Drying in a desiccant wheel dehumidification system-assisted hot air dryer: desiccant wheel effectiveness and carrot drying

12th TSAE International Conference

Cheevitsopon, E.^1 ; Jongyingcharoen, J.S.^2

Food Engineering Department, Faculty of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand^1

Agricultural Engineering Department, Faculty of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand^2

关键词: Dehumidification system;    Desiccant wheels;    Drying temperature;    Heat exchanging;    Hot-air dryers;    Regeneration process;    Rotational speed;    Specific adsorption;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/301/1/012046/pdf
DOI  :  10.1088/1755-1315/301/1/012046

来源: IOP

【 摘 要 】

A desiccant wheel dehumidification system was used in this study to reduce humidity of the air supplied to a hot air dryer. Desiccant wheel effectiveness was determined based on the ideal adiabatic dehumidification process. Best results of adiabatic dehumidification effectiveness and adiabatic enthalpy effectiveness in the range of 0.89 to 0.99 were achieved. Specific adsorption of silica gel in the desiccant wheel was rotational speed dependent. The desiccant wheel system could reduce the relative humidity from 70 to 44%. Drying of cylindrical carrot in the desiccant wheel dehumidification system-assisted hot air dryer was also conducted in this study. The drying temperatures were varied from 80 to 120°C. The desiccant material regeneration process reused exhaust drying air for heat exchanging with the regenerating air, higher drying temperature caused higher moisture evaporated from the desiccant material. Comparing between dehumidified hot air drying and conventional hot air drying, greater drying rates of dehumidified hot air drying were achieved at the drying temperatures of 100 and 120°C.