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Nitrogen, Process Air and Valves for Hydrogen and Clean Energy
A hydrogen plant is more than its electrolyser and hydrogen compressor. Around them sits the equipment that keeps the plant safe and running: nitrogen to purge each line before start-up, clean instrument air to move each valve, filters holding the gas to specification, and hydraulics and hose that must stay leak-tight inside a hazardous zone.
Control Gear Group, specialists in compressed air and industrial equipment, supplies, installs and services that equipment. We’re fluid power specialists, founded in 1973 and based in Treforest, Pontypridd, with on-site service across South Wales and the South West and supply UK-wide.
What Does a Hydrogen Site Need From Its Utilities Supplier?
Safety in hazardous areas, the right purity, leak tightness, reliable new plant and as few utility suppliers as possible.
Safety starts with your hazardous area classification. Under the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR), employers must classify the areas where explosive atmospheres may occur and keep ignition sources out of them, as HSE’s guidance on DSEAR explains. A valve or hose that is fine in a workshop may be unacceptable a few metres away in a Zone 1 area.
Hydrogen is the smallest molecule there is, so it escapes through joints that would hold compressed air. And because the utilities depend on each other, a fault in the instrument air or nitrogen can stop an electrolyser that is itself working perfectly.
50+
years of industrial equipment experience
Nitrogen, Instrument Air, Hydrogen Compressors and Festo Automation
Lines and vessels on a hydrogen site are purged with nitrogen before hydrogen goes in, after shutdown and before anyone breaks into the system for maintenance. HSE calls inerting “a very effective method of explosion prevention” and notes that inert gas may be generated on site in its technical guidance on inerting.
Nitrogen for Purging
Nitrogen brings its own hazard. HSE names asphyxiation, particularly in confined spaces, as a major risk of inerting, so generator vents need to discharge somewhere safe.
We supply, install and service nitrogen generators from Atlas Copco, one of the world’s largest compressed air manufacturers, as one of its longest established Premier Distributors in the UK. Membrane and PSA (pressure swing adsorption) generators reach 99.999% purity. Our industrial gases range covers the options.
The same HSE guidance says reliability of the inert gas supply “is of vital importance”. We size the generator and buffer vessel to your purge volumes, can add a back-up supply, and fit SMARTLINK remote monitoring so a fault shows before the next purge.
Oil-Free Instrument Air
Every actuator and positioner on an electrolyser skid runs on instrument air. Wet or oily air makes valves stick, and a shutdown valve that sticks has failed at the one moment it matters.
We supply, install, service and repair Atlas Copco compressors, dryers and filters, including oil-free machines for ISO 8573-1 Class 0 air. ISO 8573-1 is the international standard that classifies compressed air purity by particles, water and oil, and Class 0 is its most stringent oil class. Our compressed air division also runs leak detection and energy audits.
Atlas Copco Hydrogen Compressors
Atlas Copco also builds hydrogen compressors. Its H2P range is an oil-free reciprocating design made to take gas directly from an electrolyser, keeping oil out of the product. We supply from that range and specify the utilities around it.
Hydrogen sits alongside power generation in our energy work, and our page on compressed air for the energy sector shows how we support power and energy sites.
Festo Balance of Plant
Festo, the German automation manufacturer, has a hydrogen range built around electrolyser balance of plant: remote I/O, valve terminals, positioners, proportional valves, process valves certified to IEC 61508 SIL and control cabinets for potentially explosive atmospheres.
As an official Festo partner, we supply from that hydrogen range. Our engineers service and repair Festo valves, cylinders and air preparation, and retrofit older pneumatic control to valve terminals, through our Festo pneumatics and automation team.
We’re also an authorised distributor for IMI Norgren, the pneumatic controls manufacturer, whose proportional valves come with ATEX-approved options for zoned areas.
Process Valves and Actuators for Hydrogen Service
Stem and body sealing, materials that resist hydrogen embrittlement and suitability for the zone all come before price. We supply:
- Ball valves with fire-safe testing and blowout-proof stems, including trunnion-mounted and top-entry designs
- Butterfly valves, including high-performance and triple-offset designs
- Gate, globe and check valves for isolation, flow control and reverse-flow protection
- Actuators matched to the valve and the duty
Process valves are a growing part of Control Gear, with a dedicated process team being built around them. We’ll ask for your line list, pressures, temperatures and zones before we quote. Our process valves and actuators page lists the full range.
Where Each Division Fits on a Hydrogen Site
Control Gear supplies on-site nitrogen, oil-free air, process valves, Festo automation, HYDAC and Pall filtration, hydraulics and hose, and services them under one team.
