(232f) Techno-Economic and Life Cycle Analysis of Conversion of Natural Gas and Biomass to Hydrogen and Performance Carbons

The transition towards a sustainable energy future necessitates the development of technologies that can efficiently produce clean energy carriers and valuable by-products from renewable and abundant resources. Hydrogen presents a versatile alternative for heat and power generation in applications traditionally reliant on fossil hydrocarbons. Currently, steam methane reforming (SMR) dominates global hydrogen production, yielding 13.7 CO₂ (equiv.)/kg of net hydrogen, contributing to substantial greenhouse gas emissions [1]. SMR's dependence on finite, cost-effective natural gas and associated CO₂ release risks necessitate exploring alternatives. Methane pyrolysis emerges as a promising option, producing molecular hydrogen and solid carbon without CO₂ byproducts. Different catalysts such as nickel, molybdenum, and carbon have been investigated for pyrolysis at temperatures of 500-900°C. Still, the removal of carbon fibers from catalysts is challenging and, despite innovations in pyrolysis reactor designs, there has been little cost-effective management scheme identified [2]. While small-scale pyrolysis may yield additional revenue from carbon products, achieving significant global carbon emission reductions requires large-scale implementation with perpetual solid carbon storage. The cost of producing hydrogen can be reduced if the carbon produced from pyrolysis can be converted into high-performance carbon materials such as carbon nanotubes. These performance carbons possess unique properties, such as high strength, thermal and electrical conductivity, and adsorption capabilities, making them valuable for a wide range of applications such as in wastewater treatment and the fabrication of composite materials [3].

Another potential source of hydrogen production is biomass. Traditionally, biomass has been primarily viewed as a means to produce liquid biofuels, such as bioethanol and green diesel. However, the process of biomass gasification can produce a significant quantity of H₂, which then needs to be purified or separated from other gases produced during gasification [4]. Consequently, recent research has focused on assessing hydrogen production through co-feeding biomass with natural gas to identify technologies that show promise in terms of both yield and energy efficiency [5].

The objective of this study is to formulate a techno-economic analysis (TEA), comprising a process model, economic calculations, and sensitivity analysis, coupled with a Life Cycle Assessment (LCA) for the entire system. The design and research are based on research at Iowa State University and the University of Oklahoma. Utilizing a combination of data from experimental setups and commercial technology evaluations, we are developing a scalable process model using BioSTEAM that simulates the operational conditions optimal for maximizing hydrogen yield while ensuring the production of high-quality carbon nanomaterials. The design specifies a processing capacity of 2000 dry metric tons of corn stover and 1200 tonnes of natural gas per day and incorporates other sources for technologies that will ascertain the industrial-scale competitiveness of hydrogen against SMR. Subsequent analysis will assess the economic and environmental viability of incorporating catalytic pyrolysis into the system.

We conducted preliminary TEA using general models by Riley et al., 2021 [6] and Swanson et al., 2010 [7] for the pyrolysis of natural gas and gasification of biomass, respectively. We obtained a minimum fuel selling price of hydrogen at $1.63/kg through natural gas pyrolysis. The initial results suggest an immense potential for cost reduction, which motivates further research. Our findings aim to propel the dialogue on sustainable hydrogen production forward, emphasizing the dual benefits of energy carrier generation and value-added carbon material production as integral to achieving a carbon-neutral future.

Acknowledgements:

The authors gratefully acknowledge the funding for the project from the National Science Foundation (NSF) with the NSF Award number 2218070.

References:

• Abbas, H. F., Daud, W. W. (2010). ‘Hydrogen production by methane decomposition: a review’, International Journal of Hydrogen Energy, 35(3), 1160-1190.

• Parkinson, B. et al. (2017) ‘Techno‐economic analysis of methane pyrolysis in molten metals: Decarbonizing Natural Gas’, Chemical Engineering & Technology, 40(6), pp. 1022–1030. doi:10.1002/ceat.201600414.

• Sánchez-Bastardo, N., Schlögl, R. and Ruland, H. (2021) ‘Methane pyrolysis for zero-emission hydrogen production: A potential bridge technology from fossil fuels to a renewable and sustainable hydrogen economy’, Industrial & Engineering Chemistry Research, 60(32), pp. 11855–11881. doi:10.1021/acs.iecr.1c01679.

• Tanksale, A., Beltramini, J.N., Lu, G.M. (2010) ‘A review of catalytic hydrogen production processes from biomass’, Renewable and Sustainable Energy Reviews, Elsevier, vol. 14(1), pages 166-182.

• Lalsare, A., Wang, Y., Li, Q., Sivri, A., Vukmanovich, R.J., Dumitrescu, C.E., Hu, J. (2019) ‘Hydrogen-Rich Syngas Production through Synergistic Methane-Activated Catalytic Biomass Gasification’, ACS Sustainable Chemistry & Engineering, 7(19), 16060-16071.

• Riley, J., Atallah, C., Siriwardane, R., Stevens, R. (2021) ‘Technoeconomic analysis for hydrogen and carbon co-production via catalytic pyrolysis of methane’, International Journal of Hydrogen Energy.

• Swanson, R. M., Platon, A., Satrio, J. A., & Brown, R. C. (2010). Techno-economic analysis of biomass-to-liquids production based on gasification. Fuel, 89, S11-S19. https://doi.org/10.1016/j.fuel.2010.07.027