The effects of hydraulic loading,gas/water ratio,and filter bed thickness on the treatment capacities have been studied by the experiments using hybrid biological aerated filter(HBAF) for treating the synthetic detergent wastewater.The results show that the removal rates of COD and LAS are reduced rapidly with the increase of hy-draulic loading,and the best gas/water ratio is 4∶1.There is an index relationship between the COD and LAS con-centrations and thickness of corresponding filter bed.Using HBAF for t...