A flexible bulk container includes side walls coupled to a bottom wall. The side walls and the bottom wall generally enclose an interior space that is accessible through a top of the flexible bulk container for loading materials therein. A support structure includes elongate frame elements. Each of the frame elements may be attached to at least one of the side walls and is configured to support the at least one of the side walls generally upright so that the flexible bulk container is maintained in a generally open position. Each of the frame elements may be detachable from the respective at least one of the side walls. The flexible bulk containers and the support structures may be used in a waste management system for loading and sorting of bulk waste materials.