Performance of a low-cost iron ore as an oxygen carrier for Chemical Looping Combustion of gaseous fuels

• Published in: Chemical engineering research & design 2015-01, Vol.93, p.736-746
• Main Authors: Pans, Miguel A., Gayán, Pilar, de Diego, Luis F., García-Labiano, Francisco, Abad, Alberto, Adánez, Juan
• Format: Article
• Language: English
• Subjects: Carriers; Catalysis; Catalysts; Chemical Looping Combustion; CO2 capture; Combustion; Fuels; Gaseous fuels; Iron; Iron and steel plants; Iron ore; Ni addition; Nickel; Oxygen carrier; Syngas
• ISSN: 0263-8762; 1744-3563
• DOI: 10.1016/j.cherd.2014.07.001

•The performance of an iron ore as OC for CLC with gaseous fuels is evaluated.•The ore can fully convert syngas at 880°C in a 500W continuous unit.•A very low conversion of methane containing fuels was observed.•The addition of a Ni-based OC to improve conversion was tested.•The absence of a catalytic effect was deeply analyzed. This work evaluates the performance of an iron ore, mainly composed of Fe2O3, as an oxygen carrier (OC) for Chemical Looping Combustion (CLC) with gaseous fuels. The OC was characterized by TGA and evaluated in a continuous 500Wth CLC unit, using CH4, syngas and a PSA off-gas as fuels. The OC was able to fully convert syngas at 880°C. However, lower conversion rates were observed with methane-containing fuels. The addition of a Ni-based OC was evaluated in order to increase the reactivity of the OC with methane. In spite of this, an absence of catalytic effect was observed for the Ni-based OC. A deep analysis was carried out into the reasons for the absence of catalytic effect of the Ni-based OC. The performance of the iron ore with regard to attrition and fluidization behaviour was satisfactory throughout 50h of hot operation in the continuous CLC plant. Thus, this low cost material is a suitable OC for gaseous fuels mainly composed of H2 and CO.