Al-Rabiah, Danah, Al-Fulaij, Hala, and Ettouney, Hisham
Desalination & Water Treatment; September 2016, Vol. 57 Issue: 42 p19582-19595, 14p
AbstractThis study focuses on the development of design correlation for pressure drop in wire mesh demisters, used in the multistage flash desalination process (MSF) as well as similar evaporation and flashing units found in other industrial processes. Development of the correlation is based on numerical simulation of the demister using steady-state and two-dimensional model for the flow of vapor and brine droplets through the demister. An Eulerian model was used to model the system and the resulting model equations were solved using a commercial computational fluid dynamics software (FLUENT). The system model was formed of three zones, which include the vapor space above and below the demister and the demister. In addition, the demister was approximated as a porous media. A sensitivity analysis of the model revealed that vapor velocity, demister packing density and height, and the inlet flashed-off vapor composition are the main parameters that affect demister performance. Consequently, numerical data were used to correlate pressure drop across the demister as a function of operating and design parameters. The developed correlation was validated using data from real MSF plants. Analysis indicated that the correlation predictions and experimental data were consistent and showed good agreement with an error less than 25%.