Korean Journal of Chemical Engineering

, Volume 17, Issue 1, pp 22–26 | Cite as

Drying of water treatment process sludge in a fluidized bed dryer

  • Yong-Seop Shin
  • Hee Chul Kim
  • Hai Soo Chun


The drying characteristics of water treatment process (WTP) sludge were investigated with a fluidized bed. The equilibrium moisture ratio of WTP sludge increased with relative humidity and decreased with temperature of drying air. However, equilibrium moisture ratio of WTP sludge was more sensitively dependent on relative humidity than temperature of drying air. When the sludge was dried in a batch fluidized bed, the drying rate of sludge decreased as the moisture ratio of sludge in the bed decreased. The periods of constant drying rates were apparently not observed on the drying rate curves. In addition, the maximum drying rates were increased with bed temperature and superficial air velocity. As the fluidized bed was operated continuously, the degree of drying of WTP sludge increased with bed temperature but was weakly dependent on superficial air velocity. However, the drying efficiency was decreased with bed temperature and relatively insensitive to superficial air velocity and increased with feed rate of sludge.

Key words

Fluidized Bed Dryer Waterworks Sludge Equilibrium Moisture Ratio Drying Rate Drying Efficiency 


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Copyright information

© Korean Institute of Chemical Engineering 2000

Authors and Affiliations

  1. 1.Dept. of Environ. Eng.Kyungsung UniversityPusanKorea
  2. 2.Dept. of Chem. Eng.Korea UniversitySeoulKorea

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