Ignition Characteristics of Recycled Iron Particles in Hot Coflow: Advancing the Recyclable Iron Fuel Cycle

This study investigates the ignition behavior of recycled iron particles under varying coflow temperature conditions to evaluate their reactivity and suitability for regeneration experiments. Experiments were conducted at coflow temperatures of 750°C, 800°C, and 850°C, with ignition percentages consistently exceeding 85% across all conditions. The minimal variability observed, as indicated by small error bars, highlights the stability and reproducibility of the ignition process. Experiments confirm that the ignition mechanism is largely independent of minor coflow temperature fluctuations within the studied range. Variations in ignition behavior were attributed to potential experimental factors, such as local turbulence, temperature gradients, or minor inconsistencies in particle properties, though their impact was found to be negligible. Moreover, in continuous burning test using a semi practical burner, recycled iron powder exhibited performance comparable to virgin iron powder, producing a stable flame, consistent high gas temperatures, and equivalent NO emissions. The results underscore the robustness and reliability of recycled iron particles in high-temperature reactive systems, demonstrating their potential as a promising material for regeneration and energy applications.