Abstract: Simulation experiments were carried out to compare the main differences between bubbling and jetting regimes during submerged powder injection. An Aqueous Particle Sensor (APS) was first used for direct measurements to detect size of the injection plume, particle penetration and dispersion into liquid and gas entrainment in jet flow. The effect of gas and powder flow rates (powder/gas loading ratio) were the main parameters for determining the injection regimes and particle behavior.