Rare Gas Two Heads 10 Bar Oil Free Hydrogen And H2S Diaphragm Boost Compressor

A two-head oil-free diaphragm boost compressor rated to 10 bar is designed for laboratories, pilot plants, specialty-gas filling rooms, petrochemical sampling systems, biogas and sour-gas research, fuel-cell test benches and rare-gas recovery skids that need to raise hydrogen, hydrogen sulfide or noble/rare gases from low suction to stable medium pressure without oil contamination. The metal diaphragm principle seals the process gas inside a static wetted cavity separated from hydraulic oil, crankcase lubricant and ambient air, so the package is suitable for toxic H2S, flammable hydrogen and high-purity rare gases when the two heads, materials, seals and safety systems are selected for each medium .

For a 10 bar discharge, the machine is usually arranged as a single-stage or low-ratio two-stage booster. "Two heads" may mean two parallel compression heads for higher flow, two separate heads for different gases, or a duplex redundancy layout for continuous rare-gas/H2/H2S service. Because hydrogen and H2S have very different hazard profiles, a single shared wetted path for both is not recommended unless the whole train is fully requalified, cleaned, purged and validated for the exact mixture.

Reference Specification Table

Diaphragm boosters are documented for hydrogen, H2S, helium, argon, nitrogen and many corrosive/toxic gases, with oil-free separation from hydraulic oil and discharge capability from low pressure up to much higher pressures in multi-stage designs . For a 10 bar target, the value is stable, contamination-free boosting rather than extreme high-pressure filling.

Why Two Heads For H2, H2S And Rare Gas

A two-head layout gives several operating models:

• Parallel boosting: both heads compress the same gas to increase Nm³/h at 10 bar without oversizing one crankbox.

• Dual-gas separation: head A handles hydrogen or rare gas, head B handles H2S or sour mixture. Each head has independent wetted materials, valves, relief and purge so cross-contamination is avoided.

• Redundancy: one head runs while the second is on standby for laboratories or process sampling that cannot tolerate downtime.

• Load sharing with VFD: two heads modulate by demand, improving part-load efficiency for variable hydrogen recovery or fluctuating H2S sampling.

• Thermal control: splitting flow across two heads reduces per-head heat rise, useful when H2S moisture or hydrogen purity makes discharge-temperature control critical.

For 10 bar boost from low suction, a single head may be enough for small flow. Two heads are specified when flow, redundancy, gas segregation or future expansion justify the larger frame.

Hydrogen Considerations

Hydrogen is flammable, very light and prone to leakage through dynamic seals. A metal diaphragm booster is preferred because the gas chamber is static, oil-free and easy to leak-test.

• Oil-free path: hydrogen never contacts crankcase oil or piston lubricant, protecting fuel-cell, analyzer, semiconductor and rare-gas recovery purity .

• Leak tightness: diaphragm packages use welded/metal-clamped gas paths; published hydrogen diaphragm designs quote very low leak rates, with helium leak-test thresholds commonly around 1×10⁻⁶ Pa·m³/s or tighter depending on joint and seal design .

• Embrittlement control: at 10 bar the risk is lower than at 350-900 bar, but head, bolts, diaphragms and springs should use hydrogen-compatible alloys and controlled hardness. 316L, low-carbon stainless and selected Inconel/precipitation-hardening alloys are common; very high-strength steels need review .

• Seals: PTFE, PEEK, Kalrez or metal seals by temperature and purity; nitrile and unknown elastomers are not recommended for hydrogen wetted service.

• Safety: H2 gas detection, ventilation, relief valves,自动 emergency shutdown, explosion-protected electrical equipment and purge prior to startup.

• Purity: for rare-gas/hydrogen mixtures or fuel-cell test, specify 99.99% to 99.9999% train validation including piping, tanks, filters and dryers.

H2S And Sour-Gas Considerations

Hydrogen sulfide is toxic, flammable and corrosive, especially with moisture. A 10 bar H2S booster still requires full sour-service design.

• Material selection: avoid standard high-strength carbon steel in wetted sour service. Use 316L for many dry/low-chloride duties, but for wet/sour H2S consider Hastelloy C-276, Inconel grades or qualified corrosion-resistant alloys. Diaphragm plates may use 316L with controlled hardness, or Inconel where sulfide stress cracking and fatigue require it .

