Déchets du centre d’enfouissement technique de Sfax (Tunisie) : nature, composition et traitement

Landfilling is the strategy adopted in Tunisia to ensure sustainable solid waste management. The Sfax controlled landfill is one of the technical landfills that have been set up. This study presents the main categories and characteristics of household waste buried in the Sfax controlled landfill, as well as the physic-chemical and micro-biological properties of the generated leachates. The leachates treatment processes applied at the station level are presented and their performance is discussed. The results of the waste characterization show the dominance of the potentially biodegradable fermentable fraction (69%). The distribution by particle size of the waste shows a dominance of the average fraction whose particle size is between 20 and 100mm. The characterization of leachates generated shows the presence of a high organic load that is difficult to biodegrade, a high content of ammoniacal nitrogen and recalcitrant compounds such as phenols. We also note the presence of some micro-pollutants minerals and certain pathogens. The toxic nature of leachates has been demonstrated by microtoxicity and phytotoxicity tests. The monitoring of the operation of the leachates treatment plant shows a significant variability of the quantities treated, which explains the filling of the storage ponds.