Towards sustainable hydrogen production: Integrating electrified and convective steam reformer with carbon capture and storage
Diego Maporti, Simone Guffanti, Federico Galli, Paolo Mocellin, Gianluca Pauletto
Abstract
• SMR electrification (e-SMR) saves 28 % NG and cuts CO 2 production by 34 %. • PSA tail gas integration with convective SMR permits feedstock conversion by 31%. • Blue H 2 based on e-SMR with CCS cuts CO 2 emissions by 82% compared to fired SMR. • H 2 by e-SMR with CCS is cheaper than fired SMR with CCS (28.3 vs 30.8c€ Nm −3 H 2 ). This work reports the design of a process for hydrogen production based on electrified steam methane reforming (e-SMR) coupled with a convective reforming (convective SMR) and carbon capture and storage (CCS) as an alternative to conventional fuel-fired reforming to reduce natural gas (NG) consumption as well as carbon dioxide emissions. The energy required by the reforming reaction is supplied by direct electric heating instead of burning fossil fuel in the radiant section of a furnace, saving 35 % NG and reducing CO 2 emission by 29 %. Implementing convective SMR reduces the electric load of the main e-SMR reactor and ensures a slightly higher thermal efficiency (80.2 %) compared to conventional fuel-fired reforming (78.9 %). Further CO 2 emissions (85 %) and NG consumption reduction (50 %) are possible by adopting amine-based CO 2 capture. If coupled with an energy integration scheme, it is possible to capture 75 % of the CO 2 produced, preserving high energy efficiency (79.4 %). This requires only a 14 % increase in capital costs, which is strongly beneficial compared to applying CO 2 capture to flue gases of the fuel-fired reforming (69.8 % efficiency and 80 % more capital costs). The process based on e-SMR coupled with convective SMR and CO 2 capture ensures a levelized cost of hydrogen (LCOH) of 0.281 € Nm −3 H 2 , which is much lower than the conventional fuel-fired reforming with CO 2 capture applied to flue gases (0.309 € Nm −3 H 2 ). Moreover, it has comparable CO 2 emissions (1.59 vs 0.99 kg CO 2 emitted kg −1 H 2 ) but produces lower CO 2 (6.39 vs 9.88 CO 2 produced kg −1 H 2 ) compared to fuel-fired reforming due to using renewable electricity as energy source for the SMR. Compared to conventional fuel-fired reforming, the same process provides similar LCOH (0.283 vs 0.282 € Nm −3 H 2 ) but with drastically lower CO 2 emissions (1.59 vs 8.99 kg CO 2 emitted kg −1 H 2 ).