Page 63 - 2024-Vol20-Issue2

Received: 22 July 2023 | Revised: 10 October 2023 | Accepted: 29 October 2023

DOI: 10.37917/ijeee.20.2.5 Vol. 20 | Issue 2 | December 2024

Open Access

Iraqi Journal for Electrical and Electronic Engineering

Original Article

Design and Implementation of PID Controller for the

Cooling Tower’s pH Regulation Based on Particle Swarm

Optimization PSO Algorithm

Basim Al-Najari*1, Chong Kok Hen1, Johnny Koh Siaw Paw1, Ali Fadhil Marhoon2
1Department of Electrical & Electronics Engineering, University of Tenaga UNITEN, Selangor, Malaysia

2Department of Electrical Engineering, University of Basrah, Al-Basrah, Iraq

Correspondance
*Basim Mohsin Abdulwahid Al-Najari
Al-Basrah, Iraq
Email: pe21023@student.uniten.edu.my

Abstract
The PH regulation of cooling tower plant in southern fertilizers company (SCF) in Iraq is important for industry pipes
protection and process continuity. According to the Mitsubishi standard, the PH of cooling water must be around (7.1
to 7.8). The deviation in PH parameter affects the pipes, such as corrosion and scale. Acidic water causes pipes to
corrode, and alkaline water causes pipes to scale. The sulfuric acid solution is used for PH neutralization. The problem
is that the sulfuric acid is pumped manually in the cooling tower plant every two or three hours for PH regulation. The
manual operation of the sulfuric acid pump makes deviations in the PH parameter. It is very difficult to control the PH
manually. To solve this problem, a PID controller for PH regulation was used. The reason for using the PID controller
is that the PH response is irregular through the neutralization process. The methodology is to calculate the transfer
function of the PH loop using the system identification toolbox of MATLAB, to design and implement a PID controller,
to optimize the PID controller response using particle swarm optimization PSO algorithm, and to make a comparison
among several tuning methods such as Ziegler Nichols (ZN) tuning method, MATLAB tuner method, and PSO algorithm
tuning method. The results showed that the PSO-based PID controller tuning gives a better overshoot, less rise time, and
an endurable settling time than the other tuning methods. Hence, the PH response became according to the target range.
The experimental results showed that the PH regulation improved using the PSO-based PID controller tuning.

Keywords
PH Regulation, PSO Algorithm, PID Controller, Cooling Tower, MATLAB, System Identification.

I. INTRODUCTION ment because it can swiftly degrade metals through oxidation
and reduction of chemical and electrochemical processes [3].
Cooling towers are heat rejection devices used to transfer The emergence of corrosion, moss, and crustal precipitation
waste heat to the atmosphere through the cooling of a water can inhibit heat transfer so that it can disrupt the level of
stream [1]. Cooling towers are used to increase productivity thermal effectiveness of the cooling tower. Not only does it re-
and efficiency in industrial machinery. The formation of Cor- duce thermal effectiveness, but it can also damage the cooling
rosion and humid grass inhibits the heat transfer system thus tower [4]. When water vaporizes from the cooling tower, these
affecting the efficiency level of the cooling tower. Without solids remain; causing the cooling water body to become more
proper water treatment, corrosion and scaling occurs in the concentrated which may then produce scale deposition heat
pipes and basin which results in poor heat transfer and ren- transfer surfaces. The hardness and silica ions are the knotty
ders the cooling tower inefficient [2]. Corrosion is one of the scale forming species in cooling tower water [5]. So, the PH
most severe threats in today’s industrial and marine environ-

This is an open-access article under the terms of the Creative Commons Attribution License,
which permits use, distribution, and reproduction in any medium, provided the original work is properly cited.
©2024 The Authors.
Published by Iraqi Journal for Electrical and Electronic Engineering | College of Engineering, University of Basrah.

https://doi.org/10.37917/ijeee.20.2.5 |https://www.ijeee.edu.iq 59