Simultaneous enhancing the sedimentation and adsorption performance of Chlorella vulgaris with montmorillonite modified cationic starch

摘要

For micmalgae flocculation, the main drawback is high time consumption caused by low flocs settling velocity, thus, enhancing the sedimentation performance is an urgent problem in need of a solution. To enhance the settling velocity of microalgae flocs, montmorillonite clay was applied to microalgae flocculation in the form of flocculant carrier in this study. With clay, the effective density of micmalgae flocs was enhanced remarkably. When the dry weight ratio of clay to cationic starch was 2, the effective density of microalgae flocs was 3.15-fold of that without clay. As a result, the settling velocity of microalgae flocs was enhanced 2.34 times. Additionally, owing to the tear effect of clay and well distribution of cationic starch, the mean diameter of generated flocs was slightly reduced and micmalgae harvesting efficiency was improved. All these results suggested that the montmorillonite clay promises to be an ideal candidate for micmalgae flocculation that can both enhance the microalgae sedimentation and adsorption performance.