A unit procedure in SuperPro Designer is defined as a sequence of actions (called operations) taking place within the same piece of equipment. When modeling a batch process (also known as batch recipe), you may think of a (batch) unit procedure as simply a set of sequential operations (like charge A, charge B, heat, stir, react, transfer out). Since a single unit procedure is represented by a single icon in a flowsheet of SuperPro Designer, you can lump as many or as few operations within a single unit procedure. If you use a single piece of equipment (some kind of vessel most likely) over and over during the execution of a recipe from beginning to end, you could - in principle - represent everything that takes place inside that vessel as a single unit procedure.
Every unit procedure is carried out in some kind of main equipment (Reactor, Fermentor, Diafilter, Nutsche filter, etc.). Clearly, two or more unit procedures can be assigned to take place in the same vessel (you must make sure though, that they are scheduled carefully so that their occupation times do not overlap). The types of operations that can be included in a unit procedure depend on the type of equipment the unit procedure is carried out (Reactor, Diafilter etc.) and the operating mode of the unit procedure (batch or continuous).
When modeling a continuous process (e.g., a wastewater treatment plant), you may think of a (continuous) unit procedure as simply a single unit operation: an aeration basin simply represents a basin that receives flow continuously, processes (reacts) continuously and outputs flow continuously. Since that operation is “on” all the time, a continuous unit procedure cannot share its equipment with any other unit procedure.
As mentioned above, each unit procedure is represented on the flowsheet by an icon. There will be one or more input streams attached to the unit procedure as well as one or more output streams leaving the unit procedure. Any one of the operations in the unit procedure list can access any of the input and/or output streams (provided its model permits it). However, a stream can only be used by an operation in a unit procedure only once. In other words, no two operations can share an input stream or an output stream. Every unit procedure must be assigned a main piece of equipment that hosts the procedure. However, as mentioned in the previous section, in the case of batch processes, several unit procedures can be assigned to use the same host equipment.
Under a unit procedure icon you can see three labels. The first displays the name of the unit procedure, the second the name of the equipment, and the third (displayed on a separate line) represents a short description of the unit procedure. Finally, the look of the procedure's icon (including its labels) is determined by its drawing style. The style of a procedure dictates features like the color of the icon, the type of fonts used for the labels, the appearance or not of each of the labels, etc.
We present the various types of unit procedures available in SuperPro Designer in groups that are based on the type of actions they are intended to represent. For each group member, there will be a short description of its purpose and of its hosting equipment resource type. In addition, a comprehensive list of available operations is presented and references to similar procedures are given.
The following procedures are available in SuperPro Designer:
(*) These procedures are not available in EnviroPro Designer.