Less odour, more clarity
How Empro tackles odour emissions and protects local air quality
Sustainability is about more than circular materials and renewable energy. It also means taking real responsibility for your impact on the surrounding environment. At Empro, we know odour is a sensitive and tangible issue – for neighbours, employees, and local authorities alike. That’s why we invest heavily in advanced odour control, continuous monitoring, and open communication. In this third part of our sustainability series, we explain how Empro doesn’t just manage odour, but tackles it at the source.
Odour is complex – and calls for a smart, layered approach
Processing poultry by-products inevitably produces odorous compounds – especially during hydrolysis and drying. As we break down feather proteins through enzymatic and thermal hydrolysis, sulphur-based compounds are released, including hydrogen sulphide (H₂S) and other organic sulphur molecules. These substances are extremely pungent due to their very low odour threshold – think of the sharp smell of burning hair. Even in trace amounts, they’re noticeable.
Independent air quality assessments by VITO, a recognised and independent research institute, confirm that emissions from Empro consistently stay well below the legal safety thresholds. The VITO report reaffirmed that Empro’s emissions are non-toxic and pose no harm to public health. But for Empro, odour isn’t just about safety – it’s about liveability. And that’s something we take very seriously.
A structured response: from source to surroundings
Prevention: stopping odour before it starts
Our first line of defence is prevention. Empro has made targeted investments in enclosed unloading areas, double-door airlocks, and automated air extraction systems at key emission points. By capturing odours before they escape, we minimise the need for treatment further down the line.
Technology: multiple systems, one shared goal
At Empro, we use a combination of treatment systems – each designed to tackle a specific part of the emission stream. Together, they eliminate more than 99.9% of the original odour load. These results are made possible by continuous innovation and technical upgrades that place us among the leaders in our sector.
A quick overview of the technologies we use:
- Thermal treatment in high-efficiency steam boiler
Odorous gases are incinerated at high temperatures in a state-of-the-art steam boiler – a technology that has been developed and further finetuned in-house at Empro. This process eliminates residual smells while recovering heat for reuse.
- Air extraction and scrubbing
We treat up to 50,000 m³ of air per hour per production line through a system of scrubbers and humidifiers. An oxidative scrubber neutralises odour molecules via a controlled chemical reaction.
- Free flow condensors
To recover the energy and reduce the volume of air that needs to be treated.
- Activated carbon filtration
Specific odour molecules are absorbed by high-grade activated carbon. These filters are replaced frequently to maintain peak performance.
- Biofilter using natural wood substrate
Remaining emissions like ammonia are biologically broken down by nitrifying bacteria in a moist root-wood medium.
- On-site wastewater treatment
All process water is treated biologically in our own facility. This not only removes organic content, but also reduces residual odour in the water. The purified water is reused wherever possible within the plant.
- 38-metre stack (installed in 2023)
As a final step, treated air is released via a tall emission stack, allowing further dilution in the upper atmosphere. This drastically reduces the impact on local air quality.
These technologies are largely connected in series. This layered approach not only increases overall effectiveness, but also provides redundancy – each system reinforces or backs up the previous one.
All of these systems meet the Best Available Techniques (BAT) standards, as defined under Belgian VLAREM environmental legislation.
Monitoring and follow-up: measure, adapt, improve
Odour control isn’t just about technology – it’s also about discipline. Every day, trained staff members known as “noses” perform fixed-point odour checks in and around the facility. In parallel, key air parameters such as H₂S, pH, temperature, and conductivity are continuously monitored.
Every two weeks, independent odour experts from Olfascan carry out unannounced visits to the site to conduct additional assessments. This combination of internal vigilance and external validation ensures that we can act quickly and effectively when needed.
Real progress – and ongoing commitment
Thanks to this integrated strategy, odour impact around Empro has significantly declined in recent years. Independent odour dispersion measurements show that concentrations in nearby residential areas remain well below legal thresholds (98th percentile < 1 ou/m³).
But we don’t stop there. Our infrastructure continues to evolve. We are currently building a new wastewater treatment facility and relocating the unloading zone to enable even better containment. At the same time, we continue working with external specialists and engaging with our local stakeholders.
Because odour control isn’t just a regulatory requirement – it’s part of how we show respect for our surroundings. As CEO Vaast Vanoverschelde puts it:
“Odour is a shared concern. We extract the very best from our proteins – but that same drive for innovation must also apply to the challenges that come with it. Just as we refine our products every day, we need to keep refining our impact. Odour reduction is part of our commitment – day in, day out.”