Pyrolysis of crayfish waste and life cycle assessment of polygeneration process

Abstract

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°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°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 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.