The Importance of Cooling Water Treatment System at Lumut Balai Geothermal Power Plant

Abstract

Cooling tower (CT) water treatment is very important to minimize the growth of microorganisms, minimize the formation of scaling, minimize corrosion and minimize sediment or solids deposition on the contact area of ​​heat transfer on the surface. The problem that often occurs in cooling water systems with open circulation is the growth of microorganisms. Microorganisms are living bodies that have a very small size (usually less than 1 mm) so that various auxiliary tools are needed to observe them. Some of the factors that can cause the growth of microorganisms are food substances for microorganisms, water temperature, degree of acidity, dissolved oxygen, sunlight, the number of bacteria, turbidity, the volume of moss, level of moss attachment, water flow rate, and others. Treatment of algae and microorganism existences in cooling water can be controlled by using microorganism control agents. The control material is divided into two, namely by using Oxidizing Biocide inhibitors and Non-Oxidizing Biocide Inhibitor. The difference between both of them, in general, is that the oxidizing biocide inhibitor works directly by killing microorganisms. Meanwhile, non-oxidizing biocide inhibitors play a role by suppressing the growth of these microorganisms. On the other hand, the impact of this chemical is foaming appearance in CT basin resulting in a decrease in the vacuum condenser. When there is a decrease in the vacuum condenser, steam consumption will increase, and if the available steam supply is insufficient, in other words, the generation load will decrease. Eventually, the usage of non-surfactant and oxidizing biocide are used to prevent the foaming and microorganism itself.