 |  Plant Design and Economics for Chemical Engineers, 5/e Max S. Peters,
University of Colorado
Klaus Timmerhaus,
University of Colorado, Boulder
Ronald E. West,
University of Colorado, Boulder
Heat-Transfer Equipment - Design and Costs
Chapter OverviewM
odern heat-transfer equipment includes not only simple concentric-pipe
exchangers but encompasses complex surface exchangers with thousands of
square meters of heating area. Between these two extremes are the conventional
shell-and-tube exchangers, coil heaters, bayonet heaters, extended-surface
finned exchangers, plate exchangers, condensers, evaporators, furnaces, and many
other, more specialized heat-transfer units. Intelligent selection of heat-transfer equipment
requires an understanding of the basic theories of heat transfer that are incorporated
in the sophisticated computer programs presently being used to perform the
required design calculations. This chapter presents an outline of heat-transfer theory
and the associated design calculation methods, together with an analysis of the general
factors that must be considered in the selection of heat-transfer equipment.
The shell-and-tube exchanger is the most commonly used type of heat exchanger
in the process industry, accounting for at least 60 percent of all heat exchangers in use
today. Figure 14-1 shows design details of a conventional two-pass exchanger of the
shell-and-tube type. Such exchangers are designed according to TEMA (Tubular Exchanger
Manufacturers Association) specifications and are available for virtually any
capacity and operating condition, from high vacuums to ultrahigh pressures, from very
low to very high temperatures, and for many temperature and pressure differences between
the fluids being heated and cooled. Materials of construction generally provide
the only limitations on the operating conditions since they can be designed to meet
other conditions of vibration, heavy fouling, highly viscous fluids, erosion, corrosion,
toxicity, multicomponent mixtures, etc. Shell-and-tube exchangers may be fabricated
from a variety of metal and nonmetal materials with surface areas available from 0.1
to 100,000 m2 . However these heat exchangers generally exhibit an order of magnitude
less surface area per unit volume than compact heat exchangers and require considerable
space, weight, and support structure.
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2003 McGraw-Hill Higher Education