Streams with Defined Composition
This window is used to specify the stream data by specifying its rate and composition. The stream phase can be liquid, vapor, or a mixture of liquid and vapor.
Usage
This window is opened by selecting the Composition Defined option and then pushing the Flowrate and Composition button on the Stream Data Window.
Select a fluid flowrate specification and enter the appropriate values for stream composition/component flowrates.
Fluid Flowrate Specification
This specification can be either the Total Fluid Flowrate or the Individual Component Flowrates. If you select the Total Fluid Flowrate, enter its value in the data entry field.
If the total fluid rate is in liquid volume or vapor volume, Total LV or GV rate Basis list box will be enabled with two options Standard Basis and Adjusted Standard Basis. Default selection is with Standard Basis for LV or GV rate basis.
For more details on adjusted standard conditions, Refer PRO/II Reference help, Volume 3 Technical Bulletin, Chapter 1.
Component Table
The Component column of the table contains all the components currently defined in the flowsheet. You are required to enter values (composition or flowrates) only for those components which are present in the stream. All other components will be considered to be non-existent in the stream.
Depending upon the choice made for the Fluid Flowrate Specification, you should enter appropriate values for individual stream components. The various possibilities are:
If Total Fluid Flowrate has been selected
Enter the individual composition values for all the components that make
up the stream. The basis by which the compositions are entered can be
changed through the Convert
Unit of Measure Window which is displayed when the UOM
button on the Toolbar is pushed. The
default basis is "mole".
The individual compositions
must add up to 1.00, 100.0, or the total flowrate, within a tolerance
of 1%. If this tolerance is not met, an error message will be generated
when the OK button is pushed. Selecting the "Normalize" option
scales the individual compositions and avoids this error .
If Individual Component Flowrates has been selected
Enter the individual flowrate values for all the components that make up the stream. There is no restrictions on the flowrate sum for this option.
If Component concentration has been selected
Enter the individual Molar/Mass solute concentration values and solvent flow rates for all the components that make up the stream.
Total Flow is optional, if total flow is supplied, enter the solvent composition data. If total flow is not supplied, enter the solvent flow rate data.
Enter at least one Solvent composition/flow.
The following basis is considered for
Total Flow rate in Mass/Mole/LV/GV
Solvent Rate in Mass/Mole/LV/GV
Solute Concentration in Mass/Mole
Solvent composition is applicable to ”r;total flow rate minus solute flow rate” and not to total flow. This flow rate is normalized among the solvent components.
Adjusted standard basis and Normalized options are by default ON and disabled.
Clear Compositions
Press this button to remove all composition or component flowrate data entered into the table.
Normalize flowrate
If the total fluid flowrate has been entered, you may select the option of normalizing the composition of the individual components to the Total Fluid Flowrate. Since the composition values are normalized, no error condition arises when the required tolerances are not met.
Note: Normalization is performed during calculations to solve and converge the flowsheet. It is not peformed during input data processing.
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