Fate of micropollutants in chemically enhanced primary treatment using recovered coagulants

Tulip Chakraborty; Dharavi Balusani; Lyne Sabourin; Justin Renaud; Mark Sumarah; George Nakhla; Madhumita B Ray

doi:10.1016/j.jenvman.2020.110815

Fate of micropollutants in chemically enhanced primary treatment using recovered coagulants

J Environ Manage. 2020 Sep 1:269:110815. doi: 10.1016/j.jenvman.2020.110815. Epub 2020 May 29.

Authors

Tulip Chakraborty¹, Dharavi Balusani², Lyne Sabourin³, Justin Renaud³, Mark Sumarah³, George Nakhla⁴, Madhumita B Ray⁵

Affiliations

¹ Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario, Canada. Electronic address: tchakra@uwo.ca.
² Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario, Canada.
³ London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario, N5V 4T3, Canada.
⁴ Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario, Canada. Electronic address: gnakhla@uwo.ca.
⁵ Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario, Canada. Electronic address: mbhowmic@uwo.ca.

PMID: 32561017
DOI: 10.1016/j.jenvman.2020.110815

Abstract

In this study, the fate of several micropollutants (MPs) in wastewater due to coagulation using both fresh and recovered aluminum and iron coagulants was determined. 18 MPs from different groups such as antibiotics, food additives, and surfactants were selected and spiked into the primary influent collected from a local wastewater plant. The distribution of MPs in the recovered coagulant and treated effluent after coagulation was determined for both fresh and recycled coagulants. The distribution of MPs in wastewater and the removal during coagulation were compound specific; MPs with log K_ow < 2.5 were predominantly present in the effluent after coagulation, while MPs with log K_ow > 2.5 were sorbed on the coagulated sludge. The distribution ratio (K_d) of all the MPs (diclofenac, clarithromycin, etc.) with log K_ow > 2.5 was determined along with their extent of accumulation in sludge due to the recycling of coagulants. Compounds such as sulfamethoxazole, erythromycin and sulfathiazole, showed low removal during coagulation. The tetracycline group of compounds showed possible chelation with iron and aluminum. Only <10% of the initially spiked MPs with log K_ow > 2.5 was being recycled with the recovered coagulant, thus alleviating the concern of accumulation of the MPs during recycle of the coagulants.

Keywords: Chemically enhanced primary treatment; Coagulant recovery; Micropollutants; Phosphorous removal; Primary sludge.

MeSH terms

Recycling
Sewage
Waste Disposal, Fluid
Wastewater
Water Pollutants, Chemical*
Water Purification*

Substances

Sewage
Waste Water
Water Pollutants, Chemical