Cooling water treatment

Cooling water treatment, at the crossroads of chemistry, biology and physics, has been profoundly modified over the last ten years by :

• Legionella treatment regulations and implementation protocol;

• REACH regulations and biocide directive no. 528/2012 of May 22, 2012;

• the obligation for manufacturers to optimize their water consumption;

• the development of membrane technology;

• the discovery of new scale and corrosion inhibitors;

• development of a monitoring system to track the operation of cooling circuits, treatments and their results.

The coming years will see the introduction of new regulations governing the discharge of products that are harmful to the environment. Corrosion inhibitors, scaling inhibitors and biocides are formulated with raw materials that have little or no toxicity for humans and the environment. Legislators have given priority to prior risk analysis, leading to preventive actions that avoid the continued use of hazardous chemicals. Analysis of the cause prevails over treatment of the consequences, based on routine effectiveness. The inhibition of biofilm formation based on the repulsion of bacteria for their supports is a subject of research which is likely to lead to industrial applications, particularly in seawater treatment.

The aim of this article is to provide the reader with the scientific basis and vocabulary needed to :

• Understand the causes of imbalances that are detrimental to the efficiency and long-term viability of cooling systems;

• be familiar with proposed solutions involving chemical products and engineering technologies;

• master a follow-up program ;

• to be a critical, mature partner for water treatment companies providing cooling water treatment services.

The treatment of surface or borehole make-up water will be discussed. Seawater treatment will also be studied, as this is a fundamental issue in the Middle East, North Africa and Spain for the chemical, steel and oil industries.

Cooling water treatment is part of a wider framework of energy management, water savings and wastewater treatment.

While the presence of the engineer in charge of monitoring installations will remain indispensable for some years to come, systems for monitoring installations and tracking results, whose reliability is improving, will take precedence over a quasi-permanent presence that is costly for...