关键词: 碳捕集, 化学链燃烧, 化石能源, 煤, 铁基载氧体, 移动床反应器

Abstract: Driven by increasing demands for energy and concerns for climate change, more attention are paid to the development of clean, efficient, and economical technologies for energy conversion, among which chemical looping is considered as a promising alternative for fossil fuel conversion. Chemical looping processes enable highly efficient in situ CO₂ capture in oxidation of carbonaceous fuels by making use of solid oxygen carriers. The Ohio State University (OSU) has developed a unique chemical looping technology utilizing iron-based oxygen carrier and moving bed reactors. Thermodynamic analysis shows that counter-current moving bed reactor can maximize oxygen carrier conversion while fully converting fuels, enabling high purity H₂ production by iron-steam reaction. OSU chemical looping is highly flexible for converting a variety of gaseous and solid fuels to electricity, H₂, and chemicals with CO₂ captured. To date, the syngas chemical looping (SCL) technology and the coal direct chemical looping technology has been successfully operated for more than 850 h in total on two 25 kW_th sub-pilot units. A 250 kW_th high pressure SCL pilot unit is constructed at National Carbon Capture Center and will be put into operation in 2014.

Key words: carbon capture, chemical looping, fossil fuel, coal, iron-based oxygen carrier, moving bed reactor