Metal Fuel Combustion Tests Using NRCan’s 0.3 MWth Vertical Combustor Research Facility

Abstract Reactive metals, such as iron (Fe) and aluminum (Al), have high energy density, making them a potentially suitable candidate for partial replacement of hydrocarbon fuels. These materials, herein referred to as metal fuels (MeFs), have the potential to simultaneously produce heat and power, zero-carbon hydrogen (H2), and other value-added products. To this end, the role of MeFs for producing clean hydrogen is becoming increasingly important for achieving 2050 net-zero emission targets and industrial decarbonization. To date, limited work has been done to demonstrate MeF combustion at pilot scale. In this paper, the preliminary results of MeF combustion using the 0.3 MWth Vertical Combustor Research Facility (VCRF) of Natural Resources Canada (NRCan) are presented. This facility was originally designed for advanced research on combustion of fossil fuels, including air- and oxy-combustion of solid, liquid, and gaseous fuels with CO2 capture, but has been recently retrofitted to be utilized for combustion of MeFs. The VCRF is equipped with a full range of instruments to monitor and record combustion process parameters in real time. These include combustion air flow, combustor pressure and temperature profile, as well as the flame shape and size (with the aid of a camera probe). This paper presents the results of co-firing of natural gas with two Fe powders (90 μm and 40 μm). The feedstock MeF powders were analyzed through particle size distribution (PSD) and scanning electron microscopy (SEM), to study the size, shape, and morphology of the particles. The preliminary tests with low MeFs firing rate showed promising results and further testing is ongoing with increased firing rate up to 0.3 MWth. The gaseous combustion products were measured by continuous emission monitoring (CEMs) analyzers during the tests, and solid particles were collected and characterized using SEM, energy dispersive spectroscopy (EDS), and x-ray diffraction (XRD).