Comportamento temporal dos parâmetros físico-químicos do lixiviado gerado pelo aterro sanitário em Campina Grande-PB

Abstract

Urban Solid Waste (MSW) when deposited in sanitary landfills undergo biodegradation processes, causing the formation of by-products that, if improperly disposed of in the environment, compromise the population's natural resources and health, for example the leachate, which is a liquid by-product , characterized by its dark color, unpleasant odor, presence of contaminants, in addition to high concentrations of recalcitrant organic matter, ammonia and heavy metals. Therefore, in view of this complexity and heterogeneity, it is important and necessary to study the physical-chemical parameters that characterize this liquid, in order to know the degradation processes that occur inside the waste cells, and the external influences that affect this by-product, thus providing prior knowledge about the constituents of the leachate, in addition to auxiliary studies seeking forms of treatments for this by-product. In this context, this research aimed to analyze the behavior of the physical-chemical parameters: pH, Volatile Fatty Acids (VFA), Total Alkalinity (TA), Total Ammoniacal Nitrogen (TAN), Chemical Oxygen Demand (COD) and chlorides in the leachate of the Landfill of Campina Grande-PB (ASCG) from July 2017 to December 2019, observing variations in the concentrations of these parameters, their correlations and external influences. In addition, the relationship between the flow of rain and the leachate generated was verified and statistically analyzed the rainy and non-rainy periods. The methodology of this research was carried out jointly with the Environmental Geotechnics Group (GGA) that performs the environmental monitoring of the referred landfill, at the Environmental Geotechnics Laboratory (LGA), belonging to the Federal University of Campina Grande (UFCG), Campus I. In view of the results obtained, it was verified that the leachate flow was influenced by the precipitation. There was a great variability in physical-chemical parameters, as well as it was possible to indicate that the leachate is in the methanogenic phase of degradation. The linear correlations between the parameters ranged from weak, moderate and strong, and through descriptive statistics it can be noted that the precipition influenced the physical-chemical parameters in a punctual and not general way. In addition to environmental factors such the precipition, it is worth mentioning that interference also occurred due to recirculation carried out in periods without rainfall, and the grounding of new waste. The leachate analyzed has similar characteristics to the others studied in the literature, and is important for exploring efficient treatment techniques, since they are not available for direct release into water bodies.