Set acceptance criteria before starting
Define feed flow and composition, and permeate and concentrate quality targets. Describe expected variability across shifts, batches, seasons, start-ups and plant washes. Set thresholds for net production, cleaning recovery, outlet quality and availability that would make the project viable.
Document module, area, instruments, sampling method and feed conditions. A uniform laboratory sample may miss fibres or production discharges.
- Log feed, permeate, purge and recirculation flow.
- Measure relevant TSS/TS, total/soluble COD, viscosity, oil, pH and temperature.
- Time-stamp pressures, TMP, electricity and consumables.
Test the whole cycle and final concentration
Start with a stable baseline and move in stages to the target concentration factor. Measure flux and TMP through each cycle, after backwash and after CIP. Flux decline and subsequent recovery separate reversible deposits from persistent loss.
Close water and solids balances to find settling or unrepresentative samples. As viscosity rises, check that pumps, mixing and pipework retain enough margin.
| Outcome | Acceptance question |
|---|---|
| Net flux | Does it include washing and availability? |
| Concentration | Can it still be pumped? |
| Permeate | Does it meet the next use or treatment step? |
| CIP | Does it restore output without material damage? |
Scale with uncertainty
A proposal should state the measured range and design allowance, plus conditions the trial did not represent. A short pilot does not prove seasonality or membrane life. If chemistry, pretreatment or outlet destinations change, revisit the design.
State who will review the pilot record and what decisions follow each failure. If permeate quality fails, first identify the passing component; if flux fails, distinguish reversible deposits from permanent loss. An acceptance report should retain raw data and the assumptions used for scale-up.
Common questions
Is a clean-water trial enough?
It can provide a hydraulic or integrity baseline; it does not reproduce fouling, concentration or net production on real wastewater.