Compression of deformable gel particles

In order to study the deformation behavior of deformable particles under hydraulic drag and mechanical load such as in filtration, a number of in situ strengths of single calcium-alginate gel particle and inter-particle contact modes among gel particles were explored. A linear viscoelastic contact model based upon the Hertz theory was proposed to describe the deformation behavior of deformable gel particles, The effect of particle deformation due to frictional drag and mass of particles on the reduction of porosity was studied to examine how this variation led to the increase in contact area between particles. Both theoretical and experimental results show that the modified Hertz theory combined with the linear viscoelastic model can be used to predict the mechanical behaviors of gel particle under mechanical compression well. Experimental results also demonstrate that a given mechanical load would result in a higher degree of deformation of particles than under the same amount of hydraulic drag. Based upon the theoretical derivation and the verification of experimental results, a correlated relationship between specific surface area ratio and bed porosity, epsilon, with a validated range of 0.05 < epsilon < 0.5 is presented. (C) 2001 Elsevier Science B.V. All rights reserved.