The flat or axisymmetrical two-phase streams intruding into reactor-capacity filled by liquid are considered. Streams are loaded with solid pollutant particles of different diameters. The degree of nonequilibrium of streams are researched - a deflection of particles paths from corresponding fluid lines. The analytical solutions for fluid flow are obtained. Paths of different size particles are obtained by numerical simulations. It was shown that from determine size of particles there may be local zones of slag on bottom of reactor. Places and forms of this deposition zones fully depends on conditions of process organization.