pH Regulation (Cont): 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:

Variable	Default Value	Range

○ Output pH The pH of the mixture.	7.0
○ Initial Guess Set by User Check this box to provide an initial guess for the add-in stream flow.	No	Yes/No
◙ Initial Guess The initial guess for the add-in stream flow.	0.0	Positive
◙ Final Temperature (^oC) The final temperature of vessel contents after the end of the operation.	25.0	Positive
◙ Heating Duty (kcal/h) The heat transfer rate of the heating agent, if a heating agent is used.	0.0	Positive
◙ Cooling Duty (kcal/h) The heat transfer rate of the cooling agent, if a cooling agent is used.	0.0	Positive
○ Heat Transfer Agent Name Indicates the heat transfer agent used for the operation. Click on the list box to bring up a list of available heat transfer agents in order to select one.	<Chilled Water>	Any Heat Transfer Agent
● Inlet Temp. (^oC) The inlet temperature of the heat transfer agent.	5.0	Positive
● Outlet Temp. (^oC) The outlet temperature of the heat transfer agent.	10.0	Positive
● Rate (kg/h) The mass flow rate of the heat transfer agent.	0.0	Positive
○ Power Type Indicates the power type that is used by the operation. Click on the list box to bring up a list of available power types in order to select one.	<Std Power>	Any Power Type
◙ Specific Power (Per Volume) (kW/m³) The power consumed for agitation per volume of material.	0.1	Positive
◙ Total Power (kW) The total power consumed for agitation (per cycle).	0.0	Positive
◙ Power Per Unit (kW) The power consumed for agitation per equipment unit.	0.0	Positive
○ Power Dissipation to Heat (%) The percentage of total power consumed for this operation that turns into heat, thereby raising the temperature of the material contained in the equipment.	100.0	[0,100]
○ Pressure Set by User Check this box to set the pressure.	No	Yes/No
◙ Pressure (atm) The operating pressure of the equipment.	1.0	Positive
○ Allow for a Split After Reaction Check this box to enable split after reaction.	No	Yes/No
○ Gaseous Components Available to React Check this box to consider gaseous components in reactions.	Yes	Yes/No
● Operating Throughput per Unit (kg/h) The mass flow rate of the mixture in the equipment.	0.0	Positive

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

Specification Choices / Comments

•Component pH Data.

In order to calculate a meaningful value for the pH of stream the use has to provide the pH data of its components from the Pure Component: pH Data tab of the component registration dialog.

•Operating Throughput per Unit...

The operating throughput per unit is based on the mass flowrate of the output stream.

•Time Reference...

Choose the time reference for flowrate. The flowrate can be specified by the user to be per Batch, per Cycle, or per Time Average. Depending on whether the procedure is in batch mode or continuous, and the whether process is in batch mode or continuous, certain options may not be available. Specifically the availability of time reference flows depending on the mode of procedure / process is:

Process Mode	Procedure Mode	Time Reference for Flow

Batch	Batch	Batch / Cycle
Batch	Continuous	Batch / Time Average
Continuous	Continuous	Time Average
Continuous	Batch	Cycle / Time Average

•Duration Options...

The duration controls appear only if the procedure is in batch mode. In Rating Mode, you can set the process time (and the setup time), allow the process time to be calculated (based on the 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).

If you choose to match the duration of this operation with the duration of another operation, 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 operation (the ‘slave’) with the corresponding times of the reference operation (the ‘master’ operation). For more on master-slave relationship, see The Scheduling Tab.