(559e) Kinetics and Techno-Economic Analysis of the Boudouard Reaction System Applied to Long Distance Thermal Energy Transport

The delivery of high-quality process heat derived from clean sources with high exergetic efficiency to distant locations (e.g., tens of kilometers) would be an enabling technology to decarbonizing the industrial sector. Our lab has been exploring the use of the Boudouard family of reactions including the simple Boudouard reaction [1,2]:

2CO ↔ CO₂ + C ΔH = -171 kJ

And the Sorption Assisted Boudouard Reaction [3]:

2CO + MO ↔ MCO₃ + C ΔH = -350 kJ ~ -440 kJ

where M represents a Group 2A element.

This is practical because a) the large positive entropy term causes the reaction to favour the left hand side of the equations at high temperature, yielding a strongly endothermic reaction that enables heat capture; b) in the presence of an adequate catalyst at suitable temperatures, and partial pressures of the reactant and product gases the reaction will favour the right hand term; and c) since the CO is kinetically stable at ambient temperatures, thermal energy can be stored indefinitely, transported, and released again. The modeled roundtrip exergetic efficiency of the process may be as high as 80% at the ideal heat release temperature, or achieve slightly lower efficiency at temperatures over 1000°C.

In order to enable design of the heat capture and heat regeneration reactors, the reaction kinetics of the forward and reverse reactions must be known. In this presentation, these kinetics will be presented, and an initial technoeconomic model describing the integration of the technology into existing industrial applications will be shared.

References:

[1] Boudouard, O. Influence De La Vapeur D’eau Sur La Réduction De L’anhydride Carbonique Par Le Charbon C. R. Hebd. Acad. Sci. 1905, 141, 252– 253.

[2] See, for example, a) Yokochi, A. et al. Thermal Energy Storage Using Sorption-Assisted Boudouard Processes 2021 AIChE Annual, Nov 7-19 2021; b) 737e. Alexandre Yokochi, Riley Choquette, Benjamin Phillips and Annette von Jouanne, School of Engineering and Computer Science, Baylor University, Waco, TX 2022 AIChE Annual, Nov 11-22 2022; 264c Thermal Energy Transport Using the Sorption-Assisted Boudouard Reaction; c) Alexandre Yokochi, Riley Choquette, Benjamin Phillips and Annette von Jouanne, School of Engineering and Computer Science, Baylor University, Waco, TX 2023 AIChE Annual, Nov 4-10 2023;

[3] Rout, K.R. et al. Highly Selective CO Removal by Sorption Enhanced Boudouard Reaction for Hydrogen Production Catal. Sci. Technol. 2019, 9, 4100–4107.