Sustainable fertilizer-drawn forward osmosis for the vegetable industry in reducing liquor from vegetable waste

Forward osmosis has been widely used due to its advantages such as low energy consumption and low membrane fouling. Conventional treatment of vegetable industry wastes leaving the liquor an additional puzzle. The objective of this study is to evaluate the feasibility of reducing energy consumption by using forward osmotic membrane technology to concentrate vegetable liquor. In this research, the suitable draw solutes' condition was investigated, results showed 1 M ammonium sulphate could reach 7.21 LMH water flux and it was chosen as the draw solution for concentrating vegetable liquor, then the long-term FO performance was compared with theoretical water flux showing that the difference of water flux decrease is caused by the organic matter. Further identification of the major foulant via a control variable method using simulated vegetable liquor leads to anthocyanins as the major foulant. This novel application of the fertilizer drawn FO process provided an environmentally friendly solution to the vegetable industry, which would potentially transform an industry into a sustainable cyclic economy.