Sustainable management of cooling water

Many industrial processes rely on cooling water. Given the importance of water in the process flow, it is worth taking a very close look at its quality and composition. Linde is using digital systems to boost efficiency and sustainability.

  • Many industrial plants rely on cooling water. Its quality and composition have an impact on the overall efficiency and sustainability of the plant.
  • Linde has teamed up with several water treatment companies to optimize the management of cooling water – resulting in both financial and environmental gains.
  • The solution uses chemical sensors connected to a digital network to reduce consumption of cooling water and chemicals required at Linde’s large-scale plants.

Things can really heat up in industrial plants. Many processes run at high temperatures, with machines getting extremely hot or producing hot liquids and gases. That is why cooling processes play such an important role – as does the water needed for the cooling. “Cooling water is an invaluable resource for our core business. We need it not only to cool down energy-intensive machines that produce gases, but also to stop chemical reactions occurring by lowering the temperature,” says Carsten Taube, a chemist and Group Lead Water Service at Linde Engineering.

Less lime for more efficiency

There is a lot more to cooling water than meets the eye, however. No two sources are the same with some waters containing more dissolved minerals than others. It all comes down to the hardness of the water. Everyone knows how this can affect appliances like kettles, dishwashers or washing machines. If the water has its source in the Alps, for example, it is going to contain a lot of dissolved lime. This can lead to the unwelcome build-up of limescale, causing damage to the machines over time. The insulating effect of the limescale also increases the energy drain. In industrial plants, this has a hugely detrimental impact on efficiency, not to mention the additional volumes of water needed because of the deposits. “Every micrometer of limescale reduces asset efficiency – which of course gives us an enormous incentive to explore optimization potential,” points out the chemicals expert. “The bottom line is that sub-optimum cooling water could cost you an additional 600,000 euro per plant – every year.”

Sub-optimum cooling water could cost you an additional €600,000 per plant – every year.
Cooling water management in process plants
Optimizing the cooling water system in large-scale industrial plants can reduce the consumption of both water and chemicals required, thus contributing to sustainability efforts and lowering operating costs overall.

Getting the chemistry right

Taube has been responsible for managing the cooling water in Linde’s internal water expert network since 2012. Over time, he has demonstrated how water quality strongly impacts plant performance. He stresses how important it is for plant engineers to factor in the quality of the cooling water as early as the materials selection stage: “In Norway for example, limescale is not a problem. Instead, the predominance of granite rock in the landscape means that the water there can very easily corrode standard building materials. He maintains it would be too expensive to install a chemical pretreatment step on completion of the engineering work. The solution therefore lies in materials that are less susceptible to corrosion.” Chemical additives like corrosion or limescale inhibitors do make sense, however, in the presence of dissolved lime and other salts in cooling water. They can increase both the performance and service life of an industrial plant. “We are looking towards both environmental and financial optimization when we analyze and monitor the key parameters of a cooling water system. Our aim is to maximize asset efficiency with a minimum of intervention,” according to the Linde expert. Better metering of chemicals and lower water consumption can also help operators to reduce running costs and manage their plant more sustainably. “The chemicals industry is the biggest consumer of water in the manufacturing sector – so every improvement we make to water management is good news,” adds Taube.

Are you interested in a quote?

Send an RFP

Real-time analysis and adjustment of water chemistry

The chemist and his team, which is responsible for assessing water technology at Linde’s plants, act as an interface between the water treatment provider and the people in charge at the Linde plants. “We cooperate closely with our water treatment partner who provides the necessary equipment.” This includes a digital technology package for water monitoring. Every cooling system is fitted with analytics technology that uses chemical sensors to measure the water chemistry in real time. This allows the metering of chemicals to be adjusted dynamically for optimum results. The system is also connected to a cloud service with alarm functionality. An additional benefit is that this data can be fed in to Linde’s own digital infrastructure, where it is combined with existing operating and process data. Digital analytics tools and algorithms then use the collected data to support predictive maintenance. The Remote Operation Centers (ROC), which remotely control around 1,500 Linde plants around the world, are also digitally integrated into the system.

Cooling water computer with sensors
As this example from Germany shows, chemical dosing can be adjusted quickly and in the best possible way with the help of sensors and a digital technology package.
Hydrogen and synthesis gas plant in Leuna, Germany
No two sources of water are the same. But if the cooling water system is aligned with the regional conditions, there is less risk of limescale or algae deposits building up. The benefits for industrial plants are longer maintenance intervals and extended service lives.

Digital infrastructure improves efficiency and performance

“We have also developed individual key performance indicators and fed them into the system. This means that we can not only check and adjust the water composition as soon as we become aware of a problem, but we can also use the data to optimize the composition before it even comes to an alarm,” explains the Linde expert. This can be a major advantage in places where the water quality fluctuates – as it often can in rivers. Taube mentions the Ganges in India as an example. If industrial plants in the region wish to use water from the river for cooling purposes, they need to take extreme seasonal variations into account. Whereas the water quality is very good during the time of the monsoon, the river carries a high load of contaminants and fertilizer residues during the dry season. “This is where automated systems for monitoring the water chemistry really come into their own. They are able to send an alarm before the quality risks taking a nose-dive, and then initiate corrective measures before damage is caused to the industrial plant,” says Taube. A comprehensive and regionally adapted cooling water management system is therefore essential for optimizing – and ideally reducing – the consumptionof chemicals. Plants perform better and require less maintenance if the cooling water leaves no limescale or algae deposits and its corrosive effects have been mitigated by inhibitors. This allows plants to reduce their energy and resource consumption as well as their overall cooling water requirements.

Optimum management of cooling water to save costs

In Germany, where Linde has its densest network of plants, the initial rollout will see 25 open cooling systems at 20 locations digitally integrated and connected with a water monitoring computer. “We regard ourselves as a technology leader in cooling water management, but our service extends far beyond the delivery of technical equipment. We also want to build cooling water expertise at our locations in the long run,” explains Taube. To this end, Linde intends to organize special training so that every plant has its own water expert on site, who is then also the contact person for the corresponding water treatment partner. “We have already received very positive feedback regarding our open-minded, progressive and well-prepared water management approach. For my team and for myself, this confirms that we are on the right track,” adds Taube. The figures also bear this out: The Linde expert is anticipating Germany-wide cost savings of over three million euros over the next five years thanks to these digital innovations.

By optimizing cooling water, our aim is to maximize asset efficiency with a minimum of intervention.

Sustainability in action

The German Chemical Industry Association (Verband der Chemischen Industrie e.V. or VCI) has called Linde’s proactive approach to cooling water “an excellent example of how digitalization can contribute to environmental protection”. Linde Engineering and Linde Gas Produktionsgesellschaft mbH & Co. KG submitted their joint project on the theme of “sustainable water management” for the Responsible Care Competition – and received their certificate in July 2020. “Our solution has allowed us to operate more cost-efficiently and reduce our carbon footprint. We have therefore greatly improved our environmental and economic sustainability performance,” according to Taube. “Our water network doesn’t just overcome technical and chemical challenges, however. We also have to network different stakeholders. Our objective is to raise the level of awareness around this topic,” concludes the Linde expert. This will no doubt take time, but it will also create a major impact which will pay off in the long term – in more ways than one.

Would you like to know how our products and services can support your business?

Send me more info