A thermodynamic comparison between conventional, autothermal, and sorption-enhanced bio-oil steam reforming

Using Aspen Plus V12.1 software, simulations were performed to evaluate the hydrogen production, energy requirements, and the influence of key process variables such as temperature, pressure, or steam-to-carbon ratio. While traditional steam reforming is capable of achieving high hydrogen production, it requires substantial external energy input to drive forward the reaction given the endothermic nature of the reactions.

In comparison, autothermal reforming allows thermal neutral conditions by integrating endothermic steam reforming with exothermic partial oxidation reactions. Although the energy requirements significantly decrease, it also leads to lower hydrogen yields due to its consumption in the oxidation processes. In contrast, sorption-enhanced steam reforming improves hydrogen production compared to the other configurations ascribed to the in-situ CO2 capture by using sorbents that shift the equilibrium towards hydrogen with purities over 98%, thus minimizing the need for additional gas separation processes apart from reducing the CO and CH4 formation.