Publications

In recent years, gas flaring has become a major issue and has made various countries and industries commit to “zero routine flaring” by 2030. Recovery of gas flaring becomes a challenge in a mature offshore facility located at West Java offshore, Indonesia. A vent recovery unit had been installed to recover flaring gas. However, its application may not be preferable due to the higher energy needed and potential physical hazard exposure to personnel and facility, such as high noise and vibration during operation. A solution that emerges to recover a substitute vent recovery unit regarding flaring gas recovery is the application of an ejector. This paper discusses the fast, cheap, and applicative modeling approach to design an absolute vacuum ejector that is reliable to recover flare gas, reduce emission, and deliver unused gas as an additional sales gas. Enhanced ejector configuration with “extended vacuum entrainment” (EVE) is designed under computational fluid dynamic (CFD) modeling. This approach is applied to determine the optimum turbulence, diffusion, and generating EVE phenomenon attracting low energy secondary flux up to atmospheric conditions. The CFD is performed under the green-gauss finite volume method with a cell-centered formulation which aims to achieve as low as reasonably practicable convective-diffusive coefficient using equations of turbulent kinetic energy (k) and rate of dissipation of turbulent kinetic energy (ε). Simulation results showed EVE occurred in several vacuum positions such as: primarily at the motive nozzle exit, secondarily at the diffusion chamber, and tertiary at the throat zone. EVE has been proven in resulting optimum primary-secondary stream flow ratio ranging from 0.12 to 0.45, absence of vortex occurrence, and energy efficiency up to 82%. During 8 months of operation, this solution has successfully attracted 6.6 MMSCF equals to reduced CO2 emissions by 447 tons. To be aligned with sustainable energy efficiency and conservation programs, enhanced-ejector is denominated as a green-low-cost solution.