Well Productivity Recovering Project in Tarim Oilfield
  • Background
    The gas well in this project were typical ultra-deep gas well with high temperature and pressures in the piedmont block of the Tarim Oilfield. Situations such as sand flow and well scaling were often observed during the production process at some gas wells, leading to blockage in the production string and greatly reduced productivity. Some wells had to be shut down as a result.
  • Challenges Faced by the Customer
    Challenges Faced by the Customer
    It was a 5,673-meter high-pressure gas well with surface temperature of 136°C and pressure of 105 MPa. The well was subject to a severe blockage in the production pipe and dramatically-decreasing outputs. And in February 2018, it was closed with a shut-in pressure of 11 MPa.
  • Our Solution
    Our Solution
    Aiming to revive the target well’s productivity, Jereh’s technology experts drew on their experience of unblocking ultra-deep high-pressure gas wells in the Tarim Oilfield. They created "a solution that used coiled tubing for sand washing and milling without removing the production string". However, it was rather complicated to operate in the target gas well. There are high risks of losing control and sticking of drill pipes, while the down-hole tools might not be able to work in an environment of ultra-depth, high temperature and corrosive gas. To overcome those negative factors, Jereh team chose a premium tool string in combination with reliable ground control systems, including the choke control valve, and de-sanding and filtering system, while using sand washing fluid with thermal-stability and low friction.
  • Values for the Customer
    Values for the Customer
    Our team completed the unblocking operation in only 3 days, and brought back the smooth production string without any blockage. After the operation, the gas well had its shut-in pressures increased from 11 MPa to 65 MPa, and the daily gas outputs up from 270,000 m³ (before the shut-in) to 490,000 m³. The daily oil outputs rose from 23 ton (before the shut-in) to 48 tons.