(168b) Towards Hydrogen Production By Produced Water Utilization: Understanding the Impact of Water Impurities on Methane Reforming

At present most of the US’s commercially used hydrogen, up to 95%, is produced from steam methane reforming (SMR) and SMR is likely to remain a key component of the hydrogen economy in the foreseeable future. However, the clean water consumption of SMR is a major concern and replacing clean water with impure water streams is an excellent opportunity to recover wasted heat from water treatment and decrease the cost of hydrogen production. Reviewing recent literature, we find several teams are integrating SMR with impure wastewater streams but we find several significant gaps. Produced and flowback waters from oilfields are currently underutilized, with most being reinjected into the oil reservoir for enhanced oil recovery or injected into storage wells to prevent contamination of surface water. Only small amount is treated for release above the water table, and there are no reports of its use in SMR to produce hydrogen for use in refining or for sale. We propose combining supercritical water desalination/oxidation (SCWDO) and SMR processes to exploit this gap, simultaneously producing usable water and cheap hydrogen for energy storage. To support this integration, we present findings of the initial composition of water produced from Wyoming natural gas fields and examine the impacts of treated water of varying quality on commercial nickel SMR catalyst. Using SCWDO water that is treated to clean water act compliant levels of dissolved solids has only a small impact on catalyst life compared to deionized water, suggesting that this may merit further development.