Centrifugal compressors play an important role within the process industry. In some cases compressor capacity may determine the throughput of a plant. If a compressor is used for refrigeration then any variation in compressor operation may directly impact the temperature control in key unit operations such as flash vessels and exothermic reactors. Also, the compressor …
Tag Archive: temperature
Jun
20
Duty Cycle Control
As discussed in Chapter 11 of Control Loop Foundation – Batch and Continuous Processes, some field devices used in the process industryrequire that the control system provide a pulsed output interface. For example, in the plastics industry extruders are often used to process plastic pellets into various products. Plastic pellets are fed into the barrel …
Jan
10
PID Feedback Control
Many processes have measured and unmeasured disturbance inputs that can significantly impact the value of the controlled and constraint outputs. Process plants are often quite complex and it is not possible for the operating staff to safely and efficiently control the process manually during normal operation. The most common means of providing automatic feedback control …