Page 209 - Analysis, Synthesis and Design of Chemical Processes, Third Edition

following sources: Peters and Timmerhaus [2], Guthrie [9, 10], Ulrich [5], Navarrete [11], and Perry et
al. [3]. Example 7.12 illustrates the use of these figures and tables.

Example 7.12

Find the bare module cost of a floating-head shell-and-tube heat exchanger with a heat transfer area of
2
100 m for the following cases.
a. The operating pressure of the equipment is 1 barg on both shell and tube sides, and the MOC of
the shell and tubes is stainless steel.
b. The operating pressure of the equipment is 100 barg on both shell and tube sides, and the MOC
of the shell and tubes is stainless steel.

From Example 7.10, (2001) = $25,000 and (2006) = $25,000 (500/397) = $31,490.
a. From Example 7.10, at 1 barg, F = 1
P
From Table A.3 for a shell-and-tube heat exchanger made of SS, Identification No. = 5 and using
Figure A.8, F = 2.73
M
From Equation A.4,

C BM (2006) = [B + B F F ] = $31,490[1.63 + 1.66(1.0)(2.73)] = $194,000
1
2 P M
b. From Example 7.11 for P = 100 barg, F = 1.383
P
From (a) above, F = 2.73
M
Substituting these values in to Equation A.4,

C (2006) = [B + B F F ] = $31,490[1.63 + 1.66(1.383)(2.73)] = $248,600
BM 1 2 P M

The last three examples all considered the same size heat exchanger made with different materials of
construction and operating pressure. The results are summarized below.

These results reemphasize the point that the cost of the equipment is strongly dependent on the materials of
construction and the pressure of operation.

7.3.5 Combination of Pressure and MOC Information to Give the Bare Module Factor, F BM , and
Bare Module Cost, C
BM

In Examples 7.10–7.12, the bare module factors and costs were calculated using Equation A.4. The form
of this equation is not obvious, and its derivation is based on the approach used by Ulrich [5]:

(7.11)