As energy challenges focus industry's attention, water becomes a strategic resource to be managed with care. Every drop counts in this tandem: from the collection of the resource to the discharge of wastewater, the rational use of water and energy efficiency are closely linked. Faced with this reality, the recent decree on the use of water in the food industry invites in-depth reflection and concrete action.
We met Olivier Barrault, President of ATEE Région Grand Ouest and CEO of Elodys International, a company specializing in helping manufacturers save water and optimize industrial washing processes (CIP). We addressed the following question: why has it become essential to integrate these two environmental issues for sustainable industrial performance?
In recent years, a great deal of attention has been focused on energy challenges, from reducing carbon emissions to managing ever-increasing costs. Meanwhile, industry has neglected the issue of water, regarding it as a virtually free and inexhaustible resource. However, the facts are clear and undeniable: although the price of energy may fluctuate wildly, it always remains available, while if water runs out, the plant's very activity is threatened.
Water shortages can have major strategic consequences, which manufacturers are only just beginning to realize, particularly since the drought of 2022.
In the industrial field, the relationship between energy and water is both profound and complex, throughout the water cycle in a plant. As early as the drilling operation stage, the question of water's energy recovery can arise, due to its geothermal potential, whether to produce heat or cooling.
Then comes the subject of water's geothermal potential.
Then comes the subject of water treatment. Indeed, the diversity of industrial needs in terms of water quality (softened, demineralized, ...) underlines the importance of appropriate management of the conditioning of this raw water, as each type of water has an energy cost. The right quality of water must be determined according to its use. Take washing, for example: certain qualities of water make washing less efficient, which can lead to over-consumption and reduced quality control. What's more, we shouldn't forget that not only is water treatment energy-intensive, but a poor management of its quality can also affect the energy efficiency of utilities such as boilers, cooling towers and evaporative condensers.
Water plays a crucial role as energy vector in industrial processes, promoting the transfer of heat, cold and even mechanical energy. Its ability to transfer energy from one point of production or extraction of calories to another is essential. Hydraulic management of this distribution is a major issue in terms of energy savings (particularly for pumping), as well as quality and productivity for end uses (flow rate, pressure, contamination).
Finally, wastewater discharge management must be seen as an energy issue in its own right, and not as an inevitability. It's important to bear in mind that the energy consumption of biological treatment at a wastewater treatment plant depends closely on the organic load and volume of water discharged.
In summary, every stage of the water cycle in an industrial process, from extraction to wastewater disposal, is closely linked to energy efficiency.
In order to use these vital resources efficiently and avoid malfunctions, a careful, holistic analysis is needed to master the issues, interactions and financially and environmentally effective solutions.
Legislation is evolving and adapting to address this crucial water resource issue, which is directly linked to ongoing climate change.
This decree aims to correct past decisions concerning water use, in a context where this resource was considered almost inexhaustible, particularly in industry. Health and food safety regulations sometimes force manufacturers to consume too much water, out of an excessive sense of precaution. In many cases, regulations only considered the use of so-called " potable " water, without taking into account its truly necessary level of quality.
For decades, perfectly reusable process water has been thrown away, whether treated or not. This decree now allows for an improvement in water reuse for agri-food companies.
More and more manufacturers are coming under pressure from the DREAL due to drought decrees. No ideal solution without asking the right questions. So, the first necessary step is to carry out a complete audit of their water requirements, based on accurate mapping. This enables us to understand where, how much, how and why a certain quantity and quality of water is consumed. This audit leads to a qualified action plan, which can be prioritized according to the stakes, complexity and of course the profitability criterion. This approach confronts the industrialist with realities of which he is unaware, including in terms of industrial performance. In the food industry, for example, regular cleaning of production equipment is essential to guarantee product quality. However, such cleaning often accounts for more than half of water consumption, a significant proportion of energy consumption, the use and discharge of chemicals, as well as lost productivity due to process downtime.
Then the question arises: how can I reduce my consumption without disrupting my business and keeping my expenses under control?
The 3Rs (Reduce, Reuse, Recycle) are often evoked. Reducing is the priority : It's preferable to limit water consumption, as reuse or recycling processes can prove costly in terms of investment, operational costs and human resources for monitoring, maintenance and long-term management.
From the energy point of view, a key line of thinking is to identify sources of fatal energy and potential points of recovery. This presupposes first checking that this need is compatible in terms of temperature and flow, but also properly optimized. When an industrial site's energy balance is drawn up, cleaning in place (CIP) is often identified as an important need to be met. However, there is a tendency to wrongly assume that this need is unavoidable. So if it's possible to reduce this need by 50 to 75%, and at more accessible temperature levels, why invest in an expensive energy recovery system for CIP? It is therefore important to consider the option of regenerating and reusing detergent solutions (" GreenCIP ") before embarking on a fatal energy recovery project. What's the point of recovering calories for a need that will disappear tomorrow?
