Lipid Extraction Process Design

A basis of 90% total lipid recovery is assumed for design calculations. Using the proximal composition in Fig. 3 , the annual yield of oil from P. tricornutum with 90% recovery is ~9,000 tonnes. However, this amount could reduce when the extract is purified and all unsaponifiable components are removed. The design is focussed on the use of solvent extraction on wet biomass with no cell lysis unit operation. Lee et al. [17] demonstrated that cell lysis before solvent extraction does not significantly affect lipid yield. This extraction method is employed due to its high lipid yields and minimal extraction steps. It also involves the use of low-solvent quantities. The total amount of saponifiable lipids extracted from P tricornutum is approximately 6.4% of biomass (dry weight) [27]. Therefore, the daily yield of purified lipid from the extraction is approximately 7.78 tonnes. Figures 6 and 7 show the product yields from the crude lipid extraction and purification processes.

Fig. 7 Inputs and output flows from algal crude lipid purification