(421ai) Prediction of Coalescence Rates for O/W Systems in Pipelines Using CFD

The estimation of coalescence rates in multiphase flow systems is a key factor to predict critical situations, in which phases start to separate. This can be guideline to control emulsion stability and to prevent unnecessary replacement in processes where O/W  dispersions are used. CFD studies exhibit attractive alternatives to predict increase of particles  size increase due to coalescence phenomena.

This study analyzes coalescence effect in a system oil/water (O/W) 10% oil, w/w , when hydrodynamic forces promote events in which two particles collide to give rise to new particles. In this work a method to analyze emulsion flow using CFD is presented. Flow conditions and size diameter are compared on instability of O/W dispersions in a pipeline with sudden enlargement. The results show strong effects of the coalescence efficiency on the mean Sauter diameter of droplets. The performance of each model  with respect to computational time and convergence is discussed.