A bin assembly system comprising: at least one bin assembly comprising: a cylindrical bin (102, 702, 708, 714); a tapered hopper bottom arranged at a first end of the cylindrical bottom, the hopper bottom having a circular outlet (110, 920); a slide gate constructed to modulate material (704, 710, 716) exiting the hopper bottom outlet (110, 920) by displacing to expose portions of the outlet (110, 920); and a bin outlet insert (300, 500, 800, 900, 1000) having a rectangular opening (305, 516, 805, 908) disposed within the circular outlet (110, 920), wherein the bin outlet insert (300, 500, 800, 900, 1000) is constructed to convey material (704, 710, 716) in the cylindrical bin (702, 708, 714) through the rectangular opening (305, 516, 805, 908), thereby converting the circular outlet (110, 920) of the hopper bottom to a rectangular opening (305, 516, 805, 908), characterised in that the slide gate is coupled to the circular outlet (110, 920) and that the bin outlet insert (300, 500, 800, 900, 1000) is disposed within the tapered hopper bottom adjacent to the circular outlet (110, 920). at least one bin assembly comprising: a cylindrical bin (102, 702, 708, 714); a tapered hopper bottom arranged at a first end of the cylindrical bottom, the hopper bottom having a circular outlet (110, 920); a slide gate constructed to modulate material (704, 710, 716) exiting the hopper bottom outlet (110, 920) by displacing to expose portions of the outlet (110, 920); and a bin outlet insert (300, 500, 800, 900, 1000) having a rectangular opening (305, 516, 805, 908) disposed within the circular outlet (110, 920), wherein the bin outlet insert (300, 500, 800, 900, 1000) is constructed to convey material (704, 710, 716) in the cylindrical bin (702, 708, 714) through the rectangular opening (305, 516, 805, 908), thereby converting the circular outlet (110, 920) of the hopper bottom to a rectangular opening (305, 516, 805, 908), characterised in that the slide gate is coupled to the circular outlet (110, 920) and that the bin outlet insert (300, 500, 800, 900, 1000) is disposed within the tapered hopper bottom adjacent to the circular outlet (110, 920). a cylindrical bin (102, 702, 708, 714); a tapered hopper bottom arranged at a first end of the cylindrical bottom, the hopper bottom having a circular outlet (110, 920); a slide gate constructed to modulate material (704, 710, 716) exiting the hopper bottom outlet (110, 920) by displacing to expose portions of the outlet (110, 920); and a bin outlet insert (300, 500, 800, 900, 1000) having a rectangular opening (305, 516, 805, 908) disposed within the circular outlet (110, 920), wherein the bin outlet insert (300, 500, 800, 900, 1000) is constructed to convey material (704, 710, 716) in the cylindrical bin (702, 708, 714) through the rectangular opening (305, 516, 805, 908), thereby converting the circular outlet (110, 920) of the hopper bottom to a rectangular opening (305, 516, 805, 908), characterised in that the slide gate is coupled to the circular outlet (110, 920) and that the bin outlet insert (300, 500, 800, 900, 1000) is disposed within the tapered hopper bottom adjacent to the circular outlet (110, 920).