투과증발공정에서 투과액의 상전이에 의한 온도강하가 물질전달에 미치는 영향

송규민; 이철행; 홍원희; 박병건; 장호남

HWAHAK KONGHAK, Vol.34, No.6, 797-805, December, 1996

Export Citation

투과증발공정에서 투과액의 상전이에 의한 온도강하가 물질전달에 미치는 영향

Effect of Temperature Drop by Phase Transition of Permeate on Mass Transfer in Pervaporation Process

송규민, 이철행, 홍원희, 박병건, 장호남

초록

투과증발모듈에서 상전이에 의한 온도강하가 물질전달에 미치는 영향과 유속의 변화에 의한 겉보기 농도분극이 일어나는 현상을 열공급비가 증가할수록 모듈내 온도강하가 커져 물질전달의 감소를 보였다. 또한 공급액의 유속이 감소할수록 모듈내 온도강하는 커졌으며 이는 물질전달의 감소로 나타나게 되어 상전이가 없는 비슷한 막공정에서의 농도분극과 유사한 현상을 보여주게 된다. 농도분극에 대한 기존식과의 비교를 통하여 온도강하에 의한 물질전달감소가 무시할 수 없음을 보였다.

The effect of the temperature drop by phase transition on mass transfer in prevaporation module and the phenomenon of the apparent concentration polarization by the change of flow rate were discussed in term of the heat supply ratio defined in this study. The heat supply ratio indicates the relative amount of heat supplied from retentate form phase transition of permeate. With experiments, the mass transfer was decreased with increasing of the feed temperature for phase transition of permeate. With experiments, the mass transfer was decreased with increasing of the feed temperature and the heat supply ratio because of higher temperature drop. As the feed flow rate was decreased, the temperature drop was increased and the mass transfer was decreased. This phenomenon has a similarity of the concentration polarization in the case of other membrane processes without phase transition. It was shown that the effects of the temperature drop on mass transfer were not negligible from the comparison of the proposed formular for the concentration polarization.

Keywords:Temperature Drop;Phase Transition;Mass Transfer;Pervaporation;Heat Supply Ratio;Cut Ratio;Concentration Polarization

[References]

Rautenbach R, Albrecht R, J. Membr. Sci., 7, 203 (1980)
Rautenbach R, Albrecht R, J. Membr. Sci., 25, 25 (1985)
Daubert TE, "Chemical Engineering Thermodynamics," McGraw-Hill, 421 (1985)
Mattiasson E, Sivik B, Desalination, 35, 59 (1980)
Psaume R, Aptel P, Aurell Y, Mora JC, Bersillon JL, J. Membr. Sci., 36, 373 (1988)
Raghnath B, Hwang ST, J. Membr. Sci., 65, 147 (1992)
Gref R, Nguyen TQ, Neel J, Sep. Sci. Technol., 27(4), 467 (1992)
Dotremont C, VandenEnde S, Vandommele H, Vandecasteele C, Desalination, 95, 91 (1994)
Won JM, Ha BH, HWAHAK KONGHAK, 33(6), 756 (1995)
Aimar P, Howell JA, Clifton MJ, Sanchez V, J. Membr. Sci., 59, 81 (1991)
Howell JA, Sanchez V, Field RW, "Membranes in Bioprocessing-Theory and Applications," Chapman & Hall, Cambridge (1993)

[Referenced By]

[1] Rautenbach R, Albrecht R, J. Membr. Sci., 7, 203 (1980)

[2] Rautenbach R, Albrecht R, J. Membr. Sci., 25, 25 (1985)

[3] Daubert TE, "Chemical Engineering Thermodynamics," McGraw-Hill, 421 (1985)

[4] Mattiasson E, Sivik B, Desalination, 35, 59 (1980)

[5] Psaume R, Aptel P, Aurell Y, Mora JC, Bersillon JL, J. Membr. Sci., 36, 373 (1988)

[6] Raghnath B, Hwang ST, J. Membr. Sci., 65, 147 (1992)

[7] Gref R, Nguyen TQ, Neel J, Sep. Sci. Technol., 27(4), 467 (1992)

[8] Dotremont C, VandenEnde S, Vandommele H, Vandecasteele C, Desalination, 95, 91 (1994)

[9] Won JM, Ha BH, HWAHAK KONGHAK, 33(6), 756 (1995)

[10] Aimar P, Howell JA, Clifton MJ, Sanchez V, J. Membr. Sci., 59, 81 (1991)

[11] Howell JA, Sanchez V, Field RW, "Membranes in Bioprocessing-Theory and Applications," Chapman & Hall, Cambridge (1993)