This thesis studies a submerged membrane bioreactor (MBR) technology that is used to treat effluents. We present in detail the modeling of this process, the validation of developed models, and the results of simulation and optimization carried out with the above mentioned models. The new contributions to scientific knowledge of this work are the following: - A new dynamic model that integrates for such systems, many of the variables and the main phenomena occurring during the process of filtration in MBR wastewater treatment. That constitutes an original contribution to the analysis and development of this technology. – The simulation allows to achieve the quantification of the influence and effect of aeration on the process (membranes fouling) and the influence of the sequencing of the filtration and coarse bubbles aeration cycles. All that takes into account the behavior of biomass, the generation of exopolymeric substances and inlet characteristics. The results provided by the model are validated by comparison with experimental results. – An optimization of MBR operating conditions using the experimental design for simulation, is reported based on the results obtained using the developed model