Hydrogen technology is rapidly advancing across industries like energy, transportation, and chemical processing. To ensure safe and efficient operation, accurate instrumentation is crucial. Pressure and temperature transmitters play a key role in hydrogen applications. In this post, we’ll explore how these instruments meet hydrogen’s unique demands, focusing on material selection, standards compliance, and design considerations.
Hydrogen’s Unique Properties
Hydrogen poses specific challenges due to its unique characteristics:
- Small molecular size: Hydrogen can easily leak if inappropriate materials or seals are used.
- High diffusivity: It tends to permeate some materials, creating potential safety risks.
- Flammability: Hydrogen is highly flammable, requiring strict safety measures.
- Varied temperatures and pressures: Hydrogen systems operate in extreme conditions, from cryogenic temperatures to high pressure environments.
Given these challenges, pressure and temperature transmitters must be carefully designed and built to withstand these conditions.
Pressure Transmitters for Hydrogen Applications.
Key Materials
Pressure transmitters used with hydrogen require materials that resist permeation and embrittlement. Common materials include:
- 316L Stainless Steel: Resists corrosion and hydrogen attack.
- Hastelloy®: Offers enhanced protection against cracking.
- Tantalum: Often used for its resistance to hydrogen diffusion.
Compliance and Standards
Pressure transmitters in hydrogen applications must meet several critical standards:
- ATEX Certification: Ensures explosion-proof safety in hydrogen environments.
- IEC 61508 (SIL): Ensures the reliability of transmitters in safety systems.
- ISO 11114-2: Guides the selection of materials that resist hydrogen permeation and embrittlement.
Transmitters are calibrated for high accuracy, often within ranges of up to 700 bar or more, depending on specific applications like hydrogen storage or transport.
Temperature Transmitters for Hydrogen
Material Considerations
Temperature transmitters also require high-performance materials to withstand hydrogen environments. Stainless steel is commonly used, and special coatings may be applied to improve resistance to hydrogen diffusion.
Temperature Range
Temperature transmitters in hydrogen applications must operate under extreme conditions:
- Cryogenic Sensors: Built for very low temperatures (down to -253°C) in liquid hydrogen systems.
- High-Temperature Sensors: Able to withstand temperatures up to 600°C, crucial for hydrogen combustion and fuel processing.
Standards for Temperature Transmitters
Like pressure transmitters, temperature instruments must comply with key certifications such as:
- IECEx: Ensures equipment safety in explosive environments.
- ASME B31.12: Governs safe design for hydrogen piping and instrumentation.
Ensuring Safety
Transmitters for hydrogen must include several safety features to ensure reliable performance:
- Explosion-proof housing: Prevents leaks and ignition in the event of a failure.
- Overpressure protection: Protects transmitters from damage under high-pressure conditions.
Applications in Hydrogen
Transmitters are essential across the hydrogen value chain, including:
- Production: Used in electrolyzers and reforming plants for precise control.
- Storage and transport: Necessary for monitoring high-pressure hydrogen storage tanks or cryogenic systems.
- Fuel cells: Ensuring safe, efficient hydrogen usage in vehicles.
- Refueling stations: Monitoring pressure to maintain safety during hydrogen vehicle refueling.
Conclusion
Pressure and temperature transmitters in hydrogen applications are critical in ensuring safe, efficient operation in hydrogen systems. By adhering to strict material standards and incorporating safety features, they meet the unique challenges posed by hydrogen applications. As the hydrogen industry grows, advanced instrumentation will continue to play a pivotal role in keeping hydrogen systems safe and reliable.
Learn more about our measurement instrumentation scope in our detailed guide