International Journal of Mathematics and Mathematical Sciences
Volume 2007 (2007), Article ID 81519, 15 pages
doi:10.1155/2007/81519
An investigation on gas lift performance curve in an oil-producing well
Deni Saepudin1
, Edy Soewono1
, Kuntjoro Adji Sidarto1
, Agus Yodi Gunawan1
, Septoratno Siregar5
and Pudjo Sukarno6
1Industrial and Financial Mathematics Group, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
5Reservoir Engineering Group, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
6Drilling Engineering, Production, and Oil \& Gas Management Group, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
Abstract
The main objective in oil production system using gas lift technique is to obtain the optimum gas injection rate which yields the maximum oil production rate. Relationship between gas injection rate and oil production rate is described by a continuous gas lift performance curve (GLPC). Obtaining the optimum gas injection rate is important because excessive gas injection will reduce production rate, and also increase the operation cost. In this paper, we discuss a mathematical model for gas lift technique and the characteristics of the GLPC for a production well, for which one phase (liquid) is flowing in the reservoir, and two phases (liquid and gas) in the tubing. It is shown that in certain physical condition the GLPC exists and is unique. Numerical computations indicate unimodal properties of the GLPC. It is also constructed here a numerical scheme based on genetic algorithm to compute the optimum oil production.