At the Eco-zoning Villerot-Tertre industrial site, Trevi realised a large-scale wastewater treatment plant that collects and purifies nitrogen-rich effluents from multiple companies before safe discharge into the La Haine river.
Challenge
Yara Tertre, specialised in the production of fertilisers and nitrogen-based chemicals, faced the challenge of treating highly nitrogen-loaded wastewater from its industrial processes, combined with domestic wastewater, cooling tower blowdown, and rainwater.
As part of a centralised treatment strategy, the plant also needed to accommodate effluents from other industrial stakeholders in the Eco-zoning area. The complexity of variable flows, concentrations, and operational needs required a high-performance and flexible solution.
Solution
Trevi constructed a new biological treatment plant with integrated flow equalisation through three buffer tanks. The biological system was designed in two parallel lines for optimal ammonium and nitrate removal. To support denitrification, the system allows the use of multiple carbon sources, selected dynamically based on availability and cost.
The excess sludge is stabilised through mineralisation and further dewatered by centrifuge. Air extracted from the sludge handling building is treated in a two-stage odour control system using lava and biofilters. Rainwater collected across the site is also directed to the plant, enabling full-site water management.
Result
Yara Tertre now operates a future-proof wastewater treatment plant that ensures nitrogen discharge remains within legal and environmental standards. Through centralisation and smart buffering, the plant guarantees consistent treatment performance despite varied inflows. The project reinforces both Yara’s environmental leadership and the sustainable ambitions of the broader Eco-zoning industrial site.
