We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Fate of microplastics during conventional and hydrothermal treatments of sewage sludge: a short review
Summary
This review examines the fate of microplastics during conventional and hydrothermal treatment of sewage sludge, noting that approximately 90% of microplastics entering wastewater treatment plants are retained in sludge. Researchers found that while conventional disposal routes concentrate microplastics in sludge destined for land application, hydrothermal treatments offer potential pathways to degrade or transform microplastics, though the efficiency and byproducts of these processes require further investigation.
Abstract Microplastics (MPs) in wastewater streams have become an issue for wastewater treatment plants (WWTPs). During wastewater treatment, 90 % of MPs entering the WWTPs get trapped within the sludge matrix. Due to high concentration of MPs in sludge, conventional sludge disposal options such as land application, anaerobic digestion and composting can become a secondary source of MPs to the environment. Moreover, traditional sludge technologies stabilise sludge with little to no effect on the MPs concentration. Alternatively, hydrothermal (HT) treatment has been gaining momentum for the disposal of wet wastes, such as food waste and sludge. In addition to waste stabilisation, HT treatment can reduce the negative effect of MPs, reduce overall MPs concentration in the treated stream and produce valuable products. The reduction in MPs concentration from sludge depended on the choice of HT treatment used. An HT process with a higher reaction temperature can substantially reduce MPs concentration, whereas a low-temperature HT process may convert MPs to nano-plastics. Hence, the fate of MPs during various HT processes needs to be studied in detail to select the low-cost and environmentally sustainable solution for sludge disposal.