The discharge of wastewater from the mining industry has a critical ecological impact, potentially endangering both soil and marine ecosystems. Alternatively, recovering pure water and valuable materials from these hypersaline streams through a technologically efficient process, would help reduce the ecological impact of the waste, while providing a viable supply chain for raw materials such as magnesium, potassium and others, considered critical to the economy. In this context, this work aimed to simultaneously recover pure water and mineral salts from mine wastewater by membrane-assisted crystallization (MAC). A prior theoretical study based on thermodynamic parameters attempted to predict salts precipitation at different temperatures. MAC tests were then performed at specific thermal gradients and feed pretreatment conditions, achieving preferential precipitation of solids products of different composition containing large quantities of Ca or Mg/K minerals from the real mine tailing wastewater. The experiments also demonstrated the central impact of heterogeneous nucleation effects.

采矿业排放的废水对生态有重大影响，可能危及土壤和海洋生态系统。或者，通过技术高效的工艺从这些高盐流中回收纯水和有价值的材料，将有助于减少废物对生态的影响，同时为镁、钾和其他被认为对经济至关重要的原材料提供可行的供应链。在此背景下，这项工作旨在通过膜辅助结晶 （MAC） 同时从矿山废水中回收纯水和矿物盐。先前基于热力学参数的理论研究试图预测不同温度下的盐析出。然后在特定的热梯度和进料预处理条件下进行 MAC 测试，实现从真实矿山尾矿废水中含有大量 Ca 或 Mg/K 矿物的不同成分的固体产品的优先沉淀。实验还证明了异质成核效应的核心影响。