Major Innovation in Shale Gas Development Technology in Jilin Oilfield

Researchers from the Jilin Oilfield Oil and Gas Technology Research Institute tracked the recovery of corroded oil pipes in the southern Sichuan configuration area. In view of the complex corrosion environment of shale gas wellbores in southern Sichuan, researchers have developed a dual-control anti-corrosion plan for continuous injection of bactericidal corrosion inhibitors for shale gas. After the implementation of the plan, the bacterial content in the wellbore return fluid was less than 25 per milliliter, and the wellbore corrosion rate was less than 0.076 mm per year, providing support for ensuring the integrity of the wellbore.

Through experimental evaluation methods and combined with shale gas working conditions, researchers predicted the carbon dioxide corrosion rate of wellbore in different production stages, laying a theoretical foundation for the corrosion protection plan. In view of the superposition of multiple corrosion effects, a dual-control anti-corrosion plan with continuous injection of bactericidal corrosion inhibitors was formulated. Relying on the front-line test and detection platform in southern Sichuan, regular evaluation tests such as three-bacteria detection and bactericidal rate were carried out to ensure the implementation effect. In addition, researchers tracked the failure of oil pipes in depth on site, and identified corrosion factors through sampling and detection, inner and outer diameter measurement, corrosion rate evaluation, etc., to provide optimization basis for the subsequent implementation of wellbore corrosion protection plans.

In the next step, Jilin Oilfield will continue to promote the dual-control corrosion protection plan based on continuous injection of bactericidal corrosion inhibitors, study and optimize the dosing process for special on-site conditions, and promote the on-site application of the self-developed agent, further improve the efficient and low-cost corrosion protection plan, and ensure the integrity of shale gas wellbore in southern Sichuan.