Effect of organic carbon to nitrogen ratio in wastewater on growth, nutrient uptake and lipid accumulation of a mixotrophic microalgae Chlorella sp. (June 2019)

• Record Type: Journal Article
• Authors: Gao, Feng; Yang, Hong-Li; Li, Chen; Peng, Yuan-Yuan; Lu, Miao-Miao; Jin, Wei-Hong; Bao, Jing-Jiao; Guo, Yuan-Ming
• Is Part Of: Bioresource technology. Volume 282(2019)
• Page Start: 118
• Page End: 124
• Publication Date: 2019-06
• Subjects: Microalgae -- Wastewater -- Organic carbon -- Mixotrophic culture -- Nutrient removal; 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.2019.03.011
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: A mixotrophic microalgae Chlorella sp. G-9 was separated from a WWTP. Increasing TOC/TN ratio of wastewater promoted algal growth and nutrient removal. Growth rate of microalgae did not increase as TOC/TN ratio increased from 24 to 30. 99.58% and 99.61% nitrogen was removed in the wastewaters with TOC/TN of 24 and 30. The highest lipid content of 36.5% was achieved in wastewater with TOC/TN of 30. Abstract: This study investigated the biomass/lipid production, nutrient removal and fatty acid composition of an isolated mixotrophic microalga ( Chlorella sp. G-9) cultured in simulated wastewater with different TOC/TN ratio. As the TOC/TN ratio of wastewater increased from 0 to 24, the growth rate of Chlorella sp. G-9 increased gradually, but did not increase further at 30. Nutrient removal was related to microalgae growth. In the wastewater with TOC/TN ratio of 24 and 30, 99.58% and 99.61% nitrogen was removed, respectively. In conditions of initial TOC/TN ratios of 24 and 30, Chlorella sp. G-9 could accumulate lipid as high as 35.3% and 36.5%, respectively. The corresponding lipid productivities were 34.2 and 32.6 mg L −1 d −1, respectively, which were 13.7 and 13.0 times higher than those in photoautotrophic condition. Increasing the initial TOC/TN ratio of the wastewater could slightly increase the saturated degree in fatty acid, thereby improving the stability of biodiesel.