Improving biorefinery sustainability and profitability by cultivating aquatic plants on ozonized distillery effluents

Abstract

Industrial production of biogas offers a way to manage distillery leachate. The waste is usually subjected to anaerobic digestion for producing biogas. However, the effluent from anaerobic processes has high chemical oxygen demand (COD) and is harmful to the environment. An effective method of lowering COD is ozonation. Effluent from biogas plants after ozonation has the potential for use in breeding grounds for plants of the Lemnaceae family. Thus, they can provide a valuable additional source of biomass for the production of bioethanol. Lemna minor L. and Spirodela polyrhiza cultures were grown in media with the addition of 2.5% PFE, which had been treated by ozonation for between 6 and 50 min. Using ozonated effluent was an effective cultivation technique in all variants. The analyzed parameters were plant growth, chlorophyll index, fresh plant weight and photosynthetic traits (net photosynthesis, stomatal conductance, transpiration and concentration of intercellular CO2). The best growth of Lemna minor L. was observed in the media with PFE treated for 12 min. Similar effects were obtained for S. polyrhiza, with ozone treatment for 12 and 25 min. The results show the potential of using ozone-treated post-fermentation leachate as a supplement in culture media.

Sustainability of Biorefineries: Challenges and Perspectives

“…Energies 2023, 16, 3786 2 of 24 Sustainability has been defined as the perfect balance between economic, environmental, and social dimensions [7]. Furthermore, different perspectives have been added to the sustainability concept involving political, technical, and safe and security aspects [8].…”

“…Even so, biomass upgrading processes and biorefineries are evolving constantly to find new ways to minimize residues, increase products portfolio, and upgrade all biomass fractions [15]. For example, ozonation has been studied as an efficient way to decrease the chemical oxygen demand (COD) of anaerobic digestion effluents [16]. Furthermore, microorganisms have been studied as potential options for improving substrate consumption [17].…”