Although seawater reverse osmosis (RO) is nearing its thermodynamic minimum energy limit, it is still an energy-intensive process, requiring 2–3 kWh/m³ at a recovery of 50%. Pre-desalination of the seawater by reverse electrodialysis (RED), using an impaired water source, can further decrease this energy demand by producing energy and reducing the seawater concentration. However, RED is hampered by the initial high resistance of the fresh water source, resulting in a high required membrane area (i.e., high investment costs). In this paper, a new process is presented that can overcome this initial resistance and decrease the RED investment cost without the need for additional infrastructure: assisted RED (ARED). In ARED, a small potential difference is applied in the direction of the natural salinity gradient, increasing the ionic transport rate and rapidly decreasing the initial diluate resistance. This decreasing resistance is shown to outweigh any negative effects caused by, for example, concentration polarization, resulting in a process that is more efficient than theoretically expected. As this effect is mainly important at low diluate concentrations (up to 0.1 M), ARED is proposed as a first step in an economic and energy efficient (A)RED-RO hybrid process.

尽管海水反渗透（RO）接近其热力学最小能量极限，但它仍然是一个能源密集型过程，需要2–3 kWh /m³的能量才能达到50％的回收率。使用受损的水源，通过反向电渗析（RED）对海水进行预脱盐处理，可以通过产生能量并降低海水浓度进一步降低能源需求。然而，RED被淡水源的初始高阻力所阻碍，导致所需的膜面积高（即高投资成本）。在本文中，提出了一种新方法，该方法可以克服这种初始阻力并降低RED投资成本，而无需其他基础设施：辅助RED（ARED）。在ARED中，沿自然盐度梯度的方向施加了很小的电势差，增加离子传输速率并迅速降低初始稀释电阻。已显示出这种减小的电阻胜过例如由浓度极化引起的任何负面影响，从而导致该过程比理论上预期的效率更高。由于这种影响主要在低稀释液浓度（最高0.1 M）下很重要，因此建议将ARED作为经济高效且节能的（A）RED-RO混合工艺的第一步。