A liner for use in a waste sorting and disposal system is configured for placement in a container is provided. The liner includes an internal space and an opening that provides access to that internal space. In some embodiments, the liner may also include a machine-readable identification key that is configured to identify a type of waste that the liner may receive. In some embodiments, the machine-readable key is optical, color-coded, alphanumeric or graphical. The liner can include one or more closure members to allow a user to securely seal the liner when it is removed from the container. In some embodiments, the liner can include a flange, lip, hook or other protrusion to secure its position relative to a container.