Bioinspired forward osmosis hydroponic system with an efficient hollow fiber assisted nutrient delivery system

This paper suggests a bio-inspired system that simultaneously addresses water and food shortages. In this system, saline water is desalinated using forward osmosis (FO) process to deliver fresh water to a hydroponic culture, without the need for recovery of draw agent. Inspiring from in-vivo blood vessel functionality within biological tissues, ultrafiltration hollow fiber membranes (HF) were exploited to deliver nutrients to plants without compromising FO driving force. A copolymer of N‑isopropylacrylamide and sodium acrylate hydrogel particles were used as both draw solution and hydroponic culture. As a proof of concept, cress and basil seeds were used as the model plant in the hydroponic culture. Although the low water flux of FO desalination process is known as its major drawback, here we take advantage of this low flux to design a new sustainable system to produce fresh water and grow plants. It was observed that the addition of seeds regardless of their type increases the water flux higher than that of hydrogel only. Also, the release of hydroponic nutrient from HFs is essential for the system to function. The parallel configuration of hollow fiber membranes with seeds placed adjacent to the fibers exhibited the best growth pattern.