عنوان مقاله [English]
this work, agitated slurry-bubble reactor was simulated with the aid of computational fluid dynamics techniques. The effects of impeller flow direction on hydrodynamic behavior and the aeration quality of reactor spargers (terephthalic acid CTA, production in Shahid Tondgooyan petrochemical complex) were investigated. To this aim, an Eulerian multiphase approach and RNG k-ε turbulence model were employed for large-scale CFD simulations. The results showed that up-flow impeller caused an increase in bubble residence time and mixing intensity in the higher zones of the reactor. Therefore, the length of the liquid path and the number of direction changes were greater in the case of up-flow impeller compared to down-flow one. As a result, the energy associated with the down-flow impeller (at the bottom of reactor) was much higher than the up-flow one; hence the turbulence intensity for the down-flow impeller was also relatively high. For down flow pattern, the outlet gas of spargers caused a reverse flow by the liquid flow and pushed the gas to the reactor center.
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