Wastewater treatment and biomass production by slow rate systems using different plant species

Natural treatment systems especially those based on land treatment, remain the only viable choice for wastewater treatment and reuse in small rural communities. In order to develop the appropriate technology required a slow rate (SR) systems were established at Skalani, a small village close to Iracklio, Greece. The SR systems were planted with four plant species eucalyptus, acacia, poplars and reeds to evaluate their effects on wastewater treatment and produced biomass. Systems performance were evaluated by monitoring BOD, COD, TSS, TKN, NH₃-N, NO₃-N, FC, and TC in soil solution and soil samples taken from the 15, 30 and 60 cm of the soil depth. The SR systems, displayed a good performance as regards COD BOD, TKN, NH₃-N and bacteria removal (TC and FC). However, relatively increased values of NO₃ were detected in 60 cm. In terms of plant species used, there were no significant differences in treatment efficiency among the four SR systems. Although, significant differences were observed in biomass production with acacia trees producing the greatest amount of biomass followed by reeds, while the lowest one produced by eucalyptous and poplar trees.