Discrete Washing: Oper. Conds Tab

Variable Definitions, Ranges and Default Values

The following table shows a brief description of the variables appearing in this tab. The table also displays their default values and their generally acceptable range. Note that due to how the variables are used in the modeling equations, the range of acceptable values may be further reduced:

Variable	Default Value	Range

● Entering Entity Description The description of the discrete entities that are fed into the equipment unit.	<Entity Name Unknown>	Any Text
○ Exiting Entity Description The description of the discrete entities that are transferred out of the equipment unit.	<Discrete Entity>	Any Text
● Wash In Stream/Port Indicates the input port that is connected to the wash-in stream. If a stream is already present at the selected port, then the button next to the selection is active. Click on the button to bring up the attached stream’s simulation dialog in order to provide its composition.	<None>	Any Text
◙ Wash In Volumetric Flowrate (L/h) The volumetric flowrate of the wash-in material being transferred in.	0.0	Positive
◙ Wash In Volume per Entity (L) The volume of wash-in material per discrete entity being fed.	0.0	Positive
○ Removal % The percent mass of a component that is transferred to the wash-out stream.	0.0	[0,100]
● Operating Throughput per Unit (entities/h) The feed rate of discrete entities per equipment unit.	0.0	Positive
○ Ignore Product Stream Temperature Check this box to ignore the specification/calculation of the product stream temperature.	No	Yes/No
● Equilibrium Temperature (^oC) The temperature of the product stream at thermal equilibrium.	25.0	Positive
◙ Approach to Equilibrium (%) Factor that indicates how close to thermal equilibrium the mixture of the wash-in stream and washed material is.	0	Positive
◙ Product Stream Temperature (^oC) The temperature of the product stream.	25.0	Positive
○ Setup Time The amount of time (per cycle) spent before each operation is carried in preparation for the actual execution of the operation. It may involve actions like cleaning, vacuuming, setting up of equipment, etc. which the user opted not to model explicitly.	0.0	Positive
◙ Process Time The actual duration of the operation (per cycle). It can be either set by user or set by a master-slave relationship.	0.0	Positive
○ Ignore Labor? Check this box to ignore labor for this operation. This option is used only if the process time is set by a master-slave relationship.	Yes	Yes/No

Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output

Specification Choices / Comments

The following list describes the available specification choices in this tab; for more details on how these are implemented, see Discrete Washing: Modeling Calculations.

● Entity Description...
The description of the Entering Entity to the equipment is displayed. You may also specify a description for the Exiting Entity from the equipment that results from washing.

● Wash-In Port/Stream...
Here, the wash-in stream ID is displayed. The composition and amount of the wash-in stream can be viewed/edited by clicking on the button next to the stream ID.

● Wash-In Amount Specification Options...
There are three options available for the specification of the wash-in amount:

a) if you choose the option Available in Wash-In Stream, the wash-in amount is that specified in the respective dialog of the wash-in stream.

b) If you choose the option Volumetric Flowrate, you can specify the volumetric flow rate of the wash-in stream. Please note that the corresponding total flow rates displayed in the wash-in stream dialog will not be updated until mass and energy balances are solved.

c) If you choose the option Volume per Mass of Feed, you can specify the mass-specific volume of the wash-in stream with respect to the mass of the feed stream. Please note that the corresponding total flow rates displayed in the wash-in stream dialog will not be updated until mass and energy balances are solved.

● Component Removal to Wash Out Stream...
The component removal fractions of the feed stream to the wash-out stream are specified on a mass percent basis.

● Operating Throughput per Unit...
The operating mass throughput per unit is based on the mass flow rate of the feed stream.

● Product Stream Temperature Specification Options...
The product stream temperature is either calculated based on the specified percent approach to equilibrium factor or it is set directly by the user. In the first case, the calculated equilibrium temperature is also displayed upon solution of the mass and energy balances.

● Duration Options...
In Rating Mode, you can set the process time (and the setup time), allow the process time to be calculated (based on the throughput and the rated throughput of the units), or allow the duration to match exactly the duration of another operation either in the same procedure or in another procedure. In Design mode, you must either specify the process time (and the setup time) or allow the duration to match exactly the duration of another operation (either in the same procedure or in another procedure) in order for the program to calculate the required power (per step and per unit).

a) If you choose to match the duration of this operation with the duration of another operation,

b) You introduce a master-slave relationship between the two operations. The program will match the setup-time, the process time and the turnaround time of this compressing operation (the 'slave') with the corresponding times of the reference operation (the 'master' operation). For more on master-slave relationship, see The Scheduling Tab.