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Open-Frame Modular Wastewater Pilot Plants

Lightweight aluminium-extrusion or steel space-frame holding swappable treatment modules. The shape that makes the process visible — ideal for teaching, training, parallel-process comparison and the trials where the design team wants to watch every reaction happen. Highest reconfigurability of any pilot form factor.

What an Open-Frame Pilot Is

A Plant You Can See

An open-frame modular pilot is built around a lightweight aluminium-extrusion (typically 40×40 mm or 45×45 mm slot-and-tab profile) or steel-tube space-frame. Treatment modules — reactors, dosing rigs, sensor packs — are slotted into the frame at standard interface positions and connected with quick-release process and electrical links. The frame itself is the chassis; the science is the modules.

This is the form factor of choice when reconfigurability is more important than weather protection, and when the design team or trial visitors need to see what is actually happening to the water rather than reading it off a SCADA screen.

Advantages

Why Open-Frame

1. Highest Reconfigurability

Swap an MBBR reactor for an SBR over lunch. Add a third coagulant-dosing rig in parallel. Move the polishing filter ahead of the biological reactor and back again to find the right sequence. The pilot is a building set rather than a fixed plant.

2. Process Visibility

Every pump, valve, transmitter, hose and reactor is visible. Excellent for teaching graduate students how a treatment train works; essential for trial visits where the client wants to see the data being made.

3. Lightest per Equipment Volume

No surplus container shell, no heavy steel skid frame. A 20′-equivalent open-frame pilot typically weighs 60–70 % of the same equipment in a containerised build.

4. Trivial Field Modification

If the trial reveals an unexpected fault mode, an extra sensor or a different mixing element can be slotted into the frame the same afternoon — standard tools, no drilling or welding required.

5. Ideal for Academic Programmes

The visible-process design supports postgraduate research where the pilot is itself an experimental platform, not just a black box producing performance data.

6. Re-Use as a Teaching Rig

After the field campaign, the same frame becomes a permanent teaching rig at the home institution. Modules are re-arranged to suit each successive teaching exercise.

Frame Specifications

Three Standard Profiles

Frame typeProfileFrame massBest for
Aluminium extrusion (light)40 × 40 mm slot-and-tab1.8 kg/mIndoor, light-load, frequently-reconfigured pilots and university teaching rigs
Aluminium extrusion (heavy)45 × 90 mm slot-and-tab4.0 kg/mOutdoor or load-bearing pilots; rooftops and industrial test halls
Steel space-frame40 × 40 mm SHS4.7 kg/mHeavier process loads (large reactors, tall column stacks), outdoor exposed pilots

All frame interfaces are standardised so any module built to the standard will fit. We maintain a kit-of-parts catalogue that grows as we build new modules.

Module Catalogue

Building Blocks

Inlet pump module

Variable-speed peristaltic or centrifugal, 0.05–5 m³/h with inline flow meter and turbidity probe.

Dosing module

4-channel peristaltic dosing rack with reagent racks. Mid-trial chemistry change in 15 minutes.

Rapid-mix / flocculation

Variable-speed paddle mixer with G-control. Tapered-G flocculation rig with 3 chambers in cascade.

Clarifier / DAF

Inclined-plate clarifier or skid-mounted DAF cell. Single-glance view of the floc forming and the float clearing.

Biological reactor

MBBR or SBR with transparent acrylic body. Carriers visibly circulate; the operator can confirm mixing by eye.

Filtration column

Glass or transparent acrylic columns showing media bed expansion during backwash. Online ΔP logging.

Disinfection / oxidation

UV reactor with online UVT sensor; ozone contactor; chlorine dosing module.

Control & SCADA

Compact PLC cabinet mounting on the frame; tablet HMI on a swing arm; satellite modem for remote access.

Sampling rack

Refrigerated autosampler with 24 bottles; manifold sampling ports at every stage of the train.

Challenges & Engineering Responses

Honest View

1. Weather Exposure

An open frame on an outdoor site fails fast in heavy rain or wind-blown dust.

Engineering response

Detachable polythene shrink-wrap during transport; canvas awning bolted to the frame for short-term outdoor use; pop-up event tent for longer outdoor deployment. For permanent outdoor service the containerised form factor is the correct choice.

2. Security

Equipment is visible and reachable. Theft and tamper risk on unsecured sites.

Engineering response

Lockable canvas covers, tamper-evident wraps on chemical stores, perimeter intrusion sensors with SMS alert. For high-risk sites, containerised is the safer call.

3. Transport Robustness

Light frames break and fastenings loosen if dropped or jolted in transit.

Engineering response

Disassemble for transport into structural sub-frames + module crates. Vibration-tested module mountings. Re-assembly on site takes a half-day rather than a full day.

4. Hazardous-Area Service

Open frame cannot host nitrogen inerting and cannot contain a vapour release.

Engineering response

For flammable-feed pilots, use the containerised ATEX build. Open-frame is suitable only for non-flammable wastewater trials.

5. Floor Spill Containment

No enclosed floor means a spill goes straight to the site surface.

Engineering response

Detachable spill tray under the frame, sized to contain the largest single-vessel inventory. Visual leak indicators on every connection.

6. Climate Sensitivity

Below 0 °C, instruments freeze; above 35 °C, electronics drift.

Engineering response

Heat-tracing on wet lines, insulating jackets on the most sensitive instruments, shade canopy in hot climates. For climate envelopes outside −5 to +35 °C, switch to a climate-controlled container.

Related Topics

Need a Pilot You Can See?

Tell us the modules and the configuration freedom you need — we will estimate an open-frame build within two weeks.

Industries We Serve

Our expertise spans multiple industries with sector-specific water treatment solutions.