Environmental Resources Engineering Department, Humboldt State University , Arcata, California 95521, United States.
Environ Sci Technol. 2014 Jun 3;48(11):6437-43. doi: 10.1021/es405556s. Epub 2014 May 19.
A pilot system was designed and constructed to evaluate reverse osmosis (RO) energy reduction that can be achieved using pressure-retarded osmosis (PRO). The RO-PRO experimental system is the first known system to utilize energy from a volume of water transferred from atmospheric pressure to elevated pressure across a semipermeable membrane to prepressurize RO feedwater. In other words, the system demonstrated that pressure could be exchanged between PRO and RO subsystems. Additionally, the first experimental power density data for a RO-PRO system is now available. Average experimental power densities for the RO-PRO system ranged from 1.1 to 2.3 W/m2. This is higher than previous river-to-sea PRO pilot systems (1.5 W/m2) and closer to the goal of 5 W/m2 that would make PRO an economically feasible technology. Furthermore, isolated PRO system testing was performed to evaluate PRO element performance with higher cross-flow velocities and power densities exceeding 8 W/m2 were achieved with a 28 g/L NaCl draw solution. From this empirical data, inferences for future system performance can be drawn that indicate future RO-PRO systems may reduce the specific energy requirements for desalination by ∼1 kWh/m3.
设计并构建了一个中试系统，以评估可以通过压力延迟渗透（PRO）实现的反渗透（RO）能量减少。RO-PRO 实验系统是第一个已知的利用从大气压转移到半透膜另一侧的高压的水体积中的能量来预加压 RO 给料水的系统。换句话说，该系统证明了 PRO 和 RO 子系统之间可以交换压力。此外，现在可提供 RO-PRO 系统的第一个实验功率密度数据。RO-PRO 系统的平均实验功率密度范围为 1.1 至 2.3 W/m2。这高于以前的河流到海洋 PRO 中试系统（1.5 W/m2），更接近使 PRO 成为经济可行技术的 5 W/m2 的目标。此外，还进行了 PRO 系统的隔离测试，以评估 PRO 元件在更高的错流速度下的性能，使用 28 g/L 的 NaCl 汲取液可实现超过 8 W/m2 的功率密度。从这些经验数据中，可以得出对未来系统性能的推断，表明未来的 RO-PRO 系统可能会将脱盐的比能耗降低约 1 kWh/m3。
