Enhanced removal of herbicides by different in-site barrier-systems (GAC, FAC, anthracite, lignite coke) in slow sand filtration

Improvement of artificial groundwater recharge via slow sand filtration combined with different in-site barrier-layers (activated carbons, anthracite, lignite coke) was tested. The micropollutant control of the systems achieve significant different pesticides reductions. Operation time depends on the micropore structure and site properties of the activated carbons (Sorption reactor) and reaches a calculated slow sand filter operation time of nearly 6 years (GAC). No distinct improvement of pesticide removal was observed by anthracite (biological reactor). Lignite coke was not used in pilot plant, because of its high pH-value during first 100 bed volumes.