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The advances in Electric Arc Furnace (EAF) dust treatment have been slowed down by high treatment costs and the large amount of residue to be processed and disposed. A process of direct separation and recovery of iron and zinc is now under development, which adds environmental and economical perspectives to the EAF dust treatment process. In this process, a coke bed filter can be directly connected to an EAF, collecting metallic iron and slag components, whereas the gas containing zinc and lead vapors flows to a zinc condenser. It results in zero amount of dust liberated to the environment. A two dimensional, axisymmetric and steady state mathematical model describing a coke fixed-bed filter is developed. The model solves coupled equations for gas-powder flow and is specifically applied in the investigation of over-micron and nano-scale powders (similar to EAF dust particle size) collection behavior. The theoretical model results are compared with the cold model experimental results, in which both injection of glass (over-micron) and silica (nano-scale) powders are considered. Microscopic observations and analysis are performed in order to describe better the injected powder behavior through the filter. EAF dust samples morphology is characterized as agglomerates of small particles. Its particle size distribution is obtained by the combination of leaching treatment and image analysis. Calculated results show that the powders particle size distribution has a direct effect in the static hold up. The model has been validated by its enough agreement for static hold up and pressure drop with experimental data from cold model experiments.KEY WORDS: mathematical model; Electric Arc Furnace; dust treatment; environment; packed bed; filter.have advanced for more detailed investigations, e.g. including the effect of the temperature, 23) the presence of an electrified field, 24) or the effect of the aerosol deposition on the filtration. 25) A model equation adapted from the theory for a fibrous filter, describing the dust load distribution in a coke bed filter, has also been recently developed and tested. 26)The aim of this research is contribute to the development and improvement of the process of direct separation and recovery of iron and zinc, testing and analyzing its efficiency and effectiveness. The physical modeling of the packed bed filter had provided a series of experimental results about pressure drop and the powder collection. [27][28][29][30][31][32] In this work a mathematical model of a cold coke fixed-bed filter has been developed. This model is used to investigate the powder accumulation behavior and pressure drop with the injection of over-micron and nano-scale powders in a packed bed. The mathematical model developed here is expected to be the framework for simulation of a high-temperature coke fixedbed filter and further on to study different aspects of this process. Microscopic Observations and AnalysisDue to lack of information about aerosol collection in packed bed filters, including the theoretical ...