Hydrothermal Liquefaction of Agricultural Residues for Renewable Bio-Crude Production: Energy Yield and Emission Reduction Potential
DOI:
https://doi.org/10.17524/ijesmi.v1i2.14Keywords:
Hydrothermal Liquefaction, Agricultural Residues, Bio-Crude Oil, Life Cycle Assessment, Greenhouse Gas Mitigation, Renewable energy, Waste ValorizationAbstract
The escalating global energy demand, coupled with the imperative to reduce greenhouse gas emissions, necessitates the development of sustainable alternatives to fossil fuels. This study investigates the Hydrothermal Liquefaction (HTL) of abundant agricultural residues—sugarcane bagasse, wheat straw, and rice husk—for the production of renewable bio-crude oil. Experiments were conducted in a batch reactor at temperatures ranging from 280–320°C to optimize the yield and quality of bio-crude. The results showed that a reaction temperature of 300°C yielded maximum bio-crude outputs of 38.2 wt%, 42.5 wt%, and 35.1 wt% (dry ash-free basis) for bagasse, wheat straw, and rice husk, respectively, with corresponding energy recoveries of up to 78.5%. The bio-crude exhibited improved fuel properties, with higher heating values between 30–34 MJ/kg. A comprehensive life cycle assessment (LCA) revealed that the integrated HTL system, when accounting for avoided fossil fuel use and prevention of open-field burning, achieves net-negative greenhouse gas emissions, ranging from -32.1 to -47.4 g CO₂-eq per MJ of bio-crude. The findings confirm that HTL of agricultural waste is a technically feasible and environmentally strategic pathway for producing low-carbon liquid biofuels, directly contributing to waste valorization, energy security, and climate change mitigation by phasing out fossil-derived fuels.
Downloads
References
[1] IEA, World Energy Outlook 2023, Paris: International Energy Agency, 2023.
[2] A. H. Al-Muhtaseb et al., “Circular bioeconomy and integrated biorefinery for sustainable bioenergy,” Renew. Sustain. Energy Rev., vol. 189, p. 113989, 2024.
[3] G. K. Parshetti, A. A. L. Ahmad, and S. E. I. Elkanzi, “Hydrothermal liquefaction of lignocellulosic biomass: mechanisms, challenges, and prospects,” Bioresour. Technol., vol. 310, p. 123444, 2020.
[4] T. J. Strathmann, J. R. V. Flora, and C. M. Rocheleau, “Hydrothermal liquefaction of biomass: A critical review of process chemistry and engineering,” Energy Environ. Sci., vol. 14, no. 12, pp. 6127–6176, 2021.
[5] L. García Alba, C. Torri, and D. Fabbri, “Hydrothermal treatment of microalgae: product pathways and process optimization,” Algal Res., vol. 56, p. 102317, 2021.
[6] C. Xu, Z. Wang, and J. Sun, “Bio-crude oil production from hydrothermal liquefaction of wastewater algae: product characteristics and energy recovery,” Fuel, vol. 279, p. 118523, 2020.
[7] Y. Chen, Y. Wu, and P. Zhang, “Hydrothermal liquefaction of sewage sludge: product distribution and nutrient recovery potential,” Water Res., vol. 178, p. 115832, 2020.
[8] S. S. Toor, L. Rosendahl, and A. Rudolf, “Hydrothermal liquefaction of lignocellulosic biomass: a review of subcritical water technologies,” Energy, vol. 36, no. 5, pp. 2328–2342, 2011.
[9] M. A. Sunny, H. K. Jeswani, and A. Azapagic, “Techno-economic analysis of hydrothermal liquefaction for bio-crude production: a comparative assessment,” Appl. Energy, vol. 283, p. 116276, 2021.
[10] H. K. Jeswani, R. W. Smith, and A. Azapagic, “Life cycle assessment of biofuel production via hydrothermal liquefaction: environmental impacts and improvement potentials,” J. Clean. Prod., vol. 289, p. 125754, 2021.
[11] P. Biller, A. B. Ross, and M. M. Y. Leung, “Environmental assessment of biofuel from hydrothermal liquefaction: a well-to-wheel perspective,” GCB Bioenergy, vol. 13, no. 4, pp. 616–632, 2021.
[12] R. B. Gupta, S. Demirbas, and M. T. Klein, “HTL of model biomass compounds: reaction pathways and product distributions,” Ind. Eng. Chem. Res., vol. 59, no. 39, pp. 16923–16934, 2020.
[13] J. Watson, Y. Zhang, and T. H. Pedersen, “Product distribution from HTL of glucose and cellulose: insights into reaction mechanisms,” Fuel Process. Technol., vol. 209, p. 106557, 2020.
[14] A. A. Peterson, D. C. Elliott, and J. M. Billing, “Challenges and opportunities in hydrothermal liquefaction of high-ash agricultural residues,” ACS Sustain. Chem. Eng., vol. 10, no. 1, pp. 113–124, 2022.
[15] D. López Barreiro, C. Rueda, and W. Prins, “Influence of ash content and composition on hydrothermal liquefaction of biomass: yield and quality implications,” Biomass Bioenergy, vol. 158, p. 106354, 2022.
[16] F. Yang, L. Wang, and S. Li, “Integrated yield and life cycle assessment of straw hydrothermal liquefaction for sustainable biofuel production,” Energy Convers. Manag., vol. 267, p. 115937, 2022.
[17] S. S. Azizi, M. A. Al-Muhtaseb, and M. N. Mohammed, “A comprehensive review on hydrothermal liquefaction of agricultural waste: feedstock, process, and products,” Renew. Sustain. Energy Rev., vol. 173, p. 113102, 2023.
[18] M. M. Wright, J. A. Satrio, and R. C. Brown, “Prospects for biofuels from hydrothermal liquefaction: techno-economic and policy perspectives,” Biofuels, Bioprod. Bioref., vol. 17, no. 3, pp. 615–632, 2023.
[19] J. A. Okolie, S. Nanda, and A. K. Dalai, “Sustainable energy production from agro-residues via hydrothermal liquefaction: process optimization and product upgrading,” Chem. Eng. J., vol. 455, p. 140700, 2023.
[20] R. Luque, J. C. Serrano-Ruiz, and A. Pineda, “Waste-to-energy via hydrothermal processes: advancements and future directions,” Prog. Energy Combust. Sci., vol. 93, p. 101037, 2022.
