Marine Energy Convergence and Integration Laboratory, Jeju Global Research Center (JGRC), Korea Institute of Energy Research (KIER), 200, Haemajihaean-ro, Gujwa-eup, 63357, Jeju, South Korea.
Marine Energy Convergence and Integration Laboratory, Jeju Global Research Center (JGRC), Korea Institute of Energy Research (KIER), 200, Haemajihaean-ro, Gujwa-eup, 63357, Jeju, South Korea.
Water Res. 2019 Nov 15;165:114970. doi: 10.1016/j.watres.2019.114970. Epub 2019 Aug 10.
To properly design reverse electrodialysis (RED) stacks, modeling of ion transport and prediction of power generation on the single RED stack are very important. Currently, the Nernst-Planck equation is widely adopted to simulate ion transport through IEMs. However, applying typical Nernst-Planck equation is not proper to analyze ion transport through the heterogeneous thin-composite pore-filling membrane because of the non-conductive site in the membrane matrix. Herein, we firstly introduced modified Nernst-Planck equation by addressing conductive traveling length (CTL) to simulate the ion transport through the thin-composite pore-filling membranes and the performance of a single RED stack with the same membranes. Also, 100 cell-pairs of RED stacks were assembled to validate modified Nernst-Planck equation according to the flow rate and membrane types. Under the OCV condition, the conductivity of the effluents was measured to validate the modified Nernst-Planck equation, and differences between modeling and experiments were less than 1.5 mS/cm. Theoretical OCV and current density were estimated by using modified Nernst-Planck equation. In particular, hydrophobicity on the surface of the heterogeneous membrane was considered to describe ion transport through the pore-filling membranes. Moreover, power generation from RED stacks was calculated according to the flow rate and the number of cell pairs.
为了正确设计反向电渗析（RED）堆栈，对离子传输进行建模以及对单个 RED 堆栈的发电能力进行预测非常重要。目前，广泛采用能斯特-普朗克方程来模拟通过 IEM 的离子传输。然而，由于膜基质中的非导电位，应用典型的能斯特-普朗克方程来分析通过异质薄复合孔填充膜的离子传输是不合适的。在此，我们首先通过解决传导行进长度（CTL）来引入修正的能斯特-普朗克方程，以模拟通过薄复合孔填充膜的离子传输以及具有相同膜的单个 RED 堆栈的性能。此外，根据流量和膜类型组装了 100 个电池对的 RED 堆栈来验证修正的能斯特-普朗克方程。在 OCV 条件下，测量了流出物的电导率以验证修正的能斯特-普朗克方程，模型与实验之间的差异小于 1.5 mS/cm。通过使用修正的能斯特-普朗克方程来估计理论 OCV 和电流密度。特别是，考虑了异质膜表面的疏水性以描述通过孔填充膜的离子传输。此外，根据流量和电池对的数量计算了 RED 堆栈的发电能力。
