Publications

One of the most important decisions at initial startup planning is whether to flow newly completed wells initially to the rig or to the floating facility. Completion and stimulation fluids returned during the initial well cleanup are corrosive and are difficult to treat. The flowback fluids may also contain solids from the reservoir and from construction debris which may cause problem such as erosion to the subsea equipment and the swivel. Particulate material to be removed from a wellbore can have a vast range in size, shape and density. Typical solid materials in Abadi Field are mainly consisting of formation sand, cement, fluid loss pill, and gun debris. The characteristic of the particles (size, shape and density), carrier liquid (density, viscosity) and operation parameters of pipe flow (velocity, pipe diameter, solid concentration) greatly influence their dynamic behavior in flowing media. This paper presents the flowback analysis study by calculating the terminal settling (critical) velocity of each material and investigates using OLGA software whether the gas velocity is sufficient and operationally accepted to clean up all of the solid particles. Terminal velocity, drag and gravity forces and shear stresses are affected by particle properties and the rheology of the flowing fluid. The flowpath of the fluid from the wellbore up to the topside Floating LNG (FLNG) consists of horizontal and vertical path. At the horizontal path, the fluid velocity shall exceed the critical deposition velocity, whereas at the vertical flowpath, the fluid velocity shall exceed the terminal settling (critical) velocity. The entrained solid particles in multiphase fluids separated either at the drilling rig or the floating facility (Abadi FLNG), are also investigated. The result shows that the two options, flow back to drilling rig and to the Abadi FLNG, shall be carried out. The flowback to the drilling rig is designated to cleanup all of the completion fluids and some solid particle. Meanwhile, perforating gun debris has to be transported through Abadi FLNG with some proper mitigation plan.