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Show PG. 1 BENCH-SCALE TESTING ON 02/C02 COMBUSTION FOR C02 RECOVERY Shigehiro MIYAMAE, Takashi KIGA and Shin-ichi TAKANO IHI, Ishikawajima-Harima Heavy Industries Co., Ltd. 2-16, 3-chome, Koto-ku, Tokyo 135, Japan and Koji OMATA and Naokazu KIMURA EPDC, Electric Power Development Co., Ltd. 15-1, 6-chome, Chuoh-ku, Tokyo 135, Japan ABSTRACT Evaluating the characteristics of burnout efficiency, NOx conversion and flame behavior on pulverized coal firing with 02/flue gas recycling combustion for CO2 recovery, a bench-scale testing was conducted using a 1.2MWt tunnel type test furnace. From the viewpoint of the plant safety on full scale 02 combustion with recycled flue gas, pulverized coal was transported by flue gas as a primary 'stream and 02 conc. in a. secondary stream was also limi ted to be less than 35%. Consequently, these limi tations caused poor flame stabili ty and char burnout due to lowering flame temperature by flue gas recycling. Enhancing the char burnout performance, therefore, an attempt was made to supply a part of pure 02 as a tertiary stream to the burner throat through an 02 injection nozzle. When 02 conc. in the secondary stream kept constantly to above limited value, the increase of the tertiary stream apparently improved the flame stability and the char burnout efficiency, as was expected. NOx emissions was not affected signif icantly by the presence of the tertiary stream, and it was found that lower NOx conversion was obtainable on 02/C02 combustion. |