A Study On Effect Of Characteristics Of Copper-Based Oxygen Carrier On Polycyclic Aromatic Hydrocarbons In Chemical Looping Combustion

Chinese energy consumption is vast in worldwide and the coal is the main source to meet the industry, agriculture and daily life through traditional combustion. But this way is not an excellent method because of the CO2 emission without separating and controlling to exacerbate the greenhouse effect and the global warming. Chemical-looping combustion (CLC) is considered a potential way proposed and studied by researchers to solve this problem based on its inherent ability to separating CO2 in the combustion process but the problem is that the reactivity and sustainable cycling capability of oxygen carrier are affected by deposit carbon forming.To study the interaction between Polycyclic Aromatic Hydrocarbons (PAHs) in flue gas and oxygen carrier, three kinds of oxygen carriers including mechanical mixing, impregnation and precipitation sedimentation and four kinds of coal samples including Anthracite,1#,2# and 3# Bituminous were prepared for experiments in quartz tube combustion reactor at different temperature of 600 ℃,700℃,800℃, 900℃and 1000℃ and vacuum degree of-0.09MPa. PAHs in flue gas and distribution of ring were measured in Gas Chromatograph with Flame ions detector (FID-GC), elements analysis of unused precipitation oxygen carrier was characterized through EDX and changes on microstructure of oxygen carrier and deposit carbon were characterized with SEM. Experiment results indicated that:1. The PAHs total in flue gas after combustion with impregnation oxygen carrier was least, so impregnation oxygen carrier showed the excellent property.2. The PAHs total in flue gas increased with the increasing percentage of volatile ranging from 7.2% to 33.29% in coal and the main distribution of ring were 3-ring products.3. The agglomeration and deposit carbon didn’t appear at 900 ℃, as a result 900℃ is the optimum temperature in CLC.4. Because of the higher content of volatile matter in coal, the lower fixed carbon content, the amount of deposit carbon on oxygen carrier after combustion decreased with increasing percentage of volatile ranging from 7.2% to 33.29% in coal, negative correlation was showed between the two variates.