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Protection for aluminum hot water boilers

DEMKOR protects your aluminum hot water boiler and your piping system

KORN offers a comprehensive solution for the safe and efficient operation of hot water systems with aluminium heat exchangers and connected piping systems made of steel and other non-ferrous metals.

Up to now, the focus has always been on protecting the supposedly most expensive component of a hot water system: the aluminium heat exchanger installed in the hot water boiler. Accordingly, the pH values of the boiler water in the piping system were usually only adjusted to this aluminium heat exchanger. The often very complex pipework system connected to it was therefore not taken into account. The protection of the complex pipework system was therefore neglected in the past. However, repairing a defective pipework system is associated with extremely high costs and long downtimes.

DEMKOR 61

Corrosion inhibition efficiency for aluminium and steel in one system

The purified tannins of DEMKOR 61 offer, in addition to their high oxygen-binding properties, an optimal corrosion protection effect for steel and aluminium in an overlapping pH value range.

This has been proven by the research results shown in Fig. 1 with the aid of EIS measurements (electrochemical impedance spectroscopy).

DEMKOR 61

Prevents corrosion in the extended pH range

The current technical water value guidelines for the protection of various metals contain a conflict between the target pH values for hybrid systems (consisting of aluminium as well as steel and non-ferrous metals).

These hybrid systems are now the rule, not the exception, despite conflicting technical guidelines. What good is the best protection for your aluminium heat exchanger if the other components of the piping system are made of steel and other non-ferrous metals and these are attacked or even destroyed by corrosion due to incompatible pH values? The use of our tannin-based product DEMKOR 61 enables an overlap of the pH value ranges at pH 8.0 to pH 9.0 with a good corrosion protection effect on all components contained, including the aluminium heat exchanger and the piping system made of steel and non-ferrous metals. With 40 years of experience in steam boiler systems, district heating networks and hot water systems, KORN has exceptional application expertise, which we put at the service of our customers with pleasure and passion.

Extended pH value range

for aluminium and steel

Manufacturer guidelines Tannin-based water treatment
Values Aluminium Steel Aluminium & Steel
pH 6,5 – 8,5 9,0 – 10,5 8,0 – 9,0
conductivity < 3000 μS/cm DEMKOR 61 dosed
Alkalinity 6 mmol/L
aluminium < 3 mg/L
iron < 20 mg/L
copper < 3 mg/L
Chlorides < 100 mg/L
Hardness < 0,02 mmol/L
Your advantages

Your DEMKOR advantages

at a glance

  • Optimum corrosion protection in a compatible pH value range
  • Protects the high investment costs in the pipework system
  • Excellent oxygen-binding properties
  • High corrosion-inhibiting efficiency due to the formation of an iron-tannate layer
  • Optimum reduction of corrosion in aluminium and non-ferrous metals in a circuit
  • Tannin-based product
  • 100% ecological, non-toxic
  • Made from renewable raw materials