Applications in the hydrogen industry

The aim is to guarantee safety for all applications and all possible levels of skill – from a qualified, trained professional in hydrogen production to an untrained consumer at the refuelling station. 

“Functional safety” is the term used when safety depends on the correct function of a control system. Detection technologies combined with safe control technology play a key role in the safe use of hydrogen for avoiding damage and accidents.

These applications range from hydrogen production in electrolysers or steam reformers and hydrogen handling, for example at hydrogen refuelling stations, through to hydrogen consumption in fuel cells, engines and burners.

Industrial Security describes the protection of production and industrial plants from intentional or unintentional manipulation. As such it deals with the security of control networks in production and industrial plants in factory automation and process control.

A hydrogen-related example would be remote access to a hydrogen production system, to check its status. As soon as this remote connection enables the safety-related part of the system to be controlled or modified, this connection must be protected. Without protection there is the potential for someone to modify the system without permission and potentially create a dangerous state.

With Identification and Access Management (I.A.M.), you can protect your data and employees in equal measure. From user authentication to data and network security – we are happy to advise! 

For hydrogen electrolysers, the standard ISO 22734:2019 Hydrogen generators using water electrolysis – industrial, commercial and residential applications is the reference safety document. This standard contains safety requirements and related testing methods for all the components and materials. 

Safety functions on electrolysers:

• E-STOP
• Voltage monitoring
• Current monitoring
• Leak detection
• Gas detection
• Flame/fire alarm

The detection of gases and flames is mandatory in order to initiate suitable safety measures such as ventilation or to prevent access to this area. 

The lack of a constant current source can pose an additional safety problem (cross-over phenomenon). For this reason, a fault in the electrical part – voltage or current – can lead to a possible explosion risk.

The establishment and operation of a hydrogen refuelling station (HRS) are approved by the local authorities and are subject to the oversight of national or regional legislation. The standard ISO 19880-1:2020 Gaseous hydrogen - Fuelling stations - Part 1: General requirements includes a methodology for guaranteeing the safety of refuelling stations. This standard requires measures to reduce the risk of fire and explosion. A risk assessment of the whole station is mandatory.

An HRS consists of high-pressure components such as compressors, valves, pipes and pressure accumulators. Add to that the cooling system and the hydrogen supply area, for example refuelling dispensers with pressures of 350 or 700 bar, and temperatures of the gas delivered by the dispenser down to -40 degrees Celsius (233.15 Kelvin).

Safety functions on hydrogen refuelling stations:

• E-STOP
• Leak detection
• Gas detection
• Flame/fire alarm
• Pressure monitoring, gradient monitoring
• Temperature monitoring, gradient monitoring

The standard ISO 16110-1:2007 Hydrogen generators using fuel processing technologies - Part 1: Safety explains all the significant hazards (EMC, electrical aspects, high-pressure aspects, prevention of explosions, etc.) regarding the safety of hydrogen production from fossil fuels such as steam reforming.

Steam reforming is currently the most important method for the generation of hydrogen from water and carbon-based energy carriers. Natural gas is the most important raw material today, but methanol, biogas or biomass can also be used as the starting material. This process requires high temperatures, which are achieved using gas burners. 

Safety functions:

• E-STOP
• Burner management
• Leak detection
• Gas detection
• Flame/fire alarm
• Pressure monitoring
• Temperature monitoring

The safe controllers PNOZmulti 2 or PSS 4000 can take control of the burner management system and also monitor the safety of the process. For example, temperatures and high pressures are monitored and controlled safely to avoid any unexpected situations that can lead to a hazard.

When using 100 % hydrogen or mixtures of gaseous hydrocarbon fuels, such as natural gas, with hydrogen as a fuel in gas burners, the existing standards for burners with gaseous fuels apply.

These standards apply, for example:

• EN 298
• IEC/UL 60730-2-5 for burner control
• EN 676 for gas burners 
• ISO 13577 for industrial furnaces (area of gaseous fuels) 

These standards differentiate between gaseous, liquid and solid fuels, but there is no differentiation based on specific gases within the group of gaseous fuels. For this reason, the existing standards also apply to hydrogen.

The PNOZmulti 2 burner management system is 100 % ready for use for burning hydrogen or mixtures of gaseous hydrocarbon fuels.