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Improving phosphorus removal of conventional septic tanks by a recirculating steel slag filter

Dominique Claveau-Mallet, Félix Lida and Yves Comeau

Article (2015)

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Cite this document: Claveau-Mallet, D., Lida, F. & Comeau, Y. (2015). Improving phosphorus removal of conventional septic tanks by a recirculating steel slag filter. Water Quality Research Journal, 50(3), p. 211-218. doi:10.2166/wqrjc.2015.045
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The objective of this project was to increase the phosphorus (P) retention capacity of a conventional septic tank by adding a recirculating slag filter. Two recirculation modes and recirculation ratios from 5 to 50% were tested in the laboratory with reconstituted domestic wastewater. The best system was recirculation from the end to the inlet of the second compartment of a septic tank with a 50% recirculation ratio in the slag filter, achieving 4.2 and 1.9 mg P/L at the effluent for total phosphorus (TP) and orthophosphate (o-PO4), respectively, and a pH of 8.8. The calculated size of the slag filter for a two-bedroom house application was 1,875 kg for an expected lifetime of 2 years. The 1 mg P/L level goal was not reached, but P precipitation may be favoured by the relatively high effluent pH reaching the infiltration bed.

Uncontrolled Keywords

on-site wastewater treatment, phosphorus removal, septic tank, steel slag

Open Access document in PolyPublie
Subjects: 1000 Génie civil > 1000 Génie civil
1000 Génie civil > 1006 Génie hydrologique
1000 Génie civil > 1007 Ressources et approvisionnement en eau
Department: Département des génies civil, géologique et des mines
Research Center: Non applicable
Date Deposited: 16 Aug 2021 13:04
Last Modified: 22 Oct 2021 16:46
PolyPublie URL: https://publications.polymtl.ca/9084/
Document issued by the official publisher
Journal Title: Water Quality Research Journal (vol. 50, no. 3)
Publisher: IWA Publishing
Official URL: https://doi.org/10.2166/wqrjc.2015.045


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