Tertiary Treatment of Effluent from a Rotating Biological Contactor with Horizontal Subsurface Flow Constructed Wetlands
The total amount of wastewater produced on the different buildings of the campus of the K.H.Kempen is treated in
a rotating biological contactor (RBC). To improve the effluent quality, horizontal subsurface flow constructed
wetlands (HSSF) will be used to decrease the nitrogen and phosphorous content.
The experimental pilot plant consists of  6 mesocosms:  2 mesocosms will treat the effluent from the RBC, 2 will
treat a mixture of 50% effluent and 50% influent and in 2 mesocosms influent of the RBC will be distributed. Two
types of filtration materials will be evaluated: lightweight expanded clay aggregates and gravel. The mesocosms are
planted with Phragmites australis.

Pilot Plant

Horizontal Subsurface Flow, 6 mesocosms
Surface area
2 m
0.6 m (water level)
Length x Width
2 m x 1 m
Hydraulic Loading
0.1 m/m.day
Hydraulic Residence Time
3.91 days
Filtration Materials
3 x lightweight expanded clay 0/4; 3 x gravel 2/12
Phragmites australis
Constructed Wetlands