the breakthrough curve of RE^3+, the correlation coefficient between the simulated and experimental curves reached 0.8724. Therefore, this method can simulate the one-dimensional column leaching of weathered crust elution-deposited rare earth ore. Moreover, the effects of different concentrations of ammonium sulfate ((NH4)2SO4) solution on the leaching rate of rare earth were analyzed. The optimal concentration of the (NH4)2SO4 solution had a linear relationship with the rare earth grade.