Page 129 - Academic Press Encyclopedia of Physical Science and Technology 3rd Chemical Engineering

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Encyclopedia of Physical Science and Technology EN002G-100 May 19, 2001 18:49

Chemical Process Design,

Simulation, Optimization,

and Operation

B. Wayne Bequette Louis P. Russo
Rensselaer Polytechnic Institute ExxonMobil Chemical

I. Background
II. Process Models
III. Process Simulation
IV. Optimization
V. Process Design
VI. Design for Operability and Flexibility
VII. Process Operation

GLOSSARY equipment to minimize the annualized costs (including
operating costs and capital investment amortized over
Control Usingamanipulatedinputvariable(oftenavalve several years).
regulating a stream flowrate) to maintain a measured Process design The specification of process equipment
output variable (often temperature, level, pressure, or and flowstreams necessary to produce chemical pro-
composition) at a desired value (setpoint). cesses to meet desired production specifications.
Flowsheet A schematic representation of the chemical Process model A mathematical description of a chem-
process streams and unit operations involved in a chem- ical process that, if solved, enables prediction of the
ical process. behavior of the chemical process.
Operability The ability of a process to be regulated at Simulation The numerical solution of a mathematical
desired operating conditions under uncertainty in feed model, often refers to the numerical solution of a model
or utility streams. of an entire process flowsheet.
Optimization Mathematical procedures to enable the Unit operation Typically, an equipment item that per-
best selection from a set of many options, for exam- forms a chemical/physical transformation of a process
ple, in the context of process design, the selection of stream, for example, a heat exchanger may increase the

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