Synthesis and upscaling of perovskite Mn-based oxygen carrier by industrial spray drying route

Artikel i vetenskaplig tidskrift, 2018

Chemical looping combustion (CLC) has inherent separation of the greenhouse gas CO 2 by avoiding direct contact between air and fuel. The transfer of oxygen is realised by metal oxide particles that continuously circulate between the air and fuel reactors. Promising particles are perovskite Mn-based oxygen carrier materials, which have proven their performance at lab-scale. To test these particles at an industrial scale, it is necessary to use more raw materials that are widely and cheaply available in bulk quantities. The development of these Mn-based oxygen carriers by the spray drying method was investigated in this study. Furthermore, the production method is transferred to industrial scale so that several tonnes of oxygen carriers could be produced. The characterization and the performance of these particles at lab and industrial scale is discussed. Different Mn ores and oxides were selected to study the effect of the used Mn source on the oxygen carrier performance. Particles suitable for chemical looping were made based on diverse Mn sources with different Mn oxidation states. The performance of the oxygen carrier was found to be heavily impacted by impurities in the raw materials. The best performing Mn oxide was selected for up-scaling and each step of the spray drying process was optimized at large scale. The thermal treatment of the particles at tonne scale remains a challenge, but particles with a good mechanical strength, sphericity and sufficient reactivity for methane were manufactured.