Production and examination of oxygen carrier materials based on different manganese ores with addition of calcium hydroxide or iron oxide in chemical-looping combustion
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Typ
Examensarbete för masterexamen
Master Thesis
Master Thesis
Program
Publicerad
2013
Författare
Mohammad Pour, Nasim
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Chemical-looping combustion (CLC) is an emerging method to capture carbon dioxide during combustion. It utilizes an oxygen carrier, normally particles of metal oxide, that is circulating between two fluidized bed reactors. One of the main challenges of this method is the cost of oxygen carries, which is composed of the cost of raw materials and the manufacturing cost. This study involves production of oxygen carriers by using six different manganese ores. Two additive materials, calcium hydroxide and iron oxide, were added to improve the characteristics of the ores. The method utilized to manufacture particles is extrusion, in which materials used for oxygen carrier preparation are mixed mechanically and extruded. The extrudates are then dried and sintered at high temperatures. Methane and syngas conversion as well as oxygen release in inert atmosphere were investigated for the oxygen carriers produced. Wood char conversion for three of the samples with addition of calcium hydroxide sintered at 1300°C for 6 hours as well as petroleum coke conversion of the three oxygen carriers with addition of iron oxide with manganese-iron molar ration of 1:2 sintered at 950°C for 4 hours were measured. The reactivity was improved for most of the manganese ores after the proposed treatments. Reactivity results of the oxygen carrier based on South African (B) manganese-ore sintered at 1300°C for 6 hours are the most promising ones among all the tested Mn-ore-based samples with addition of calcium hydroxide. Oxygen carrier manufactured from Brazilian ore with Mn/Fe molar ratio of 2:1 sintered at 950°C for 4 hours showed the best methane conversion among the all samples with addition of iron oxide. Producing feasible oxygen carriers directly from ores would cut the cost of chemical looping combustion and could have a significant impact on its competitiveness among other carbon capture technologies.
Beskrivning
Ämne/nyckelord
Energi , Maskinteknik , Hållbar utveckling , Energy , Mechanical Engineering , Sustainable Development