The dry dispersion is the deglomeration of fine aggregate particles in an air stream. It is necessary for deglomeration that the existing van der Waals adhesive forces are smaller than the dispersion force. The angle-dependent dispersion force on a model aggregate particle was theoretically analyzed for the acceleration in an air stream. The stress by the angle-dependent dispersion force and the centrifugal force is compared with the mean adhesive force of the agglomerate. The derived dispersion model is able to give a decision whether the model agglomerate can be dispersed due to the stress in the flow. The theoretical results were checked and proved by experiments with three materials. A high stress and a real rough particle surface is the prerequisite for dispersion of fine particles.