Our customer manufactures wind sensors for a variety of applications in different environments. This seal application was within ultrasonic wind sensors designed for wind turbine control. The Application For optimal performance wind turbines need critical, consistent and reliable data on wind speed and wind direction measurements. Therefore we recommended special coated O-rings for this renewable … Continued
Polytetrafluoroethylene (PTFE) is a thermoplastic polymer that can be used in a variety of sealing applications; it is particularly suitable where the application conditions exceed the parameters of elastomeric seal use, but are not as highly demanding as applications that require the use of metal seals. What is PTFE? Discovered accidentally in the DuPont™ laboratory … Continued
Renewable energy is derived from our planet’s natural resources such as sunlight, wind, rain, tides, waves, biomass and thermal energy stored in the earth’s crust. With increasing fossil fuel prices, and the very real threat of global warming and climate change to our planet; the development of renewable energy production sources is more important than ever. … Continued
3D printing has developed significantly and now performs a crucial role in many applications. 3D printed products vary from fully functional to purely aesthetic applications; with the most common application being for manufacturing. Here we discuss how our engineers use 3D printing to demonstrate a seal concept. What is 3D printing? 3D printing is typically … Continued
Hydrogen is the most common element in our universe, and is becoming an increasingly vital part in decarbonisation and a global sustainable energy future for our planet. How is hydrogen produced? Hydrogen is a clean energy solution to parts of the economy that are difficult to decarbonise. These include industrial processes, domestic and industrial heating, … Continued
Hydrogen is the most common element in our universe, and is becoming an increasingly vital part in decarbonisation and a global sustainable energy future for our planet.
Hydrogen is a clean energy solution to parts of the economy that are difficult to decarbonise. These include industrial processes, domestic and industrial heating, and hard-to-electrify transport. For example heavy-duty vehicles, ships and aircraft (where battery solutions are much less practical than they are for passenger cars). The majority of natural hydrogen is not easily obtainable and is locked away as either hydrocarbons (in fossil fuels) or water. Here we detail how seals are used for hydrogen applications.
Extracting hydrogen from either of these sources takes energy (and a lot of it!) but hydrogen becomes emission-free at the point of use. Today, 96% of the world’s hydrogen is produced using grey and brown processes, consequently, in reality it’s not very environmentally friendly at all. It is widely accepted that we need to switch to and expand green hydrogen production. However, the electricity sources for green hydrogen (solar, wind, etc) are not always located where the hydrogen needs to be used. Consequently, cannot be turned on and off as energy demand fluctuates.
Hydrogen can be obtained in a variety of different ways, and each of these methods is generally categorised by a different colour.
Grey hydrogen is produced by reforming natural gas (methane).
Brown hydrogen is produced by converting carbon rich materials (such as coal) into hydrogen and carbon dioxide. These are common processed, but both result in substantial carbon emissions.
Turquoise hydrogen is produced by the pyrolysis of methane at temperatures over 1000°C. Solid carbon is a by-product which can then be used or buried without emitting greenhouse gases or causing groundwater pollution.
Blue hydrogen is generated by the steam methane reforming of natural gas. This generates large amounts of CO2 which must then be captured and safely stored.
Pink hydrogen is created where large amounts of electricity is used to chemically split water into hydrogen and oxygen. Manufactured from a nuclear power plant, it’s free from ongoing emissions (other than those emissions produced in building the nuclear power station). The oxygen can be used by industry or vented to the atmosphere, with no negative effects to the environment.
Green hydrogen is also produced by electrolysis of water. However, the electricity required is taken purely from renewable sources such as solar, wind, tidal and geothermal processes. This is widely regarded as the ONLY totally clean hydrogen extraction method.
Today, 96% of the world’s hydrogen is produced using grey and brown processes. This means in reality it’s not very environmentally friendly at all. It is widely accepted that we need to switch to, and expand green hydrogen production. However, the electricity sources for green hydrogen (solar, wind, etc) are not always located where the hydrogen needs to be used. Consequently, cannot be turned on and off as energy demand fluctuates.
Sealing hydrogen presents challenges and we need to consider the following parameters when designing a sealing solution.
Hydrogen can be within a carrier. Therefore the chemical compatibility requirements of the carrier medium (e.g. ammonia or liquid organic hydrogen carriers) need to match the sealing materials specified.
EPDM elastomer based solutions are often the most cost effective for seal applications in hydrogen with no particularly high demands in any one area. For permeation resistance, we offer chlorobutyl elastomer or polyurethane seals.
In high pressure applications, alternatives are available. For example, elastomers or polyurethanes with high extrusion resistance and resistance to rapid gas decompression, or PTFE which is not affected by RGD.
In electrolysers and fuel cells, the purity and cleanliness requirements can be met with materials and treatments we frequently use within the semiconductor market. In applications below -60°C, elastomers become hard and brittle, but PTFE, PCTFE and metal sealing solutions can be used down to cryogenic temperatures.
For high temperature applications, some FKM or even FFKM elastomers can be used up to 220°C or even 300°C. However, the normal preference here would be PTFE sealing solutions.
Metal seals are capable of even higher temperatures up to around 870°C. Metal seals can also have soft coatings such as tin or indium to achieve gas tight sealing, or gold or silver to reduce the risk of hydrogen embrittlement.
The hydrogen industry is technically vast and challenging for sealing applications. Extremes of temperature, alongside demanding pressure and chemical resistance requirements are challenges. Additionally, stringent leakage limits and associated safety requirements.
Applications typically demand long service life and in certain cases require parts with high levels of technical cleanliness and purity. There are requirements for elastomer, polyurethane, PTFE and metal sealing solutions. It is important full consideration of the application to select the most appropriate seal design and materials.
Learn more about how we serve customers in the Hydrogen & Renewable Energy Industry HERE