What is Azole used for in water treatment?
Azoles are used in water treatment because it is a structured ring-shaped organic molecule that acts as a corrosion inhibitor for copper and copper alloys in cooling water management schemes.
If you're involved in cooling towers or water treatment, you've probably heard of azoles.
Copper alloys are used in cooling systems because of their ability to transfer heat efficiently, so azoles are used to protect these alloys from potential corrosion.
However, there are drawbacks. Water treatment systems use halogens such as chlorine, fluorine, and bromine to treat the growth of microorganisms such as Legionella. This problem occurs when mixing azoles and halogens. Eventually, the protection provided by Azoles will no longer work. Systems that use tritriazoles, benzotriazoles, etc. are most affected by this problem. This allows plant operators to increase supply speeds, increasing not only cost but also damage to the entire system.
How do corrosion inhibitors work?
Corrosion inhibitors are chemicals that are added to the corrosion system to reduce the overall rate of corrosion without changing the concentration of the corrosive. Depending on the type of corrosion being treated, it can be cathode, anode, or film-forming and oxygen-absorbing. They are specially tuned to prevent things like calcification when used at low water concentrations. Corrosion inhibitors are multifunctional tailored to the cooling system to prevent and eliminate deposits in the water supply system.
The most common corrosion inhibitor
The most commonly used chemicals in wastewater treatment are benzotriazole (BTA) and tritriazole (TTA). Benzotriazole is especially used to protect copper because it is insoluble in aqueous and organic solutions. Tritriazole is another yellow metal corrosion inhibitor similar to benzotriazole and is used in industrial applications for systems where fluids constantly flow against corrosive metals.
It provides a thin hydrophobic film on top of the metal to protect them. These products worked well in the treatment of sewer systems before oxidative biocides became widespread.
But that's the problem.
In wastewater treatment, water is treated with an oxidative biocide to prevent microorganisms. Legionalla is a common concern in today's wastewater treatment world. As a result, biocides such as chlorine penetrate the hydrophobic membrane and fail to control corrosion.
Why test azoles in cooling water?
It is important to test azoles in cooling water systems as corrosion control failures are becoming an increasingly prevalent problem. Many systems were not designed with the use of oxidative biocides in mind. This issue was caused by a problem that is often overlooked.
As the azoles level goes down, the first instinct is to add more and more. Increasing the feed rate exacerbates the problem. By adding tritriazole to the system, chlorine continues to eat it up, eventually increasing the rate of corrosion of the copper alloy, even with more inhibitors used. This is why it is so important to have a dedicated water treatment plan to monitor azoles. Not only does it save chemicals, it also helps prevent damage to the wastewater treatment system.
Our Netsol Advantage
Netsol is a goto partner for wastewater treatment management. Our team not only provides the best products for the wastewater pre-treatment process, but also has the expertise to ensure that you have the right solution for your unique needs. We offer unique products to combat the deterioration of corrosion inhibitors and maintain azoles levels.