| Abstract: | The production of ultrapure water by ion exchange requires thorough mixing of cationic and anionic resins. In many cases the resins are regenerated requiring bead-type separation prior to chemical treatment with the respective acid or base. Resin separation is predictable based upon backwash conditions, resin properties, and system geometry. An important factor in an accurate model is the drag coefficient relationship. There are numerous models available and the choice can result in significant prediction differences. This article presents data for resin bead fall within a full-depth column and discusses which drag coefficient model is most applicable. The expression by Massey showed the best agreement for this application. |
