Method and device for charging processing plants

A device for charging combustion furnaces, the device comprising:

• a drum mixer for mixing liquid and solid components together in a non-pressurized state, wherein the liquid components are selected from the group of oil, oil sludge and combinations of oil and oil sludge, and the solid components are selected from the group of plastics, metals, silicates and combinations thereof to form a process material mixture to be fed into the combustion furnace;
• a first worm screw conveyor for lifting the process material mixture from the drum mixer and transferring the process material mixture in a non-pressurized state along a feed path from the mixer to a location proximate the combustion furnace;
• a pump for pressurizing the process material mixture received from the worm screw conveyor and having an outlet in communication with the combustion furnace;
• and
• a process material return created by a motor driven second worm screw conveyor separate from the material feed path so that when operation of the furnace is interrupted, the non-pressurized process material mixture in the first feed worm conveyor can be returned to the mixer along a material return path so that the solid components do not settle and clog in the first worm screw conveyor.