A Novel Technology for Low-Carbon Hydrogen from H₂S: A Large-Scale Techno-Economic and Environmental Assessment

H₂S, a waste gas in oil & gas industry is usually incinerated in the Claus process.H₂S-methane reforming (H₂SMR) is a new technology developed at KU-RICH for producing low-cost and low-carbon hydrogen, key for the hydrogen economy.This work provides a comparative techno-economic and environmental assessment for alternative hydrogen-production via H₂S methane reforming where H₂S substitutes water in the conventional Steam methane reforming process (SMR).A large-scale H₂SMR process is developed and benchmarked against SMR with CO₂ capture (SMR+CC) in addition to methane thermal decomposition (CH₄Pyrol).The study reveals the comparable energy intensity of H₂SMR and SMR+CC at 148-149 MJ.kgH₂^-1 while CH₄Pyrol has the least energy intensity of 75 MJ.kgH₂^-1.The added-value of process byproducts of H₂SMR and CH₄Pyrol improved their levelized cost of hydrogen (LCOH) to $-1.00 and $1.93 per Kg, respectively compared to SMR+CC with $4.13 per kg and $2.41 per kg excluding and including CO₂ selling credits.The carbon footprint of the three pathways is demonstrated via a gate-to-gate lifecycle assessment obtained in the order of H₂SMR < CH₄Pyrol< SMR+CC.