Application of Gas Lift Technology to a High-Water-Cut Heavy-Oil Reservoir in Intercampo Oilfield, Venezuela

摘要

This paper presents successful applications of gas lift technology to heavy-oil reservoirs in Intercampo oilfield, Lake Maracaibo, Venezuela. Liquid production rates range from 10 to 320 m~3/day per well. Gas lift was selected as the first artificial lift method in the oilfield. The paper describes the gas lift mechanisms applied in a high-water-cut heavy-oil (below 15 API) reservoir. The theoretical analysis showed that the injection gas rate for gas lift and the gas/oil ratio (GOR) of an oil well have direct effects on the fluid flow from the wellbore. Theoretical design and actual gas lift production are described in the paper. The correlations used for artificial gas lift design for high-water-cut heavy oil need to be refined to match the field data. The difference between theoretical design and actual production is significant for high-water-cut heavy oil lower than 15 API. Formation of oil/water emulsion was not observed during gas lifting of low-API, high-water-cut oil from wells. In this study, a correction coefficient for gas lift design was applied to a high-water-cut, low-API field. Further work is needed to refine this gas lift design software. It should prove particularly useful for production engineers in optimizing the design of gas lifting equipment.