Trapped Components in Distillation Columns: Sometimes Changing Operating Conditions Can Solve Your Problem(Abstract)

摘要

Minor components trapped in distillation towers can sometimes be a source of major problems. In some cases, the minor components may be reactive inside the column environment and react to form higher molecular weight species and polymers that may not be soluble in the liquid phase in certain sections of the column. The presence of solids inside the column often results in unpredictable vapor-liquid contact behavior and results in operational headaches that could include adverse effects on product quality and increased maintenance cost and downtime for plants. Often solutions explored for such a problem comprises of methods that enable operations to deal with solids after they have formed (i.e., modification of trays and internals that deal with solids more easily) and/or minimizing the formation of the polymer species (i.e., injection of additives to inhibit the reactive species or disperse the polymers). Typically, these solutions tend to be expensive and prove to be somewhat of a "Band Aid" for the real problem. One option is to take a close look at the column operation and explore ways in which the minor component can be purged from the process. A case study in which the minor component trapped in a column was purged effectively by a very slight change in operating conditions will be discussed in detail.