Investigating the performance of the high-pressure flare of Pars Chenoubi Fifth Refinery and the factors affecting its performance using CFD simulation

In this research, the CFD simulation of the high-pressure flare (HP) of the 5th South Pars Refinery was carried out in industrial dimensions in order to evaluate the effects of the geometrical parameters of the flare type on the combustion characteristics of the flare (flame shape and position). The CFD model was developed considering all transport phenomena (momentum, heat, mass transfer, radiation, turbulence and chemical reactions). In order to avoid numerical errors, proper meshing was done. The results of the developed calculation model include the temperature and velocity profile (shape and nature of the flame), the concentration profile of the gas species sent to the furnace, as well as the species profile of the combustion products. The results of CFD simulation show that in the HP Flare, in the operational status, the increase in the temperature of the Flare tip due to the impact of the flame is negligible, so its performance is suitable with the current amount of sweep gas. Therefore, the further reduction of the gas sent to the HP flare is not justified because the flame may be drawn into the flare network, or due to the very low height of the flame and the ambient wind speed, the surface temperature of the flare tip and wind shield may increase, which in the long run time will cause the destruction of the surface of the flare tip and its total replacement. If the wind speed is higher than usual (strong local winds), the return of the flame inside the flare tip should be controlled with the amount of fuel gas.