Oxygen binders & reducing agents - Reliable protection against oxygen corrosion in boiler, district heating and process water systems

Sauerstoffbinder (Reduktionsmittel) dienen der gezielten Entfernung von gelöstem Sauerstoff (O₂) aus Wasser, um Korrosion an metallischen Werkstoffen zu verhindern. Bereits geringe Konzentrationen von <0,1 mg/l O₂ reichen aus, um Lochfraß, Magnetitbildung und Materialzersetzung zu verursachen – vor allem in Heißwasser- und Dampfanlagen, wo Temperatur und Druck die Reaktionsgeschwindigkeit erhöhen.

Oxygen binders work chemically by converting O₂ into harmless reaction products (e.g. sulphate). The result: corrosion protection, lower maintenance costs and standard-compliant operation - especially in boiler systems, district heating systems or feed water treatment systems.

Depending on the application, temperature, material and regulatory requirements, we use the following active ingredients, among others:

• Sodium sulphite / sodium hydrogen sulphite - proven, fast-acting at temperatures >60 °C

• DEHA (diethylhydroxylamine) - volatile, ideal for steam circuits, also protects condensate lines

• Hydrazine - very reactive, but toxic - only in exceptional cases, e.g. in high-pressure boilers

• Carbohydrazide - non-toxic hydrazine alternative with a similar effect

• Erythorbic acid / ascorbic acid - biodegradable, particularly suitable for food & pharmaceuticals

We provide individual advice on the selection of the right active ingredient, taking into account environmental regulations, material compatibility and standards such as VDI 2035 or PED.

The reaction speed depends on the active ingredient, the temperature, the pH value and the mixing intensity. Sulphite-based products typically act very quickly from approx. 60 °C, while DEHA and carbohydrazide are also active in low temperature ranges, but require a longer contact time.

Volatile components such as DEHA have an additional effect in the steam area, where they also protect the condensate network from corrosion via condensation. Good mixing and precise dosing are crucial for rapid action - ideally monitored via online oxygen measurement.

Our oxygen binders are used in many industrial and commercial applications, e.g:

• Boiler systems (steam and hot water boilers)

• District heating networks & local heating systems

• Hot water storage tank and large water heater

• Feed water and condensate treatment

• Pure and process water systems with O₂-sensitive chemistry

• Cold water systems with O₂ diffusion via plastic pipes

Oxygen is particularly critical in closed systems with steel, cast iron or copper components - here oxygen binding effectively protects against micro- and contact corrosion.

The dosage depends on:

• O₂ content in the raw or feed water

• System size and operating volume

• Temperature and flow conditions

• Consumption through chemical reactions (e.g. with iron)

Typische Zielwerte für Kesselanlagen: <0,02 mg/l gelöster Sauerstoff. Die Dosierung erfolgt meist kontinuierlich, z. B. über Dosierpumpen in den Speisewassertank oder Vorlauf. Bei flüchtigen Produkten wie DEHA wird zusätzlich die Dampfverteilung berücksichtigt.

Our specialist consultants will prepare an exact dosing calculation and supply an automated dosing and monitoring unit on request.

Yes - our oxygen binders are fully compatible with:

• pH stabilizers & alkalizing agents

• Corrosion inhibitors (e.g. molybdates, phosphates, amines)

• Antiscalants & hardness stabilizers

• Dispersants & cleaning chemicals

For steam systems, we pay particular attention to compatibility with volatile components in order to ensure steam quality, condensate flow and material protection. In sensitive systems, we test the interactions in the laboratory or directly in trial operation.

The use of oxygen binders is subject to various technical regulations and legal requirements:

• VDI 2035 Blatt 1 & 2: Definiert zulässige O₂-Konzentrationen in Heiz- und Kesselwasser. Zielwert: <0,02 mg/l

• PED (Pressure Equipment Directive): Relevance for material selection & mode of operation for boiler systems

• Drinking water ordinance / BfR: Only tested active substances may be used for systems that come into contact with drinking water (e.g. storage tank charging systems)

• TA Luft / WHG: Specifications for the disposal of conditioned water - especially for products containing sulphite

Our products meet these requirements. We support you with:
Safety data sheets
Regulatory references & test certificates
Protocols for standard-compliant application

Yes, we offer alternative oxygen binders that:

• Biodegradable (e.g. erythorbic acid)

• hydrazine-free / heavy metal-free

• DVGW or FDA/BfR compliant

• AOX-free and non-toxic for aquatic systems are

These products are ideal for food processing plants, pharmaceutical applications, sensitive district heating systems or systems with high environmental and occupational safety standards. They offer good oxygen binding with minimal residual contamination in waste water.

There is always a need for oxygen binders when free, dissolved oxygen (O₂) is present in the water - particularly critical in:

• Boiler systems & steam systems

• District heating and hot water circuits

• Feed water treatment & condensate return

• Pure water/VE systems with O₂ input through aeration or diffusion

Typical signs of insufficient oxygen protection are

• Corrosion damage to steel or copper pipes (pitting, magnetite, rust)

• Noticeable iron concentrations in the water (>0.3 mg/l)

• Oxygen input via plastic pipes or open storage tanks

• Incomplete or fluctuating pressure maintenance conditions

• Visible deposits in boilers, heat exchangers or containers

The most reliable method of detection is to measure oxygen in the water - either in the laboratory or online using optoelectronic sensors (e.g. with luminescence technology).

If the O₂ content is >0.02 mg/l (boiler water) or >0.1 mg/l (heating or district heating systems), the use of a suitable oxygen binder is strongly recommended - in accordance with VDI 2035, PED and manufacturer specifications.

We offer:

• Water analysis & SI/O₂ measurement

• System check for diffusion sources and return issues

• Recommendation and integration of suitable oxygen binders + technology