Biorefining of microalgae: from harvesting to biofuel production

Identifier:  TDX:2834

Handle: https://hdl.handle.net/20.500.11797/TDX2834

Authors:  Haponska, Monika

Abstract:
his thesis focuses on the modernization of the downstream process of microalgae biorefining by membrane technology. The project concerns the optimization of: harvesting, cell disruption, carbohydrates, proteins and lipids fractionation and development of catalytic membrane reactor for transesterification to obtain biodiesel. Cost reduction of the overall process can be achieved by finding cheaper solutions for each step. In the first stage the filtration using own-made ABS polymeric membranes as well as the commercially available ones was run to check their performance for microalgae dewatering. This study included ABS membranes preparation and characterization using different techniques. Also, the comparison of two filtration methods, cross-flow and dynamic was performed to compare the viability of membranes affected by a fouling and a cake formation. In a second stage, the pilot scale dewatering of two microalgae specie, Chlorella sorokiniana and Dunaliella tertiolecta by sedimentation followed by dynamic filtration was performed. The objective of the combined process was to reduce microalgae dewatering costs since sedimentation offers a very cheap operation and membrane filtration offers total rejection with high final concentrations at a lower cost than centrifugation. In a third stage cell disruption and fractionation for lipids, sugars and proteins recovery was studied. Acid-catalysedT