Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

Method for pressing low-pressure oil and gas well

A technology for oil and gas wells and low-pressure gas, which is applied in wellbore/well components, production fluids, earthwork drilling and production, etc. It can solve problems such as lost circulation, low pressure coefficient, and inability to implement effective well killing, and achieve less oil layer pollution and lower cost. Low, reliable plugging effect

Active Publication Date: 2014-05-07
PETROCHINA CO LTD
View PDF8 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a well killing method for low-pressure oil and gas wells to solve the problem of oil (gas) wells with low formation pressure coefficient and high gas production in the workover process. Problems with Effective Well Killing

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] A fire flooding production well using a low-pressure oil (gas) well killing method

[0019] (1) Well condition of the well

[0020] The well is a newly drilled production well in the fire flooding test area, with a depth of 550 meters, 7-inch casing and 27 / 8-inch tubing. Because the casing flange and the tubing at the casing head are punctured and leaked, the casing flange and casing need to be replaced. Valves on both sides of casing.

[0021] Before the workover, the gas composition and concentration data near the wellhead were detected on site, and the results are as follows:

[0022] CO:1128ppmH 2 S: 0ppm Combustible gas: 100ppm

[0023] Casing pressure: 0.4MPa Oil pressure: 0.2MPa Gas production: 900m 3 / d

[0024] (2) Implementation of workover

[0025] The kill fluid contains about 30m of 0.02% sodium hydroxide and 0.6% guar gum 3 , The oil-soluble temporary plugging agent is about 8Kg.

[0026] Well killing method: reverse circulation killing, fluid inje...

Embodiment 2

[0035] A low-pressure oil (gas) well killing method used in a fire flooding production test well

[0036] (1) Well condition of the well

[0037] The well is an old well that has undergone steam injection production and converted to fire flooding. The well is 570 meters deep and has a 7-inch casing. It is a double-pipe (both 23 / 8-inch tubing) well for production and testing in the test area. The main tube pump is used to pump oil. The auxiliary pipe is run into the test cable to monitor data such as downhole temperature and pressure. Due to the failure of the test instrument, it is necessary to inspect the pump and replace the test cable for the well. Before the workover operation, the wellhead data of the well were measured: wellhead casing pressure: 3.8MPa; CO: 933ppm; H 2 S: 66ppm, gas production 3500m 3 / d

[0038] (2) Implementation of killing wells

[0039] Killing fluid: about 30m containing 0.05% sodium hydroxide and 0.6% guar gum 3 , the oil-soluble temporary pl...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

Disclosed is a method for pressing a low-pressure oil and gas well. The method comprises the steps that firstly, alkaline guanidine gum liquid with the appropriate concentration and oil-soluble temporary plugging agents are prepared according to the well conditions (wellbore volume, gas production rate and the like); the oil-soluble temporary plugging agents and the guanidine gum liquid are mixed and then sufficiently and evenly stirred, and the temporary plugging agents are suspended in the guanidine gum liquid; the matched process, a ground pipeline and equipment are adopted to feed the mixture of the oil-soluble temporary plugging agents and the guanidine gum liquid into a stratum; the matched pipe column process is adopted to achieve the aims that the guanidine gum liquid with the temporary plugging agents can block and shield the stratum, leakage of well pressing liquid injected in a shaft is avoided, meanwhile, alkaline guanidine gum liquid has the better air-tight sealing performance and better safety for acid gas (hydrogen sulfide, carbon dioxide and the like), the shaft is filled with the alkaline guanidine gum liquid, the stratum gas is prevented from entering the shaft, it is ensured that well pressing succeeds, and the subsequent well repairing operation is facilitated. The method for pressing the low-pressure oil and gas well has the advantages that a near well zone nearby a shot hole is effectively blocked, the well pressing liquid is prevented from leaking, and entering the stratum, the stratum gas is prevented from entering the shaft, and it is ensured that the well repairing operation is smoothly carried out.

Description

technical field [0001] The invention relates to a well killing method in oil field workover operations, more specifically a well killing method suitable for low-pressure gas wells with low formation pressure coefficient and high gas production. Background technique [0002] The fire flooding mining technology adopted in the oil field is a method of oil recovery by injecting air through the combustion of the oil layer to generate heat, water vapor and flue gas drive. The flue gas produced from fire flooding production wells is mainly composed of nitrogen, carbon dioxide, and toxic and harmful gases such as hydrogen sulfide. Some production wells have a large gas volume (the maximum daily gas production can reach 5000m 3 above), and at the same time, the formation pressure coefficient is low (usually less than 1), well killing operations are difficult, lost circulation is prone to occur during conventional well killing operations, the gas invasion rate is fast, and it is diffi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): E21B33/13E21B43/22
Inventor 潘竟军胡承军彭辉王佳姚满仓
Owner PETROCHINA CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products