Removal of Phosphorus from Hypolimnetic Lake Water by Reactive Filter Material in a Recirculating System—Laboratory Trial

Abstract

A toolbox of methods must be available for the remediation of lakes and water bodies suffering from eutrophication. One method suggested is hypolimnetic withdrawal based on a closed-circuit system. Prior to the start of a pilot-scale test at Lake Hönsan, Sweden, a laboratory trial with containers filled with water and bottom sediment from this lake was performed. A peristaltic pump distributed equal bottom water volume to four columns, two filled with glass beads and two with the filter material Polonite, and then back to the surface of the containers. The reactive filter medium (RFM) removed phosphate (PO4-P) efficiently (98.6%), despite the relatively low influent concentration (390 µg L−1). The control column filled with glass beads, removed 2.9% of the PO4-P. The anoxic sediment, containing 2.47 mg P g−1, released PO4-P, which was indicated by the increased concentration in near-bottom water. The redirected water after RFM filtration had high pH (x¯=11.1); however, an equalization took place in the water mass to a lower but still increased pH value (x¯=8.7) compared to the control (x¯=7.02). This article reports the pros and cons of a full-scale system using the proposed method.

Tretinio Nuotekų Valymo Filtruojant Per Sluoksniuotą Užpildą Tyrimas

“…Daugelio Europos vandens telkinių būklė yra prasta dėl eutrofikacijos (Renman & Renman, 2022). Europos vandens politikos siekis yra tas, kad vėliausiai iki 2027 m. visose upėse, ežeruose, pakrančių ir tarpiniuose vandenyse būtų pasiekta gera ekologinė būklė (apibrėžiama kaip nedidelis nukrypimas nuo beveik natūralių sąlygų) (Poikane et al, 2019).…”

Removal of Phosphorus with the Use of Marl and Travertine and Their Thermally Modified Forms—Factors Affecting the Sorption Capacity of Materials and the Kinetics of the Sorption Process

“…So far, well-maintained reactive materials (in terms of phosphorus binding) have been described in detail in a review [ 17 ], which presents natural and synthesized materials along with their modifications, waste, and commercialized materials, such as Polonite ® , which has been thoroughly investigated in this area [ 27 , 28 , 29 ]. Additionally, the group of phosphorus sorbets includes iron-calcium salt [ 30 ], Tunisian activated clays [ 31 ], hybrid material of Mg/Al-layered double hydroxide and almond shell biochar [ 32 ], biochars [ 33 , 34 ], magnetic La 2 (CO 3 ) 3 /CoFe 2 O 4 /biochar [ 35 ], and calcium-modified attapulgite [ 36 ].…”

Removal of Nitrogen and Phosphorus from Wastewater Using Layered Filter Media

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