Water treatment for district heating

district heating pipes
Avoid corrosion using correct water treatment and protect your asset investment

District heating systems utilizes the heat from a wide variety of energy sources such as combined heat and power plants (CHP), Waste-to-Energy (WtE) plants, boiler heating plants, surplus heat from the industry, solar thermal systems as well as geothermal heat and large-scale heat pumps. District heating water, however, is not just heated water. The water quality and how the water quality is produced are of great importance.

Extend the life of the pipes with correct water treatment
The main goal of water treatment is to prevent corrosion, deposits, and pipe fractures. Pipe fractures cause interruptions of supply to customers as well as loss of valuable water and the risk of intrusion of untreated water, which can pollute the treated water in the distribution network.

The Danish District Heating Association, representing almost 400 district heating companies in Denmark, has published its recommendations for correct water treatment in the District Heating sector.
To protect your investment get your free copy here.  


How to avoid corrosion

Oxygen, salts and particles in the water can create corrosion. The oxygen reacts with the steel in the district heating pipes while the salts act as catalyst for the electrochemical corrosion.

By removing salts and oxygen as well as adjusting the pH, the basis for corrosion – including microbial corrosion – will be removed.



Make-up water & Circuit water for district heating

Optimum make-up water and circuit water must be demineralized, deaerated (oxygen), free of mechanical impurities, and pH-adjusted to avoid corrosion and fractured pipes.

In this leaflet we put water on the agenda! Read about chemical free make-up water and how to reduce pollution by filtering a partial stream of the total flow. Click here to download the leaflet (PDF 5,17 MB). 

Make-up and circuit water for district heating


Reduce pollution with a magnetic insert

Raw water intrusion, corrosion products, and suspended magnetite will inevitably occur in the district heating circuit causing pollution and at worst breakdowns. 

As a minimum, particle filtration with bag filter and magnetic insert is recommended. A magnetic insert in the particle filter efficiently collects magnetite residue from the circuit water. 
If you want to hear more about this solution, please don't hesitate to contact us.  

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If the water is treated correctly, boilers, valves, fittings, installations, and undergroud piping can last for many years. The Danish District Heating Association has published its recommendations for correct water treatment to increase lifecycles of these key assets.



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The Danish District Heating Association




Total cost of ownership

At EUROWATER we believe that a comprehensive solution is based on total cost of ownership, not on lowest possible purchase price only. This was the reason EUROWATER was selected by a leading district heating company in Aalborg, Denmark. The new plant for producing makeup water could provide the lowest total cost of ownership over a period of 15 years.  

The plant consists of an UPCORE softening unit and a reverse osmosis unit. The RO unit is a RO-PLUS unit, optimized for high water recovery and low energy consumption to minimize operational costs. Read how you can save water and energy with our RO-PLUS technology

UPCORE softening unit and a reverse osmosis unit at Aalborg District heating company, Denmark



Remove oxygen with a chemical free solution

Skanderborg-Hørning District Heating in Denmark has recently installed a membrane degasser for removing oxygen from the feed water. In this short video (3 min.) Lars Jørgen Dam, Head of production at Skanderborg-Hørning District Heating, explains how they work with correct water treatment to prevent corrosion and extend the lifespan of the plant.

Corrosion prevention for District Heating


Rent a mobile water treatment plant tailored according to your need 

If a temporarily water treatment problem arise, you can easily take care of it by renting a EUROWATER mobile water treatment plant. The video (2 min.) gives an example of, how the mobile water treatment plant handles a filling of thermal energy storage. 

Whether you need drinking, disinfected, softened or demineralized water, we have a mobile solution. Read more about our mobile water treatment plants or contact us for further information and reservation.   

Rental of mobile water treatment plant