The interaction between components during segregating fluidization of two-solid mixtures is shown to be an intrinsic feature of their mechanism of suspension. Separate force balances on either mixture component lead to assessing the individual contribution of the two solids to the total pressure drop. An analytical expression for the interaction force is thus obtained that explains why the complete fluidization of the mixture is possible at a velocity lower that the higher u(mf) of the two components and how the roles of 'flotsam' and 'jetsam' are attributed to them during the process of segregation. The theoretical expressions for the initial and final fluidization velocity of a binary mixture provided by this more insightful method of analysis are identical to those discussed in previous works and validated by a wide variety of experimental results. (C) 2014 Elsevier B.V. All rights reserved.