Population Balance Modeling for Integrating Hydrodynamics with Electrostatics in Crude Oil Electrocoalescers

Document Type : Research Paper


Petroleum Refining and Processing Technology Development Division, Research Institute of Petroleum Industry, Tehran, Iran


A particular population balance model (PBM) which consists of hydrodynamic and electrostatic parts is developed for electrocoalescence of distributed water droplet in the continuous oil phase. The approach is the modification of a recognized PBM by adding the electrostatic effects on the overall coalescence rate including the number of times (frequency) occurring collision and the efficiency of coalescence. Moreover, the modified model has been being implemented in a CFD-PBM problem for a pilot plant electrocoalescer to predict the profile of water phase and size distribution of droplets. The results recognize the effect of local electric field intensity and local water content on electrocoalescence rate. Furthermore, the results demonstrate that separation for the very small droplets (<4μm) is minor, for the medium sizes (8-32μm) is more considerable, and for larger droplets (>64μm) occurs completely. Ultimately, by making a comparison between the simulation results and the pilot data, the EHD PB model is validated.


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