Water parameter
Showing 1–6 of 6
- 6SDI15dimensionlessWater parameter
Silt density index
An index of the particulate fouling potential of RO feed water, from the rate at which a 0.45 µm filter plugs at constant pressure.
StandardisedTypical: below 5, preferably below 3 (RO feed)Level 3 · Monitoring & analyticsOpen record - 5SR%Water parameter
Salt rejection
The fraction of dissolved salt kept out of the permeate: one minus the ratio of permeate to feed concentration.
EstablishedTypical: 99.6–99.8% (seawater elements under standard test conditions)Level 3 · Monitoring & analyticsOpen record - 4R%Water parameter
Recovery
Permeate flow as a percentage of feed flow. Higher recovery concentrates the brine and raises scaling risk at the tail of the system.
EstablishedTypical: 35–50% (seawater RO); 75–85% (brackish RO)Level 3 · Monitoring & analyticsOpen record - 3Qpm³/hWater parameter
Permeate flow
The flow of product water through the membranes; compared with the design value only after normalization for temperature and pressure.
EstablishedLevel 3 · Monitoring & analyticsOpen record - 2ECµS/cmWater parameter
Conductivity
A solution’s ability to carry electric current, proportional to its dissolved ions. Measured continuously on RO feed and permeate as the fastest indicator of salt rejection.
StandardisedTypical: about 53,000 µS/cm (seawater, 35 g/L); 50–800 µS/cm (drinking water)Level 3 · Monitoring & analyticsOpen record - 1PbarWater parameter
Feed pressure
The pressure applied to the feed side of the membrane; the net driving pressure is what remains after subtracting the osmotic pressure difference and losses.
EstablishedTypical: 55–70 bar (seawater RO); 8–25 bar (brackish RO)Level 3 · Monitoring & analyticsOpen record