The real issues often lie at the heart of the plant, with problems that are sometimes more complex and global than those related to energy. For example, in the energy field, the Pinch method is often used to match available sources of fatal energy with simultaneous energy needs, over a given perimeter. For water, the method is similar, but more complex, as not only must flow, temperature, volume and physico-chemical quality be taken into account, but also the potential contamination of this reclaimed water. It is therefore important to be cautious and methodical.
In order to improve industrial performance, a holistic approach is required. Energy efficiency and optimal water management are integral elements of this overall performance. Let's take a concrete example: one of the actions carried out on CIPs is aimed at optimizing washing times, which frees up manufacturing time and therefore the operational efficiency of lines. This has a positive impact on a number of industrial performance indicators.
It is therefore entirely possible to improve environmental performance while optimizing industrial performance, although these notions are often wrongly opposed.
Experience has shown that approaches focusing on energy and water highlight areas of non-performance that are often ignored. Industrialists tend to take a vertical view of their site's performance. By taking water and energy into account, they can also opt for a cross-functional approach that sheds light on the gray areas where quality and productivity are not under control. By using the right energy performance indicators, it's possible to detect, even anticipate and solve these problems.
To effectively integrate water, energy and carbon issues into their strategy, manufacturers need to adopt a decompartmentalized approach. The key to success lies in facilitating close collaboration between stakeholders in Manufacturing, Quality, New Works, Maintenance and Environment. The profile best suited to ensuring this cross-functional collaboration is often that of a Methods or Industrial Performance manager.
Team training is a central element of this transition. By developing internal skills for efficient water and energy use, the site will be better organized to identify and collaboratively manage future projects. We can't expect everything from the outside. For example, historically there have been very few real thermal engineers working on energy utilities, where we more commonly come across profiles such as mechanics, electrical engineers or automation engineers. Yet this is an essential skill. I've also noticed this problem in the CIP sector, where some detergent suppliers can "take advantage" of their customers' lack of knowledge of wash chemistry. The detergent vendor's interests are not always aligned with those of the industrialist, and even less so with the objective of sobriety and reduced environmental impact.
In addition, it's important to remember that the detergent supplier's interests are not always aligned with those of the industrialist.
In addition, it's essential to measure and track performance to maintain commitment and make steady progress. It's difficult to stay on course and achieve long-term goals without clear, measurable indicators, because as the saying goes : " you only master well what you measure well "
The previously mentioned initiatives are aimed at improving what already exists, but it's essential to look at future investments that will determine tomorrow's consumption. Thus, the engineering of any new project (Process and Utilities) must take into account environmental performance, particularly in terms of water, energy, greenhouse gases and discharges. Failing to do so, the site risks missing out on real opportunities for the long term.
It is also necessary to integrate a water and energy master plan, as well as a medium-term decarbonization plan, into the site's industrial master plan. Achieving such a transformation takes time and regular stages of decision-making and revision of objectives.
Finally, to anticipate all opportunities, industrial management must stay alert to emerging solutions on the market. This is the case for disruptive technologies such as GreenCIP (infinite reuse of laundry detergents), but also for innovative solutions such as the one developed by an American startup, AquaCycl. Their industrial wastewater treatment technology produces its own electricity from a specific family of bacteria that both digest organic matter and generate an electric current. This self-generation of electricity can thus cover 30 to 40% of a wastewater treatment plant's electricity consumption.
Industrial managers face major challenges when it comes to energy and water. On the one hand, the financial risks associated with energy are becoming increasingly worrying as the years go by. On the other hand, the issue of water is marked by risks of rarefaction, highlighting the imperative need for effective management. A successful approach requires a strategy focused on control, accompanied by appropriate public policies, such as subsidies linked to environmental criteria.
In an increasingly competitive industrial context, it is crucial to adopt a holistic approach in order to build a strategy that involves all potential issues and impacts. Water is a finite resource within a given territory. Its availability is subject to unpredictable fluctuations linked to ongoing climate change, and potentially to radical arbitrations on the part of the administration.
In addition, water involves close interactions with other actors such as agriculture and local communities, thus underlining its more pronounced ecosystemic character than that of energy. Waste management and recycling require collaboration with a variety of stakeholders, and appropriate and effective regulation by the authorities.
In highly liberal societies such as the USA, many industrialists adopt a migratory locust logic that moves as it depletes its resources. For example, agri-food manufacturers are gradually moving from the southern states to the Great Lakes states in search of new water resources, without fundamentally questioning their mode of production.
In the United States, for example, there is an abundance of water in the Great Lakes.
Apparent abundance is never a good or sustainable advisor, so we need to take advantage of these new constraints to turn them into opportunities and key factors in tomorrow's competitiveness.