Techno-economic and environmental assessment of shrimp waste biorefinery routes

The rapid growth of aquaculture, particularly shrimp farming, has generated large quantities of waste (heads, shells, and exoskeletons), which represent both an environmental liability and an opportunity for resource valorization. This waste is rich in valuable compounds such as chitin, astaxanthin, proteins, and lipids, whose recovery within a biorefinery concept enables their valorization. Although there is extensive literature on methodologies for extracting products derived from shrimp shells, the topic remains underexplored in the field of Process Engineering. Furthermore, the ideal technological configurations for large-scale implementation remain unclear. Therefore, this study modeled and compared multiple technological routes for the valorization of shrimp waste, evaluating their technical and economic performance using standard indicators typically applied in early-stage industrial process evaluations. The results showed that integrated biorefineries targeting multiple high-value bioproducts maximized industrial viability. Among them, chitin oligomers exhibited the highest profitability, with return on investment values exceeding 40% and Net Present Values approaching US$20 million under certain assumptions, even at moderate production scales. From an environmental perspective, the most profitable routes generally exhibited higher water and energy demands; however, Brazil's low-carbon electricity matrix significantly reduced their global warming potential. In contrast, solvent-intensive routes showed higher environmental impacts, highlighting the importance of process integration, solvent selection, and efficient utility management. Overall, the results highlight the strategic importance of integration and high-value targeting for sustainable shrimp biorefineries, while future work should explore optimization frameworks to enhance economic and environmental performance.