단일 유효확산계수로 나타낸 동적 흡착탑의 분산일치 적용기준

송동익

HWAHAK KONGHAK, Vol.34, No.6, 813-816, December, 1996

Export Citation

단일 유효확산계수로 나타낸 동적 흡착탑의 분산일치 적용기준

Criterion for Variance Matching in Dynamic Adsorbers in Terms of Single Effective Diffusivity

송동익

초록

등고선 그림을 이용하여 단일 유효확산계수로 나타낸 분산일치식 성립기준을 보수적으로 θD_p/ R_p²>0.5로 설정하였으며 이 조건이 만족되는 경우 송[6]이 제안한 방법으로 거대 및 미세기공에서의 두 유효확산계수를 계산할 수 있다. 모델단순화의 경우에는 응답곡선의 왜곡도에 관계업싱 왜곡도일치식보다는 분산일치식을 이용하는 것이 바람직함을 확인하였다.

Criterion for applying the new estimation method for the macro- and micropore effective diffusivities suggested by Song[6] was determined conservatively as θDp/Rp2>0.5 in terms of the single effective diffusivity by comparing the contour plot between the single and the two diffusivity models. It was confimed that making use of variance matching instead of skewness matching is desirable for model simplification even when a response curve exhibits a high degree of asymmetry about mean.

Keywords:Moment Method;Effective Diffusivity;Variance Matching;Third Moment Matching

[References]

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Song DI, HWAHAK KONGHAK, 33(3), 328 (1995)
Schneider P, Smith JM, AIChE J., 14, 762 (1968)
Hashimoto N, Smith JM, Ind. Eng. Chem. Fundam., 12, 353 (1973)

[1] Johnson MFL, Stewart WE, J. Catal., 4, 248 (1965)

[2] Wakao N, Smith JM, Chem. Eng. Sci., 17, 825 (1962)

[3] Haynes HW, Catal. Rev.-Sci. Eng., 30, 563 (1988)

[4] Raghavan NS, Ruthven DM, Chem. Eng. Sci., 40, 699 (1985)

[5] Kim DH, AIChE J., 36, 302 (1990)

[6] Song DI, HWAHAK KONGHAK, 33(3), 328 (1995)

[7] Schneider P, Smith JM, AIChE J., 14, 762 (1968)

[8] Hashimoto N, Smith JM, Ind. Eng. Chem. Fundam., 12, 353 (1973)