The development of new reduction processes capable to use as raw materials mining and metallurgical residues, or based in cold agglomeration of self reducing mixtures (Fastmet, ITmk3, Tecnored) is regarded nowadays as an alternative to conventional processes, being the principal of these the blast furnace. In this context it becomes vital to analyze the behavior of processes operating with self-reducing agglomerates, as those utilizing the RHF and shaft furnaces. The present work aims at the development of a mathematical model capable to simulate the solid state reduction zone conditions of a shaft furnace (upper zone) that utilizes self-reducing agglomerates as the iron source. This model is capable of treating three phases, interacting simultaneously and transferring momentum, energy and mass. The set of phenomenological transport equations are treated through the finite volume method. The computational solution is achieved by the means of a software code developed in Fortran programming language and further, the graphical generation of the results, carried through the Tecplot program. The considered phases for the model are firstly the solid phase consisting in self-reducing agglomerates and a solid fuel (booster - added together with the agglomerate). Secondly, the gaseous phase, formed by a external gas, which constitutes on a set of gases that react in the external part of the agglomerates (mainly made out by the low gas - mixture of gases coming from the bottom part of the furnace, blended with the gases blew in the secondary level of tuyeres - V2), and a internal gas, another gaseous phase, consisting on the set of gases generated inside the self-reducing agglomerate as the result of a series of foreseen reactions. The model takes into account 25 reactions, amongst which are the reduction reactions, gasification of the coal, the combustions of coal, CO, volatiles, sulfur and polysaccharide and considering also the FeS formation. The model permitted the study of the V2 temperature, low gas temperature, low gas flow, agglomerate feed rate and wall heat lost influence on the process. The results, here graphically presented, are: solid, external gas and internal gas temperatures; reduction conditions in the gaseous atmosphere (CO in external gas, CO in internal gas, CO2 in external gas, CO2 of the internal gas); profile of pre-reduced iron oxides and Fe metallic and; distribution profile of the reduction degree. Moreover, operational parameters such as production, the residence time of solids, the volume of the gas phase, as well as its composition had been calculated by the model. From this information it was possible to compute the metallization, the volume, the temperature and the composition of the top gas. Those results confirmed that the computational simulation is a powerful tool for the shaft furnace operational parameters analysis.