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Article Tier 2 Gut & Microbiome Remediation Sign in to save

The Fate of Microplastics During the Anaerobic Digestion of Thermally Pretreated Sludge

Global NEST International Conference on Environmental Science & Technology 2022 1 citation

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This study tracked the fate of microplastics through the anaerobic digestion process used to treat sewage sludge at a wastewater treatment plant, finding that most microplastics survived the digestion intact. Since digested sludge is often applied to agricultural land, this means microplastics can be transferred from wastewater systems into soils where food is grown.

Study Type Environmental

The presence of microplastics (MPs) in the water environment has raised as an issue of great concern, mainly due to their persistence and potential adverse effects on biota. Municipal wastewater treatment plants have been claimed among the most important point source of MPs. Nevertheless, they act as a barrier for the spread of MPs in water, since a significant amount of these pollutants concentrates in the sludge originating from wastewater treatment. This study focuses on the presence of MPs in sewage sludge, with the main aim of assessing their fate during the mesophilic anaerobic digestion of thermally pretreated sludge. MP abundance in the digestate as well as the anaerobic biodegradability of the pretreated substrates were assessed. Experimental results addressed preliminary considerations on the effects of high temperature on the MPs as well as on their influence on anaerobic degradation processes.

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