Page 229 - Sustainability in the Process Industry Integration and Optimization

206 Cha p te r N i n e

from the complete flowsheet for the purpose of quick “what if”
analyses (Chempute Software, 2001).
Results output by the program include a full heat and material
balance; thermodynamic and physical properties of all streams;
component flow rates; stream temperatures, pressures, and vapor
fractions; and process equipment parameters. The user may view the
results graphically or obtain a printout of either summary or detailed
results. CHEMCAD includes additional modules; some of them are
(1) CHEMCAD-THERM for the design and rating of shell-and-tube
heat exchangers (including air coolers), (2) CHEMCAD-BATCH for
simulation of batch distillation processes, and (3) CHEMCAD-REACS
for the dynamic simulation of stirred tank reactors. The software
package also includes a subroutine, called CONVERT, which
translates the process flow diagram generated by the program into a
series of drawing exchange format (DXF) files for incorporation into
AutoCAD software routines.

9.5.5 PRO/II
The PRO/II computer simulation system is used by process engineers
in the chemical, petroleum, natural gas, solids processing, and
polymer industries (IPS, 2009b). It includes a large chemical component
library and multiple thermodynamic property prediction methods as
well as advanced and flexible techniques for evaluating unit
operations. The software tool can perform mass and energy balance
calculations for modeling steady-state processes. Expert systems,
extensive input processing, and error checking are included to help
inexperienced users. Typically, PRO/II simulation is applied to the
following tasks: (1) process design; (2) evaluating alternative plant
configurations; (3) modernizing and revamping existing plants;
(4) assessing, documenting, and complying with environmental
regulations; (5) troubleshooting and de-bottlenecking plant processes;
and (6) monitoring and improving plant yields and profitability.

9.6 General-Purpose Optimization Packages

9.6.1 GAMS
The General Algebraic Modeling System (GAMS, 2009) is a high-level
modeling system for Mathematical Programming and optimization.
GAMS is designed for modeling linear, nonlinear, and mixed integer
optimization problems. The system is well suited to complex, large-
scale modeling applications, and it allows the user to build and
archive large models that can later be adapted to new situations. A
particular advantage of GAMS is its ability to handle large, complex,
and/or unique designs that may require many revisions before an
accurate model is established.