Abstract The forward osmosis (FO)-reverse osmosis (RO) hybrid process is gaining attention in the desalination market because it can purify diluted seawater and the RO unit functions at low pressure conditions, resulting in a reduced total operational cost. However, FO element configuration affects the process performance, minimum flow rate, inlet pressure, product capacity, and draw solution (DS) dilution rate. Moreover, economic evaluation of the FO-RO hybrid process in the Middle East, which is the largest seawater desalination market, is required to obtain representative results. Realistic economic evaluation can be achieved with a real-performance database (DB) and specific assumptions. In this study, a techno-economic evaluation of the FO-RO hybrid process was conducted using real element-scale FO DB and simulation DB, and the results were compared with those of a stand-alone two stage RO process. Spiral wound FO (SWFO) and plate and frame (PFFO)-RO hybrid processes were more economical by 8.84% and 3.73%, respectively, when compared to two-stage RO. In the Middle East, the total cost of SWFO-RO was 45.1 M$ lesser than that of PFFO-RO due to its higher water flux and DS dilution rate. Therefore, the FO-RO hybrid process has high economic potential in the Middle East and elsewhere.

中文翻译：

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用于海水淡化的元素级正渗透-反渗透混合工艺的技术经济评价

摘要 正渗透 (FO)-反渗透 (RO) 混合工艺在海水淡化市场受到关注，因为它可以净化稀释的海水，并且 RO 单元在低压条件下运行，从而降低了总运营成本。但是，FO 元件配置会影响工艺性能、最小流速、入口压力、产品容量和汲取溶液 (DS) 稀释率。此外，中东是最大的海水淡化市场，需要对 FO-RO 混合工艺进行经济评估，以获得具有代表性的结果。可以通过真实性能​​数据库 (DB) 和特定假设来实现现实的经济评估。在这项研究中，使用真实元素规模的 FO DB 和模拟 DB 对 FO-RO 混合工艺进行了技术经济评估，并将结果与​​独立的两阶段 RO 过程的结果进行比较。与两级 RO 相比，螺旋缠绕 FO (SWFO) 和板框 (PFFO)-RO 混合工艺分别经济性高 8.84% 和 3.73%。在中东，由于其较高的水通量和 DS 稀释率，SWFO-RO 的总成本比 PFFO-RO 低 4510 万美元。因此，FO-RO 混合工艺在中东和其他地方具有很高的经济潜力。