Process for performing well completion by utilizing biological completion fluid

Abstract

The invention discloses a process for performing well completion by utilizing biological completion fluid, which comprises the following steps of: preparing biological enzyme aqueous solution; preparing biological acid aqueous solution; sequentially squeezing or mixing and squeezing the biological enzyme aqueous solution and the biological acid aqueous solution into a well by using a tubing high-pressure water jet device after perforation; and finally closing the well for 24 to 72 hours, washing boreholes after pressure diffusion, and performing a cyclic filling and sand prevention process. As de-plugging and scale formation prevention are combined and physical measures and chemical measures are combined, the process has the advantage of fulfilling the aims of effectively improving the permeability around the well, the production efficiency of an oil well, the yield and the recovery ratio at the premise of protecting oil pools.

Description

technical field [0001] The invention relates to a well completion process in oilfield development, in particular to a well completion process using biological well completion fluid. Background technique [0002] According to the connection between the production layer and the wellbore and the structure of the bottom hole, the completion methods can be divided into: open hole completion, perforation completion, liner completion, gravel packing completion, etc. Damage and the constraints of the formation itself have caused many production wells to fail to achieve the expected results. In addition to drilling factors, many times it is because the completion of wells is not done in a suitable way, resulting in low production efficiency and very uneconomical, and some wells even become dead wells due to pollution. [0003] The current water-based completion fluids are mainly solid-free clean brine completion fluids and solid-free polymer glues. The main components are water-solu...

AI Technical Summary

Problems solved by technology

Although these completion fluid systems can achieve low damage to the reservoir through a lot of work, and the technical parameters meet the requirements of reservoir protection, but it cannot relieve and overcome the original damage of the reservoir: such as various macromolecular treatment agents in the Adsorption, retention and accumulation in the reservoir; incompatibility between various operating fluids and formation water; incompatibility between various operating fluids and reservoir minerals: perforation is difficult to remove deep damage caused by liquid phase and treatment agents; Perforation is difficult to remove the solid plugging in the vertical direction between pores; after open hole completion or workover operations, it is difficult to remove deep damage by oil flow itself; It can damage the permeability of the reservoir core to 30% to 50%, and cannot further improve the reservoir to achieve the purpose of increasing production of oil wells