Non-Thermal Atmospheric Plasma: a Cutting-Edge Technology For the Valorisation of Food Industry By-Products

Reducing food waste is a critical global challenge with societal, economic, nutritional, and environmental implications. Approximately one-third of all food, including half of all fruits and vegetables, is lost or wasted globally. Food industry by-products, rich in nutrients, offer significant potential for valorisation, supporting the circular economy by reintegrating these materials into the supply chain to create new products. Traditionally, nitrogen fixation for agriculture has relied on energy-intensive methods like the Haber-Bosch and Ostwald processes, which produce significant CO 2 emissions. The Birkeland-Eyde process, using arc plasma, was an alternative but not highly energy-efficient. Recent advancements in non-thermal atmospheric plasma technology (NTAP) show promise for efficient and localized nitrogen fixation, especially beneficial for agriculture. This research aims to evaluate the feasibility of using NTAP to convert vegetable food processing waste, particularly from tubers like beets and potatoes, into high-value biofertilizers. This research aimed to identify and characterize various wastes and by-products from the processing of red beets and potatoes for their transformation and valorization into biofertilizers through sustainable processes. We conducted physicochemical and nutritional analyses of diverse by-products from both red beet and potato processing industries. After this initial characterization, we assessed NTAP technologies as an innovative method for nitrogen fixation, aiming to produce biofertilizers with higher ammonia and nitrate content. This approach was tested using different NTAP configurations, including bubble, frit, and catalyst reactors, operating under various settings, and using air as the working gas. Once the optimal NTAP treatment was determined, we evaluated the impact of the resulting biofertilizers on seed germination capacity. An initial investigation into liquid waste streams from potato processing industries revealed that plasma treatment with a catalyst ...