Water is an increasingly valuable resource. On average, 44 % of total water abstraction in Europe is used for agriculture, 40 % for industry and energy production, and 15 % for public water supply.

Typical examples of use in industry, are the cooling towers used in heavy manufacturing plants and those used for electrical power generation. Among the largest users of water per unit cost of products manufactured are the steel, chemical and pulp and paper industries.

Industrial water consumption is a significant factor in production costs and has become important as part of the efforts to conserve water resources. In the past, much of the water used in industrial applications was lost into the atmosphere as steam. Today, the majority of industrial water is captured and continuously recycled in a closed loop for more efficiency and with respect to the Waste Hierarchy and the Circular Economy approaches that are championed in the EU in particular. However, this brings new challenges as the water can easily become infested with unwanted and harmful microorganisms. These microbes need to be eliminated using biocides to avoid biologically induced corrosion, scale deposits and slime formation.