Scaling process and its inhibition in industrial water systems

Scaling is characterized by the formation of encrusting, compact and adherent deposits on the surface of materials in contact with natural water. They can affect all sectors of activity, including agriculture, industry and drinking water distribution.

It's obvious that scale deposits can lead to major technical problems, such as partial or total blockage of pipes. But these phenomena also have considerable financial consequences, linked for example to cleaning, replacement of structures, loss of earnings due to production stoppages, energy losses... These unproductive costs are estimated at around 1.5 billion euros per year in France . In nuclear power plants, power output is often limited by scale deposits in the cooling towers .

The physical factors influencing scale formation when using natural water in circuits are mainly due to variations in temperature, pressure and mineral salt concentration.

Temperature increases occur in heat exchanger systems and water distribution pipes. The presence of scale on the walls of a heat exchanger leads to an increase in internal thermal resistance, which reduces not only its service life, but above all its efficiency. Indeed, considering that it mainly consists of calcium carbonate (CaCO ₃ ), scale is 15 to 30 times less conductive than steel .

As a result, it's vital to keep scaling under control. To achieve this, specific treatments exist, involving pre-treatments and conditioning products. However, these conventional products use fossil carbon from petrochemicals in their life cycle. In the long term, this resource is unsustainable. It is therefore essential to find more environmentally-friendly and cost-effective solutions to inhibit these phenomena.