Integrated techno-economic, investment risk and life cycle analysis of Indian lignocellulosic biomass valorisation via co-gasification and syngas fermentation

Abstract

The current work presents techno-economic and life cycle assessment of a co-gasification- fermentation hybrid model of bio-ethanol production with recycle and recovery of different resources. The model is also equipped with waste heat recovery from the hot syngas and power generation from unconverted syngas. The co-gasification process is based on Gibbs’ free energy minimization and syngas fermentation follows chemical equilibrium. With the objective of studying the economic feasibility and environmental sustainability of the proposed model, techno-economic assessment followed by financial risk analysis and life cycle analysis has been conducted. On the basis of 1 kg product bio-ethanol the results of the life cycle analysis, the present bio-ethanol production process have been compared to those of 1st generation ethanol production and biomass to bio-ethanol conversion via sugar platform. The present process is found to be economically viable with a net present value, internal rate of return and payback period of 18.7 M$, 13.33% and 6.7 years respectively. Monte Carlo simulation of financial risk has been modelled to predict the uncertainty over net present value and 81.8% is the probability of getting a non-negative net present value. Life cycle analysis suggest that the presented process emits 1.23 kg less CO2 per kg of bio-ethanol compared to the conventional bio-ethanol production process from biomass.