Page 36 - Analysis, Synthesis and Design of Chemical Processes, Third Edition

Equipment is represented symbolically by “icons” that identify specific unit operations. Although the

American Society of Mechanical Engineers (ASME) [2] publishes a set of symbols to use in preparing
flowsheets, it is not uncommon for companies to use in-house symbols. A comprehensive set of symbols
is also given by Austin [3]. Whatever set of symbols is used, there is seldom a problem in identifying the
operation represented by each icon. Figure 1.4 contains a list of the symbols used in process diagrams
presented in this text. This list covers more than 90% of those needed in fluid (gas or liquid) processes.

Figure 1.4 Symbols for Drawing Process Flow Diagrams

Figure 1.3 shows that each major piece of process equipment is identified by a number on the diagram. A
list of the equipment numbers along with a brief descriptive name for the equipment is printed along the
top of the diagram. The location of these equipment numbers and names roughly corresponds to the
horizontal location of the corresponding piece of equipment. The convention for formatting and identifying
the process equipment is given in Table 1.2.