Testing practice of heavy oil artificial lift in Well E-1 of a block in West Africa

Deepwater heavy oil testing is usually done by artificial lift means using electric submersible pump and gas lift. Considering the characteristics of deepwater heavy oil reservoir in a block of Congo (Brazzaville) and the failure to perform sophisticated testing design due to extremely scarce information, the surfacedriven screw pump is selected as the artificial lift means based on the in-depth research on the reservoir characteristics, the physical properties of crude oil, and the operating environment of the formation to be tested. Finally, the testing process perforating gun + sand liner + DST + screw pump coupling is adopted and viscosity reduction measures such as cable heating and insulation of insulating tubing inside the hollow sucker rod are taken to successfully overcome the difficulties caused by heavy oil, sand production, and deepwater low temperature for the testing. Satisfactory results are ultimately achieved and the technology provides a useful reference for the testing of similar blocks.