Numerical simulations and optimization of separation efficiency of gas-liquid two-phase flow in flare knock-out drum

Knock-out drum in the flare system can avoid rain of fire because it can effectively separate droplets or solid impurities from the vent gas and reduce the amount of condensate in the gas. Therefore, knock-out drum plays a key role for the safety of the flare system and the protection of the environment. In the paper, FLUENT software was applied to simulate the effect of droplet diameter, the pressure difference between the inlet and outlet, working temperature, liquid holdup of the gas and length-diameter ratio on separation efficiency of horizontal knock-out drum. The results showed that properly increasing the droplet diameter, working temperature and length-diameter ratio of knock-out drum, decreasing the pressure difference of the inlet and outlet, liquid fraction can benifit to increase the separation efficiency of the knock-out drum.