In industrial cooling water systems, copper and its alloys are widely used because of their superior heat transfer properties. These materials are susceptible to corrosion, which causes two basic problems. The first and most obvious is the failure of equipment with the resultant cost of replacement and plant downtime. The second is decreased plant efficiency due to loss of heat transfer—the result of heat exchanger fouling caused by the accumulation of corrosion products. Regardless of the type of corrosion, power plants must ensure that it occurs as little as possible. On the other hand, they can monitor substances and parameters that indicate corrosion, such as conductivity, pH value, or the presence of corroding anions and cations. On the other hand, power plants can make sure that added corrosion inhibitors are present in sufficient amounts to prevent equipment failures.

There are two primary concerns about corroded copper from the heat exchanger. First, from an environmental standpoint, soluble copper is toxic and needs to be properly controlled in any discharge stream. Second, soluble copper will plate out on mild steel surfaces and form galvanic corrosion sites that result in severe localized corrosion (also known as pitting) and premature failure of steel heat exchangers. Every cooling water system should include a method of monitoring corrosion inhibitors in the system.

Triazoles (e.g., tolyltriazole, benzotriazole, and 2-mercaptobenzothiazole) are commonly added in the mg/L range to protect copper and its alloys from corrosion by forming sparingly soluble layers on the surface of the metal. After triazole adsorption, copper-azole complexes are believed to precipitate at the liquid-solid interface, thus protecting the metal substrate from further dissolution. These complexes are prone to oxidation and also react with added microbiocides. As a result, the triazoles have to be replenished, which necessitates regular concentration determinations.

Corrosion chemistry monitoring helps to minimize loss of efficiency and protect the components coming in contact with steam and water against damage. Timely and effective monitoring of power plant water chemistry is critical for maintaining efficiency and safety. By using online analyzers, operators gain the information they need to accurately identify trends and address operational issues before costly problems arise.

• Inline eluent preparation ensures consistently stable baselines
• Protect valuable company assets (e.g. pipes, PWR, and turbines, which are prone to corrosion)
• Safe working environment and automated sampling
• High precision analyses for a wide spectrum of analytes with multiple types of detectors