Abstract Many industrial and agricultural applications require the treatment of water streams containing high concentrations of ionic species for closing material cycles. High concentration factors are often desired, but hard to achieve with established thermal or membrane-based water treatment technologies at low energy consumptions. Capacitive deionization processes are normally assumed as relevant for the treatment of low salinity solutions only. Flow-electrode capacitive deionization (FCDI), on the other hand, is an electrically driven water desalination technology, which allows the continuous desalination and concentration of saline water streams even at elevated salinities. Ions are adsorbed electrostatically in pumpable carbon flow electrodes, which enable a range of new process designs. In this article, it is shown that continuously operated FCDI systems can be applied for the treatment of salt brines. Concentrations of up to 291.5 g/L NaCl were reached in the concentrate product stream. Based on this, FCDI is a promising technology for brine treatment and salt recovery. Additionally, a reduction of the energy demand by >70% is demonstrated by introducing multiple cell pairs into a continuous FCDI system. While the economic feasibility is not investigated here, the results show that FCDI systems may compete with established technologies regarding their energy demand.

中文翻译：

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流动电极电容去离子实现连续和节能的盐水浓缩

摘要 许多工业和农业应用需要处理含有高浓度离子物质的水流，以关闭材料循环。高浓缩系数通常是需要的，但很难以低能耗的成熟热或基于膜的水处理技术实现。通常假设电容去离子过程仅与低盐度溶液的处理相关。另一方面，流动电极电容去离子 (FCDI) 是一种电力驱动的水淡化技术，即使在盐度较高的情况下，它也可以连续淡化和浓缩咸水流。离子被静电吸附在可泵送的碳流动电极中，这使得一系列新的工艺设计成为可能。在本文中，结果表明，连续运行的 FCDI 系统可用于处理盐水。在浓缩产品流中达到了高达 291.5 g/L NaCl 的浓度。基于此，FCDI 是一种很有前途的盐水处理和盐回收技术。此外，通过将多个电池对引入连续 FCDI 系统，证明了能源需求减少了 70% 以上。虽然这里没有调查经济可行性，但结果表明 FCDI 系统可能会在能源需求方面与现有技术竞争。通过将多个电池对引入连续 FCDI 系统，证明了能源需求减少了 70% 以上。虽然这里没有调查经济可行性，但结果表明 FCDI 系统可能会在能源需求方面与现有技术竞争。通过将多个电池对引入连续 FCDI 系统，证明了能源需求减少了 70% 以上。虽然这里没有调查经济可行性，但结果表明 FCDI 系统可能会在能源需求方面与现有技术竞争。