基于二元平衡解吸模型的离子型稀土浸矿剂用量计算方法

Calculation method of leaching agent dosage in ion-adsorption type rare earth using DED model

以硫酸铵作为浸矿剂浸取稀土时,其在矿土表面赋存形式分为可逆和不可逆两部分;根据铵在浸矿中的作用,铵消耗分为三个部分:离子交换消耗、专性吸附消耗和维持浸矿剂浓度的消耗。本文结合铵的赋存形式和浸矿作用,采用二元平衡解吸模型(DED模型)刻画浸矿,通过数值拟合确定相应参数,提出一种针对离子型稀土的浸矿剂用量计算方法。结果表明:以福建屏南和江西信丰某离子型稀土矿为研究对象,设定稀土目标浸取率85.00%、90.00%和95.00%时,计算出相应浸矿剂用量;通过柱浸试验评价方法可行性,发现两种矿样实际浸取率分别达到85.93%、89.05%、94.22%和85.97%、90.55%、95.14%,与目标浸取率误差在1.5%以内。本方法在实验室具有良好效果,可以用于指导实际生产中的浸矿剂用量确定。

When ammonium sulfate is used as ore leaching to agent leach rare earth,the surface occurrence forms of ammonium in soil can be divided into reversible and irreversible parts,according to ammonium in the role of leaching ore,ammonium cost can be divided into three parts:ion exchange adsorption cost,obligate adsorption cost and the cost of maintain ore leaching concentration.In this paper,according to ammonium’s occurrence and role of leaching ore,a Dual-Equilibrium Desorption(DED)model was used to describe the leaching process.After the corresponding parameters were determined by numerical fitting,a calculating method of leaching agent dosage for ion-adsorption type rare earth was proposed.Taking the ion-adsorption type rare earth mines in Pingnan and Xinfeng of Fujian and Jiangxi province as research objects,the corresponding leaching agent dosage was calculated when the target rare earth leaching rates of 85.00%,90.00%and 95.00%were set.The results show that,after verifying the feasibility of the method through column leaching test,the actual leaching rates of the two kinds of ore samples can reach 85.93%,89.05%,94.22%and 85.97%,90.55%and 95.14%,respectively,which are within 1.5%of the target leaching rates.This method has good result in the laboratory and can be used to determine the dosage of ore leaching agent in the actual production.