A generalized pore model for gas-solid reactions exhibiting pore closure



A model of pore structure evolution has been developed for gas-solid reactions exhibiting pore closure behavior. A cylindrical pore network of constant coordination number is used to represent the porous medium, and both discrete and continuous distributions of pore size are considered. The mathematical model takes into consideration the effects of pore overlapping and nonuniform pore growth, and follows the formation of inaccessible volume in the interior of the reacting particles by use of percolation theory concepts. The model is applied, along with an appropriate diffusion and reaction model, to the investigation of the transient behavior of calcined limestone particles in an environment of sulfur dioxide.