Hello and welcome to this lecture on the main characteristics of block flow diagrams, process
flow diagrams, and piping and instrumentation diagrams.
My name is Marina Miletic.
this is an example of a block flow diagram, a BFD for short, for an ethylene oxide production
process.
Notice this is a very simple, bare-bones diagram of an entire process all on one page.
There is a lot of detail that is excluded from a diagram like this, but its usefulness
lies in its simplicity, because you can very quickly determine the most critical units
involved in the process.
This is an example of a process flow diagram, a PFD for short, again for the same ethylene
oxide production process.
Notice this diagram includes quite a bit more detail, more equipment, and more streams compared
to the block flow diagram.
This process flow diagram provides a great deal of information because it includes every
piece of equipment, and the whole process is shown again all on one page.
This is an example of a piping and instrumentation diagram, a P&ID for short, of that same ethylene
oxide process again.
This is just one of the distillation columns in the ethylene oxide process and no other
equipment is shown.
This is because there is an extraordinary level of detail shown on a piping & instrumentation
diagram, where every indicator, control loop, valve, and piping diameter are shown, among
other information.
Taken together, you can see that the block flow diagrams include the least amount of
detail, and the piping and instrumentation diagrams the most.