BATCHFRAC Distill Specification

Specify the actual distillation in a BATCHFRAC unit. Distill is the only action that advances the simulated time. Distill actions is optional for the first segment and is required for all other segments of the Overall Operating Policy table on the BATCHFRAC Main Window. Only one Distill action is allowed in each policy segment.

Usage

Each Distill action continues until stopped by a Run Until Condition or a global maximum time per policy criteria.

Following specifications may be supplied based on the policy type:

Policy Type Specifications to be supplied

Standard Distillate specification only

Total Reflux Total Vapor Boil-up Rate specification only

Both Both Total Vapor Boil-up Rate and Distillate specifications

Total Vapor Boil-up Specification

The Total Vapor Boil-up Rate is the primary setting for column loading. It directly affects boilup, stillpot heat duty and condenser duty.

The Total Boilup Specification has to be supplied for the Distill action of each policy segment to reach total reflux condition. If boilup rate is not specified, then 10% of the initial charge per hour will be used for total reflux calculation.

A special case applicable to only the first policy is that the Distill action uses the optional values given for the Total Boilup Specification to reach the total reflux condition.

The values specified for one Distill action are used by the subsequent Distill policy segments.

Distillate Specification

Two Distillate Specifications may be supplied from the following options: Molar Reflux Ratio, Distillate Rate, Boilup Rate, Condenser Duty and Reboiler Duty. The valid combinations are:

1st Specification Options for the 2nd specification

Molar Reflux Ratio Distillate Rate / Boilup Rate / Condenser Duty / Reboiler Duty

Distillate Rate Molar Reflux Ratio / Boilup Rate / Condenser Duty / Reboiler Duty

Boilup Rate Molar Reflux Ratio / Distillate Rate

Condenser Duty Molar Reflux Ratio / Distillate Rate

Reboiler Duty Molar Reflux Ratio / Distillate Rate

To change the dimensional units displayed for entries, press the UOM button to view and use the Unit of Measure Selection Window.

For the Distill spec of the first policy the "Total Reflux" specification is defaulted to 10% of the initial charge per hour.
Only one DISTIL specification allowed for per policy.
For any Total Reflux type policy, only Boil-up Specs will be enabled.
For standard type policy, only distillate specifications enabled
For policy type=Both, all are enabled.
The following table details the valid pairs of Distillate Specifications:

	D	RR	BR	QC	QR
D		X	X	X	X
RR	X		X	X	X
BR	X	X
QC	X	X
QR	X	X

Distillate Rate (D)
Reflux Ratio (RR)
Condenser Duty (QC)
Reboiler Duty (QR)
Boilup Rate (BR)

How to get to this window

The BATCHFRAC - Distill Specification window is accessed by selecting Distill in the Action/Condition table in the BATCHFRAC - Policy Segment window and then clicking on the linked text under Description.

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