|dc.description.abstract||The freshwater green microalgae strain Haematococcus pluvialis is the richest source for the production of natural astaxanthin. Astaxanthin is a pigment and member of the xanthophyll family of carotenoids that constitutes the highest value product derived by microalgae with a vast range of applications in the food, feed and pharmaceutical sector. So far, natural astaxanthin derived by microalgae amounts to <1% of the global market, since the synthetic alternative derived by petrochemicals involves lower production costs.
In this study, the technical and economic performance all through large scale production of natural astaxanthin, for two European cities (Livadeia, Greece and Amsterdam, the Netherlands) with different environmental conditions for cultivation, is investigated. The techno-economic assessment was facilitated by creating a process model, which simulated all phases of the production process. A hybrid system for photoautotrophic cultivation, comprising by a photobioreactor (PBR) for the ‘green’ stage and a raceway pond for the ‘red’ stage, was assumed. The area covered by the PBR and the raceway pond was assumed as 1 hectare respectively.
The technical part included the mass-energy flows during the production process. According to the results, the most important inflow in the system refers to freshwater. More specifically, 81662 (m3/year) and 34281 (m3/year) without recycling are needed for the production of 471 (kg/year) and 158 (kg/year) astaxanthin in Livadeia and Amsterdam respectively. The total energy needs were calculated at 494.8 (MWh/year) and 225.9 (MWh/year) for the Greek and the Dutch city respectively. This study investigated also the energy self-sufficiency of the production process by exploiting electricity generated by residual biomass gasification, after the pigment is recovered. It was found that only 12% for Livadeia and 9% for Amsterdam of the total energy needs were offset by residual biomass gasification.
As for economic performance, a Profit and Loss (P&L) analysis was conducted. The analysis involved the calculation of the CAPEX and annual OPEX that led to the determination of the return of investment (ROI) for different market prices of astaxanthin. It was found that only in Livadeia viability of a microalgae company can be achieved for all market prices. The costs for Livadeia and Amsterdam were calculated at €1122/kg and €3247/kg respectively, rendering only the Greek city as a decent site in order to compete with the synthetic alternative (costs of synthetic astaxanthin are €880/kg).||