SEPARATOR

Separation of Heterogeneous mixtures which Heterogeneous mixtures consist of two or more phase (part) which have different compositions that do not react chemically. The separation can be done physically by the differences in the density between the phases such as: gas-liquid, gas-solid, liquid-liquid, liquid-solid and solid-solid. Separator vessels can be classified based on its functions: 1) Two phases separator:  Gas/ vapor-liquid separator, Liquid-liquid separator, Gas – solid separator, and Liquid – solid separator and 2) Three phases separator :Gas-liquid-liquid separator.


Gas – Liquid Vertical Separator Basic Philosophy, A vertical separator drum is a vertical vessel into which a liquid and vapor mixture (or a flashing liquid) is fed and wherein the liquid is separated by gravity, falls to the bottom of the vessel, and is withdrawn. The vapor travels upward at a design velocity which minimizes the entrainment of any liquid droplets in the vapor as it exits the top of the vessel. The size a vapor-liquid separator drum (or knock-out pot, or flash drum, or compressor suction drum) should be dictated by the anticipated flow rate of vapor and liquid from the drum. The drum should have a vapor outlet at the top, liquid outlet at the bottom, and feed inlet at somewhat above the half-full level. At the vapor outlet, provide a de-entraining mesh pad within the drum such that the vapor must pass through that mesh before it can leave the drum. Depending upon how much liquid flow you expect, the liquid outlet line should probably have a level control valve.


Vertical Separator Sizing

where:
V = maximum allowable vapor velocity, m/sec
ρL = liquid density, kg/m3
ρG = vapor density, kg/m3
k = 0.107 m/s (when the drum includes a de-entraining mesh pad)
where: A = the cross-sectional area of the drum, m2 Q = vapor flow rate, m3/sec D = the drum inside diameter, m Selected Inside diameter = D + 2 x clearance m Clearance for demister installation is normally 50 m.