Numerical study of pore structure effect on SO2-CaO reactions

doi:10.1016/j.cjche.2014.12.004

Abstract

Abstract: The effect of varying pore structures on the kinetics of SO₂-CaO reactions is not fully understood in the previous studies. Combining fractal pore model, gas molecular movement model and two-stage reaction model, a new desulfurization model is established in this paper. Fractal pore model is used to simulate CaO particle and gas molecular movement model is used to simulate gas diffusion in pores. Fractal dimension is used to characterize complexity of pore structure instead of tortuosity factor. It is found that the reaction is significantly affected by pore structures. A modulus ø is introduced to characterize the relationship between varying pore structures and apparent reaction parameters. And this relationship is verified by thermo-gravimetric analysis (TGA) data. Comparing to the previous models, the effect of varying pore structure on the kinetics of the reaction is described more accurately by the desulfurization model.

Key words: Desulfurization model, Gas diffusion, Fractal, Pore structure

摘要： The effect of varying pore structures on the kinetics of SO₂-CaO reactions is not fully understood in the previous studies. Combining fractal pore model, gas molecular movement model and two-stage reaction model, a new desulfurization model is established in this paper. Fractal pore model is used to simulate CaO particle and gas molecular movement model is used to simulate gas diffusion in pores. Fractal dimension is used to characterize complexity of pore structure instead of tortuosity factor. It is found that the reaction is significantly affected by pore structures. A modulus ø is introduced to characterize the relationship between varying pore structures and apparent reaction parameters. And this relationship is verified by thermo-gravimetric analysis (TGA) data. Comparing to the previous models, the effect of varying pore structure on the kinetics of the reaction is described more accurately by the desulfurization model.

关键词: Desulfurization model, Gas diffusion, Fractal, Pore structure

Liang Ma, Liyong Cao, Rong He. Numerical study of pore structure effect on SO₂-CaO reactions[J]. Chin.J.Chem.Eng., 2015, 23(4): 652-658.

Liang Ma, Liyong Cao, Rong He. Numerical study of pore structure effect on SO₂-CaO reactions[J]. Chinese Journal of Chemical Engineering, 2015, 23(4): 652-658.

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Numerical study of pore structure effect on SO₂-CaO reactions

Numerical study of pore structure effect on SO₂-CaO reactions

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