Spacecraft Water Recovery System — 2D Flow Diagram

Crew & Feed

Crew size 6

Wastewater collected 8.0 L/person/day

Recovery efficiency η 92%

Time speed 1.0 day/s

Mass Balance

Potable reserve

600 L

Net balance

0.0 L/day

Days elapsed / to depletion

0 d

How it works

A vapor-compression distillation (VCD) unit — the core of ECLSS-class water recovery hardware — boils contaminated wastewater under low pressure, mechanically recompresses the vapor to raise its saturation temperature, and condenses it against the incoming feed so the latent heat is recycled instead of radiated away. Only a fraction η of the feed becomes potable distillate; the rest concentrates into a brine that must be vented or stored.

recovered(t)  = crew · feed · η
consumed(t)   = crew · demand           (demand fixed at 8 L/person/day)
dReserve/dt   = recovered − consumed
brine(t)      = crew · feed · (1 − η)

Because a closed life-support loop only works if what's recovered keeps pace with what's used, the reserve tank drains whenever η·feed falls short of demand — even a 5–8 percentage-point efficiency loss compounds over a multi-month mission into a large resupply mass, which is exactly why real hardware (ISS WRS, Orion) is engineered for 90–98% recovery rather than "good enough." This 2D view adds a scrolling reserve strip-chart alongside the flow schematic so the trend is visible at a glance, not just the instantaneous tank level.

Crew size — scales both the wastewater generated and the potable demand.
Wastewater collected — how much of what the crew uses actually reaches the distillation unit as feed (collection losses lower this).
Recovery efficiency η — the distillation unit's single-pass yield; the dot stream splits into a blue potable branch and a brown brine branch in this ratio.
Filter Fouling Event — knocks η down by 20 points for 5 simulated days, mimicking a membrane-scaling incident, so you can watch the reserve trend reverse and recover.
Drag / scroll on the diagram — pan and zoom the schematic; "Reset view" returns to the default framing.

Reserve: 600 L

Drag to pan · scroll to zoom

Wastewater feed Recovered potable water Concentrated brine