THE ROLE OF DUCKWEED (LEMNA MINOR L.) IN SECONDARY CLARIFIER TANKS

Year 2008, Volume: 12 Issue: 1, 28 - 31, 01.06.2008

Engin Gürtekin Nusret Şekerdağ

Abstract

In this study, the effects of duckweed (Lemna minor L.) presence on the effluent water quality and settling characteristics in the secondary clarifier tank of a conventional biological treatment plant were investigated. For this purpose, the performances of the secondary clarifier with and without duckweed were compared. In the secondary clarifier tank with duckweed, COD, BOD5, ammonium and phosphate removal efficiencies were higher by 15, 25, 35 and 45%, respectively. SS concentration of effluent and values of sludge volume index (SVI) were the same. The results showed that duckweed contributes to treatment efficiency of conventional biological treatment plant, which reduces the need of tertiary nutrients removal.

Keywords

Duckweed, wastewater, treatment, secondary clarifier.

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