Designing a Vapour-Compression Cascade Refrigeration Setup Aimed at Storing Fresh Plasma

Throughout the duration of the COVID-19 pandemic, human plasma emerged as a primary resource for various therapeutic transfusions, leveraging its protein content as an alternative treatment for infectious ailments. Cascade refrigeration systems, with their capability for ultra-low temperature applications and convenient storage, have emerged as a compelling and highly efficient innovation. This study presents the creation of a portable vapor-compression refrigeration system designed for the handling of blood products at collection points. To capitalize on their superior thermodynamic properties, operational fluid mixtures comprising R410A and R404A were chosen. The system underwent testing both without load and under varying load conditions, with its viability, consistency, and repeatability assessed using animal blood plasma. The process of converting different masses of freshly harvested plasma to refrigerated plasma at -35°C took varying durations, ranging from 120 to 190 minutes. Importantly, the nutritional and biological integrity of the plasma remained unaltered post-freezing. Specific values obtained include pre-albumin levels of 19.2/12.6 mg/dl, albumin levels of 35.2/42.2 g/dl, protein levels of 85.7/82.4 g/dl, fibrinogen levels of 3.30 g/dl, and globulin levels of 36.9 g/dl, respectively. Performance evaluation of the system revealed a cooling effect of 79.5% equating to 186.40 kJ/kg, a coefficient of performance (COP) of 3.57, and an isentropic efficiency of 44.6%. This developed device addresses the challenges posed by heat-sensitive medications in regions with limited power resources, potentially saving countless lives and conserving 3942 MJ of energy, rendering it economically feasible even in affluent nations.