Issue link: https://www.e-digitaleditions.com/i/1277345
9 www.spirofl ow.com Bulk bag tensioning Make sure your bulk bag unloaders are designed to properly tension the bulk bag, and any associated lin- er, so that the complete contents of each bag are dis- charged. Residual material trapped in bag creases and folds can potentially increase dusting and spillage during bag removal. Enclosed access chamber Nearly half of all material spillage and dusting occurs during the bag spout untying process. Controlling dust becomes a much bigger challenge in a case where the material is free fl owing. Look for a bulk bag unloader design where the bag spout access chamber is enclosed and keeps the chamber under a slight negative pressure to minimize dusting issues and contain spillage. For haz- ardous material applications, a glove box arrangement, instead of access chamber doors, should be considered to prevent operator exposure. Sanitary spout docking Positive pressure docking arrangements can ensure complete material containment for a sanitary discharge process. This will also allow for effi cient bag stretching at the end of the discharge cycle. Consider this design option with or without the access chamber. Effi ciently docking a spout can require some dexterity, but per- forming this operation in an enclosed area can com- pensate for operator errors. Empty bulk bag removal Dusting can often occur during the empty bag removal cycle. Consequently, tightly tying off the bag spout prior to bag removal is imperative. Consider adding a bag-col- lapsing feature that uses a dust collector to evacuate the bag and rid the environment of suspended dust. Again, an enclosed access chamber facilitates the capture of any fugitive dust during this step in your operation. Downstream process optimization Allowing suffi cient time for the operator to perform each necessary step in the bulk bag unloading process is es- sential. Planning for strategic time buffers throughout the process can eliminate downtime and allow the oper- ator to properly perform all the necessary operations for a dust-free bulk bag unloading operation. PBE