Inhibiting corrosion in closed loop water systems
Corrosion can affect closed loop heating, cooling and chilled water systems even though oxygen levels tend to be lower in such fixed volume water systems. However, it is more common in heating systems where higher, fluctuating temperatures can increase rates of corrosion.
Corrosion control is important as if left unchecked it can lead to the degradation of metallic components and increased fouling from corrosion by-products. This can lower flow rates, cause blockages, and reduce reliability and life-expectancy. It can also lower heat transfer efficiencies which increases energy costs.
A thorough understanding of system metallurgy is essential in the development of an effective corrosion control programme. Several different metals are commonly used in closed loop systems and care needs to be taken that any chemical water treatment products selected are compatible. This is especially true for systems that contain aluminium.
Chemical corrosion control can be achieved by incorporating specialist closed loop water treatment technologies including high performance corrosion inhibitors and oxygen scavengers in to the water treatment programme.
Controlling fouling & microbial slimes in closed circuits
Closed circuit water systems can become fouled from sources including suspended solids, corrosion by-products, scaling and the build-up of microbial slimes from pseudomonas bacteria, nitrifying and sulphate reducing bacteria.
The accumulation of such fouling in the form of sludge and suspended solids can cause blockages, reduce heat transfer efficiencies, and constrict flow rates. It can also cause localised corrosion and bioaccumulation.
Pseudomonas bacteria can cause significant microbial fouling issues in closed cooling and chilled water systems. As Pseudomonas bacteria proliferates throughout such closed circuit systems thick microbial slimes can build-up to contaminate the water, reduce cooling efficiencies and increase operating costs.
Successful treatment of closed loop water systems that operate below temperatures of around 80oC should incorporate a broad spectrum biocide to control the growth and build-up of bacteria and microbial slimes within the closed system.
Controlling scale formation
The formation of scale (sometimes called limescale) in closed circuits and closed loop systems tends to be less of an issue because of the fixed volumes of water involved. However, if there are regular water losses that require significant make-up volumes then treatment for scale formation may be required.
This is usually more of an issue with heating systems, especially those using hard water, as the increased system temperatures make the hardness salts more insoluble. The build-up of scale on internal surfaces can cause blockages, reduce heat transfer efficiencies, and constrict flow rates.
Closed systems water treatment training
The industrial and process water treatment specialists at Water Treatment Services have developed an extensive series of professional water and wastewater treatment training courses that includes WTS 0060 “Water Treatment for Closed System Heating & Cooling Water Circuits”. This specialist training for closed systems comprises an intensive one day course designed for facilities managers, water treatment service engineers, maintenance and engineering contractors, plant operators, and those with responsibility for the installation, pre-commissioning, maintenance and on-going management of commercial and industrial closed water systems used in heating, chilled and cooling water installations… water treatment training →
Expert closed loop water treatment solutions
Contact Water Treatment Services today to discuss your closed loop water treatment requirements. We can provide expert advice and engineering support regarding the management and water treatment of closed loop heating, cooling and closed circuit chilled water systems to help reduce costs, save energy, enhance operational efficiency and reliability, and extend asset lifecycles.
With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained engineers, in-field water management specialists and technical experts we can offer professional, cost effective water treatment and engineering services across the whole of the UK and Ireland.
Contact us today for more information or for your FREE, no obligation quote.