Brine extraction for surface process and recovery of potash, lithium and industrial salt requires the application of traditional hydrogeological theories to hyper-saline solutions. Such brines present additional technical challenges in comparison to fresh water due to density effects, density driven multichemical composition flow on a large scale, and interaction between brines and fresh water over the course of the production period. Surface production facilities require estimation of brine composition over time. Therefore, the hydrogeologist is tasked to incorporate this features in all the project steps, including exploration and sampling plans, balancing extraction rates from multiple production wells, locating the production wells in space (and time), predicting chemical composition of the pre-pumping and extracted brines and monitoring depletion of a “dynamic” resource. Each of these parameters can have a significant impact on project economics. The parameters such as effective porosity, permeability, anisotropy, aquifer configuration (extent, thickness and heterogeneity), and wellfield efficiency are key in the estimation of resources and reserves for a brine extraction project. During the stages of prefeasibility and feasibility, an accurately built numerical groundwater model is required in order to develop a production plan.
This presentation examines the technical aspects of conducting a proper exploration campaign that will feed the precise parameters to the numerical groundwater model and therefore define a production plan and estimate extractable brine resources and reserves.
This presentation will also discuss the challenges and lessons learned from lithium brine projects in development in Argentina, from early exploration to production.
