Assessing Odour Emissions and Environmental Impact of a Recycled Paper Production Facility

Odour emissions from recycled paper mills are an operational, regulatory, and community concern, yet facility-scale data remain limited. We characterised odour levels across key process locations at an industrial recycled paper production plant using dynamic olfactometry in accordance with EN 13725. Air samples were collected at the beginning, middle, and end of the paper machine, and at three wastewater treatment plant points: final effluent outlet, pumping station, and open sedimentation tanks. Geometric mean odour concentrations along the paper machine were 181 ouE/m³ at the beginning, 362 ouE/m³ in the middle, and 310 ouE/m³ at the end. In the wastewater treatment plant, odour levels were lowest at the outlet (36 ouE/m³), higher at the pumping station (72 ouE/m³), and highest near open sedimentation tanks with peak at 181 ouE/m³. The spatial gradients and episodic peaks highlight priority targets for emission control, particularly mid-machine zones and uncovered wastewater surfaces, and illustrate the value of site-resolved odour mapping for process optimisation and mitigation planning. These data contribute to the limited published evidence base on odorous emissions from recycled paper operations and provide benchmarks for future monitoring, technology evaluation, and regulatory dialogue.