Measurement of liquid holdup and axial dispersion in trickle bed reactors using radiotracer technique

• Autorzy: Pant H. , Saroha A. , Nigam K.
• Języki publikacji: EN

Abstrakty

EN

The holdup and axial dispersion of aqueous phase has been measured in trickle bed reactors as a function of liquid and gas flow rates using radioisotope tracer technique. Experiments were carried out in a glass column of inner diameter 15.2´10-2 m column for air-water system using three different types of packings i.e. non-porous glass beads, porous catalysts of tablet and extrudate shape. The range of liquid and gas flow rates used were 8.3´10-5-3.3´10-4 m3/s and 0-6.67´10-4 m3/s, respectively. Residence time distributions of liquid phase were measured and mean residence times were determined. The values of liquid holdup were calculated from the measured mean residence times. It was observed that liquid holdup increased with increase in liquid flow rates and was independent of increase in gas flow rates used in the study. Two-parameter axial dispersion model was used to simulate measured residence time distribution data and values of mean residence time and Peclet number were obtained. It was observed that values of Peclet number increases with increase in liquid flow rate for glass beads and tablets and remains almost constant for extrudates. The values of mean residence time obtained from model simulation were found to be in good agreement with the values measured experimentally.

Słowa kluczowe

EN

axial dispersion model; holdup; mean residence time; Peclet number; residence time distribution; trickle-bed reactor

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2000
• Tom: Vol. 45, nr 4
• Strony: 235--241
• Opis fizyczny: Bibliogr. 9 poz., rys.

Twórcy

autor

Pant H.

• Isotope Applications Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India, Fax: [phone]

autor

Saroha A.

• Isotope Applications Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India, Fax: [phone]
• Department of Chemical Engineering, Thapar Institute of Chemical Engineering and Technology, Patiala 144001, India

autor

Nigam K.

• Department of Chemical Engineering, Indian Institute of Technology, Hauz Khas, New Delhi 110 016, India

Bibliografia

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• 2. Fu Meng Shyang, Chung-Shung Tan (1996) Liquid holdup and axial dispersion in trickle bed reactors. Chem Eng Sci 51:5357–5361
• 3. Gianetto A, Specchia V (1992) Trickle bed reactors: state of art. and perspectives. Chem Eng Sci 47:3197–3213
• 4. Guidebook on radioisotope tracers in industry (1990) Technical Report Series No. 316. IAEA, Vienna
• 5. Levenspiel O (1996) Chemical reaction engineering. 2nd edn. Wiley, New York
• 6. Michelsen M. L. (1972) A least-squares method for residence time distribution analysis. Chem Eng J 4:171–179
• 7. Residence Time Distribution software analysis (1996) Computer Manual Series No. 11. IAEA, Vienna
• 8. Saroha A. K., Nigam K. D. P. (1996) Trickle bed reactors. Reviews in Chemical Engineering 12:207–347
• 9. Saroha A. K. (1997) Studies on multiphase reactors. Ph.D. Thesis, Indian Institute of Technology, Delhi, India