Abstract:
The chemical looping combustion of coal with NiO/Al
2O
3 oxygen carrier was experimentally investigated in a 1 kW
th interconnected fluidized bed. The carbon conversion
ηC,coal, the conversion of gaseous products, the carbon capture efficiency
ηC,cap and the coal combustion efficiency
ηcombust were calculated and discussed. Several influencing factors including the temperature
tFR, excess air coefficy
α, the ratio of steam flow rate in the loopseal to the feed coal S
LS/C, the ratio of steam flow rate in the fuel reactor to the feed coal S
FR/C were examined. The results indicate that the increase in either
tFR or S
LS/C is favorable for increasing
ηC,coal and the conversion of gas products from coal gasification. A larger
α can also give a higher
ηC,coal. With the S
FR/C increasing from 0.8 to 1.6,
ηC,coal first increases and then decreases with the maximum at S
FR/C=1.2.
ηcombust has the same trends as
ηC,coal; it is mainly affected by the loss of carbon in the fly ash. Contrary to
α or S
LS/C, increasing
TFR can give a higher
ηC,cap.