Abstract

Traditional waste management in landfills made the leachate a serious environmental problem. Effective treatment for landfill leachate because of high concentration of organic and nitrogen components is of great importance to reduce its adverse impacts on environment. Applicability of leachate pretreatment based on recycling the leachate of fresh waste on old waste was investigated in this study. In first step an LSR with 200L volume filled with fresh waste and had run until its parameters showed degradation for more than 90%. In second step two different landfill simulation reactor (LSR) systems were setup, each set-up consist of two LSRs in series. In the first set-up, both reactors filled with fresh waste and their leachate was recirculated daily by peristaltic pump at constant rate. In the second set-up daily the leachate from fresh waste LSR (A2) was passed through the second LSR (B2) which filled with old waste that prepared in previous step, while at the same time the leachate from reactor B2 was passed through reactor A2. Leachate quality in both set-ups determined weekly for COD, BOD5, ammonia nitrogen (NH3-N) and ammonium nitrogen (NH4-N). Multiple linear regression model was used to describe relationship between experiments data, furthermore equations of the fitted models and degree of accuracy by mean absolute error (MAE) were determined. The results indicate that this procedure has shown significant effect on reduction pollutant components of leachate, also it can be more effective for organic component removal compare to nitrogen removal.