Studying the Control of Absorption Column

 The absorption column is one of the essential separation processes in industrial operation, so the need arises to control absorption column by process simulation and also to analyze system by method called frequency response using MATLAB₈ .This work dealt with gas-liquid (air-water) absorption packed column which is analyzed by bode plot and frequency response to determine the stability of the system with or without Proportional Controller (P), Proportional Integral Controller (PI) or Proportional Integral Derivatives Controller (PID).The frequency response gives the transient response information, by defining such frequency response quantities as gain margin and phase margin. This work presents dynamic analysis of absorption column which is single input/single output (SISO) using feed back control (P, PI and PID) with the parameters of Cohen-Coon, Ziegler Nichols and Internal Model control and compares between them. Another method of analysis is using root locus method to check the stability of the system. The additional method is using bode plot in the methods: Cohen-Coon, Ziegler-Nichols and Internal Model Controllers to see the stability with or without controller. The goal of this work is to control the absorbed gas
(as controlled variable) by changing the flow rate of liquid as a manipulated variable.