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Hydrogen and oxygen valves for electrolyser from Battolyser Systems

In view of the growing importance of hydrogen production and storage technologies, the role of companies such as Battolyser Systems is crucial. A. Hock provided the innovative company with two control valves for electrolysis processes. The valves had to fulfil the highest requirements, from low leakage values, a high degree of cleaning and strict safety standards.

Battolyser Systems - a key player in the energy transition

Battolyser Systems has taken a pioneering step with the development of the world's first integrated battery electrolyser system, known as Battolyser®. The innovative product combines battery storage and electrolysis in a single system. It stores electricity and splits water into hydrogen and oxygen at the same time.

The aim of the technology is to improve the storage and utilisation of renewable energies and enable the production of green hydrogen. The company is therefore an important player in the energy transition and in the decarbonisation of the economy.

Excursus: What is an electrolyser?

An electrolyser is a device that is used to carry out electrolysis. In the chemical process, electric current is used to decompose chemical compounds. The main application is in the production of hydrogen. Water (H2O) is broken down into its components hydrogen (H2) and oxygen (O2).

Water electrolysis is particularly interesting for sustainable energy technologies. As a clean energy carrier, hydrogen can be used as a fuel for hydrogen vehicles, to generate electricity or can be utilised in various industrial processes, e.g. in refineries or the chemical industry.  

Find out more about hydrogen electrolysis in the magazine article.

The pitfalls of hydrogen and oxygen

The gases hydrogen and oxygen released during electrolysis require special precautions when handling them. Hydrogen is the lightest and most volatile element in the periodic table. Although it is neither toxic, corrosive nor radioactive, it still has a few pitfalls in store: Hydrogen likes to penetrate the crystal lattice of metals and makes them brittle. This results in accelerated crack growth or material failure.

More on the topic of hydrogen embrittlement

Oxygen is a by-product of electrolysis. Although it is not flammable itself, it is extremely flammable and explosive in the presence of flammable materials. Even slight contamination, e.g. with oil or grease, can cause explosions in the presence of oxygen. The safety standards and requirements for fittings, pipework and system components in oxygen systems are correspondingly high. TRGS 407 (Oxygen hazards) applies here, for example.

Good to know: Pipelines and equipment with an oxygen content of over 23.5% are considered oxygen systems


The requirements for the hydrogen & oxygen valve

A. Hock supplied Battolyser Systems with two control valves, one for hydrogen and the other for oxygen applications. The valves had to fulfil strict criteria:

Hydrogen valve

  • low leakage values
  • ultra-fine flow control down to KVS 0.01
  • approved and tested in accordance with TA-Luft, DGRL, NACE
  • High-quality materials that prevent embrittlement
  • High internal and external tightness

Oxygen valve:

  • Metallic material: Austenitic stainless Cr-Ni steels with a combined chromium and nickel content of at least 22%.
  • chromium and nickel content of at least 22%, e.g: 316 stainless steel
  • Non-metallic materials may only be used if they have been approved by a recognised body (e.g. BAM)
  • Precise control of the flow rate
  • the valve through which oxygen flows must be technically free of oxidisable substances on the surfaces touched by the oxygen. We guarantee a high degree of purification of < 55 mg/m2
  • Leakage-free: possibility of complete sealing
  • Resistant to high pressures
  • Temperature resistant

The result

Despite the high requirements, A. Hock was able to provide perfectly matched control valves for the electrolysis processes at Battolyser Systems, which are characterised by high quality and safety. Special precautions apply above all to oxygen valves. In order to maintain the high degree of cleaning, the valve was packaged in such a way that the wetted parts are absolutely free of grease and oil.


Further references in the field of hydrogen

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Andreas Schalwig

Andreas Schalwig

Technical Sales

I’m happy to help you with projects and enquiries in the field of valve technology as well as measurement and control technology. I have more than 15 years of experience in the dimensioning of control valves and actuators. What’s more, I help customers from all over the world to modernise their industrial plants.