In the current era, a major challenge facing the oil industry is to keep up production and maximize reserves especially in mature oil fields. The application of artificial lift systems to improve productivity, whilst ensuring the most effective use of existing reserves, should optimize the petroleum resources. However, the selection of the most feasible lift system plays a crucial role in restoring production rate to normal levels and to maximize ultimate recovery. The decision of which artificial lift method to use is very important to the long-term profitability of the field. This paper presents screening criteria on the different artificial lift techniques and discusses why the choice was confined to jet pumping as the most suitable technique applied in the well. Well–1A was spudded in November, 2008 and was drilled as a slanted well to the depth of 8665 ft. The well was completed with a sucker rod pumping unit and flowed initially at the rate of 130 BOPD. However, the well was optimized by changing the lift method from sucker rod to jet pump. The base development plan included hot crude injection with the help of water bath heaters, which made crude of 18 degree API and high wax content, heated up to 150°F used as power fluid for jet pumping. Both injection and return lines were insulated till the storage tank in order to maintain the temperature. The jet pump was run in hole with 11A Nozzle/Throat combination in freestyle after ensuring a sufficient liquid level within the wellbore. The jet pump provided the required drawdown and helped in sustaining the deliverability of the well for such waxy crude, and produced an average of 270 BOPD. Jet pump performance was monitored continuously in order to enhance the production up to desired potential by considering all the parameters related to the lift system. In addition to this, the jet pump can easily be re-optimized by reversing it out to change the nozzle and/or throat without requiring a slick-line job.
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