We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastics in real wastewater treatment schemes: Comparative assessment and relevant inhibition effects on anaerobic processes
AI summary Read the abstract
Researchers studied the occurrence and removal of microplastics through different stages of a wastewater treatment plant in Central Italy. They found that while treatment processes removed a substantial portion of incoming microplastics, significant numbers still passed into the effluent, and microplastics also inhibited anaerobic digestion processes used for sludge treatment. The study highlights that wastewater treatment plants are both important barriers against and inadvertent sources of microplastic pollution in receiving waters.
The occurrence, fate and removal of microplastics (MPs) in a wastewater treatment plant (WWTP) in Central Italy were investigated together with their potential adverse effects on anaerobic processes. In the influent of the WWTP, 3.6 MPs.L-1 were detected that mostly comprised polyester fibers and particles in the shape of films, ranging 0.1-0.5 mm and made of polyethylene and polypropylene (PP). The full-scale conventional activated sludge scheme removed 86% of MPs, with the main reduction in the primary and secondary settling. MPs particles bigger than 1 mm were not detected in the final effluent and some loss of polymers types were observed. In comparison, the pilot-scale upflow granular anaerobic sludge blanket (UASB) + anaerobic membrane bioreactor (AnMBR) configuration achieved 94% MPs removal with the abatement of 87% of fibers and 100% of particles. The results highlighted an accumulation phenomenon of MPs in the sludge and suggested the need to further investigate the effects of MPs on anaerobic processes. Accordingly, PP-MPs at concentrations from 5 PP-MPs.gTS-1 to 50 PP-MPs.gTS-1 were spiked in the pilot-scale UASB reactor that was fed with real municipal wastewater, where up to 58% decrease in methanogenic activity was observed at the exposure of 50 PP-MPs.gTS-1. To the best of our knowledge, the presented results are the first to report of PP-MPs inhibition on anaerobic processes.
More Papers Like This
Microplastics in real wastewater treatment schemes: comparative assessment and relevant inhibition effects on anaerobic processes
AI summary Read the abstract
Researchers investigated microplastic occurrence and removal in an Italian wastewater treatment plant, finding 3.6 MPs/L in influent dominated by polyester fibers, with conventional activated sludge achieving 86% removal, and demonstrating that concentrated sludge-associated microplastics can inhibit downstream anaerobic digestion.
The fate of microplastics in an Italian Wastewater Treatment Plant
AI summary Read the abstract
Microplastics were tracked through influent, settler, and effluent stages of a major northern Italian WWTP (serving 1.2 million population equivalents), finding high removal efficiency but continued discharge of fibers and fragments to receiving water and concentration of retained plastics in sludge. The study provides detailed mass flow data for an Italian WWTP and highlights sludge as the dominant plastic-retention compartment.
Microplastics in wastewater treatment plants: Sources, properties, removal efficiency, removal mechanisms, and interactions with pollutants
AI summary Read the abstract
This review examines microplastic sources, properties, removal efficiency, and removal mechanisms across different wastewater treatment plant stages. Researchers found that while treatment plants remove a significant portion of microplastics, they cannot eliminate them entirely, resulting in the continued release of millions of particles into the environment daily through effluent and sludge.
Influence of wastewater treatment process on pollution characteristics and fate of microplastics
AI summary Read the abstract
Researchers investigated microplastic abundance and removal efficiency across four wastewater treatment plants using different treatment technologies, finding influent concentrations between 539 and 1,290 particles per liter that were reduced substantially by primary and secondary treatment. Smaller microplastic particles proved hardest to remove and most likely to persist in final effluent.
Distribution and removal mechanism of microplastics in urban wastewater plants systems via different processes
AI summary Read the abstract
Researchers compared the microplastic removal efficiency of three wastewater treatment technologies and found that the anaerobic-anoxic-oxic process achieved the highest removal rate at 83.9%. Most microplastics were transferred to sludge during primary and secondary treatment stages, with dehydrated sludge containing significant concentrations. The study highlights that while wastewater treatment plants effectively intercept most microplastics, they also redistribute contamination to sludge, which may become a secondary pollution source.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.