Page 65 - Plant design and economics for chemical engineers

CHAPTER
3

GENERAL
DESIGN

CONSIDERATIONS

The development of a complete plant design involves consideration of many
different topics. Quite understandably, the overall economic picture generally
. dictates whether or not the proposed facility will receive management approval.
However, the application of engineering principles in the design of such a
facility in a safe and environmentally acceptable fashion, along with some
general design considerations, will ultimately determine whether these earlier
economic goals can be met.
Before proceeding any further with the development of a process design
and its associated economics, it will be desirable to consider an overall view of
the various functions involved in a complete plant design. Particular emphasis in
this discussion will be placed on important health, safety, loss prevention, and
environmental considerations. Other items that will be noted briefly include
plant location, plant layout, plant operation and control, utilities, structural
design, storage, materials handling, patents, and legal restrictions.

HEALTH AND SAFETY HAZARDS
The potential health hazard to an individual by a material used in any chemical
process is a function of the inherent toxicity of the material and the frequency
and duration of exposure. It is common practice to distinguish between the
short-term and long-term effects of a materiaf. A highly toxic material that’
causes immediate injury is classified as a safety hazard while a material whose