Evaluation of on-site hydrogen generation via steam reforming of biodiesel: Process optimization and heat integration

Abstract

The present simulation study investigates on-site hydrogen generation (50 Nm3/h) via steam reforming of biodiesel. The system comprises a steam reformer, a water gas shift stage, a pressure swing adsorption unit and a dual fuel burner. Sensitivity analysis with Aspen Plus shows a positive effect on overall system efficiency for high pressure and low steam-to-carbon ratio. A theoretical maximum efficiency (based on lower heating value) of 78.2% can be obtained requiring a complex and costly heat exchanger network. Consequently, a system simplification is proposed resulting in a novel fuel processor concept for steam reforming of biodiesel based on a fully heat integrated system. A thermal System efficiency of 75.6% is obtained at S/C ¼ 2.53, p ¼ 13 bara and T ¼ 825 �C. The technoeconomic evaluation reveals hydrogen production costs ranging from 5.77 V/kg to 11.15 V/kg (depending on the biodiesel market price).