Abstract Brine concentration is of critical importance in achieving zero liquid discharge in modern industrial processes. The effect of osmotic agent (OA) on the system performance in the treatment of different concentrations of brine using osmotic membrane distillation (OMD) was investigated. Significant improvement in water flux for concentrating the hypersaline brine was achieved compared to conventional membrane distillation processes. By altering the hydrodynamic conditions and using different combinations of feed streams and osmotic agents, a mathematical approach was applied, for the first time, to reveal the contribution of temperature and concentration polarization on flux enhancement in treating highly saline brines. This improvement was found to be caused mainly by the temperature polarization on the OA side of membrane, with less contribution from the decrease in vapor pressure of the bulk of the OA. This work illustrates that OMD is a promising process for efficient concentration of highly saline streams such as those found in the chlor-alkali industry. During the concentration of the spent brine from the electrolyte cell (NaCl concentration from 180 g/L to 310 g/L), OMD was shown to be the more cost and energy efficient compared to conventional MD processes.

中文翻译：

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渗透剂在渗透膜蒸馏 (OMD) 处理高盐盐水过程中增强水通量的作用

摘要 在现代工业过程中，盐水浓度对于实现零液体排放至关重要。研究了渗透剂 (OA) 在使用渗透膜蒸馏 (OMD) 处理不同浓度盐水时对系统性能的影响。与传统的膜蒸馏工艺相比，用于浓缩高盐盐水的水通量显着提高。通过改变流体动力学条件并使用进料流和渗透剂的不同组合，首次应用数学方法来揭示温度和浓差极化对处理高盐盐水通量增强的贡献。发现这种改进主要是由膜 OA 侧的温度极化引起的，大部分 OA 的蒸气压降低的贡献较小。这项工作表明 OMD 是一种有效浓缩高盐流（如氯碱工业中发现的流）的有前途的工艺。在浓缩电解槽废盐水期间（NaCl 浓度从 180 g/L 到 310 g/L），与传统 MD 工艺相比，OMD 显示出更高的成本和能源效率。