Enhance efficiency and safety of green hydrogen production

The production of green hydrogen involves the electrolysis of water. This process requires a substantial amount of water. A sustainable use of water resources is a valid concern when producing green hydrogen. Pure or ultrapure water has to be used in electrolysis to minimize the presence of impurities that could interfere with the chemical reaction and reduce the efficiency of the green hydrogen production process. High-purity water is obtained through processes like reverse osmosis.

• Conductivity is a key measurement parameter in ensuring the quality of water. Our digital conductivity sensor CLS16E with Memosens 2.0 technology enables data storage and contactless data transmission.
• Flow meters are used for monitoring conductive liquids and ensure the reliability of the electrolyzer's water feed. The Promag W 10 is the world's first electromagnetic flowmeter for unrestricted installation measurements.
• In case of alkaline electrolyzers, typically vortex meters like Prowirl F 200 are used for measuring the pure water.
• Measuring pressure during the preparation of water for electrolysis is essential to detect blockages in filtration and osmosis. Our Cerabar PMP51B is a reliable and easy-to-use sensor for reducing systematic faults in green hydrogen production.
• Measuring level is crucial for maintaining a consistent supply, preventing dry running and promoting resource efficiency. Levelflex FMP51 is suitable for hydrogen and oxygen separators and highly resistant to corrosive substances.
• TOC and Silica content vary based on the source of water (municipal, rivers, ground water, reclaimed water, etc.). Rely on our Silica analyzer CA80SI and TOC analyzer CA78 for accurate measurement.

Unlike other types, AEM electrolyzers use an alkaline solution and a membrane that transports hydroxide ions (OH-). At the anode, water splits into oxygen and hydroxide ions. The membrane carries the hydroxide ions to the cathode, where they react with electrons (from the electrical supply) to form hydrogen gas. AEMs have the potential advantage of using lower-cost catalysts than PEM electrolyzers.

• Maintaining the delicate balance between water supply and water removal is crucial for membrane stability and efficiency. This can be achieved with Promag P 300 electromagnetic flowmeter.
• Gas crossover or cross-membrane permeation can be mitigated by operating the cathode (H₂) side of an electrolyzer at higher pressure than the anode (O₂). Monitoring the differential pressure can be crucial to ensure the electrolyzers are operating correctly, especially when the two sides are operating at similar pressures. This requires careful monitoring with Deltabar PMD75B.

High-temperature electrolysis or Solid Oxide Electrolysis (SOEC) is an emerging technology relying on steam, instead of liquid water or electrolyte. Operating at high temperatures (600-1000 °C) greatly increases the efficiency of the electrolysis process, especially when integrated with waste heat or other high-efficiency heat sources.

• Extreme operating temperatures require strong and durable sensors such as high-temperature thermocouple TAF16.
• Presence of complex gas mixtures require accurate analysis of the evolving gas composition. Our Raman Rxn5 analyzer offers reliable in-line spectroscopy.
• Prowirl F 200 is a reliable Vortex flowmeter suitable for high-temperature steam measurement including wet steam detection.

Hydrogen must meet high quality standards depending on the transportation method and end use, especially in fuel cells (ISO 14687:2019). Optical technologies for moisture (H₂O) and oxygen (O₂) measurements offer maintenance-free operation due to their inherent robustness and reliability.

• Very fast response times for identifying process impurities.
• No moving parts, no electrolytes and long-lasting optics enable extremely low maintenance. 
• Easy to install and commission with Heartbeat Technology health monitoring.