The energy recovery potential of industrial hemp pressing cake (Cannabis sativa L. ) is studied using a full Life Cycle Assessment (LCA), implemented in the open-source software openLCA v2. 4 and coupled to the ecoinvent 3. 10 database (cut-off system). Two processes are compared: (I) combined heat and power (CHP) cogeneration (direct combustion, ηₑ=25%, ηₜh=55%) and (II) anaerobic digestion (AD, BMP up to 248 NmL CH4/g VS). The ReCiPe 2016 Midpoint (H) impact method, combined with the IPCC’s GWP100 factors, allows for the quantification of environmental impacts according to the system expansion (substitution) method. The results show that CHP, by substituting electricity from Morocco’s high-carbon electricity mix (approximately 650 gCO2eq/kWh), achieves a net Global Warming Potential (GWP) of -520 kgCO2eq per ton of treated waste. Anaerobic digestion, on the other hand, is only environmentally competitive if CH4 leaks are kept below 3. 5%. Finally, a substitution modeling module (polynomial approximation) enables multi-objective optimization of operating parameters, revealing that humidity control (less than 10% for combustion) and total heat recovery from the CHP system are the priority levers for action.
Labjouj et al. (Wed,) studied this question.