The San Rocco wastewater treatment plant, managed by MM Spa, is a crucial hub of Milan’s water infrastructure. Situated within the South Milan Agricultural Park (Parco Agricolo Sud Milano), between the municipalities of Rozzano and Opera, the facility handles a capacity of over one million population equivalent, serving approximately 40% of the Lombard capital’s sewage.
Despite the adoption of deodorisation systems prior to atmospheric release, facilities of this scale often face negative local perception: the fear that the plant may cause unpleasant odours in the surrounding areas is a constant challenge for operators. To monitor the actual impact and obtain objective data, a strategy was implemented based on the installation of three OlfoSense electronic noses and the use of the SmitOlfo software platform.
A three-level monitoring strategy
The positioning of the instruments at the San Rocco plant was custom-designed to cover the various types of emission sources on-site. The system is organised across three key points:
- Channeled Emission: The first OlfoSense was installed directly at the stack, integrated with a sonic weather sensor. This station intercepts channeled emissions before they disperse.
- Diffuse Source (Surface Emissions): A second device was positioned in the tank area, equipped with a sampling system designed to monitor the air immediately above the water surface.
- Validation: The third instrument was placed at the plant entrance. Its function is strategic, acting as a control to validate the data fallout model.
From data to simulation: the SmitOlfo platform
The SmitOlfo platform centralises the data acquired by the three instruments. The system receives data and, by integrating it with real-time meteorological conditions detected by the sonic sensor, develops dynamic simulations of odour dispersion.
On one hand, this allows operators to verify the plant’s actual impact on the surrounding area in real-time, enabling prompt intervention in operational management should any anomalies occur. On the other hand, MM Spa now possesses an irrefutable data history: objective proof that allows them to verify – in the event of external complaints – whether the plant was actually responsible or if the source of the nuisance lay elsewhere.
In a sensitive context such as the South Agricultural Park, the transition from subjective perception to analytical measurement transforms emission management from a potential critical issue into an example of excellence and environmental responsibility.
