Veksha, A., Aryal, R., Low, C. W., Mohamed, D. K. B., Ha, Q. L. M., Chan, W. P., Lim, T.-T., & Lisak, G. (2025). Effect of feedstock on the operation of a combined pyrolysis-reforming prototype using a fluidized Ni/Al2O3 catalyst. Chemical Engineering Journal, 526, 171033. https://doi.org/10.1016/j.cej.2025.171033
Abstract:
Syngas- and H2-based fuels from solid waste feedstocks are essential for decarbonizing chemical production and reducing dependence on fossil resources. A combined pyrolysis-reforming prototype (300 g/h waste feedstock input) with a fluidized Ni/Al2O3 catalyst was designed to elucidate feedstock effects on reforming efficiency, catalyst stability, and system reliability. Pine sawdust (pine), dried municipal sewage sludge (sewage sludge), and refuse-derived fuel (RDF) were used to generate producer gas. Pine enabled stable pyrolysis–reforming for 6 h, yielding 45–52 vol% H2 and 33–34 vol% CO, with minimal tar (0–2 g/Nm3) and the lowest C1–C5 hydrocarbon concentrations in the producer gas. Sewage sludge also sustained 6 h of operation but produced lower H2 (39–45 vol%) and CO (19–20 vol%), higher tar (25–35 g/Nm3) and C1–C5 concentrations, as the catalyst activity was suppressed by Ni sulfidation and, probably, coking. RDF trials were stopped after 2 h due to severe coking at the reformer inlet and tar condensation on equipment walls (not the catalyst bed), the lowest H2 (34–37 vol%) and CO (14–17 vol%) concentrations and insufficient tar (~47 g/Nm3) and C1–C5 (26–31 vol%) reforming. Regardless of the feedstock, class 4 polyaromatic tar compounds were consistently the most abundant tar species. C1–C5 hydrocarbon concentrations exhibited a strong empirical correlation with quantified tar concentration (adjusted R2 = 0.951), enabling real-time process monitoring and control. Catalyst testing showed no statistically significant effect of feedstock on differences in catalyst porosity or Ni loss due to attrition. Based on these findings, a feedstock-specific technology development roadmap was proposed, focusing on the research of unaddressed issues in the development of robust, scalable pyrolysis–reforming systems tailored to diverse waste streams.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research (A*STAR) - Industry Alignment Fund – Industry Collaboration Project [Project Reference No.: I2101E0006]
Grant Reference no. : NA
This research / project is supported by the National Environment Agency - Waste-to-Energy Test-Bedding and Demonstration Initiative
Grant Reference no. : WTETD-2019-1R-04
This research / project is supported by the PUB, Singapore’s National Water Agency - RIE2025 Urban Solutions and Sustainability (USS) (Water) Center of Excellence (CoE) Program awarded to the Nanyang Environment & Water Research Institute (NEWRI), Nanyang Technological University
Grant Reference no. :