Study on drilling and completion technology of multigas combined production branch wells

Natural gas hydrates are pure, pollution-free, widely dispersed, and have a lot of potential as clean energy. However, due to the shallow burial depth of natural gas hydrate reservoirs, the reservoir is non-diagenetic argillaceous sandstone, and the borehole stability is poor, which poses a huge challenge for safe and efficient exploration. This article studies the drilling and completion technology of multi-gas commingled production branch wells with the aim of three-gas commingled production in order to address these issues. In order to drill and complete branch wells, the lateral window opening and branch hole reentry technologies are examined, and a field construction plan is created. The upper part of branch wells enables re-entry into the main and branch holes. A whipstock system is used in a single drilling operation to complete both window opening, grinding, and milling tasks. In this technical scheme, the integrated guide recovery module of the process string is added, which is important for achieving the goal of three-gas combined production. It can reduce the number of independent trips, reduce the three trips of a single well, improve the operational efficiency by more than 20%, and lower the operating cycle and operating cost.