| Project/Area Number |
06650853
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
化学工学一般
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| Research Institution | TOKYO INSTITUTE OF TECHNOLOGY |
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Principal Investigator |
KOSUGE Hitoshi Tokyo Institute of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (70170256)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1995: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1994: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Keywords | Distilllation / Mass Transfer / Heat Transfer / Calculation Method |
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| Research Abstract |
The objectives of this study are to investigate the effect of operating conditions on the heat and mass transfer rates in heterogeneous azeotropic distilllation, and to develop a new calculation method for heterogeneous azeotropic distilllation based on the heat and mass transfer rates.
A new wetted-wall column with two stills is set up, where oilish and aqueous liquids of thr feed are heated separately in the stills so as to vary the inlet vapor concentrations. The experiments of heterogeous azeotropic distilllation for the ethanol-benzene-water system are carried out undet total reflux conditions with wide ranges of vapor flow rates and concentration. The dimensionless vapor-phase diffusion flux of each component obtained in an oil-rich liquid region shows good agreement with the theoretical values of the mass transfer rates with laminar flow in a circular tube. However the observed vapor phase diffusion flux obtained from an water-rich liquid show larger values than the theory.
A new calculation method for heterogeneous azeotropic distilllation is developed based on heat and mass transfer. The simulation of heterogeneous azeotropic distilllation shows a large difference of concentration driving force of benzene and water between the bottom and top of the column, and also shows the variation of the concentration driving forces of those components along the column. This may cause the larger mass transfer rates than the theoretical values. The representative concentration driving force obtained from the distilllation experiments might no represents the real concentration driving force. These results indicate another experiment with a shorter distilllation column. Actually, the calculated vapor an liquid concentrations and reflux flow rates in whole two liquid regions, while the average diffusion flux in and oil-rich two liquid region are still larger than the theoretical values.
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