Industrial bio-fractionation process of microalgae valuable products using supercritical {CO}2. A techno-economical evaluation

This work shows how Omega-3 triglycerides and carotenoids can be produced industrially from the microalga Chlorella vulgaris by fractionating extraction employing supercritical CO2, also estimating the relevant costs. One key point is that the devised process separates triglycerides from carotenoids. The estimates have been carried out by modelling both triglycerides and carotenoids extraction and purification, by quantifying the overall process material and heat balance and required operating conditions with the aid of a process simulation spreadsheet. The results showed separate streams of 138.3 kg per day of triglycerides and 8.4 kg per day of carotenoids can be obtained from a daily feed of 360 kg of freeze-dried microalga. In addition, an estimation of Operating Expense (OPEX) and Capital Expenditure (CAPEX) was carried out obtaining, respectively, 1050 k€/y and 3699 k€. The developed integrated process shows, in terms of costs and product quality, a significant improvement respect to previous works, underlying its feasibility for industrial applications.