Permeability analysis and seepage process study on crystal layer in melt crystallization with fractal and porous media theory

Abstract

In this paper a porous media seepage model was applied to analyze the permeability and study the seepage process of crystal pillar formed in the preparation of electronic grade phosphoric acid (EGPA). By inspecting the seeping process, the structure parameter of crystal pillar could be obtained. Two basic ideal models (perfectly separated model and perfectly connected model) were presented and a characterized factor φ was introduced to modify the model. A good simulation result was obtained which met the experiment result well. The relationship between φ and permeability were also discussed. The characterized factor φ showed potential application on optimizing process.

Keywords

melt crystallization / porous media / fractal / permeability / hyperpure material / simulation

References

[1] Kim K J. Purification of phosphoric acid from waste acid etchant using layer melt crystallization. Chemical Engineering & Technology, 2006, 29(2): 271-276

[2] Xiao L H, Zeng B. Research advances on electronic grade phosphoric acid. Yunnan Chem Technol, 2007, 34: 60-63 (in Chinese)

[3] Jumikis A R. Soil Mechanics. Florida: Robert E. Krieger Publishing Company. Inc., 1984, 51-67

[4] Kaviany M. Principles of Heat Transfer in Porous Media. 2nd ed. New York: Springer-Verlag, 1995, 15-63

[5] Panfilov M. Macroscale Models of Flow through Highly Heterogeneous Porous Media. London: Kluwer Academic Pub, 2000, 1-47

[6] Balhoff MT, Thompson K E. A macroscopic model for shear-thinning flow in packed beds based on network modeling. Chemical Engineering Science, 2006, 61(2): 698-719

[7] Yu B, Cheng P. Fractal models for the effective thermal conductivity of bi-dispersed porous media. Journal of Thermophysics and Heat Transfer, 2002, 16(1): 22-29

[8] Yu B, Cheng P. A fractal permeability model for bi-dispersed porous media. International Journal of Heat and Mass Transfer, 2002, 45(14): 2983-2993

[9] Ross W H, Jones R M. The solubility and freezing-point curves of hydrated and anhydrous orthophosphoric acid. Journal of the American Chemical Society, 1925, 47(8): 2165-2170

[10] Cheng N L, Hu S W. Solvents Handbook. 4th ed. Beijing: Chemical Engineering Press, 2008

[11] Yu B, Li J. Some fractal characters of porous media. Fractals, 2001, 9(3): 365-372

[12] Yu B M, Li J H. A geometry model for tortuosity of flow path in porous media. Chinese Physics Letters, 2004, 21(8): 1569-1571

[13] Yu B M. Fractal character for tortuous streamtubes in porous media. Chinese Physics Letters, 2005, 22(1): 158-160

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg