Based on the actual size and operation parameters of COREX melter gasifier and the similarity theory，as caled COREX melter gasifier model is established to study the burden movement.The polyethylene particles and mung bean are used as the packed burden and traceparticles，respectively.The effects of blast volume and discharging rate on flow pattern and trajectory are studied in detail. The results reveal that with the increase of discharging rate，the residence time decreases，the top position of deadman reduces，and the descending of burden movement becomes uneven.With the increase of the blast volume，the upper burden descends more even.Under abnormally discharging condition，the burden movement in meltergasifier would become uneven，which would cause uneven gas distribution in the furnace.The flow behavior in one half of the model appears to be independent of the other half.Particles under deadman descending at the slowest velocity tend to bend to the outlet.Particles above the raceway descend at the fastest velocity，and the blast causes the residence time to be reduced.Particles being close to the furnace wall descend along the wall until they get close to the outlet and then bend.