Risk analysis of a supercritical fluid extraction plant through the phast & safeti software with extraction vessel rupture as scenario

In this work, a risk analysis of a supercritical fluid extraction plant is presented. The plant aims to extract valuable compounds from microalgae and uses carbon dioxide as a solvent at high temperature and pressure. Hazard events that could occur are related to the high pressure at which equipment operate and they, in addition to causing damage to the plant structure, could cause the release of CO2, which in high concentrations endangers the health of workers involved in the activities, therefore, an assessment of this type is crucial. The hazard scenario considered in this work is the equipment rupture. Generally, the rupture is analysed through methods based on indices determination such as the Fire and Explosion Index, the Probit analysis and the Safety Weighted Hazard Index. In this case, the commercial software “Phast & Safeti” of DNV GL Company was used, based on the modelling of the plant together with the process conditions definition. Among the equipment present in the plant, the extraction vessel was chosen since the extraction pressure of bioproducts is the highest in the plant and is equal to 500 bar. Risk parameters obtained after the analysis allow to select the most appropriate safety system able to limit the damage to structures and people.