CONTINUOUS GAS LIFT OPTIMIZATION WITH A NOVEL GENETIC ALGORITHM

9th International Multidisciplinary Scientific GeoConference - SGEM2009, www.sgem.org, SGEM2009 Conference Proceedings/ ISBN 10: 954-91818-1-2, June 14-19, 2009, Vol. 1, 587-594 pp

ABSTRACT

In continuous gas lift, gas may be injected continuously or intermittently, depending on
the producing characteristics of the well and the arrangement of the gas-lift equipment.
Being somehow an ancient tool with an age of over a century, gas lift is though still a
challenging problem when overall optimization is the concern. When the injection gas is
of a limited supply the problem is finding the best gas allocation scheme. However there
are increasingly emerging cases in certain geographic localities where the gas supplies
are usually unlimited. The optimization problem then totally travels to the wellbore and
completion string and fully engages with multiphase flow concepts. In the present study
an intelligent genetic algorithm has been developed to simultaneously optimize all
effective factors namely, gas injection rate, injection depth and tubing diameter towards
the maximum oil production rate with the water cut and injection pressure as the
restrictions. The computations and real field data are mutually compared.

Keywords: gas lift, optimization, depth of injection, gas injection rate, tubing size