Industrial-scale biogas-to-hydrogen: Integrated steam biogas reforming–water-gas shift modeling and multi-objective optimization for energy-efficient hydrogen production

Steam biogas reforming (SBR) offers a renewable route to H 2 , yet most studies examine the reformer in isolation at lab-scale. This study develops a rigorous industrial-scale biogas-to-hydrogen framework that integrates a non-isothermal reformer, adiabatic water–gas shift (WGS) reactors, and auxiliary units (heaters, coolers, compressors, pumps, and adsorber). WGS kinetics are calibrated via data-driven parameter estimation and combined with pressure scale-up factors to ensure applicability under practical conditions. Parametric analysis quantifies the trade-off between H 2 production rate and specific energy consumption (SEC). A multi-objective optimization using NSGA-II generates a Pareto front of operating policies that captures this trade-off. Decision analysis with LINMAP and TOPSIS identifies a single compromise policy that increases H 2 production by 38.24% while raising SEC by only 3.11%. The framework provides system-level guidance for design and operation of biogas-to-hydrogen plants and supports commercialization toward carbon-neutral energy.