Municipal waste landfills represent not only a source of landfill gases, but a source of thermal energy as
well. The heat in landfills is generated by physical, chemical and microbiological processes. The goal of
our study was to characterize the thermal properties of municipal solid waste (MSW) samples of the
given landfill. A new apparatus was designed and constructed to measure heat flow. A systematic test
series of 17 discrete measurements was carried out with municipal waste samples of 1.0–1.7 m3
. The
thermal conductivity, heat diffusivity and specific heat capacity of the samples were determined.
Analysing the results of the sampling and our experiments it was realized that the theoretical fundaments
should be clarified. Two theories were developed for the serial and for the parallel heat flow in
three phase disperse systems. The serial and parallel models resulted in different theoretical estimations.
The measured thermal conductivity and heat diffusivity were better characterized by the parallel
heat flow estimations. The results show that heat can flow parallel in solid, liquid and gas phases.
Characterization of thermal properties serves to establish the fundament of heat extraction from
municipal waste landfills.