Process Dynamics, Operations, and Control
Lesson 1: Processes and Systems
context and direction
Process control is an application area of chemical engineering - an
identifiable specialty for the ChE.
It combines chemical process
knowledge (how physics, chemistry, and biology work in operating
equipment) and an understanding of dynamic systems, a topic important to
many fields of engineering.
Thus study of process control allows
chemical engineers to span their own field, as well as form a useful
acquaintance with allied fields.
Practitioners of process control find their
skills useful in design, operation, and troubleshooting - major categories of
chemical engineering practice.
Process control, like any coherent topic, is an integrated body of
knowledge - it hangs together on a multidimensional framework, and
practitioners draw from many parts of the framework in doing their work.
Yet in learning, we must receive information in sequence - following a
path through multidimensional space.
It is like entering a large building
with unlighted rooms, holding a dim flashlight and clutching a vague map
that omits some of the stairways and passages.
How best to learn one’s
In these lessons we will attempt to move through a significant portion of
the structure - say, half a textbook - in about two weeks.
Then we will
repeat the journey several times, each time inspecting the rooms more
By this means we hope to gain, from the start, a sense of
doing an entire process control job, as well as approach each new topic in
the context of a familiar path.
the job we will do, over and over
We encounter a process, learn how it behaves, specify how we wish to
control it, choose appropriate equipment, and then explore the behavior
under control to see if we have improved things.
introducing a simple process
A large tank must be filled with liquid from a supply line.
stands at ground level to operate the feed valve.
Another stands on the
tank, gauging its level with a dipstick.
When the tank is near full, the stick
operator will instruct the other to start closing the valve.
cause spills, but underfilling will cause later process problems.
revised 2006 Jan 30