Elastic gel temporary plugging well killing fluid used in combination with gas well and construction process

Abstract

The invention relates to an elastic gel temporary plugging well killing fluid used in combination with a gas well and a construction process. The elastic gel temporary plugging well killing fluid comprises 1 # elastic gel and 2 # elastic gel, wherein the 1 # elastic gel comprises the following components in parts by weight: 1.5-3 parts of a temperature-resistant and salt-resistant polymer, 1.0-1.5parts of an organic cross-linking agent, 4-6 parts of an inorganic toughening agent, 0.2-0.5 parts of a stabilizer and 100 parts of water, and the 2 # elastic gel comprises the following components in parts by weight: 2-5 parts of a temperature-resistant and salt-resistant polymer, 1.0-1.5 parts of an organic cross-linking agent, 0.2-0.5 parts of a stabilizer and 100 parts of water. After the combined elastic gel temporary plugging well killing fluid is gelatinized, the pressure resistance is greater than or equal to 20MPa, and the theoretical filtration loss is less than 200mL / h, the performance stabilization time is longer than 30 days, the adsorption retention in places such as stratums and wellbores is effectively reduced while the high pressure bearing capacity is ensured, and the technical requirements for temporary plugging leakage prevention and reservoir protection of gas wells with relatively low stratum pressure coefficients are met.

Description

technical field [0001] The invention relates to the technical field of natural gas development, in particular to an elastic gel temporary plugging and killing fluid used in combination for gas well workover and a construction process. Background technique [0002] Workover operation is one of the important means to maintain the normal production of gas wells. During the production process of gas wells, sand production in the formation, dirt precipitation, blow-by of production strings, tubing breakage, water flooding of gas wells, etc. will lead to abnormal production of gas wells. In addition, casing deformation, corrosion, rupture, tubing corrosion and perforation, breakage, tubing blockage and other reasons will also cause gas wells to stop production or even be scrapped. In order to keep these gas wells in a good production state, it is necessary to carry out workover operations on them to restore normal production. [0003] There are two main methods of workover for g...

AI Technical Summary

Problems solved by technology

[0009] In order to solve the problem that the old gas wells in carbonate reservoirs have been produced for a long time, due to the low reservoir pressure coefficient and the unclear development of acid-dissolved pores / fractures, there are problems in the workover process, such as large volume of conventional workover fluid and resumption of production. Long period, poor controllability of strong gel, difficult gel breaking, high cost of villi, poor passability of solid phase particles, easy jamming and other problems. The purpose of the present invention is to provide a temporary plugging of elastic gel used in combination with gas wells. Killing fluid and construction technology to realize temporary plugging of old gas wells in carbonate reservoirs, reduce reservoir damage, and restore gas well productivity in time