Potential cost savings of large-scale blue hydrogen production via sorption-enhanced steam reforming process

As countries work towards achieving net-zero emissions, the need for cleaner fuels has become increasingly urgent. Hydrogen produced from fossil fuels with carbon capture and storage (blue hydrogen) has the potential to play a significant role in the transition to a low-carbon economy. This study examined the technical and economic potential of blue hydrogen produced at 600 MWth(LHV) and scaled up to 1000 MWth(LHV) by benchmarking sorption-enhanced steam reforming process against steam methane reforming (SMR), autothermal gas-heated reforming (ATR-GHR) integrated with carbon capture and storage (CCS), and SMR with CCS. Aspen Plus® was used to develop the process model, which was validated using literature data. Cost sensitivity analyses were also performed on two key indicators: levelised cost of hydrogen and CO2 avoidance cost by varying natural gas price, electricity price, CO2 transport and storage cost, and carbon price. Results indicate that, at a carbon price of 83 £/tCO2e, the LCOH for SE-SR of methane is the lowest at 2.85 £/kgH2, which is 12.58% and 22.55% lower than that of ATR-GHR with CCS and SMR plant with CCS, respectively. The LCOH of ATR-GHR with CCS and SMR plant with CCS was estimated to be 3.26 and 3.68 £/kgH2, respectively. The CO2 avoidance cost was also observed to be lowest for SE-SR, followed by ATR-GHR with CCS, then SMR plant with CCS, and was observed to reduce as the plant scaled to 1000 MWth(LHV) for these technologies

Modelling of sorption-enhanced steam reforming (SE-SR) process in fluidised bed reactors for low-carbon hydrogen production: A review

Sorption-enhanced steam reforming (SE-SR) offers lower capital costs than conventional steam reforming with carbon capture, which arises from the compact makeup that allows reforming and CO2 capture to occur in a single reactor. However, the technology readiness level (TRL) of SE-SR technology is currently low and large-scale deployment can be expedited by ramping up activities in reactor modelling and validation at pilot scale. This work first explores the concept of SE-SR technology, then the experimental activities and pilot tests performed for this technology, followed by the review of progress made on SE-SR modelling. It was found that the Eulerian-Eulerian two-fluid model is the most popular approach widely adopted for modelling SE-SR in fluidised bed reactors. However, the averaging method used to close equations ignores flow details at particle level and simplifies the particle system. Moreover, while hydrogen purity and yield have been predicted within an acceptable error, larger errors for CO2 gas output relative to experimental data have been reported for this model type. Limitations and future perspectives for reactor designs and the various models and modelling approaches are also analysed, to provide guidance and advance research, modelling and scaleup of SE-SR technology

Review of Cryogenic Carbon Capture Innovations and Their Potential Applications

Our ever-increasing interest in economic growth is leading the way to the decline of natural resources, the detriment of air quality, and is fostering climate change. One potential solution to reduce carbon dioxide emissions from industrial emitters is the exploitation of carbon capture and storage (CCS). Among the various CO2 separation technologies, cryogenic carbon capture (CCC) could emerge by offering high CO2 recovery rates and purity levels. This review covers the different CCC methods that are being developed, their benefits, and the current challenges deterring their commercialisation. It also offers an appraisal for selected feasible small- and large-scale CCC applications, including blue hydrogen production and direct air capture. This work considers their technological readiness for CCC deployment and acknowledges competing technologies and ends by providing some insights into future directions related to the R&D for CCC systems

Computational simulation of SE-SR of methane in a bench-scale circulating fluidised bed reactor: Insights into the effects of bed geometry design and catalyst-sorbent ratios

Operating sorbent-enhanced steam reforming (SE-SR) of methane in fluidised bed reactors presents a promising pathway for industrial low-carbon hydrogen production. However, further understanding of its complex multi-phase behaviours under certain operating conditions is still needed to guide reactor design and scale-up. This study developed a computational particle fluid dynamic (CPFD) reactor model to study cyclic SE-SR performance. The model was used to simulate scenarios representing potential reductions in catalyst activity and sorbent inventory levels over time by varying catalyst-sorbent ratios. Additionally, the effects of two different bed geometry designs were examined. Results indicate that varying solids ratios influenced reaction progress, with optimised methane conversion and CO2 capture observed at moderate ratios. Higher sorbent loadings enhanced thermal neutrality but risked increased calciner energy penalties. Bed geometry also influenced localised hydrodynamics. Detailed solids and gas concentration contours provided insight into segregation and spatial product distribution in the two designs

Steam reforming process for conversion of hydrocarbons to hydrogen

For many years, the steam reforming process has been used to generate hydrogen gas from a variety of feedstocks, including natural gas, propane, naphtha, and coal. The hydrocarbons are converted into hydrogen gas and carbon dioxide using a catalyst and high-temperature steam. This chapter provides an in-depth overview of the steam reforming process and its fundamental principles, including its chemistry and thermodynamics. It also looks at the different catalysts used in the process, as well as the role of temperature, pressure, and steam-to-carbon ratio in the reforming of lighter and heavier hydrocarbons. Finally, the design and operation of steam reforming reactors were explored, highlighting the ongoing research and development efforts to improve the process efficiency