기체유동층에서 슬러그 특성에 미치는 유속, 측정높이, 최소유동화상태의 층높이, 층직경, 입자특성의 영향을 고찰하기 위해 2개의 유동층(유동층 A: 내경 0.055m, 높이 2.0m, 유동층 B: 내경 0.1m, 높이 2.5m)에서 층물질로 모래(평균입경 0.286 mm)와 FCC(A: 평균입경 0.082 mm, B: 0.091 mm)를 사용하여 유속, 측정높이, 최소유동화상태의 층높이, 층직경 및 입자특성의 변화에 따른 슬러그 특성을 측정하였다. 측정된 최소슬러깅속도는 측정높이가 증가함에 따라 감소하였으며 최소유동화상태의 층높이와 측직경이 증가함에 따라 증가하였다. 최소슬러깅속도에 대한 입자특성의 영향은 층직경에 따라 다르게 나타났다. 층직경이 작은 경우에는 모래입자의 최소슬러깅속도가 FCC에 비해 크게 나타났으나 층직경이 큰 경우에는 FCC의 최소슬러깅속도가 모래에 비해 크게 나타났다. 슬러그 빈도는 유속이 증가함에 따라 감소하였으나 유속이 증가함에 따라 감소 경향이 둔화되었으며 측정높이와 최소유동화상태의 층높이가 증가함에 따라 감소하였고 층직경이 증가함에 따라 증가하였다. 슬러그 빈도에 미치는 측정높이의 영향은 최소유동화상태의 층높이가 증가함에 따라 감소하였다. 주어진 과잉기체유속에서 FCC입자의 슬러그 빈도가 모래 입자에 비해 크게 나타났다.

In order to understand the slugging regime comprehensively, the characteristics of slugging have been studied experimentally in gas fluidized beds. The onset velocity of slugging and the properties of slug were measured in gas fluidized beds(bed A: 0.055 m i.d., 2.0 m height, bed B: 0.1 m i.d. and 2.5 m height) using sand(specific surface mean diameter: 0.286 mm) and FCC(FCC A, specific surface mean diameter: 0.082 mm, FCC B, specific surface mean diameter: 0.091 mm) as bed materials with variations of gas velocity, height from the distributor plate, bed height at minimum fluidization, column diameter and particle properties. The minimum slugging velocity decreased with increasing height from the distributor plate, however, increased with increasing bed height at minimum fluidization and column diameter. However, the effect of particle properties was found to be dependent on the column diameter. The minimum slugging velocity of sand was higher than that of FCC in the column of 0.055 m inside diameter, however, that of FCC higher than that of sand in the column of 0.10 m inside diameter. The slug frequency decreased with increasing gas velocity, height from the distributor plate and bed height at minimum fluidization, however, increased with column diameter. The effect of gas velocity on slug frequency diminished as gas velocity increased. The effect of height from the distributor plate on slug properties decreased as the bed height at minimum fluidization increased. The slug frequency of FCC was higher than that of sand at the same excess gas velocity.

Gas-Solid Fluidization Minimum Slugging Velocity Slug Frequency

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