Page 227 - Analysis, Synthesis and Design of Chemical Processes, Third Edition

To estimate the cost of operating labor, the average hourly wage of an operator is required. Chemical
plant operators are relatively highly paid, and data from the Bureau of Labor and Statistics [5] give the
hourly rate for miscellaneous plant and system operators in the Gulf Coast region at $26.48 in May 2006.
This corresponds to $52,900 for a 2000-hour year. The cost of labor depends considerably on the
location of the plant, and significant variations from the above figure may be expected. Historically, wage
levels for chemical plant operators have grown slightly faster than the other cost indexes for process plant
equipment given in Chapter 7. The Oil and Gas Journal and Engineering News Record provide
appropriate indices to correct labor costs for inflation, or reference [5] can be consulted. The estimation
of operating costs is illustrated in Example 8.2.

Example 8.2

Estimate the operating labor requirement and costs for the toluene hydrodealkylation facility shown in
Figures 1.3 and 1.5.

From the PFD in Figure 1.5, the number and type of equipment are determined.

Using Equation (8.4), an estimate of the number of operators required per shift is made. This information
is shown in Table E8.2.

Table E8.2 Results for the Estimation of Operating Labor Requirements for the Toluene
Hydrodealkylation Process Using the Equipment Module Approach

0.5
0.5
0.1
N = [6.29 + (0) + (0.23)(11)] = [8.82] = 2.97
OL
The number of operators required per shift = 2.97.

Operating Labor = (4.5)(2.97) = 13.4 (rounding up to the nearest integer yields 14 operators)

Labor Costs (2001) = 14 × $52,900 = $740,600/yr

8.3 Utility Costs