Automation of Heat Exchanger System using DCS

Abstract

Heat exchangers are built for efficient transferring heat from one fluid to another. They have an extensive demand in areas such as petroleum, refineries, chemical plants, petrochemical plants, natural gas processing, refrigeration, power plants, air conditioning, space heating and process industry. Automation of Heat exchange can be done optimally using PID Block. Using PID function block the outlet fluid temperature can be maintained as desired. The automation of Shell and tube type heat exchanger using Distributed Control System (DCS) is represented in this research paper. Automation is done using PID block in DCS. The input to PID block is measured variable (temperature of Inlet water) and the set point is desired value of the Outlet water temperature. The manipulated variable is the steam flow rate. As per the changes in the process temperature and the settings of P action, I action and D action, the output of the PID block is calculated and the steam valve opening is varied to maintain the water temperature. The values for proportional gain, integration time and derivative time are adjusted to optimize process performance.

Keywords: Distributed Control System (DCS), heat exchanger, proportional mode, integral mode, derivative mode, PID (Proportional Integral Derivative) mode