A novel cleaner production process of citric acid by recycling its treated wastewater. (July 2016)

• Record Type: Journal Article
• Authors: Xu, Jian; Su, Xian-Feng; Bao, Jia-Wei; Zhang, Hong-Jian; Zeng, Xin; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui
• Is Part Of: Bioresource technology. Volume 211(2016)
• Page Start: 645
• Page End: 653
• Publication Date: 2016-07
• Subjects: Citric acid -- Methane -- Anaerobic digestion -- Air stripping -- Electrodialysis; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2016.03.163
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: A novel cleaner production process of citric acid was proposed. Citric acid wastewater was treated with anaerobic digestion to produce methane. Air stripping and electrodialysis treatment of digestate were efficient. Citrate production using treated digestate was comparable to that with tap water. This process could minimize wastewater discharge and water consumption. Abstract: In this study, a novel cleaner production process of citric acid was proposed to completely solve the problem of wastewater management in citric acid industry. In the process, wastewater from citric acid fermentation was used to produce methane through anaerobic digestion and then the anaerobic digestion effluent was further treated with air stripping and electrodialysis before recycled as process water for the later citric acid fermentation. This proposed process was performed for 10 batches and the average citric acid production in recycling batches was 142.4 ± 2.1 g/L which was comparable to that with tap water (141.6 g/L). Anaerobic digestion was also efficient and stable in operation. The average chemical oxygen demand (COD) removal rate was 95.1 ± 1.2% and methane yield approached to 297.7 ± 19.8 mL/g TCODremoved . In conclusion, this novel process minimized the wastewater discharge and achieved the cleaner production in citric acid industry.