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

ABSTRACT

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.

GRAPHICAL ABSTRACT

KEYWORDS:

• Forward osmosis
• cellulose acetate membrane
• vegetable liquor
• fertilizer draw solution

Acknowledgements

Jin Wang and Shuwei Zhao contributed to the paper equally.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Jin Wang and Shuwei Zhao contributed to the paper equally. The authors would like to thank the partial financial support from the National Natural Science Foundation of China (U1507117, 21676290) the Fundamental Research Funds for the Central Universities (18D311302) and Specialized Research Fund for the Doctoral Program of Senior Education of China (grant NO. 20130075110006).