Biomethanol production from landfill biogas: A techno-economic comparison of different potential pathways with real landfill biogas feed data for a production plant in South-Spain

The production of biomethanol from landfill biogas represents a promising pathway for renewable applications, yet its economic feasibility remains a critical challenge. Herein we present a novel study aimed at conducting a techno-economic analysis to obtain biomethanol out of a landfill biogas produced in South-Spain. Four production pathways are evaluated: (i) dry reforming as a baseline case; (ii) a syngas upgrading route via reverse water–gas shift; (iii) green hydrogen feed to yield more biomethanol; and (iv) tri-reforming based on steam produced within the process and oxygen from the biogas itself. By this, a more realistic approach to a higher value-added utilization of landfill biogas is demonstrated to be viable. Process simulations were conducted in Aspen Plus, and economic performance was assessed in Excel through Net Present Value (NPV) and Minimum Selling Price (MSP) as key indicators. Results prove that tri-reforming technology significantly increases biomethanol production while slightly increasing material costs, thus achieving a competitive MSP value of 0.86€/kg with a positive NPV compared to green hydrogen (MSP = 0.95€/kg), reverse water–gas shift (MSP = 1.16€/kg) and dry reforming (MSP = 1.39€/kg). Sensitivity analysis highlights the influence of reforming heating and labour expenses on economic performance. This study sheds light on the existing literature missing case studies based on real feed biogas conditions, a gap that needs to be addressed since the future sustain of producing biomethanol will largely depend on accurate assessments to process biogas.