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32 July 2020 Tablets & Capsules center (yellow line) causes even more of the material to be outside the allowable limits. However, placing the feed inlet location at some point between the center and the wall (blue line) causes 99 percent of the material to fall within the allowable limits. The optimal configuration for the feed inlet location is summarized in Figure 11. This suggests that, for an API concentration of 10 percent, the best feed inlet location would be a point about 175 millimeters from the center- line of the feed hopper. Summary Measuring a formulation's segregation profile can help formulators and design engineers determine if the mate- rial is prone to segregation in any feed process. If the standard deviation of these segregation measurements (the segregation intensity) for the key components is less than about 3.3 percent, the formulation can often be used in any process with minimal segregation problems. If the segregation intensity values are larger than 3.3 percent, some process modification will be required to mitigate segregation problems. Ideally, processes should use proper mass flow bins with a velocity profile compatible with the material's mea- sured segregation patterns, enabling 100 percent of the final product to meet the allowable CU constraints. How- ever, in some cases, small modifications to a less-than-op- timal funnel flow hopper can reduce the segregation enough to keep the CU within allowable limits. T&C Dr. Kerry Johanson is chief operations officer of Material Flow Solutions (352 379 8879, www.matflowsol.com). He holds a PhD in chemical engineering from Brigham Young University and has more than 40 years of experience solving bulk powder and granule handling problems. The company specializes in material property testing and analysis and designing or retrofit- ting material handling systems to optimize production. Figure 11 Optimal feed inlet location for metering feeder device (10 percent API concentration) Segregation index (%) 100 90 80 70 60 50 40 30 20 10 0 Feed inlet offset (millimeters) 0 50 100 150 200 250 Offset AVAILABLE NOW: T&C's Solid Dosage Sourcebook spotlights top companies that supply equipment, materials, outsourcing, and expertise to manufacturers of pharmaceuticals and dietary supplements. A multifunctional mineral excipient Omyapharm ® 500 - OG Omya Consumer Goods omya.com info.pharma@omya.com · Very good absorption capacity · Excellent compactability · High mechanical stability · Faster disintegration · Lower ejection forces · Mechanical binding