Chlorella vulgaris cultivation in pilot-scale to treat real swine wastewater and mitigate carbon dioxide for sustainable biodiesel production by direct enzymatic transesterification. (April 2022)

• Record Type: Journal Article
• Authors: Xie, Dian; Ji, Xiaowei; Zhou, Youcai; Dai, Jingxuan; He, Yongjin; Sun, Han; Guo, Zheng; Yang, Yi; Zheng, Xing; Chen, Bilian
• Is Part Of: Bioresource technology. Volume 349(2022)
• Publication Date: 2022-04
• Subjects: Chlorella vulgaris -- Real swine wastewater -- Nutrients removal -- CO2 mitigation -- Enzymatic transesterification -- Biodiesel; 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.2022.126886
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Chlorella vulgaris was used to treat real swine wastewater and fix carbon dioxide. Experiments were conducted under outdoor conditions in 5-m 3 open raceway ponds. Microalga at 3% CO2 had better features in growth, CO2 fixation and nutrients removal. Enzymatic transesterification by TL and PLA attained the highest biodiesel conversion. The process addressed wastewater treatment, CO2 mitigation and biodiesel production. Abstract: This study firstly addressed real swine wastewater (RSW) treatment by an indigenous Chlorella vulgaris MBFJNU-1 in 5-m 3 outdoor open raceway ponds and then direct enzymatic transesterification of the resulting lipids from the wet biomass for sustainable biodiesel production. Compared to the control group, C. vulgaris MBFJNU-1 at 3% CO2 achieved higher microalgal biomass (478.5 mg/L) and total fatty acids content (21.3%), higher CO2 bio-fixation (63.2 mg/L/d) and lipid (9.1 mg/L/d) productivities, and greater nutrients removals (total nitrogen, 82.1%; total phosphorus, 28.4%; chemical oxygen demand, 37.1%). The highest biodiesel conversion (93.3%) was attained by enzymatic transesterification of wet disrupted Chlorella biomass with 5% lipase TL and 5% phospholipase PLA. Moreover, the enzymatic transesterification gave around 83% biodiesel conversion in a 15-L stirred tank bioreactor. Furthermore, the integrated process was a cost-effective approach to treat RSW and mitigate CO2 for microalgal biodiesel production, based on the mass and energy balances analysis.