New Technologies in Artificial Lift and Well Completions Applied in the Extraheavy Crude Oilfields in PDVSA Eastern Division

摘要

New technologies were developed associated with modifications of different subsurface components, all of these were oriented to handle more efficiently and at lower costs the ESP's (electric submersible pumps) equipment, which were adversely affected by: high viscosity of the crude oil and high gas content at the intake of the pump and solids content (sand) The evaluation and standardization of new technologies based on the experienced learned trough the years, allowed production increments per well between 20- 40%, electric consumption reduction over 40% and a smaller equipment came out as a result. This paper shows the basis of design and behavior of the conventional and improved ESP's equipment, the new technologies developed for lifting with ESP's and producing economically this heavy crude oil in reservoirs under the bubble point pressure. Some of the improvements include the use of tapered pumps and capillary tubes for gas handling purposes. PDVSA San Tome along with a local manufacturer, have developed two different types of completion that have reduced cost and increase production while making the down hole completion operations simpler and faster. Intelligent Completion. This type of completion was designed to be able to complete multiple production zones trough a single well bore, taking care of the need to monitor and control the production of each one of the zones individually as required by Venezuelan government. After using mechanical models for cyclic steam injection packers, a 100% hydraulic unit called CB- TIET was designed and more than sixty units were installed, obtaining significant savings on rig time (20000 $/well) and allowing five days of early production. Likewise, Injector-Producer packer and steam injection ports were tried to improve the steam distribution throughout the horizontal section of a well located at the Bare Oilfield. Finally technologies were developed for progressive cavity pumps and sucker rod pump optimization systems which included expert software combined with variable speed drives and load cells that allows the optimization system to take it's own decision according to the behavior of the well obtaining an overall production increment of 25% per well after the installation of these devices.