A screw conveyor for introducing organic matter into a biogas digester that is under internal gas pressure. A biogas plant may be provided with such a screw conveyor, and methods for feeding organic solids to such a biogas plant may be performed. A plug section of the screw conveyor has an expansion region in which the passage cross-section between the conveying screw and the screw pipe widens in the conveying direction and a constriction region located downstream from the expansion region, in which the passage cross-section between the conveying screw and the screw pipe is reduced in the conveying direction.

A screw conveyor for introducing organic matter into a biogas digester that is under internal gas pressure. A biogas plant may be provided with such a screw conveyor, and methods for feeding organic solids to such a biogas plant may be performed. A plug section of the screw conveyor has an expansion region in which the passage cross-section between the conveying screw and the screw pipe widens in the conveying direction and a constriction region located downstream from the expansion region, in which the passage cross-section between the conveying screw and the screw pipe is reduced in the conveying direction.