Characterisation of municipal solid waste physical properties and their evolution with age

This paper presents results of the physical characterisation of municipal solid waste (MSW) through laboratory and in situ tests, as well as by a monitoring system. The physical parameters of MSW characterised are: particle size distribution, geometry and classification of the waste, moisture and organic matter content, unit weight, and temperatures of the landfilled waste. The results are part of research carried out in the Sto Tirso landfill (in the north of Portugal) between 2001 and 2007. The results obtained from different analysis methods are compared. The influence of the average age of the deposited MSW and of the landfill phase (construction and post-construction) on the parameters is also presented. Regression models are presented for the decay of total and degradable organic matter, and for the influence of overburden stress on MSW unit weight, plus correlations obtained between some of the analysed parameters.