The plant · Reuse skid R1

One skid. Four stages. Most of your water back.

Tarn is a water reuse plant built on a single skid. It sits beside your production line, takes the water the line sends to drain and returns most of it at process grade. Each stage removes something the next one cannot handle.

General arrangement · Top to bottom

Follow the water through the plant.

01 · Screen

Rotary drum screen

The water enters a turning drum of wedge wire. Anything over half a millimetre stays on the wire, a spray bar washes it into a trough, and the screenings drop into a skip.

Aperture
0.5 mm wedge wire
Drum
Ø 1.2 m, 2 to 12 rpm
Removes
Fibres, grit, coarse solids
Leaves as
Screenings to a skip
01 · SCREENROTARY DRUM SCREEN · SECTION A-AFROM THE LINE · RAW EFFLUENTPARTS1 FEED, RAW EFFLUENT2 DRUM, Ø 1.2 M, 2 TO 12 RPM3 WEDGE WIRE, 0.5 MM4 SPRAY BAR, BACKWASH5 SCREENINGS TO SKIP6 TRANSFER PUMP12345602 · SETTLELAMELLA CLARIFIER · SECTION B-B55°PARTS1 FEED, SCREENED2 PLATES AT 55°, 50 MM PITCH3 LAUNDER, V-NOTCH WEIR4 SLUDGE HOPPER5 SLUDGE TO PRESS6 CLARIFIED TO FILTER12345603 · FILTERULTRAFILTRATION · SECTION C-CPT101PT102PARTS1 FEED PUMP2 PT 101 / 102, TMP3 HOLLOW FIBRE, 0.02 µM4 POTTING5 PERMEATE TO POLISH6 CONCENTRATE TO DRAIN12345604 · POLISHREVERSE OSMOSIS AND UV · SECTION D-DUIT201TO THE LINEAIT301PARTS1 HP PUMP2 RO, 3 × 4 IN VESSELS3 UV, 254 NM, 40 MJ/CM²4 UIT 201, UV INTENSITY5 AIT 301, TURBIDITY LOG6 SAMPLE POINT123456TARN · REUSE SKID R1SECTIONS A-A TO D-D · 1:20ISSUED FOR INFORMATION
Sections A-A to D-D, in the order the water flows

Specifications

Sized for a loading bay.

Footprint
12.2 × 2.4m
Operating weight
18t
Daily flow
50 to 400m³ a day
Returned to the line
Up to 80% by volume
Power
1.2kWh per m³
Tie-ins
2one in, one out
Controls
PLCweb dashboard
Data
60s logging, CSV export
Noise
Under 70dB at 1 m

Limits

What Tarn does not take.

  • Water above 40 °CThe membranes need it cooled first. A plate heat exchanger before the skid usually does it, and the heat goes back to the process.
  • Stable oil emulsionsFree oil is fine. Emulsified oil above 200 mg/L needs breaking before it reaches the filter.
  • SolventsSolvent-bearing streams go to their own treatment. We will tell you at the survey if a stream is one of them.
  • Heavy metals above discharge limitsPlating rinse is fine; concentrated baths are not. The survey separates the two.

Monitoring

Every reading, every 60 seconds.

Turbidity, flow and pressure are logged at the outlet and kept on the skid and in your dashboard. You can export them for an auditor or a permit.

Outlet log, AIT 301 · one hour
TimeTurbidity, NTUFlow, m³/hTMP, barUV, mJ/cm²
08:41:000.0911.80.3441.2
08:42:000.0811.90.3441.0
08:43:000.1012.10.3540.9
08:44:000.0912.00.3541.1
08:45:000.0811.90.3641.3

Questions

What plant managers ask first.

Do we need a new building?

No. The skid stands outside or in a bay on a level slab, with a power supply and two pipe connections.

What happens to the sludge and the screenings?

Screenings go to a skip. Sludge is pressed into a cake and leaves as solid waste, which is usually cheaper than sending the water to drain.

Who maintains it?

We do, under a service contract: a visit every quarter, the membranes on a schedule, and an alert to our engineers if a reading drifts.

What if our water changes?

The plant reads its own inlet and outlet. If the inlet changes, the controls adjust the dose and the backwash, and we hear about it before you do.

Can we rent it instead of buying it?

Yes. Most sites start on a rental after the pilot and buy the skid once the figures are proven on their line.