10.4122/1.1000001616
Buts, L.
L.
Buts
Thoeye, C.
C.
Thoeye
Gueldre, G. De
G. De
Gueldre
Treatment of CSO water using floating plant beds
DTU Library, Technical University of Denmark (DTU)
2005
Conference full text
Balancing pond
combined sewer overflow
ecological engineering
floating plant bed
wastewater treatment
Aquafin, Research
Research
Aquafin
2005
en
10.4122/1.1000001615
application/pdf
A pilot installation treating a combined sewer overflow (CSO) at Bornem, Flanders is built. The construction comprises a presettler and a plug flow treatment zone with floating vegetation elements. The installation is aimed to treat efficiently a so-called two-year overflow event of 2,309 m\302\263 volume and 0.17 m\302\263/s peak flow. During the past three years a number of overflow events were registered. Initially the system performed well, with an observed COD-removal efficiency of 68% and an SS-removal efficiency of 95%. Even nutrient removal took place with values of 37% and 61% for N and P respectively. There was also a becoming \342\200\234natural\342\200\235 (presence of plankton and day/night respiration regimes) of the water. Over the years a decrease in performance was noticeable. During some events more was discharged then brought into the system. This was especially the case for N. It has to be noted though that the most stringent standards for the discharge of treated wastewater in Flanders were almost never exceeded. Overall the current discharge of the overflow treatment is a significant improvement, but maintenance is necessary to keep the system performing well. The applicability of the evaluated system is mainly the treatment of CSO\342\200\231s causing significant ecological damage.