A biofilm system device with natural zeolite and peat was designed to observe the nitrogen and phosphorus removal efficiency in micro-polluted water.The mechanism and effect of pollutants removal were also investigated after the formation of biological membrane system.The results showed that the ability of phosphate removal in aqueous solution by peat was improved,but peat released ammonium nitrogen,the ability of ammonium nitrogen removal in aqueous solution by natural zeolite was decreased.Ammonium nitrog...