In base metal refineries Na₂SO₄ is produced in large quantities as a neutralization salt and recovered via energy intensive evaporative crystallization. Splitting the Na₂SO₄ brine into its three components NaOH, H₂SO₄ and process water via electrodialysis using a bipolar membrane (EDBM) in combination with reverse osmosis (RO) was investigated as an alternative solution.

Process phenomena such as non-ideal membrane behavior and electro-osmosis were investigated at the high concentration levels occurring in a metal refinery using synthetic Na₂SO₄ solutions. Subsequently, operating conditions were optimized. It was found that a determining factor in minimizing the splitting cost is the salt concentration that should be kept in the 100–150 g Na₂SO₄/L range to maintain a high current density. To maintain a high feed concentration, the EDBM was combined with a Disk Reverse Osmosis (DRO) unit to re-concentrate the partially depleted salt solution.

The techno-economic analysis of a 100 kg Na₂SO₄/h demonstration plant shows that the production cost of NaOH, which is the most valuable of the three products, is in the range of the bulk NaOH price. All three products are reused in the metal refinery making the EDBM-DRO plant a Zero Brine solution to prevent salinization in in-land mining areas.

在贱金属精炼厂中，大量生产Na ₂ SO ₄作为中和盐，并通过能量密集的蒸发结晶进行回收。研究了使用双极膜（EDBM）结合反渗透（RO）通过电渗析将Na ₂ SO ₄盐水分为NaOH，H ₂ SO ₄和工艺水三部分的做法，并将其作为替代解决方案。

使用合成的Na ₂ SO ₄溶液，在金属精炼厂中发生的高浓度水平下，研究了诸如非理想膜行为和电渗等过程现象。随后，对运行条件进行了优化。发现将分离成本最小化的决定因素是盐浓度，应将盐浓度保持在100–150 g Na ₂ SO ₄ / L范围内以保持高电流密度。为了保持较高的进料浓度，将EDBM与圆盘反渗透（DRO）单元结合使用，以重新浓缩部分耗尽的盐溶液。

对一个100千克Na ₂ SO ₄ / h示范工厂的技术经济分析表明，这三种产品中最有价值的NaOH生产成本在整体NaOH价格范围内。所有这三种产品都在金属精炼厂中重复使用，从而使EDBM-DRO工厂成为零卤水解决方案，以防止内陆矿区盐碱化。