Volatile Product Storage
Dedicated High-Pressure Composite Vessels for Non-RFC Volatiles
Volatile Product Storage comprises independent Type-IV and Type-V composite overwrap vessels that store refined gases—including nitrogen, helium, helium-3, and carbon dioxide—at 300 bar to provide buffered reserves for life support, fusion research, and industrial feedstocks. Operating on the Moon requires siting the 0.5-cubic-meter tanks within stable-temperature shaded zones to prevent composite fatigue induced by severe lunar thermal cycling, alongside regolith berms and Whipple bumpers for micrometeoroid shielding. Constructed with stainless-steel liners, T800 carbon-fiber overwraps, and capacitance-based mass gauges, these tank assemblies limit annual leakage below 0.5 percent across a 25-year operational lifetime during decade-scale accumulation.
Set of dedicated high-pressure composite vessels storing recovered volatiles (N2, He, He-3, CO, CO2) separate from the RFC reactant tanks, providing buffered inventories for life-support contingencies, future fusion research, and chemical-process feedstocks.
Purpose
Capture and preserve the long-term volatile value of all ISRU processing — even if some species (He-3) take decades to accumulate enough for meaningful use, the storage exists from day one so nothing is wasted.
Context
Receives purified species from L3-ISR-VOL-SEP; provides buffered supply to potential consumers including L1-WMS (N2/He life support), future Ark expansions, and Earth-export reserves. Pressure regulation, mass gauging, and slow-leak detection.
Principles
- ▸Composite Type-IV/V tanks at 200-300 bar for gaseous storage of He, N2, CO, CO2
- ▸Density at 300 bar: He ~50 kg/m³, N2 ~330 kg/m³, CO2 (supercritical) ~700 kg/m³
- ▸Independent tanks per species to prevent cross-contamination
- ▸Mass gauge for accurate inventory tracking over decade-scale accumulation
- ▸Slow-leak detection via pressure decay analysis — important for low-density He which permeates polymers easily
- ▸Mounted in shielded location to protect against MMOD
Typical implementations
- ▸ISS gas storage tanks (N2, O2, atmospheric replenishment)
- ▸Apollo high-pressure He and N2 tanks heritage
- ▸Industrial CGA high-pressure cylinder standards
- ▸ESA Aurora program gas storage concepts
- ▸ULA ACES helium storage for stage pressurization heritage
Lunar considerations
- ▸Lunar vacuum allows simpler containment (no atmospheric leakage)
- ▸He-3 is high-value but may accumulate slowly — design for decade-scale slow fill
- ▸MMOD shielding via regolith berm + Whipple bumper
- ▸Thermal cycling drives composite-tank fatigue — siting in stable-temperature shaded area preferred
- ▸Long-term He containment requires all-metal tank (Type V) — He permeates polymers slowly but measurably over decades
- ▸Robotic gas-line quick-disconnects for L1-MNT replacement of vessels
Specifications
Functional
| primary function | Long-term high-pressure storage of recovered volatile species |
| inputs | Purified gas streams from L3-ISR-VOL-SEP, Compressor power to fill at 300 bar |
| outputs | Regulated supply to consumers (L1-WMS, etc.) at low pressure (~5 bar), Inventory and pressure telemetry per tank |
| tank count species | 4 |
| operating pressure bar | 300 |
| burst pressure bar | 660 |
| per tank capacity m3 | 0.5 |
| design lifetime years | 25 |
| annual leak rate percent max | 0.5 |
| species supported | N2, He, He-3, CO2 |
Physical
| mass kg per tank | 25 |
| total mass kg | 100 |
| dimensions per tank | 1.0 m × 0.6 m diameter (composite cylinder) |
| materials | Stainless steel inner liner (Type IV) or all-stainless (Type V for He), T800 carbon-fiber-epoxy composite overwrap, Stainless 316L valves and regulators, PTFE-lined metal seals, Outer protective shell (anti-MMOD), Mass gauge: capacitance probe + pressure transducer |
| operating temperature c | -180, 100 |
| ultimate load g | 6 |
Operational
| power consumption w | 0 |
| thermal range c | -180, 100 |
| lifetime years | 25 |
| mtbf hours | 400000 |
Interfaces
Provides
- Regulated N2 / He for life-support augmentation
- Per-tank inventory and pressure
- CO/CO2 for downstream chemistry (Sabatier reactor, etc.)
Requires
- Purified species streams
- Compressor power during fill (~500 W intermittent)
- MMOD shielding (regolith berm)
Cite this entry
Lunar Ark Codex. "Volatile Product Storage" (L3-ISR-VOL-STORE). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-ISR-VOL-STORE
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.