Instrumentation and Control System

The type of control system and instrumentation to be selected will depend on its location (e.g., the danger of fire, explosion, pollution, moisture, the conditions of temperature and its variations). The control equipment can be classified as... 

When using the operability study technique to vet a process design, the action to be taken to deal with a potential hazard will often be modifications to the control systems and instrumentation the inclusion of additional alarms, trips, or interlocks. If major hazards... 

Improved stability. When columns operate close to their capacity limits, even small disturbances can carry the column beyond the flood point (152). Once flooding sets in, it may be difficult to return the column to normal operation unless vapor and liquid traffic are largely reduced. In order to operate the column at a point close to maximum capacity, stable operation and reduction of the magnitude and frequency of outside disturbances are essential. The column control system and instrument tuning play a major role in achieving maximum column capacity. It has been the author s experience that the improved stability can usually enhance capacity by 2 to 5 percent, and sometimes by up to 10 percent. 

Furnace system—typically used to heat up large quantities of hydrocarbons or chemicals. The basic equipment in a furnace system includes a furnace, advanced process control systems and instruments, pump systems, compressor systems, and fuel systems. 

Steam-generation system—a complex arrangement of boiler systems designed to convert water to steam. These include pump-around systems, advanced process control systems and instruments, fuel systems, and compressor systems. 

Process control systems and instrumentation can be described in several ways. Flowsheets show the process equipment, instruments, and control systems, as well as interconnections, such as piping and electrical and pneumatic transmission lines. More detailed flowsheets are referred to as piping and instrumentation diagrams (P IDs), They include additional information, such as valve characteristics, piping details (e.g., pipe sizes and fittings), and miscellaneous information, such as drains, vents, and samphng fines. Both types of diagrams are widely used in the process industries. 

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