Experimental Study of Oxygen-enriched Combustion Technology on a CFB Test-facility

摘要

Oxygen-enriched combustion technology is using pure oxygen instead of air and recycling most of flue gas, exhausting a small fraction of flue gas. Oxygen-enriched combustion technology is one of the promising new clean coal combustion technologies because of its easy CO_2 recovery, easy SO_2 treatment and low NO_x emission. Up to now, most experiments and theoretical studies on oxygen-enriched combustion technology are focused on pulverized coal furnaces. Oxygen-enriched combustion technology on CFB would obtain better effects due to its combining the advantage of CFB and oxygen-enriched combustion technology. Experiments of coal combustion on a CFB test-facility in O_2/N_2 or O_2/CO_2 mixtures were analyzed in the paper. Experimented oxygen concentration in once-through O_2/N_2 or O_2/CO_2 mixtures was 21%, 25%, 29% and 35%. All experimental condition was with same coal feeding, but gross air flow was reduced with the increasing of oxygen concentration. The excess oxygen in flue gas was kept about 5%.Characteristics of coal combustion, pollutants emission and desulfuration efficiency were compared. This would be an important preparation for industrialized application of oxygen-enriched combustion technology on CFB boilers.