Mechanical biological treatment (MBT) plants are key in managing urban solid waste by separating recyclable materials that were not sorted at the source and stabilising the organic fraction. However, these facilities face a significant environmental challenge: the emission of volatile organic compounds (VOCs) and the possible generation of odours. This issue can affect both indoor air quality within the facilities and nearby communities, making it essential to implement effective mitigation strategies to treat the generated air.
What are VOCs and why are they generated in MBT plants?
VOCs are chemical substances that easily evaporate at room temperature and can include various hydrocarbons, aldehydes, and alcohols. In MBT plants, VOCs mainly originate from the decomposition of organic matter under aerobic and anaerobic conditions. Some of the compounds that produce the strongest odours include alcohols (ethanol) and terpenoids (e-limonene).
Solutions to mitigate VOCs and odours
To minimise the impact of VOCs in MBT plants, various technological strategies aim to reduce emissions and improve air quality. Some of the most effective solutions include:
Biofilters: they use microorganisms to degrade gaseous pollutants present in MBT plant emissions. These systems channel the air through a biological bed composed of materials such as peat, compost, or wood fibres, where bacteria and fungi metabolise VOCs and convert them into harmless substances. Biofilters are an ecological and efficient solution, offering low operational costs and a reduced environmental impact.
Thermal oxidation: this involves decomposing VOCs using high temperatures (between 700 and 1,000 °C). Through thermal oxidation, organic compounds are transformed into CO₂ and water vapour, eliminating their environmental impact. Although highly effective, this technology’s energy consumption and associated costs can pose a challenge for some facilities.
LIFE ABATE: an innovative solution
Given the growing need for more sustainable and efficient solutions, the LIFE ABATE project emerges as an innovative alternative for reducing VOC emissions in MBT plants. LIFE ABATE aims to implement an advanced mitigation system based on VOC concentration and capture technologies using zeolites and optimised biofiltration.
Through a comprehensive approach, LIFE ABATE seeks not only to improve air quality in treatment plants but also to reduce their environmental footprint and enhance public acceptance of these facilities. Implementing such solutions is key to ensuring the sustainability of the waste management sector and the wellbeing of nearby communities.
Moving towards sustainable management
VOCs and odours in MBT plants pose an environmental and social challenge that requires effective mitigation strategies. Technologies such as biofilters and thermal oxidation have proven to be viable solutions, but continuous innovation is essential to optimise processes. In this regard, the LIFE ABATE project represents a step forward in the search for sustainable and efficient solutions to improve air quality and reduce the impact of MBT plants on their surroundings.