20 kL Cryogenic Liquid Medical Oxygen Vertical Storage Tank for Kokrajhar Medical College and Hospital, Assam — rated to 20,000 L / 17 bar.

Introduction

Cryogenic liquid oxygen (LOX) storage tanks are critical infrastructure for industries ranging from healthcare to semiconductor fabrication, where uninterrupted, high-purity oxygen supply is essential. Unlike conventional pressure vessels, these tanks maintain inner temperatures as low as −183°C through a double-walled, vacuum-insulated design, minimizing heat ingress and boil-off losses. The CRYO-V-Oxygen employs a stainless-steel inner vessel housed within a carbon-steel outer shell, with a perlite-filled annulus under high vacuum — a configuration proven reliable in industrial and medical settings. Modern tanks like these not only ensure safety and regulatory compliance but also optimize operational costs by limiting daily losses to under 0.45% of stored volume.

Technical specification

• Nominal capacity: 20,000 L ±5%.
• Inner vessel material: Austenitic SS-304 (X5 CrNi 18-10).
• Outer shell material: Carbon Steel S355J2, epoxy-coated for corrosion resistance.
• Design codes: EN 13458-2:2002 + Annex C; ASME VIII-1; PED 2014/68/EU.
• Working pressure (inner): up to 17 bar gauge.
• Design temperatures: inner −196°C to +40°C; outer −20°C to +55°C.
• Boil-off rate (NER): ≤0.45%/day (perlite insulation under vacuum).
• Annular vacuum: ≤100 µm Hg (warm).
• Insulation medium: perlite powder; optional upgrade to 3M Glass Bubbles for up to 35% lower boil-off.
• Relief devices: dual spring-loaded relief valves, dual burst discs, manual selector valve.

Key features

• Vacuum-insulated double wall: high-vacuum annulus packed with perlite ensures minimal heat leakage and consistent thermal performance.
• Pressure-building coil: star-finned coil immersed in liquid for rapid vapor generation, enabling stable delivery pressure without external vaporizers.
• Advanced safety suite: two independent relief valves and burst discs protect against overpressure; full-bore manual isolation cock simplifies maintenance.
• Integrated sampling port: corrosion-resistant port for liquid sampling and purity verification, critical in semiconductor and medical applications.
• Portable vacuum monitoring: thermocouple sensor and vacuum gauge with isolation valve allow on-line annulus integrity checks.

Operating parameters

• Filling: top and bottom fill connections accommodate differential-pressure and pump-assisted filling, reducing transfer time.
• Withdrawal: dedicated liquid outlet with check valve; gas draw-off via pressure-building coil with integrated filter and regulator ensures contaminant-free vapor delivery.
• Pressurization range: user-adjustable from 2 bar up to design limit of 17 bar, supporting varied downstream process requirements.
• Evacuation & purge: annulus evacuation port with isolation valve for initial pump-down; optional dry-gas purge maintains insulation dryness and performance.

Thermal insulation & performance

Perlite-filled, vacuum-insulated annulus provides a cost-effective barrier against ambient heat, delivering boil-off rates below 0.45%/day under steady-state conditions. Emerging insulation media — such as engineered glass bubbles — can further reduce heat ingress by up to 35%, extending hold times and lowering operational costs. Periodic thermal cycling tests validate insulation integrity, ensuring no settlement or compaction that could degrade performance over years of service.

Safety & pressure control

Built to PESO and international pressure-vessel directives, the tank includes:

• Dual redundancy relief: two spring-loaded safety valves sized to API standards, plus backup burst discs.
• Selector valve: manual full-bore valve to isolate relief network for safe maintenance without tank depressurization.
• Leak-tight piping: stainless-steel long-stem globe valves and orbital-welded connections minimize leak risk.
• Third-party certification: factory acceptance and periodic inspection by CCOE/PESO-approved agencies guarantee compliance.

Instrumentation & connections

• Level measurement: differential-pressure transmitter with three-valve manifold and liquid level gauge for continuous monitoring.
• Pressure indication: local Bourdon-tube gauge plus digital transducer option for SCADA integration.
• Vacuum sensor: thermocouple-type vacuum gauge with isolation and calibration ports.
• Process integration: all connections flanged per EN 1092; P&ID and 3-D CAD models supplied for site coordination.

Ancillaries & site requirements

• Foundation: concrete pad with anchor bolts, footprint template provided upon order.
• Utilities: 3-phase power for vacuum pump; dry nitrogen purge supply for annulus; drain for condensate collection.
• Documentation: comprehensive manuals, P&ID, FAT reports, and certificates delivered in both digital and hard-copy formats.

Conclusion

The CRYO-V-Oxygen tank represents a turnkey solution for high-capacity LOX storage, combining industry-leading insulation, advanced safety features, and versatile process interfaces. Whether for critical medical support, precision semiconductor processes, or demanding industrial applications, this tank ensures reliable, low-loss oxygen supply while adhering to the strictest global standards. For turnkey installation and lifecycle support, Neometrix Engineering delivers expert project management and after-sales service.