The constitutive equations which characterize a porous medium are in general established from a study of the filter cakes, but the inherent differences in the processes for forming the cakes by means of filtration or sedimentation, make it difficult to properly characterize these sediments. Dynamic data of a batch sedimentation process as a function of variation in the height of the interfaces and the solid concentration profile, have been used to evaluate the parameters of constitutive equations for sediments. Starting from experimental data and from a model of the batch sedimentation process, and considering the coexistence of two distinct zones during the test - that of free settling and that of compression, coupled with balanced equations of global mass and height restriction-simulations were made and the parameters of the equations were evaluated by adjusting the results of the model to the experimental data.