Food processing wastewater purification by microalgae cultivation associated with high value-added compounds production - A review

Microalgac have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production. However, the high energy cost associated with complicated biorefinery (e.g. microalgae cultivation, harvesting, drying, extraction, conversion, and purification) is a critical challenge that inhibits its large-scale application. Among different nutrition (e.g. carbon, nitrogen and phosphorous) sources, food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity. In this review, the characteristic of different food wastewater is summarized and compared. The potential routes of value-added products (i.e. biofuel, pigment, polysaccharide, and amino acid) production along with wastewater purification are introduced. The existing challenges (e.g. biorefinery cost, efficiency and mechanism) of microalgal-based wastewater treatment are also discussed. The prospective of microalgae-based food processing wastewater treatment strategies (such as microalgae-bacteria consortium, poly-generation of bioenergy and value-added products) is forecasted. It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce, conversion and reutilization. (C) 2019 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co.,Ltd. All rights reserved.