Efficient water treatment at District Heating

A success criteria of good water treatment in district heating systems is optimum technical and economical operation both in the short and in the long run. Likewise, low chemical consumption is a success criteria, since the environment will be the least stressed by leakage of district heating water and at the same time, the risk of corrosion will be reduced.  This means:

  • Minimization of corrosion and formation of deposits.
  • Optimum plant and operating economy.
  • Minimum maintenance costs.
  • Minimum internal and external environmental impact.

SILHORKO-EUROWATER has designed and supplied a new plant for producing makeup water for the district heating grid in Aalborg, Denmark. The plant is a vital part of Aalborg district heating’s maintenance plan, allowing the main makeup production facility at another location to be shut down on a regular basis for maintenance.

The plant consists of chemical-free solutions with high water utilization. More specific an UPCORE softening unit and a reverse osmosis unit. The RO unit is an RO-PLUS unit, optimized for high water recovery and low energy consumption in order to minimize operational costs. RO-PLUS units are designed for a recovery rate up to 90% compromising neither the reliability nor the water quality. The demineralized water is stored in a 25 m3 clean water tank which also acts as a buffer.

SILHORKO-EUROWATER was selected as a supplier because the solution could provide the lowest Total Cost of Ownership (TCO) over a period of 15 years.

Recently Danish District Heating Association published its recommendations for correct water treatment for district heating with a view to prevent corrosion of pipes etc. – which could cause water leakages (loss of water and energy), intake of untreated water through the network as well as interruption of supply to the customers of the district heating company. Correct water treatment strongly influence lifecycles and maintenance requirements for key assets such as pipes, fittings, boilers, heat exchangers etc.  The recommendations apply to all water-born district heating systems irrespective of operating temperature. In other words the recommendations are all about good asset management.

Download the recommendations in English, go to

About author

Silhorko-Eurowater (EUROWATER) - A Grundfos Company - brings years of experience and specialised know-how within high-quality water treatment. EUROWATER supplies customers in a broad range of industries and application areas, including boiler water, process water, cooling water, rinse water and drinking water.

Primary contact
Jens O. Gjerloeff

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