Abstract: Provided is an apparatus comprising a screen assembly for sifting powder including a rear feeding device, a first conveyor adapted to convey garbage bags from the feeding device to the screen assembly, an inclined board extended downwardly from a front end of the screen assembly, and a second conveyor provided below the board, the second conveyor being adapted to convey materials leaving the screen assembly to a subsequent station for processing; and a nonrigid, elongate object collection assembly extended from the rear of the screen assembly through the screen assembly to a point in front of the screen assembly, the object collection assembly including an elongate housing of rectangular section, a gable roof provided on the housing, a lengthwise gap provided on a top of the gable roof, and a container provided below a front end thereof for collecting nonrigid, elongate objects dropped therefrom.