Ultra-deep sulfur-containing gas well shaft sulfur deposition treatment method

Abstract

The invention discloses an ultra-deep sulfur-containing gas well shaft sulfur deposition treatment method which comprises the following steps: injecting a sulfur solvent into a shaft to a sulfur deposition forming position in a small-displacement manner, closing the well for more than 2 days, opening the well to perform large-yield flow-back after the pressure of a wellhead rises, and collecting sulfur solvent residual liquid after reaction, so as to achieve sulfur deposition treatment. The method has the beneficial effects that the shaft pressure-temperature curve measured by the steel wire lowering pressure gauge and the intersection point of the gas well elemental sulfur precipitation and solidification phase diagram are used as the shaft sulfur deposition position, the volume of the shaft above the sulfur deposition position is used as the injection amount of the sulfur solvent, and the well is closed after oil pipe small-displacement injection and pump injection; then, large-displacement gas is discharged, and sulfur solvent residual liquid is injected by carrying a pump; sulfur deposition of the ultra-deep gas well is efficiently removed through sulfur deposition position calculation, low displacement, long soaking and large flow-back treatment processes.

Description

technical field [0001] The invention relates to the field of exploitation of oil and gas fields, in particular to a method for controlling sulfur deposition in well bores of ultra-deep sulfur-containing gas wells. Background technique [0002] The depth of ultra-deep sulfur-containing gas wells is greater than or equal to 5,000 meters. For gas wells with a depth of 6,000-7,000 m and a hydrogen sulfide content of more than 5%, it has the characteristics of ultra-deep and high sulfur content. At present, the wellbore pressure of some gas wells has dropped below 20 MPa, and the temperature has dropped to Below 30°C, in the later stages of production of ultra-deep sulfur-containing gas wells, the pressure, temperature, and production decrease, and the elemental sulfur in the acid gas is easy to precipitate and adhere to the wellbore, forming blockage and throttling, which affects the release of gas from the gas well. A physical or chemical method is required to melt in real time ...

AI Technical Summary

Problems solved by technology

[0010] The purpose of the present invention is to overcome the defects of the prior art such as high cost of sulfur deposition in ultra-deep sulfur-containing gas wells by solvent dissolution or heating and melting, and high risk of construction operations, and provide a method for controlling sulfur deposition in wellbore of ultra-deep sulfur-containing gas wells to achieve low Purpose of Cost-Effective Removal of Sulfur Deposition Problems in Ultra-Deep Gas Wells

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