The aim of this work consists in presenting a simple modelling easily usable in the industrial environment in order to predict the evolution of thermodynamical characteristics of the combustion of solid-gas mixtures in a closed vessel. In fact, very few studies have been interested in the association of agricultural dusts with a gaseous energetic Fuel (propane or methane) despite many dramatic consequences. Basic characteristics of modelling have been previously described to study cornstarch dust-air mixtures. A simple representation of the combustion phenomena based on energy transfers between particles and the action of specific molecules is given, The modelling adaptation to diphasic mixtures is carried out studying the fluctuations of the model parameters. The application conditions determine the fuel ratio of the used mixtures the adaptation of the chemical kinetics to the considered case and the calculation of the model parameters. The proposed development shows the model representativeness for a wide cornstarch concentration range (0.1 less than or equal to Delta less than or equal to 1kg/m(3)). It gives the possibility to analyse the supply of energetic gaseous substances (0 less than or equal to%C3H8 less than or equal to 6;0 less than or equal to% CH4 less than or equal to 12) and to study the fuel ratio of these two-phase mixtures for combustion times about 500 ms. The first results let appear correct tendencies in the predictions and it seems interesting to evaluate in the future the model adaptability to exclusively gaseous mixtures.