Abstract Pressure retarded osmosis (PRO) has been considered as a potential technique to harvest salinity gradient energy (or osmotic energy). The SWRO-PRO hybrid system is one of the viable ways of implementing PRO technology to resolve problems associated with seawater desalination. However, relatively few works have been attempted in pilot scales, which are inevitable for the scale-up and practical application of the SWRO-PRO technology. In this context, this paper reports the pilot study results of SWRO-PRO hybrid system (240 m3/day). To examine the long-term performance, the plant was operated for more than 2 years. The flux and energy consumption in the plant were analyzed to examine the potential of PRO as a secondary energy recovery device. The fouling propensity of the PRO membranes was examined. Results showed that the use of PRO can reduce the energy consumption of SWRO process by approximately 20%. Moreover, the SWRO brine was diluted up to 63%. This work will provide an insight into the researchers and scientific community by filling the gap between the bench-scale works and the commercial-scale application.

中文翻译：

---

海水反渗透 (SWRO) – 压力延迟渗透 (PRO) 混合系统的扩大规模：以 240 立方米/天的中试工厂为例

摘要 压力延迟渗透 (PRO) 已被认为是一种获得盐度梯度能量（或渗透能）的潜在技术。SWRO-PRO 混合系统是实施 PRO 技术以解决与海水淡化相关的问题的可行方法之一。然而，在中试规模上尝试的工作相对较少，这对于 SWRO-PRO 技术的放大和实际应用是不可避免的。在此背景下，本文报告了 SWRO-PRO 混合系统（240 m3/天）的试点研究结果。为了检查长期性能，该工厂运行了 2 年多。对工厂中的通量和能源消耗进行了分析，以检验 PRO 作为二次能源回收设备的潜力。检查了 PRO 膜的结垢倾向。结果表明，使用PRO可以将SWRO工艺的能耗降低约20%。此外，SWRO 盐水稀释至 63%。这项工作将通过填补实验室规模工作和商业规模应用之间的空白，为研究人员和科学界提供深入的了解。