Sustainable biohythane production from algal bloom biomass through two-stage fermentation: Impacts of the physicochemical characteristics and fermentation performance. (4th December 2020)

• Record Type: Journal Article
• Authors: Chen, Cheng; Sun, Chihe; Xia, Ao; Liao, Qiang; Guo, Xiaobo; Huang, Yun; Fu, Qian; Zhu, Xianqing; Zhu, Xun
• Is Part Of: International journal of hydrogen energy. Volume 45:Number 59(2020)
• Page Start: 34461
• Page End: 34472
• Publication Date: 2020-12-04
• Subjects: Bloom algae -- Hythane -- Fermentation -- Hydrothermal pre-treatment -- Sustainable gaseous biofuel; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.02.027
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Algal bloom biomass, sourced from a freshwater lake in Chongqing, was pre-treated by hydrothermal pre-treatments with or without acid/alkali catalysts, and subsequently used as a substrate for sustainable biohythane production via fermentation. Fourier transform infrared (FTIR) spectroscopy analyses suggested hydrothermal acid/alkali pre-treatments significantly changed peak intensities of chemical compositions in algal bloom biomass. Derivative thermogravimetric (DTG) analyses showed more macromolecular substances hydrolysed after hydrothermal acid/alkali pre-treatments. When bloom algae were pre-treated with 1% HCl at 140 °C for 10 min, an optimal specific hydrogen yield (SHY) of 39.4 mL/g volatile solid (VS) was obtained, which is 38.2% higher than raw biomass. However, a 34.4% decrease in SHY occurred under hydrothermal pre-treatment with 1% NaOH due to the enhancement of Maillard reaction. When using the effluents in methane fermentation, specific methane yields (SMYs) were 177.1–276.8 mL/g VS. Two-stage process effectively reduced the total fermentation time by 22.7% compared with single-stage fermentation. Highlights: Bloom algae under various pre-treatments was used for biohythane fermentation. Physiochemical characteristics of biomass before and after treatment were analysed. Optimal SHY of 39.4 mL/g VS was obtained from hydrothermal acid pre-treatment. 34.4% decrease in SHY occurred when pre-treated with hydrothermal alkali. Fermentation time of two-stage process was 22.7% less than single-stage process.