Tuesday, January 22, 2008
Display problem ? Click HERE
There are many young design engineer will experience or has experienced gas - liquid separator sizing. In most cases, a mist eliminator is used to trap small liquid droplet entrained in the gas. Now the engineer may experience difficulties in answering the following questions :
- What type of mist eliminator (e.g. mesh pads, vane pack, etc) should be used ?
- What are the advantages and disadvantages of mesh pad and vane pack ?
- How mesh pads and vane pack trap liquid droplet ?
- What is the liquid capture efficiency of mesh pad and vane pack ?
- How droplet size, mesh strand diameter, gas velocity, liquid density, gas density, gas viscosity, mesh pad/vane pack design affecting liquid capture efficiency ?
- What is the limit of mesh pad compare to vane pack ?
- How do i size mesh pad or vane pack mist eliminator ?
- What are the geometry and installation requirement of separator with mist eliminator ?
Although this article may assist you in determining the type of mist eliminator, dimension, mist eliminator thickness, gas flow area, etc using a recommended design Souders-Brown vapor load factor (K), however there are still many other type of mist eliminator (MistFix insertion mist eliminator, double-pocket vane pack, which potentially result better removal efficiency and cost effective as compare to ordinary mesh pads and vane pack. In addition, the graph is tested with air-water mixture, it may have some deviation with actual process fluid. The deviation could be insignificant or very significant.
You may use above proposed method for PRELIMINARY sizing in order to get a quick separator dimensioning, the detail selection and calculation shall be conducted by mist eliminator supplier with their proprietary graph and correction parameters.
In many real world examples, the mist eliminator thickness would be in the range of 4"-6". Thus, you may use this PRELIMINARY thickness in quick separator dimensioning.
- AMISTCO (P2) - Extensive info on Mist eliminator, knitted mesh, random & structured packing, distillation
- AMISTCO (P1) - Extensive info on Mist eliminator, knitted mesh, random & structured packing, distillation
- KnitMesh...Good Articles on Mist eliminator still available FREE...
- ACS - Design manual for Mist Eliminators, Trays, Packing, Internals...All in distillation columns
Any comments / advices ?..........Drop it in comment field (below) or send a private email to me...