Abstract: A system is disclosed for continuously feeding and burning solid waste derived fuel (SWDF) material in the calciner of a calciner kiln comprising a calciner combustion chamber, a kiln feed for feeding raw kiln material to the calciner combustion chamber, and a waste material feed system for continuously feeding SWDF material at a controlled rate to the calcine combustion chamber for burning. A burner having a burner fuel control for feeding a control fuel to the burner to control the temperature in the calciner combustion chamber. A riser duct is connected between a charge end of the rotary kiln and the calciner. The combustion chamber introduces hot combustion gas generally above the riser duct for mixing with the hot kiln gas flowing through the riser duct at a high velocity for further calcining of the raw kiln materials and burnout of the SWDF material.