Tertiary treatment - Fish Come Back to the River Wupper
Providing treatment capacity for approx. 700,000 population equivalents, the Buchenhofen Clarification Plant is the largest wastewater plant of the “Wupperverband” (Wupper River Association).The plant handles up to 370,000 m³ of wastewater per day.
Looking to decrease effluent phosphate content, the plant’s engineering staff decided to add a flocculation-filtration station as the final step in the treatment process in the year 1994. The station consists of 28 open multilayer filter units, each with an upper filter media layer of EVERZIT® N. The total volume of EVERZIT® N used in the 28 units is more than 2300 m³. In this process step, ferric chloride is added to the wastewater as a flocculant to bind the phosphate prior to filtration. The resultant suspension is then passed through the EVERZIT® N multilayer filters, removing phosphate and other pollutants from the wastewater in a highly effective and cost-efficient manner.
While the Buchenhofen Clarification Plant has been in operation for over 100 years, it has reached a new level since adding the EVERZIT® N process step. Downstream water quality in the River Wupper has improved significantly. The improvement is documented by pollutant level testing and also by substantially restored fish populations, a clear sign of enhanced water quality.
Used as the upper layer in these multilayer filter beds, EVERZIT® N increases treatment capacity and reduces operating costs by providing specific benefits:
Aachen-Soers, Aachen-Eilendorf, Bielefeld-Brake, Bocholt, Bonn, Düsseldorf-Süd, Emsdetten, Eriskirch, Hückeswagen, Köln-Weiden, Krefeld, Mannheim-Sandhofen, Neuss-Ost, Paderborn-Sande, Salzgitter, Stuttgart-Sindelfingen, Wuppertal-Kohlfurt
|Capacity of the multi-layer filters:||approx. 20.000 m³/h|
|Number of filters:||28 open multi-layer filters|
|Total surface:||1680 m²|
|Filtration velocity:||approx. 12 m/h|
|Filter material||Height||Grain size|
|EVERZIT® N:||1400 mm||1.4 - 2.5 mm|
|Quartzsand:||400 mm||0.71 - 1.25 mm|
|EVERZIT® BB:||100 mm||2.5 - 5.6 mm|
|EVERZIT® BB:||100 mm||7.1 - 12.5 mm|