Stabilizing gas lift systems by reducing initial gas bubble sizes
6th International Conference on Petroleum Engineering
June 29-30, 2017|Madrid, Spain

Khalid M O Elmabrok, M L Burby and G G Nasr

University of Salford, UK

Posters & Accepted Abstracts: J Pet Environ Biotechnol

Abstract:

During oil production, gas lift methods can be affected by two-phase (gas and liquid) flow instability within the production tubing. This problem is caused by two main phenomena; the casing heading pressure and the flow perturbation due to the development of the flow regimes and its density wave oscillation. This paper presents a novel technique that reduces gas bubbles sizes, pressure drop long pipe and flow instability. A laboratory-scale two-phase flow experiment was designed and built to investigate the effects of flow perturbation and flow instability. The rig consisted of a 2 m long by 66 mm ID transparent PVC pipe, with an air injection point situated at 0.1 m above the base of the test section. The generated air bubbles within the two-phase flow were captured using a digital camera and the images were analyzed using an image processing package to obtain bubbles velocities, sizes and number long the test pipe. A novel air injection technique was then developed that reduced the overall bubbles sizes. As a result of this, the overall average air bubbles sizes were reduced by 22%, the big bubbles (Taylor bubbles) by 8.22%. In addition, the number of small bubbles was increased significantly and well distributed in the whole pipe area even near to the pipe wall (wall peaking), instead of (core peaking) the centre of the pipe. In comparison to (sharp edge) normal orifice gas lift valve with the same port size area and operating conditions, and also the lifting performance (production rate) was increased by 7.5%.

Biography :

Email: k.m.o.elmabrok.@edu.salford.ac.uk