• Standards awareness: NACE MR0175 / ISO 15156 governs sulfide stress cracking and material hardness limits for sour service; final applicability depends on H2S partial pressure, water, chlorides, pH and code. Do not specify "NACE-compliant" without the exact gas composition and partial pressures .

• Moisture control: wet H2S forms sulfuric/acidity and accelerates pitting; use drying, stainless/alternate-alloy wetted path, water cooling with controlled discharge temperature and regular corrosion inspection.

• Seals: PTFE, graphite and qualified polymer seals; ordinary nitrile rubber can harden/crack in H2S and is not recommended for wetted gas contact .

• Safety system: H2S detectors, audible/visual alarm, ventilation interlock, emergency isolation, relief to safe location, neutralization/scrubber for small releases, Ex d/IIC electrical equipment by zone.

• Diaphragm leak cavity: multilayer diaphragms with intermediate cavity detect primary diaphragm failure and prevent gas/oil mixing before shutdown .

Rare / Noble Gas Considerations

Rare gases such as helium, neon, argon, krypton and xenon are usually non-toxic but require purity, low leakage and contamination control.

• Helium: low molecular weight, expensive, leaks easily; use metal diaphragm, welded path, metal/PTFE/Kalrez seals, helium leak test and recovery buffer.

• Argon/Neon/Krypton/Xenon: specify electropolished 316L or Inconel, particle filtration, moisture and oxygen control where applicable, and validated ISO 8573-style or customer purity class.

• Mixed rare-gas plus H2 or H2S: treat as special mixture. Require full component analysis, reactivity, toxicity, moisture and permissible impurities before using one booster. Where H2S is present even in trace quantity, the machine must follow sour-service safety rather than pure rare-gas practice.

Two-Head System Configuration

Sizing Method For 10 Bar Boost

1. Define each gas exactly: pure H2, pure H2S, rare gas, or mixture with full mole fraction, moisture, O2, hydrocarbons, particulates and impurities.

2. State suction pressure range, not only average. If supply decays from cylinders or bags, add buffer tank and regulator; unstable suction shortens diaphragm life.

3. State discharge pressure and allowable control band. At 10 bar, single-stage diaphragm is often sufficient, but two-stage may be used for high suction ratio, heat control or future higher pressure.

4. Convert required flow to Nm³/h at suction temperature and pressure. Diaphragm selection uses normal volume, not discharge free volume alone.

5. Choose head count: single head for small flow; two parallel heads for higher Nm³/h; two segregated heads for different gases; duplex for redundancy.

6. Select materials by gas: 316L/Inconel for H2 and rare gas; Hastelloy/Inconel/316L with NACE/ISO 15156 review for H2S; PTFE/PEEK/graphite/metal seals by temperature and chemical compatibility.

7. Select cooling: air for small 10 bar lab boosters; water for higher flow, H2S sour duty, two-head heat load or strict temperature control.

8. Add safety system: H2 detectors and relief for hydrogen; H2S detectors, ventilation, scrubber/flare and Ex controls for sulfide; rare-gas purity monitoring, leak test and isolation valves.

9. Confirm motor, voltage and control: VFD for variable boost; Ex-rated motor and panel for flammable/toxic area; PLC with suction/discharge pressure, temperature, flow, diaphragm-leak alarm and remote stop.

10. Request factory performance test on the actual gas at specified suction, 10 bar discharge, cooling condition and purity acceptance.

Material Selection Guide

These selections follow general diaphragm guidance for corrosive, toxic, flammable and high-purity service; final alloy must be confirmed against H2S partial pressure, moisture, chlorides, oxygen, rare-gas purity and 10 bar thermal/mechanical duty.

Safety And Compliance Features

• Oil-free separation: metal diaphragm prevents hydraulic oil entering hydrogen, H2S or rare-gas stream .

• Overpressure protection: relief valve on each head/outlet manifold, plus burst disk where design requires; 10 bar skids still need staged relief if suction can spike.

• Diaphragm-failure detection: intermediate cavity pressure/temperature alarm; automatic unload or shutdown on primary diaphragm breach .

• Hydrogen safety: gas detection, ventilation permissive, explosion-protected motors/controls, static grounding, purging and ISO 19880-3/NFPA 2 awareness for fuel-cell/refueling contexts .

• H2S safety: toxic-gas detection, audible/visual alarm, emergency isolation, ventilation interlock, relief to safe location, neutralization/scrubber interface and trained response procedure .

