Artificial Lift

Deviated wells have now been the standard form of drilling, increasing well life and production but also creating challenges in the Artificial Lift System, specifically the Reciprocating Rod Lift (RRL). With aggressive drilling deviations rod string guiding becomes a requirement, landing pumps in 45+° zones a normal, and gas mitigation a complete necessity to achieve target productions. 

In the past 10 years, drilling methods have drastically reduced the time it takes to drill wells. This is especially true in today’s unconventional shale market where 20,000 ft wells are being drilled in under 14 days. This increase in drilling rates along with increasing depths and deviations has presented many challenges for the conventional rod lift system, which was designed to last for ten years but are now having issues within the first twenty-four months resulting in substantial increases in workover costs.

One requirement of a Class VI Underground Injection Control permit involves continuous monitoring and reporting of injection pressure. Wells in pilot and commercial scale carbon dioxide (CO2) storage sites are equipped with devices that measure pressure and flow rate during injection operations. Downhole device failures have occured during CO2 injection operations in projects, which prevent bottom hole pressure measurement and require time consuming repairs.

Two widely used methods of artificial lift are Electrical Submersible Pumps (ESP) and Sucker Rod Pumps (SRP. Each of these methods frequently require methods to avoid or handle gas for successful operations. Presented here are discussions of methods of gas separation for each method and graphical techniques for prediction of the gas separator performance that will allow the user to better select a workable gas separator system and predict maximum well drawdown with the selected method of lift. 
 

It is recognized in the industry that it is wise to have AL in place before liquid loading is expected for a number of reasons.  These reasons include no production loss when the well drops below critical, convenience as the rig may/may not be available when the well drops below critical later, and in some cases some uplift is observed when installing plunger other AL before the rate drops below a calculated predicted critical. The discussion here concerns installing plunger lift in deviated wells in advance of predictions from well-known methods that say the well is not liquid loaded.

In unconventional wells unstable dynamic behavior ensuing from an exchange of energy in the casing and tubing is the biggest challenge in gas lift design. As reservoir and tubing pressures decline from early conditions, wells show erratic behavior in decreasing fluid levels and hence unload and operate at variable depths. This case study presents the full workflow of creating an effective gas-lift design from concept initiation to execution and field installation.

Contemporary lift strategy for a newly completed well generally includes a period of unassisted flow followed by an Electrical Submersible Pump (ESP) system - up to half a dozen in certain situations. This is followed by one of a multitude of artificial lift options often culminating in a rod lift strategy for low-production to end of life. Ignoring entirely the financial component of these decisions, among the primary drivers of lift type selection is maximum uplift capability – an area in which rod lift has seen significant investment and improvement in recent years.

Lessons Learned with Jet Pumps in a Low Pressure Gassy and Sandy Reservoir with High Deviation The jet pump is said to be a flexible tool adaptable to produce where other artificial lift methods have shortcomings: however, it too requires special considerations in search of economics and life cycle optimization. This report reviews design and equipment upgrades to the jet pump system with solutions and continued shortcomings after one year of operation.

Carbon fiber sucker rods were first installed in wells in 2015, and significant material and design improvements have been made since. Originally developed to rod pump the deepest wells with small-diameter tubing, high-strength, light-weight carbon fiber rods are optimal for rod pumping through the build section in pad-drilled wells. This paper will show how carbon fiber rods reduce friction and side-wall loads through wellbore deviations, and enable higher ESP-like rates of production when operated with long stroke beam pumping units.
 

This paper proposes an analytical methodology that consists of an evaluation of the particle size distribution, viability for the use of sand screens and centrifugal separation systems for sand control management in wells with high sand and fluid production producing through an ESP. All the technical considerations are explained focusing on the information required and the parameters analyzed to recommend the most accurate design for sand control; selected approaches and models that have been developed to improve the runtime due to sand issues.