(596f) Membrane-Based Hydrogen Separation from Syngas Towards Refinery Decarbonization

Hydrogen (H₂) production is a steppingstone towards combating climate change by transitioning to more sustainable energy sources. Currently, H₂ is dominantly produced through steam methane reforming (SMR) process, which is considered to be an intense CO₂ emitting process. According to the International Energy Association (IEA), as of 2023, the average estimated CO₂ emissions intensity associated with H₂ production through SMR is around 10-14 kg CO₂-eq/kg H₂. Development in carbon capture and storage technologies can reduce the CO₂ emissions intensity down to 5-8 kg CO₂-eq/kg H₂ (with a CO₂ capture rate of around 60%), and to 0.8-6 kg CO₂-eq/kg H₂ (with a capture rate above 90%). Carbon Capture and Utilization (CCU) are used to produce low-carbon H₂. However, such process modifications are expensive to develop and operate, creating an obstacle in the deployment of low-carbon hydrogen from hydrocarbons.

Moreover, the final step of hydrogen purification through Pressure Swing Adsorption (PSA) or cryogenic distillation post the SMR unit contributes significantly to the overall cost of H₂ produced. Comparatively, the operation of palladium-based membranes requires lower cost and energy, in addition, its high permeability and selectivity for H₂ makes it exemplary for hydrogen purification.

This study investigates the use of palladium-based membranes for H₂ separation after different process steps with multiple heat recovery options to analyze the overall system performance under varying operation conditions. Aspen Plus V.12 is utilized to model the proposed configurations whereas the membrane-based H₂ separation model is developed in conjunction with lab-scale experimental results. The comparative performance of each modelled configuration and the progress of the palladium-based membrane technology at Saudi Aramco’s Research and Development Center will be presented.