Alloy Corrosion Considerations in Low-Cost, Clean Biomass Cookstoves for the Developing World

Nearly 40% of the world cooks on open fires or inefficient biomass-fueled cookstoves. The resulting smoke is a health hazard, contributing to an estimated 4 million premature deaths per year, as well as a major source of black carbon emissions. One solution is the introduction of improved, clean-burning biomass cookstoves. One of the most challenging components is the combustor, which must operate at high temperatures (often ≥ 600 °C) in the presence of highly corrosive species released from biomass fuel combustion, yet be sufficiently low cost to permit widespread adoption. The present work reports the development of accelerated corrosion test screening protocols employing highly corrosive salt and water vapor species, specifically designed to evaluate alloys for clean biomass cookstove combustors, and corrosion findings for a range of commercial and developmental alloys. A new Fe-Cr-Si base alloy that offers promise for improved corrosion resistance at lower cost than state-of the art FeCrAl and stainless steel alloys is also reported.