Compression of deformable gel particles

In order to study the deformation behavior of deformable particles under hy draulic drag and mechanical load such as in filtration, a number of in situ strengths of single calcium-alginate gel particle and inter-particle conta ct modes among gel particles were explored. A linear viscoelastic contact m odel based upon the Hertz theory was proposed to describe the deformation b ehavior 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 b etween particles. Both theoretical and experimental results show that the m odified Hertz theory combined with the linear viscoelastic model can be use d to predict the mechanical behaviors of gel particle under mechanical comp ression well. Experimental results also demonstrate that a given mechanical load would result in a higher degree of deformation of particles than unde r the same amount of hydraulic drag. Based upon the theoretical derivation and the verification of experimental results, a correlated relationship bet ween specific surface area ratio and bed porosity, epsilon, with a validate d range of 0.05 < epsilon < 0.5 is presented. (C) 2001 Elsevier Science B.V . All rights reserved.