Pyrolysis of crayfish waste and life cycle assessment of polygeneration process

A fast pyrolysis polygeneration system was investigated using crayfish shells as a resource for the utilization of solid wastes. Results showed that the bio-oil and the biochar accounted for 26 and 58 wt.% at a pyrolysis temperature of 600 degrees C, respectively. Heterocyclic compounds, specifically pyrrole and pyridine, were generated as the major nitrogen-containing products in the bio-oil. A life cycle assessment (LCA) demonstrated the environmental impact of the system was the lowest at 600 degrees C compared with that of other pyrolytic temperatures, with ADP of 881 MJ/t, GWP100 of 77.5 kg CO2 eq/t, POCP of -0.0128 kg C2H4 eq/t, AP of -0.0402 kg SO2 eq/t, and EP of 0.501 kg PO43-$$ {\mathbf{PO}}_{\mathbf{4}}<^>{\mathbf{3}-} $$ eq/t. Additionally, the cost amounted to 415.27 USD/t of biochar. The study opens a new pathway and insights to transform the shellfishery waste into biochar and platform chemicals efficiently and comprehensively.