(678b) Development of the Ohio State Natural-Gas Conversion Technology Using Iron-Based Chemical Looping Process for Hydrogen and Electricity Production

The global energy consumption is projected to rise by 36% in the year 2035, with fossil fuels like natural gas expected to supply for around 53% of the increase. The importance of natural gas utilization for production of electricity and chemical intermediates such as hydrogen and syngas is highlighted by the current utilization estimates, i.e.,23 trillion cubic feet, and the projected increase in consumption by 44% in 2035. The recent technological developments in natural gas utilization focus on minimizing the cost increment incurred by reduction in carbon emissions. The chemical looping technology in general is projected as a promising candidate to give the maximum cost-benefit in a carbon constrained scenario for natural gas utilization. 

The syngas chemical looping technology developed at The Ohio State University employs the iron-based oxygen carrier and the gas-solid countercurrent moving-bed reactoras a reducer. This technology has been demonstrated at 25 kW_th sub-pilot scales using various feedstocks for near 1000 hours. This presentation analyzes the natural gas conversion effect using this technology. Specifically, the study examines the thermodynamic limits for full conversion of natural gas and the reduction kinetics under high pressure conditions for oxygen carrier reactions with methane. The results of this study are used to delineate the overall cold-gas and thermal efficiency for H₂ and electricity generation for the syngas chemical looping process system. The comprehensive techno-economic analysis based on the process efficiency and their critical comparisons with the existing technologies such as natural gas combined cycle and steam-methane reforming are also made.