| Summary: | In natural gas processing, vapour-liquid separation (VLS) is one of the commonly used unit
operations. In this paper, a series of Computational Fluid Dynamics (CFD) simulations were
conducted on an industrial scale VLS. Initially, simulations were carried out to evaluate the
performance of inlet diverter by studying the effect of inlet Reynolds number on the crosssectional
variance of velocity. It was found that the flow was highly symmetrical and evenly
distributed with a variance nearly zero at a very low Reynolds number (Re = 1000), but as the
inlet Reynolds number increased, the variance increased to 0.03 and the flow was highly
dominated towards the wall. To simulate the Knitmesh, porous media was used with inertial
and viscous resistance calculated and validated using previously published experimental data
(Rahimi and Abbaspour 2008).
When a full scale VLS was simulated, it was found that at industrially relevant condition the
effect of inlet diverter was significant on the Knitted mesh mist eliminator performance and
approx. 88% of it was subject to velocities above the prescribed terminal velocity and would
lead to poor vapor liquid separation. Without any hardware change to mitigate this
underperformance, it would be required to drop the capacity of the VLS by at least 5 times. On
the other hand, if two layers of mist pads with 75% size of full mesh pad was used, 26% recovery
in performance can be achieved.
The model proposed in this work provides the basis for future development of parametric study
on various configurations of mesh pad that can ultimately improve the capacity and
performance of the VLS.
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