- Purge and inerting: Atlas Copco PSA and membrane nitrogen generators, back-up supply, SMARTLINK monitoring
- Instrument and process air: oil-free Atlas Copco compressors, dryers and filters for ISO 8573-1 Class 0 air
- Hydrogen compression: Atlas Copco’s oil-free H2P hydrogen compressor range
- Process pipework: ball, butterfly, gate, globe and check valves with actuators
- Electrolyser balance of plant: Festo valve terminals, positioners and SIL-rated valves, IMI Norgren ATEX options
- Gas and fluid purity: HYDAC hydrogen drying and filtration, Pall and 3M Cuno process filtration
- Hydraulics and cooling: HYDAC hydraulics, accumulator recertification, Atlas Copco chillers
- Transfer and connections: ATEX-compliant hose, stainless metallic hose, tested assemblies
Gas Purity, Filtration and Hydraulics
Raw hydrogen from an electrolyser carries water and oxygen that have to come out before it meets its purity specification. HYDAC, the German hydraulics and filtration manufacturer, makes hydrogen drying, gas filtration and balance-of-plant sensors for electrolysers. We’re a HYDAC partner for its entire portfolio and supply from that range.
We’ve been an authorised distributor for Pall, the industrial filtration manufacturer, for well over 20 years, and we’re official distributors for 3M Cuno. Our industrial and process filtration team covers process water, fuels and chemicals, with condition monitoring, sampling and analysis.
Hydraulics turn up in electrolyser stack clamping and compressor drive units. Our engineers:
- build and commission hydraulic power units
- repair pumps, valves and cylinders
- recertify hydraulic accumulators
Oil sampling catches contamination early, and our HYDAC hydraulics and filtration team supplies the filter elements, accumulators, sensors and fluid care units that keep the oil clean. For electrolyser and compressor cooling, our F-Gas certified engineers supply and service Atlas Copco chillers.
Hose, Metallic Hose and Fittings
Hose is where a leak-tight system most often stops being leak-tight. Our hose team is certified by the British Fluid Power Association and makes up hydraulic and industrial hose assemblies in-house, including ATEX-compliant hose, with pressure testing and certification.
Hydrogen sites share many ATEX duties with fuel handling, covered on our oil and gas industry page.
For high pressure, high temperature or corrosive duties, our stainless metallic hose assemblies meet Class 1 of EN ISO 10380 and the Pressure Equipment Directive 2014/68/EU. On the hydrogen side, each hose and fitting must carry its manufacturer’s rating for hydrogen at your working pressure, and we check that rating before we make up an assembly.
Pressure Systems and Compliance Support
Under the Pressure Systems Safety Regulations 2000, a system holding compressed gas above 0.5 bar must not be operated until a written scheme of examination, drawn up or certified by a competent person, is in place.
Written Schemes and Leak Detection
Written Schemes and Leak Detection
We prepare Written Schemes of Examination for compressed air and nitrogen plant and carry out leak detection surveys. We hold ISO 9001, ISO 14001 and ISO 45001 certification.
Major Accident Thresholds for Hydrogen
Major Accident Thresholds for Hydrogen
Larger hydrogen stores fall under a further regime. The Control of Major Accident Hazards Regulations 2015 name hydrogen as a dangerous substance, with a lower-tier threshold of 5 tonnes and an upper-tier threshold of 50 tonnes.
Where Our Written Schemes Stop
Where Our Written Schemes Stop
One limit is worth being clear about. Our written schemes cover the air and nitrogen plant we supply and service. The hydrogen pressure system itself, and the zoning under DSEAR, belong to your site’s own competent person and risk assessment, so if a plant change has moved a zone boundary, sort the classification before the equipment schedule.
Talk to Control Gear About Your Hydrogen Project
The government’s first Hydrogen Allocation Round named 11 successful projects totalling 125 MW. Two are in Wales, HyBont (5.2 MW) and West Wales Hydrogen (14.2 MW), and one is in the South West, Langage Green Hydrogen (7.0 MW), according to the Department for Energy Security and Net Zero’s HAR1 list.
Sites like these need the purge nitrogen, instrument air and zoned equipment described above, and our engineers already work on site across both regions.
If you’re specifying a new hydrogen plant or pilot unit, send us your purge volumes and nitrogen purity, instrument air demand, valve line list and zone classification for each area. Our Treforest team will come back with matched options for the nitrogen generator and back-up, air treatment, valves, Festo automation, filtration and hose, specified together. Call 01443 843126 or use the contact form to arrange a site visit.
Get in touch
Contact Control Gear today
Tell us about your site and we’ll come back with the right service, audit or system recommendation.
- Visit us Heol Groeswen, Treforest Industrial Estate, Pontypridd, Rhondda Cynon Taff, CF37 5YF
- Call us 01443 843126
- Email us enquiries@control-gear.com
Mon–Fri · 09:00–17:00
24/7 emergency call-out available