Water is omnipresent on Earth where it appeared three billion years ago. It covers approximately 71% of the globe and reaches a volume of 1350 billion m3. However, of this volume, only 0.7% represents available fresh water. It is the only substance to exist in its three states: solid, liquid and vapour.
The water molecule has amazing properties:
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its solid form is lighter than its liquid form, so ice floats;
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it has enormous surface tension which allows it to get wet and fit everywhere;
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it has a significant heat of vaporization, hence its ability to store large quantities of heat, the oceans thus playing a role in stabilizing the Earth’s temperature;
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it is a powerful polar solvent storing sodium chloride and carbon dioxide. The role of the oceans, capable of storing enormous quantities of greenhouse gases, is therefore essential in the current climate change.
Water vapor is a greenhouse gas but its properties (solvent power) and thermal properties (heat of vaporization and condensation) make it an essential thermal regulator for life on Earth.
Water is a source of life but is today a threatened asset. Currently, in the world more than 2 billion humans do not have quality water.
Its pollution, essentially of anthropogenic origin, is a major problem for humanity. Thus, the seas and oceans have become the receptacle of all the rejections of our consumer society. The “Gyres”, these “continents” which drift according to the ocean currents made up of plastic residues (tyres, particles from washing machines, etc.), are perhaps among the most distressing sights possible to observe. Groundwater is not spared either with pollution and overexploitation that exceed their capacity for renewal.
Due to its unequal distribution in the world and the effects of climate change which accentuate episodes of water stress, water also takes on a geopolitical importance which is still growing with the increase in the world’s population. Access to water will represent a growing source of border conflicts in the years to come.
Having an abundance of quality water at the tap is a wealth that the user does not generally measure.
From an economic point of view, water also plays an essential role in many uses including agriculture for irrigation, industry and domestic uses.
To be used, water must be collected, often treated and distributed. It must be constantly analyzed and monitored to meet the characteristics necessary for each of its uses. Water treatment uses the most varied technologies, which have evolved considerably in recent decades, particularly with regard to the desalination of seawater and brackish water (biological techniques, membranes, distillation, etc.). .
Technologies have also been developed to treat water in industry, the different uses of water requiring water of different qualities (pharmacy, agri-food, electronics, heating or cooling systems, etc.) or to treat effluents charged from housing, livestock, industry and cities before being discharged into the natural environment, or even before being reused.
The field of water is an extremely vast field in constant evolution. It brings into play a large number of very high-level technologies. It constitutes an industrial domain with factories and associated networks which can be considerable in terms of investment (CAPEX) and operating costs (OPEX).
The water industry is impacted by ecological, energy and digital developments.
This latest development is in the process of profoundly transforming the professions and techniques implemented and can make it possible to face certain challenges to be met.