Search

Simulation Study of Natural Gas Blending with Hydrogen and Dissociated Methanol Gas for Boiler Combustion

Author(s)

Weihong Xu1, Ruhuan Jiang1, Lunhong Chen2, Yankun Jiang1,3,*

Affiliation(s)

1School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China 2Hubei Huayang Automobile Transmission System Co., Ltd, Shiyan, Hubei, China 3State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei, China *Corresponding Author.

Abstract

In light of the worldwide consensus on net-zero emissions, using clean fuels to wholly or substantially replace traditional fuels has emerged as the dominant route of industrial development. This paper presents a methanol-hydrogen co-combustion method for boilers, based on methanol, a zero-carbon fuel produced from CO₂. The technique uses boiler waste heat to catalytically fracture methanol into dissociated methanol gas (DMG), largely composed of H₂ and CO. The DMG is blended with the original fuel to improve thermal efficiency and minimize emissions. A three-dimensional geometric model was developed with a tiny direct-current natural gas (NG) boiler as the research subject. The combustion characteristics of natural gas mixed with various concentrations of DMG and hydrogen were simulated using the finite volume approach. Blending hydrogen and DMG at a flow rate of 10 m³/h and a surplus air ratio of 1.2 improves the NG heat release rate and furnace temperature. At a 5% hydrogen mixing ratio, the heat release rate rises by up to 2.2%, while the average furnace temperature reaches a high of 1886 K. Meanwhile, at a DMG mixing ratio of 10%, the heat release rate increases by a maximum of 2.1%, while at a mixing ratio of 5%, the average furnace temperature reaches 1895 K. Overall, hydrogen has a greater effect on increasing the heat release rate of NG combustion, whereas DMG has a larger potential to raise furnace temperature.

Keywords

Boiler; Natural Gas; Hydrogen; Dissociated Methanol Gas; Combustion Simulation

References

[1] Liu J, Zhuang Y, Wang C, et al. Life cycle carbon footprint assessment of coal-to-SNG/methanol polygeneration process. Science of The Total Environment, 2024, 908: 168409. [2] Wang X, Demirel Y a. Feasibility of power and methanol production by an entrained-flow coal gasification system. Energy & Fuels, 2018, 32(7): 7595-7610. [3] Tian Z, Wang Y, Zhen X, et al. The effect of methanol production and application in internal combustion engines on emissions in the context of carbon neutrality: A review. Fuel, 2022, 320: 123902. [4] Impacts of methanol fuel on vehicular emissions: A review. Frontiers of Environmental Science & Engineering, 2022, 16(9). [5] Gu Y, Wang D, Chen Q, et al. Techno-economic analysis of green methanol plant with optimal design of renewable hydrogen production: A case study in China. International Journal of Hydrogen Energy, 2022, 47(8): 5085-5100. [6] Crivellari A, Cozzani V, Dincer I. Exergetic and exergoeconomic analyses of novel methanol synthesis processes driven by offshore renewable energies. Energy, 2019, 187. [7] X. Z. Liu, G. Y. Zhu, T. Asim, R. Mishra. Combustion characterization of hybrid methane-hydrogen gas in domestic swirl stoves. Fuel, 2023, 333: 126413 [8] D. T. Balanescu, V. M. Homutescu. Effects of hydrogen-enriched methane combustion on latent heat recovery potential and environmental impact of condensing boilers. Applied Thermal Engineering, 2021, 197: 117411 [9] M. X. Sun, X. M. Huang, Y. L. Hu, S. Lyu. Effects on the performance of domestic gas appliances operated on natural gas mixed with hydrogen. Energy, 2022, 244: 122557 [10] Ali A, Shaikh M N. Recent developments in catalyst design for liquid organic hydrogen carriers: Bridging the gap to affordable hydrogen storage. International Journal of Hydrogen Energy, 2024, 78: 1-21. [11] Jiang Yankun. Alcohol-Hydrogen Automotive Technology and Its Power System. Proceedings of the 2017 International Clean Energy Forum. Macau, 2017: 257-275. [12] Jiang Y, Chen Y, Xie M. Effects of blending dissociated methanol gas with the fuel in gasoline engine. Energy, 2022, 247. [13] Guban D, Muritala I K, Roeb M, et al. Assessment of sustainable high temperature hydrogen production technologies. International Journal of Hydrogen Energy, 2020, 45(49): 26156-26165. [14] Chen Y, Jiang Y, Zhang B, et al. Impact of preparation methods on the performance of Cu/Ni/Zr catalysts for methanol decomposition. Materials Research Express, 2024, 11(2). [15] Liu Bin. Fluent 19.0 Fluid Simulation: From Beginner to Master. Beijing: Tsinghua University Press, 2019.