This dialog appears when selecting the Equipment Contents } Initial } Options menu option from a procedure’s command menu. It is only present if the procedure is hosted by an equipment resource whose type features a volume (e.g. vessel).
From this dialog you can specify how the application will initialize the contents of the particular equipment resource, right before the batch simulation calculations start and, therefore, right before the first use of the resource by a procedure. By default, the contents are initialized with the default fill-up ingredient which is “Air”. Specifically, the program will calculate how much of the default ingredient is needed in order to be consistent with the pressure specified by the user in the Initial Equipment Contents (View/Edit) Dialog.
It is possible to deviate from the default option for initializing the equipment contents by selecting one of the options 2 to 4. When option 2 is selected, the user has the alternative to either specify the composition percentages or the exact amounts of components which comprise the initial equipment contents. In the former case, the program will calculate the amount needed in order to satisfy the user-defined pressure. In the latter case, if the actual pressure of the user-defined initial contents is lower than the initial contents pressure specified in the Initial Equipment Contents (View/Edit) Dialog, an appropriate amount of the default fill-up ingredient will be added by the program to equalize the two pressures, provided the respective check-box is activated.
In some particular situations (e.g. when a holding tank retains material from a later step in the recipe but also uses its contents to feed an early step in the process as well) it may make sense to select the third option and initialize the equipment contents with whatever was calculated as the final contents in the previous simulation run.
Finally, the last option is more intriguing. It allows the contents of the equipment to be initialized by the contents of another equipment either in the same or in another process file. The latter option is particularly important in cases where a long process has been broken down to individual steps, each simulated in a separate file. For example, each file can capture the production of each intermediate needed to complete the formulation of a final product. In such cases, the user may end up leaving the final amount of an intermediate in vessel and dictate, by using the above option, to have the contents of the follow-up step to be filled up with the contents as left from the previous process. Please note that the same file-to-file link can also be done through output-to-input stream initialization (see Auto-Initialization of Input Streams).When selecting such a source for the initialization of the equipment contents, you must specify the name of the file and the name of the equipment resource to be used as the source for the material. Beyond that, you have the choice to either have the contents copied ‘as-is’ or to have the amount multiplied by a factor. This feature can be useful to capture a batch-to-batch ratio that may exist between an intermediate’s batch size and the follow-up step batch size. You can also have the choice of having just the composition carried over but not the amount or any of the other conditions (temperature, pressure). Similarly to option 2, when only the composition is carried over, the program will calculate amount needed in order to satisfy the user-defined pressure. On the other hand, in the case that the component amounts are set, if the actual pressure of the contents is lower than the specified initial contents pressure and the respective check-box is activated, an appropriate amount of the default fill-up ingredient will be added by the program to maintain pressure consistency.
Finally, when the source for the initial contents is a foreign object (as is in the case of another equipment resource), the user can dictate if it is needed for SuperPro Designer to fetch the initial contents from the source before each time the M&E balances are executed. Since it is presumed that the source’s contents don’t change between M&E simulations this may not be necessary. You can force the initialization manually by selecting Equipment Contents } Initial } Auto-Initialize from the command menu of any of the procedures hosted by the equipment.