Theoneste Ndikubwimana1, Xianhai Zeng2, Theophile Murwanashyaka1, Emmanuel Manirafasha1, Ning He3, Wenyao Shao1, Yinghua Lu3. 1. Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, China. 2. College of Energy, Xiamen University, 361005 Xiamen, China ; The Key Laboratory for Synthetic Biotechnology of Xiamen City, Xiamen University, 361005 Xiamen, China. 3. Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, China ; The Key Laboratory for Synthetic Biotechnology of Xiamen City, Xiamen University, 361005 Xiamen, China.
Abstract
BACKGROUND: Nowadays, bioflocculation is considered as a potential technology that could be able to alleviate microalgae dewatering cost regarded as the cornerstone hindrance of their full-scale application. However, most bioflocculation studies reported are laboratory scales. This study examined a pilot-scale and in situ flocculation of freshwater microalgae Desmodesmus brasiliensis by microbial bioflocculant. Biochemical composition of microalgal biomass was analyzed to evaluate the applicability of bioflocculation for microalgae-based biofuel production. RESULTS: The flocculation efficiency >98 % was achieved at both pilot-scale and in situ treatment. Bioflocculation is simple, effective, economic, and environmentally friendly. Even though total proteins recovered from biomass harvested by centrifugation and that harvested by bioflocculation were significantly different, there was no significant difference in total carbohydrates and total lipids recovered from either biomass harvested by centrifugation or biomass harvested by bioflocculation. CONCLUSION: The results herein presented, doubtlessly demonstrated that the γ-PGA bioflocculant produced by Bacillus licheniformis CGMCC 2876 is applicable for commercial-scale microalgae harvesting. In addition, bioflocculation process cost could greatly be reduced by in situ operation as no investment cost is needed for a separate flocculation tank and mixing device. Furthermore, bioflocculation method developed is a worthy microalgae harvesting method for algal-based biofuel production.Graphical abstractThe addition of bioflocculant to microalgae cultures followed by mixing elicits, the formation of heavy flocs which settle out by gravity sedimentation in a relatively short settling time.
BACKGROUND: Nowadays, bioflocculation is considered as a potential technology that could be able to alleviate microalgae dewatering cost regarded as the cornerstone hindrance of their full-scale application. However, most bioflocculation studies reported are laboratory scales. This study examined a pilot-scale and in situ flocculation of freshwater microalgae Desmodesmus brasiliensis by microbial bioflocculant. Biochemical composition of microalgal biomass was analyzed to evaluate the applicability of bioflocculation for microalgae-based biofuel production. RESULTS: The flocculation efficiency >98 % was achieved at both pilot-scale and in situ treatment. Bioflocculation is simple, effective, economic, and environmentally friendly. Even though total proteins recovered from biomass harvested by centrifugation and that harvested by bioflocculation were significantly different, there was no significant difference in total carbohydrates and total lipids recovered from either biomass harvested by centrifugation or biomass harvested by bioflocculation. CONCLUSION: The results herein presented, doubtlessly demonstrated that the γ-PGA bioflocculant produced by Bacillus licheniformis CGMCC 2876 is applicable for commercial-scale microalgae harvesting. In addition, bioflocculation process cost could greatly be reduced by in situ operation as no investment cost is needed for a separate flocculation tank and mixing device. Furthermore, bioflocculation method developed is a worthy microalgae harvesting method for algal-based biofuel production.Graphical abstractThe addition of bioflocculant to microalgae cultures followed by mixing elicits, the formation of heavy flocs which settle out by gravity sedimentation in a relatively short settling time.
Entities:
Keywords:
Biochemical composition; Bioflocculant; In situ flocculation; Microalgae; Pilot scale
Authors: Nicholas B Wyatt; Lindsey M Gloe; Patrick V Brady; John C Hewson; Anne M Grillet; Matthew G Hankins; Phillip I Pohl Journal: Biotechnol Bioeng Date: 2011-09-09 Impact factor: 4.530
Authors: Lieve M L Laurens; Thomas A Dempster; Howland D T Jones; Edward J Wolfrum; Stefanie Van Wychen; Jordan S P McAllister; Michelle Rencenberger; Kylea J Parchert; Lindsey M Gloe Journal: Anal Chem Date: 2012-02-08 Impact factor: 6.986