Supercritical extraction of grape seed oil at industrial-scale: Plant and process design, modeling, economic feasibility

The aim of this paper is to present the results of a study on the possible use of exhausted grape marc for obtaining grape seed oil by means of the supercritical technology. An industrial-scale supercritical extraction plant (three extractors in series working in the counter-current mode) has been designed based on the availability of grape seeds of a region in the north of Italy, namely 3000 ton/year (3 × 106 kg/year). The process has been analyzed in depth and modeled and the results indicate that the proposed industrial application could be economically interesting: the breakeven point, which makes the process economically sustainable, is a value of 5.9 €/kg for the supercritical extracted grape seed oil.The results obtained are of international interest considering the volume of the worldwide production of exhausted grape marc. Moreover, specific costs and incomes linked to the supercritical technology are reported in details for the case study and could be of reference when dealing with similar processes.