• Rare-gas safety: oxygen/impurity monitoring where relevant, confined-space ventilation, non-reactive material validation and leak-test records.

• Quality/system standards: ISO 9001 manufacturer system; pressure-equipment compliance per destination such as ASME or PED; material certificates, weld procedure, hydrostatic/pneumatic test and gas-specific leak test.

• Electrical: Ex d/IIC or appropriate ATEX/IECEx rating for hydrogen/H2S classified areas; non-spark ventilation controls for H2S rooms.

Maintenance Program

Diaphragm life depends on pressure ratio, suction stability, temperature, material finish and cyclic speed. At 10 bar the ratios are moderate, but H2S corrosion, hydrogen purity requirements and two-head duty cycles still require scheduled inspection rather than run-to-failure.

Frequently Asked Questions

Can one two-head diaphragm booster handle hydrogen and H2S at the same time?

Only with a fully validated single mixture path. Hydrogen and H2S have different flammability, toxicity and corrosion risks. For most plants, specify two independent heads: one for H2/rare gas, one for H2S sour service. This avoids cross-contamination, simplifies material selection and improves safety.

Is 10 bar too low for a diaphragm booster?

No. Diaphragm boosters are used from very low suction to high pressure; 10 bar is a moderate discharge point suitable for sample boosting, low-pressure filling, process feed, lab supply and rare-gas transfer. A two-head design at 10 bar is often chosen for flow, redundancy or gas segregation rather than for maximum pressure.

What material is best for H2S at 10 bar?

For dry, low-impurity H2S, 316L may be acceptable after full compatibility review. For wet sour service, Hastelloy C-276, Inconel or other nickel-based alloys are commonly recommended, with NACE MR0175/ISO 15156 review of partial pressure, moisture, chlorides and hardness . Final alloy depends on gas analysis, not only on 10 bar pressure.

Why use diaphragm instead of piston for hydrogen?

Piston boosters use dynamic seals and often lubrication; hydrogen can leak at small molecular scale and oil can contaminate fuel-cell or rare-gas applications. Diaphragm boosters provide static oil-free compression, lower fugitive-emission points and better purity control .

What flow can a two-head 10 bar booster deliver?

It depends on head size, stroke, speed, suction pressure and gas density. Small lab hydrogen/rare-gas units may handle 2-100 Nm³/h per combined heads; industrial H2S/hydrogen boosters can be larger. Request factory Nm³/h at actual suction pressure, 10 bar discharge, gas composition and cooling condition.

Do rare gases need special leak testing?

Yes. Helium and light rare gases require helium mass-spectrometer or calibrated helium leak testing of welded joints, head clamps, valves and instruments. Specify acceptable leak rate, test pressure and retest interval.

What safety system is required for H2S and H2 together?

Separate detection for combustible hydrogen and toxic H2S, classified electrical equipment, ventilation permissive, automated isolation, relief to safe location, H2S scrubber/neutralization interface, diaphragm-leak alarm and PLC emergency shutdown. Do not rely on a single gas sensor for mixed hazards.

Should the two heads be VFD-controlled?

For variable suction, recovery from cylinders, fluctuating lab demand or mixed hydrogen/rare-gas duty, VFD control improves pressure stability and reduces unloaded energy. For steady constant-flow 10 bar boost, fixed-speed two-head packages can be simpler, but VFD is advantageous when demand changes.

What should be requested from suppliers for quotation?

Gas exact composition for each head, suction pressure range, suction temperature, target 10 bar discharge, Nm³/h flow, allowable control band, cooling air/water data, purity specification, material requirement, H2S partial pressure/moisture/chlorides, rare-gas ISO purity class, Ex zone, H2S/H2 detection requirements, relief/scubber interface, voltage/frequency, control system, leak-test method, documentation and onsite commissioning.

A rare-gas two-head 10 bar oil-free diaphragm boost compressor should be specified as segregated or fully validated mixed-gas duty: hydrogen and rare-gas heads with electropolished 316L/Inconel, metal/PTFE/Kalrez sealing and helium leak-test; H2S head with sour-service alloys, multilayer leak-cavity diaphragm, H2S detection and scrubber-ready relief; centralized PLC control with VFD, independent head protection and 10 bar rated safety devices. With correct materials, two-head configuration and oil-free diaphragm isolation, the package provides stable, contamination-free boosting for hydrogen recovery, sour-gas sampling, rare-gas filling and laboratory process air without lubricating the gas stream.