<p>Solids particles are conveyed hydraulically by first mixing the solids particles with a liquid in order to form a viscous material of substantially uniform consistency. This viscous material is then introduced or injected into a flowing hydraulic medium that had been substantially free of solids prior to this viscous material injection in order to form a hydraulically conveyed flow. Variations in conduit cross-section at or near the location of viscous material injection may be provided in order to enhance turbulance and suspension of solids within the hydraulically conveyed flow.</p>
