상온 2단 선회류 유동층 연소로에서 1차 공기의 유량을 일정하게 유지하고 2차 공기의 유량만을 변화시키면서 상단에서 미세입자의 비산유출속도를 측정하였다. 상온2단 선회류 유동층에서 입자의 비산유출속도는 본 연구의 상단 가스공탑속도(UO2=0.1-0.35m/s) 범위에서 상단 공탑속도(UO2)가 증가함에 따라 서서히 증가하다가 상단 공탑속도 0.3m/s이상에서 급격한 증가를 보였다. 또한 비산유출속도는 선회강도에 크게 의존하였으며 선회강도 증가에 따라 지수함수적으로 감소하였다. 상온 2단 선회류 유동층에서 입자의 비산유출속도상수는 공탑속도 증가에 따라 증가하였으며 본 연구의 유속조건하에서 83-88㎛ 범위의 분리한계입경을 나타내었다. 상온 2단선회류 유동층에서 입자의 비산유출속도상수는 상단 과잉공기속도(UO2-Umf)와 dp/dp100에 대하여 다음과 같은 상관관계를 나타내었다.
K*(dP/ρg(UO2-Umf)=337.7(UO2-Umf)3.6exp(-7.18dP/dP100)+2.54(UO2-Umf)6
The elutriation rate of fine particles were measured in a cold model Two-Stage Swirl-Flow Fluidized Bed Combustor(TSSF-FBC). The range of secondary air flow rate was varied from 0.1m/s to 0.35m/s while the primary air flow rate was kept to a constant value of 1m/s. It was found that the elutriation rate of fine particles slightly increased with the secondary superficial air velocity. When the secondary superficial air velocity exceeded over 0.3m/s, However, the elutriation rate rapidly increased. The elutriation rate of fine particles was strongly dependent upon the swirl intensity. It was exponentially decreased as the swirl intensity increased. The elutriation rate constant increased with the secondary superficial air velocity, and the critical particle diameters were in range of 83-88㎛. Under the experimental conditions, the elutriation rate constant of fine particles can be correlated with secondary excess air velocity(UO2-Umf) and dp/dp100 as follows;
K*(dP/ρg(UO2-Umf)=337.7(UO2-Umf)3.6exp(-7.18dP/dP100)+2.54(UO2-Umf)6
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