EVALUATION OF THE REMOVAL OF MATURE LEACHATE ORGANIC CHARGE BY A COUPLED SYSTEM: COAGULATION-FLOCCULATION-ANODIC OXIDATION

Abstract

In this work, we evaluated the removal of organic matter measured as COD contained in mature leachate from the landfill to Tuxtla Gutierrez, Chiapas, Mexico, based geographically in 16 ° 39 'north latitude and 0.819 ° 12'0 .85 93 west longitude, with an average elevation of 960msnm. With the application of a coupled system. As a first step we applied the coagulation-flocculation process to different pH values (7, 6 and 5) using as a coagulating solution FeCl3 2.2 g L-1, fast and slow mixing were performed at 250 rpm for 80 seconds and 30 rpm for 20 minutes, respectively. The best treatment obtained was subjected to the anodic oxidation step using boron-doped diamond (BDD) electrodes at different current intensities (CI) 100, 200 and 300 mA and at pH 3, 5 and 7. The oxidation time was three hours. The higher COD removal (48%) was achieved at pH 5. Anodic oxidation on the best treatment (pH = 3, CI = 300 mA) reached a COD removal of 83%, resulting in a 90% overall removal with the application of the coupled system and increased biodegradability by 69.5% (0.16 to 0.23).

Key Words: Anodic oxidation, Coagulation-Flocculation, mature leachate.