Análise multivariada no comportamento dos recalques em célula experimental de resíduos sólidos urbanos.

Abstract

The settlements in solid municipal waste landfills are defined as vertical downward displacements of the waste. Thus, Problems involving operations, stability and deformability are frequent in landfills. They are often caused by high levels of organic matter present in the waste mass. These factors can be more accuratly analyzed if studied in an MSW experimental cell because it can simulate landfill behavior in a known and/or controlled conditions. . It is important to emphasize that the situation of these settlements in landfills is complex due to the large number of variables that are linked - directly or indirectly - to this mechanism. The aim of this study was to investigate the behavior of settlements associated with geotechnical, physical, chemical and microbiological aspects in an experimental cell of municipal solid waste using a Multivariate Analysis tool. The methodology consisted in the construction, instrumentation and filling of a 9 m3 experimental Cell with USW and the analysis of settlements for statistical aspects and their correlations with physic-chemical and microbiological parameters. The multivariate statistical analysis on principal components was performed initially by generating a correlation matrix with all the variables involved in the process and those were divided into layers to check the level of relationship between them. The MSWs gravimetric and volumetric composition were also done in order to help with the quantification of degrated organic matter throughout the present research. According to the analyzed results, it was observed that the upper layer of waste obtained a better performance in terms of microbial activity, settlements and degradation of organic matter. The anlysis indicated the amount of organic matter decreased drastically in all researched levels and settlements variated according to the depht in the cell due to mechanic factors and cell’s compounds. We concluded that the studied parameter influenced the settlements in the experimental cell.