Client context
The client is a large municipal operator responsible for water and wastewater management and water protection in the region. Following the ecological disaster on the Oder River in 2022, this topic became a priority for operators across the country. Petroleum hydrocarbons (C10–C40) enter municipal wastewater from numerous dispersed sources: runoff from roads and parking lots, fuel stations and transport bases, automotive workshops and car care services, car washes, improper disposal of oils (so-called garage DIY), illegal discharges, and failures of networks and tanks. In wastewater, they occur as an oil-in-water emulsion.
The key problem is the nature of the contamination: petroleum-derived substances flow on the surface, and discharges tend to be intermittent and short-lived. Continuous monitoring was required, not single grab samples.
Challenge.
- Traditional laboratory sampling detects only large discharges and with a delay of several hours, by which time the contaminated wastewater has already reached the receiving water body.
- Illegal, intermittent discharges evade control based on spot sampling.
- Exceeding the limit carries the risk of administrative penalties and revocation of the integrated permit, as well as damage to the biological stage of the treatment plant.
- There was a lack of a tool for continuous monitoring and immediate decision-making.
Solution
We installed the Spectrally™ X1 analyzer directly in the wastewater flow. It performs continuous compositional measurement for petroleum hydrocarbons and automatically signals their presence (yes/no detection), notifying operators. This is supported by the physics of the method itself: water produces a very weak Raman signal, so it does not drown out contaminants, and the measurement focuses on the target substances.
Installation and commissioning took one day, and the system operates without reagents or consumable parts. It works under the harsh conditions of municipal wastewater: in the presence of suspended solids, with variable medium composition, and without service windows.
Results
| Metric | Result |
|---|---|
| Inline detection | presence signal of hydrocarbons (yes/no detection) |
| Quantitative determination | down to single ppm in a model system |
| Commissioning | installation in 1 day, no reagents or consumable parts |
| Detectability | intermittent, illegal discharges missed by spot sampling |
| Reference method (offline) | GC-FID per EN ISO 9377-2: 60–120 min plus extraction |
Water and wastewater segment. Client anonymized.
What this means for your process
If your facility discharges wastewater covered by an integrated permit, continuous hydrocarbon monitoring provides what a periodically collected sample cannot: an immediate signal of contamination presence before it reaches the receiving water body. This is a direct response to the continuous monitoring requirement of Directive IED 2010/75/EU and a basis for rapid response and identification of the discharge source.
The most reliable way to verify on a specific stream is a short feasibility study on real wastewater samples.
