Page 202 - Plant design and economics for chemical engineers

176 PLANT DESIGN AND ECONOMICS FOR CHEMICAL ENGINEERS

TABLE 12
Typical variation in percent of fixed-capital investment
for yard improvements

Typical
Yard improvement Range, % value, %

Site clearing 0.4-1.2 0.8
Roads and walks 0.2-1.2 0.6
Railroads 0.3-0.9 0.6
Fences 0.1-0.3 0.2
Yard and fence lighting 0.1-0.3 0.2
Parking areas 0.1-0.3 0.2
Landscaping 0.1-0.2 0.1
Other improvements 0.2-0.6 0.3

an average for a normal solid-fluid processing plant. For a single-product, small,
continuous-process plant, the cost is likely to be in the lower part of the range.
For a large, new, multiprocess plant at a new location, the costs are apt to be
near the upper limit of the range. The cost of service facilities, in terms of
capital investment, generally ranges from 8 to 20 percent with 13 percent
considered as an average value. Table 13 lists the typical variations in percent-
ages of fixed-capital investment that can be encountered for various components
of service facilities. Except for entirely new facilities, it is unlikely that all
service facilities will be required in all process plants. This accounts to a large
degree for the wide variation range assigned to each component in Table 13.
The range also reflects the degree to which utilities which depend on heat
balance are used in the process. Service facilities largely are functions of plant
physical size and will be present to some degree in most plants. However, not
always will there be a need for each service-facility component. The omission of
these utilities would tend to increase the relative percentages of the other
service facilities actually used in the plant. Recognition of this fact, coupled with
a careful appraisal as to the extent that service facilities are used in the plant,
should result in selecting from Table 13 a reasonable cost ratio applicable to a
specific process design.

Land
The cost for land and the accompanying surveys and fees depends on the
location of the property and may vary by a cost factor per acre as high as thirty
to fifty between a rural district and a highly industrialized area. As a rough
average, land costs for industrial plants amount to 4 to 8 percent of the
purchased-equipment cost or 1 to 2 percent of the total capital investment.
Because the value of land usually does not decrease with time, this cost should
not be included in the fixed-capital investment when estimating certain annual
operating costs, such as depreciation.