This document discusses adding a MASSBAL sub-flowsheet in HYSYS. It describes entering material streams and unit operations from a MASSBAL case file into HYSYS to generate simulation results. The MASSBAL file uses a graphical interface to define streams, units, and case specifications in a text file that HYSYS then translates and simulates. Key differences between HYSYS and MASSBAL stream definitions and naming conventions are also outlined. The document concludes by noting configuration options available on the Parameters tab for the MASSBAL solving process.

1. 2-18 Adding a MASSBAL Sub-Flowsheet
2-18
3. Click the Sub-Flowsheet Environment button to enter the
MASSBAL flowsheet environment.
A MASSBAL Object in HYSYS is a flowsheet object (similar to a template
object) that holds all streams or unit operations subject to the equation
based solver.
4. Enter the material streams and unit operations in the MASSBAL PFD
to create the simulation case.
The stand alone MASSBAL application uses a graphical interface to
create a *.dat file. The .dat file is a text file containing the streams,
unit operations, connections, and any specifications the case may
have. The *.dat file is used by HYSYS to generate simulation results.
HYSYS is able to translate the following unit operations: Separator,
Heat Exchanger, Valve, Heater, Cooler, Compressor, Expander,
Pump, Mixer, Tee, Recycle, Adjust, and Set.
The concept of the stream in HYSYS is different from that in
MASSBAL. HYSYS streams are flowsheet objects with properties/
characteristics (and can exist without unit operations) whereas
MASSBAL streams are connections between unit operations. Special
streams known as Sources feed into unit operations and are fully
defined for VLE cases. Streams that exit the flowsheet are known as
Sinks.
In MASSBAL, convention dictates that streams are defined as either
feeds to a unit operation, or products of a unit operation. In
generating identifiers for streams, HYSYS has associated each
stream as the product of the immediate upstream unit operation.
This works for all streams except Source streams which, by
definition, are fully defined.
5. On the Parameters tab:
• Select the option for the convergence process.
• Enter specifications used for the MASSBAL equation-based
solver.
• Manipulate the solving behaviour of the MASSBAL flowsheet.
Refer to Chapter 8 - HYSYS
Objects in the User Guide
for more information
regarding installing streams
and operations.
Refer to Section 2.5.2 -
Parameters Tab for more
information.