Innovating Together: A market-ready, extruded profile seal has been developed under the Industrial Services Division’s direction for use in the production of hydrogen. It was developed in short order and is now being used in alkaline electrolysis processes. The participants in a second project are now planning new, fundamental developments for the next generation of electrolyzers.
“Hydrogen – A Resource for the Decarbonized Future.” That is a headline in a guide to hydrogen that the Industrial Services Division authored for the chemical industry. The white paper describes the development capabilities of Freudenberg Sealing Technologies (FST) relating to hydrogen applications.
In a project for a well-known European maker of alkaline electrolyzers, FST has shown that these descriptions are not merely theoretical – they represent real-life practice. The Industrial Services Division’s technical department has developed a new sealing solution in close cooperation with the Lead Center Special Sealing Industry (LC SSI), Freudenberg Technology Innovation (FTI), and the customer.
The timeframe was tight, and, as the electrolysis stacks already existed, the degree of freedom in designing the seal was limited. The installation space was already set. “We jumped right into the details and ran numerous calculations and tests, and succeeded in optimizing the existing design of the profile seal,” said Mark Boggasch, Technical Service & Innovation, Global Process Industry. With the unaided eye, one can see the change from the original flat design of the competitive product that had been used. It now has the spherical geometry of a profile seal. “The functional overlap with its partner elements was increased with a simultaneous reduction of the critical groove fill of the initial design,” Boggasch explained.
The second focus was on development of a permanent and sustainable material to replace asbestos, a known health hazard. The challenge: In alkaline electrolyzers, the sealing material must withstand a highly concentrated potassium hydroxide solution, as well as oxygen, “which drive deterioration.” It must also have a long lifespan and withstand enormous pressure and increased temperatures.
Oliver Arnold, Senior Specialist Material Engineering, LC SSI, and Dr. Robert Rotzoll, Business Development Manager, Global Process Industry, immediately analyzed FST’s portfolio of materials. In the short time available, an EPDM material emerged as the best solution. In specially executed storage trials, it exhibited better resistance to potassium hydroxide and oxygen than the material of a rival company.
500 Kilometers per Year
Since a single profile measures about 5 metres in length for each electrolysis cell, the seals needed to be manufactured via endless extrusion. “Long-term, we are assuming an annual production volume of 500 kilometers,” Rotzoll said. Currently, the seals were at the customer for evaluation and the first series quantities were ordered.
But there is more. Shortly after the first contact, it turned out that the customer was interested in a more in-depth collaboration with FST with the next generation of electrolyzers in mind. “We are just in the process of defining the content and the framework of this second, significantly more advanced development project,” said Wulf Geiselhart, Technical Service & Innovation, Global Process Industry. Then FST will be able to let its existing knowledge flow into the design of the sealing environment to improve the overall system.
Based on projections, the demand for hydrogen is expected to grow explosively in the chemical industry and in sustainable energy carriers, storage systems and fuels for fuel cells, serving as a key resource for a decarbonized future. In this light, these kinds of basic development projects with customers are tremendously important for FST’s future. The project team agrees that “Innovating Together” offers the opportunity to gain experience, learn and develop while collaborating with customers. The projects become a good reference and demonstrate expertise in development. Never standing still, always making progress and setting standards in new fields of application – in the end, that is a component of FST’s DNA.
