Investigating the Performance of the LPG Flare of the Fifth South Pars refinery Using CFD Simulation and Providing a Solution

Document Type : Original Article

Authors
Mohammad Irani
Yaghoub Behjat
Scientific Faculty Member, Gas Research Division, Research Institute of Petroleum Industry (RIPI), Postal Code: 1485613111, Tehran, Iran
Abstract
In this research, the simulation of the LPG flare of South Pars Refinery in industrial dimensions was carried out in order to investigate the effect of the flare tip geometry on the combustion characteristics of the flare, including the shape and position of the flame, using CFD technique. In order to prevent numerical errors, a suitable hybrid grid was used. The results of the developed model (CFD) include the temperature and velocity profile, the concentration profile of the components of the gases sent to the flare, as well as the concentration profile of the components of the combustion products. The results of CFD simulation show that in the LPG flare in operating conditions, in some points of the flare tip, the increase in the temperature of the flare tip body (523-350 °C) due to the direct impact of the flame is significant in a limited way. Therefore, the performance of the flare in operating conditions is not suitable with the current amount of sweeping gas. With the continuation of this process and the increase in the surface temperature of the flare type body, it will eventually lead to its complete destruction and replacement. Therefore, the amount of sweep gas injected into the flare should be increased to improve the combustion performance. In addition, due to the presence of sectional gusts and the increase in wind speed up to 110 km/h, the effect of sectional gusts on the performance and combustion characteristics of the LPG flare was investigated. The results of the CFD model showed that the flame deviation in the direction of the wind direction is high and as a result the flame is drawn into the flare tip and the temperature of the gas seal and the flare tip body and the wind shield increases up to 850°C and finally to Complete destruction of the wind shield. In order to avoid such dangers (when the wind is strong), the fuel gas injection should be adjusted to a level to prevent the flame from returning to the flare tip.

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Subjects

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  • Receive Date 11 March 2024
  • Revise Date 23 April 2024
  • Accept Date 15 May 2024