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Hydrogen System – Piping and Instrumentation

Diagram

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Hydrogen System P&ID

Cryostat

HeliumStore

Gas Panel

Venting

Vac. Pumps

Heater/ChillerUnit

HydrogenBottle

H

H H

H

H

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Line Types and Colour Coding

Note: This scheme is based on operating the system with Hydrogen rather than Helium.

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Nomenclature

• HA prefix used throughout to indicate Hydrogen System A

• Pipelines– G or L prefix indicates

whether line will contain gas or liquid during normal operation with cryo-cooler running.

– Pipe size specified according to I.D. or DN standard.

H

H H

H

H

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Nomenclature (2)

• Valves– All uniquely numbered

• PV – Pneumatic Valve

• CV – Control Valve• HV – Hand Valve• BD – Bursting Disc• RV – Relief Valve

– Sized by DN standard– Set pressure shown

for relief valves

H

H H

H

H

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Nomenclature (3)

• Instrumentation– PG/VG –

Pressure/Vacuum Gauge

– LS – Level Sensor– TS – Temperature

Sensor– HD – Hydrogen

Detector– FM – Flow Meter

• VP - Vacuum Pump

H

H H

H

H

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Gas Panel and Hood

Hydride BedBuffer Volume

Extraction Hood

Absorber ReliefValves

Cryostat Relief Valves

Fill/Purge Valves

H

H H

H

H

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Hydride Bed

• Supplier: TREIBACHER INDUSTRIE AG – The nominal figures for the absorption temperature is -10°C and

+20°C for the evolution temperature. • Heat Transfer Medium - Water / glycolMH • Weight: 120 kg• Tank Structure A hull with 7 inter-connected stainless-steel storage

cylinders , each with internal coil for cooling/heating .• Dimensions Ø370 mm × L1500 mm (not including attachments),

horizontal position• Tank Total Weight 260-280 kg• Operating Conditions:

– Charging Gas Component Hydrogen of 99.99% purity – Charging Gas Pressure 1.2-1.7 bar abs– Hydrogen Charging Rate Max 70 NL/min – Discharging Gas Pressure 1.0-7.0 bar abs

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Fill/Purge Valves

• Pneumatically actuated valves• Arrow indicates position on failure

H

H H

H

H

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Valve Types

• Ball Valves– Pneumatically actuated– Spring Return Actuators ensure

valve returns to default position on failure

• Control Valves– Pneumatically Actuated– Large range on throttling– Suitable for use with hydrogen

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Relief Valves

• Tyco (AG Series 90) Relief Valves– Pilot valves – quick acting– 3% tolerance on set

pressure– Closes at 95% of set

pressure– Response time is <0.5s

• BS&B Low Pressure Reverse Buckling Disc– ±5% tolerance on burst

pressure– Vacuum/back pressure

resistant• Hand Valves can be locked off

as necessary

H

H H

H

H

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Instrumentation

• Temperature Sensors– Platinum Resistance– Fast response time (<0.5s)

• Level Sensors– AMI Capacitance Level

Transmitter– Useable with Hydrogen

• Pressure and Vacuum Gauges– Leybold can supply

capacitance vacuum gauges, which are safe for use with hydrogen.

– Explosion proof pressure transducers available from Honeywell

Level SensorsPressure Transducers

Temperature sensors

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Cryostat

H

H H

H

H

Cryocooler

Compressor

Level Sensors

Helium Jacketingon Pipes

Electrical heating ofbase plate

Pre-cooling loops

Pressure Transducers

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Vacuum System

2 Elements

• Purging Pump for H2 system

• Cryostat Vacuum

H

H H

HH

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Vacuum System

• Proposal received from Leybold based on combination of rotary vane and turbo-molecular pumps

– TRIVAC D40B for hydrogen system purging pump (VP1)

– Special Pumpset with active control suggested for cryostat vacuum (VP2)

• D25BCS backing pump

• Turbo-molecular TMP151C to achieve high vacuum (10-3 mbar)

• Both pumps can be operated with purge gas (e.g. He) if pressure rises (indicating a leak)

TRIVAC D40B

TMP151C

TRIVACD25BCS

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Venting

• Hydrogen detectors in extraction hood, vent line and vacuum exhaust• 2 fans provide redundancy in venting from hood• Flame arrestors used throughout• Helium flow in vent line to dilute leaks

H

H H

H

H

Whessoe – Varec Flame Arrestor

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END