Page 116 - Plant design and economics for chemical engineers

92 PLANT DESIGN AND ECONOMICS FOR CHEMICAL ENGINEERS

The factors that must be evaluated in a plant-location study indicate the
need for a vast amount of information, both quantitative (statistical) and
qualitative. Fortunately, a large number of agencies, public and private, publish
useful information of this type greatly reducing the actual original gathering of
the data.

Raw materials availability. The source of raw materials is one of the most
important factors influencing the selection of a plant site. This is particularly
true if large volumes of raw materials are consumed, because location near the
raw-materials source permits considerable reduction in transportation and stor-
age charges. Attention should be given to the purchased price of the raw
materials, distance from the source of supply, freight or transportation ex-
penses, availability and reliability of supply, purity of the raw materials, and
storage requirements.

Markets. The location of markets or intermediate distribution centers affects
the cost of product distribution and the time required for shipping. Proximity to
the major markets is an important consideration in the selection of a plant site,
because the buyer usually finds it advantageous to purchase from nearby
sources. It should be noted that markets are needed for by-products as well as
for major final products.

Energy availability. Power and steam requirements are high in most industrial
plants, and fuel is ordinarily required to supply these utilities. Consequently,
power and fuel can be combined as one major factor in the choice of a plant
site. Electrolytic processes require a cheap source of electricity, and plants using
electrolytic processes are often located near large hydroelectric installations. If
the plant requires large quantities of coal or oil, location near a source of fuel
supply may be essential for economic operation. The local cost of power can
help determine whether power should be purchased or self-generated.

Climate. If the plant is located in a cold climate, costs may be increased by the
necessity for construction of protective shelters around the process equipment,
and special cooling towers or air-conditioning equipment may be required if the
prevailing temperatures are high. Excessive humidity or extremes of hot or cold
weather can have a serious effect on the economic operation of a plant, and
these factors should be examined when selecting a plant site.

Transportation facilities. Water, railroads, and highways are the common means
of transportation used by major industrial concerns. The kind and amount of
products and raw materials determine the most suitable type of transportation
facilities. In any case, careful attention should be given to local freight rates and
existing railroad lines. The proximity to railroad centers and the possibility of
canal, river, lake, or ocean transport must be considered: Motor trucking