A device for clearing waste material from at least one storage container, which can be closed by a bottom valve and is arranged at the lower end of a vertical dump shaft that opens into a branch duct of a pneumatic conveying duct, the bottom valve comprising a vertically movable valve body which in its closed position closes the waste container outlet and in its open position enables the refuse collected in the container to be released into the conveying duct, the sidewall of the valve chamber being fitted with at least one opening through which the contents of the waste container can be emptied into the branch duct unless the opening is closed by the valve body.