Training material only. Values and process guidance must be checked against the actual plant design, local discharge permit, laboratory results and safety procedures.
01 — Paper mill wastewater journey
Fiber fines, ink, plastics and contaminants may enter the wastewater system.
Poor retention increases fiber and filler losses, TSS and DAF sludge loading.
Starch loss raises biodegradable COD and potential aeration oxygen demand.
Sudden pH or chemical shocks can inhibit biological treatment.
Typical stages: screening → equalization → coagulation/flocculation → DAF or primary settling → biological treatment → secondary clarification → filtration or permitted discharge. Actual arrangements differ by mill.
02 — Detailed equipment
Explore twelve equipment systems with translated operating principles, components, troubleshooting, safety and calculations.
03 — Engineering calculators
Quick estimates for COD/TSS removal, pollutant load and hydraulic retention time. These are not design approvals.
Enter values and calculate.
04 — Troubleshooting
High TSS after DAF
Check inlet load, jar tests, coagulant/polymer preparation, recycle ratio, saturation pressure, bubble distribution and skimmer condition. Verify using inlet/outlet samples before adjusting operation.
Low dissolved oxygen in aeration
Compare actual DO with loading, blower air flow, pressure and diffuser fouling. Evaluate sensor calibration and process shock.
Secondary clarifier sludge washout
Review hydraulic loading, sludge blanket, SVI, RAS/WAS balance and filamentous bulking.
High COD after treatment
Trace starch loss, cleaning discharges, biological inhibition, short-circuiting and sampling errors.
05 — Laboratory and operating log
Track flow, pH, COD, BOD, TSS, DO, MLSS and sludge settling. Collect representative samples and follow validated test methods. Trend readings rather than relying on one sample.
Open the local lab log and CSV reports06 — Virtual ETP operator
Use the educational dashboard to explore how flow, COD, TSS, DAF removal and oxygen supply affect estimated loading. This is not a calibrated SCADA model.
Open the training simulator07 — Paper mill water balance
Record fresh-water intake, process reuse, white-water recirculation, evaporation, product moisture and wastewater discharge. Check conservation of mass and avoid double-counting recycle flows.
Simple balance: intake + imported water − wastewater discharge − evaporation − product moisture − other losses = change in storage (consistent units).
08 — Technology comparison
DAF is effective for floatable fiber-rich solids; settling is appropriate for dense settleable solids.
Biological options differ in biomass retention, space, effluent quality, energy and maintenance.
Reuse requires fit-for-purpose quality; permitted discharge limits are site-specific.
09 — Operation and safety
At shift start, verify flow, tank levels, pumps, blowers, instrumentation and abnormal odors. Apply lockout/tagout, confined-space permits, chemical SDS and gas monitoring where applicable. No live operational changes should be based solely on this guide.
10 — Educational P&ID
Process: influent → screening → equalization → chemical treatment / DAF → biology → clarification → polishing. Typical measurement points include FI/FT (flow), LI/LT (level), pH, DO and sampling ports. Always refer to the plant's actual approved P&ID.
View interactive process diagrams11 — Paper mill operating cases
Starch loss during size-press upset
COD may rise sharply. Investigate the starch kitchen, process drains, equalization buffer and biological oxygen demand.
Wet-end fiber retention loss
Fiber-rich white water can increase TSS and DAF sludge. Compare retention trends with DAF loading and chemical dosing.
Cleaning chemical shock
Changes in pH or toxicity can affect biology. Investigate source segregation, neutralization controls and permitted handling.
12 — Performance trends
Compare daily COD/TSS removal, pH, DO, sludge volume and flow over time. Use the lab dashboard to save local measurements and export CSV for further analysis.
Open lab trends and reportsTechnical reference: plant supplier manuals, approved operating procedures and validated laboratory methods take precedence over educational examples.