In a wastewater treatment plant, a lift station or a sludge treatment unit, odours are often the first noticeable sign of a deeper problem: sulphur and nitrogen compounds that build up, attack equipment and degrade working conditions. Ventilation plays a dual role here: containing and extracting foul air towards odour treatment, while withstanding that aggressive atmosphere itself. This is exactly where the SEAT 35 comes in.
Odours and corrosion: one and the same problem
Water treatment processes – pre-treatment, basins, sludge thickening and dewatering – continuously release gases and vapours: hydrogen sulphide (H₂S), mercaptans, ammonia, methane. Sulphur compounds are responsible for the characteristic "rotten egg" smell noticed by neighbours and operators alike.
These same gases are corrosive. In the presence of moisture, H₂S promotes the formation of acidic compounds that attack metals: steel impellers, housings and ductwork deteriorate, airflow performance drops and extraction becomes less effective… which in turn makes odour nuisance worse.
What a water treatment fan must deliver
- 🧪Chemical resistance to sulphur and ammonia compounds and saturated humidity.
- 🔄Continuous operation: air extraction in treatment plants must run 24/7.
- 📈Pressure reserve to move foul air through ductwork and the odour control unit (gas scrubber, filter).
- ⚠️An ATEX option for hazardous areas: presence of methane, chlorine drum storage.
- ☀️Outdoor durability, as fans are frequently installed on rooftops or next to the structures they serve.
The SEAT 35, designed for corrosive atmospheres
The SEAT 35 is a corrosion-resistant polypropylene centrifugal fan with direct drive (impeller mounted on the motor shaft). Its polypropylene housing is suited to the extraction of corrosive gases: where a metal fan deteriorates in contact with H₂S, polypropylene keeps its integrity.
Key specifications
| Parameter | SEAT 35 |
|---|---|
| Airflow | 1,500 to 9,000 m³/h |
| Total pressure | 200 to 1,500 Pa |
| Inlet / outlet diameter | 315 mm |
| Material | Corrosion-resistant polypropylene, UV-stabilised (HALS) |
| Drive | Direct |
| Motors | IP55 asynchronous from 1.5 to 7.5 kW · IP66 EC version available |
| Maximum temperature | 60 °C |
| ATEX | Zone 2 version available |
| Testing | AMCA 210-85 / ISO 5801 |
For reference, the datasheet gives two operating points: 3,770 m³/h at 290 Pa at 930 rpm (LpA 59 dB(A) at 3 m) and 5,880 m³/h at 704 Pa at 1,450 rpm.
Why it solves odour issues
- It lasts in contact with sulphur gases: no corrosion of the housing or impeller, so no gradual drift in extracted airflow.
- Its pressure range leaves headroom when captured air must pass through ductwork and an odour control unit before discharge.
- Speed control (frequency inverter or EC motor) adjusts airflow to the actual needs of the structure, without oversizing.
- The ATEX Zone 2 version covers rooms with an identified explosion risk. With an inverter, a PTC sensor is mandatory on an ATEX motor.
- UV-stabilised polypropylene allows outdoor installation on a metal stand, high-protection base or roof kit.
Typical configurations
Datasheet and CAD files: freely available
We work closely with design offices, integrators, and companies building water treatment plants worldwide. What they ask us for first is usable data: performance curves, dimensions, CAD models ready to drop into their drawings.
Here is what we make available to them, and what they value most: the complete SEAT 35 documentation, accessible directly with no form to fill in:
- 📄SEAT 35 datasheet (PDF): dimensions, airflow/pressure curves, acoustic data, standard, ATEX and EC motor references.
- 📐2D / 3D CAD and BIM files: ready to drop into your drawings and digital models. 3D viewer available on the product page.
- 📚Catalogues and documentation: manuals, accessories, mounting options.
In water treatment, odours and corrosion go hand in hand. Made of corrosion-resistant polypropylene, the SEAT 35 provides continuous, long-lasting extraction of air laden with H₂S and ammonia, with a range of 1,500 to 9,000 m³/h, up to 1,500 Pa, an ATEX Zone 2 version and outdoor installation capability. Datasheet and CAD files are freely downloadable.
Working on a treatment plant, lift station or odour control project?
Our engineers support you from sizing to commissioning.
👉 Contact a SEAT engineer · See the water treatment range · Download the catalogue
📍 Meet us at STEP by Pollutec, 1–2 December 2026, Paris Expo Porte de Versailles – Hall 1, stand G047.
