This operation simulates a column regeneration step in flow-through and bind-and-elute chromatographies which is used to restore the column to its initial state. The main objective of this operation is to determine buffer consumption. By default, any change that may occur in the column’s retained mass during this step is ignored. Optionally, the entire column contents may be removed to the buffer outlet stream.
● Membrane Adsorption Procedure in Flow-Through Mode
● Membrane Adsorption Procedure in Bind-and-Elute Mode
You need to specify the values of two out of the following three variables: buffer flowrate, buffer volume, and process time time. The value of the remaining variable will be calculated by the model as explained below.
The process time can be either set by user or calculated based on the buffer volume and flowrate as follows:
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where ‘Feed Volume’ denotes the buffer volume in the context of this operation. If the process time is set by user then the above equation is used to calculate either the buffer flowrate (if the buffer volume is set) or the buffer volume (if the buffer flowrate is set).
If the process time is set and the buffer flowrate is set, or if the process time is calculated, you can specify any one of the following three variables: linear velocity, absolute flowrate, or relative flowrate. The other two variables will be calculated by the program according to the following equations:
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If the process time is set, the above two equations are used to calculate the linear velocity and relative flowrate, respectively.
If the process time is set and the buffer volume is set, or if the process time is calculated, then you can either set the absolute buffer volume (per batch cycle and equipment unit) or the relative buffer volume (in bed volumes). The buffer’s absolute volume is equal to its relative volume times the bed volume. This relation is used to determine the absolute volume based on a relative volume, and vice versa.
The user must specify the buffer’s inlet and outlet (waste) stream ports and the inlet stream’s composition. The program will auto-adjust the total flow of the inlet stream (and, thereby, the flows of individual components in it) based on the buffer’s volume per batch cycle and per equipment unit.
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As far as the inlet stream is concerned, you only need to specify a valid composition for that stream and not worry about total stream flow (since the flowrate of the buffer’s inlet stream will be auto-adjusted by the program). |
All components of the buffer’s inlet stream end up in the buffer’s outlet (waste) stream. If the option ‘Remove Column Contents’ is checked, then the entire column contents are removed from the column and added to the buffer’s outlet (waste) stream.
The interface of this operation has the following tabs:
● Oper. Cond’s, see Column Regeneration: Oper. Conds Tab
● Labor, etc, see Operations Dialog: Labor etc. Tab
● Description, see Operations Dialog: Description Tab
● Batch Sheet, see Operations Dialog: Batch Sheet Tab
● Scheduling, see Operations Dialog: Scheduling Tab
