Screening of different manganese ores for chemical-looping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU)

Paper in proceeding, 2014

Oxygen carriers based on manganese oxides have recently shown great promise for use in chemicallooping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU). In this work, different manganese ores have been investigated for application in CLC and CLOU. The reactivity towards methane and synthesis gas (50% CO in H2) and the oxygen uncoupling behaviour at 900, 950 and 1000°C have been investigated. The mechanical stability and integrity of the ores were also evaluated in a jet-cup attrition rig. It was found that some of the ores could convert approximately 70-80% of methane added to carbon dioxide, and most of them achieved almost complete gas yield for synthesis gas. The materials released small amounts of oxygen during the inert cycles. Some of the investigated ores also exhibited low rates of attrition. The combination of high reactivity with different fuel gases, relatively low attrition rates and low cost make these manganese ores highly interesting for a CLC process based on interconnected fluidized beds.