A water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-bearing gas reservoir

Abstract

The invention relates to a water blocking method for establishing a large-area chemical partition at the gas-water interface of a gas reservoir with water, including: (1) injecting a water-phase solution into the gas-water interface of the gas reservoir, and the water-phase solution plays the role of diffusion and dispersion Migrate downward to the water layer; (2) Inject the oil phase solution into the gas-water interface of the gas reservoir, and the oil phase solution spreads on the gas-water interface, replacing the gas-water interface with the oil-water interface; (3) The water phase monomer diffuses to the oil layer , in the oil-water interface close to the oil phase, the polymerization reaction occurs with the oil phase monomer to form a microporous polymer interlayer; (4) formation water penetrates into the polymer interlayer under the action of pressure difference, and mineral ions and impurities continue to Scale is deposited on the polymeric barrier to form a water-impermeable polymeric barrier. The invention is reliable in principle and easy to operate, can effectively solve the problems of small plugging range and low plugging strength in commonly used water shutoff systems in the process of water invasion control of edge-bottom water gas reservoirs, and has great significance for efficient exploitation of edge-bottom water gas reservoirs. Practical significance.

Description

technical field

[0001] The invention relates to the field of oil and gas field development, in particular to a water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-containing gas reservoir. Background technique

[0002] The energy of the water body in the edge-bottom water gas reservoir is huge. If reasonable water control measures are not taken during the development process, the gas reservoir is extremely vulnerable to water intrusion, and there will be edge water advancement, bottom water coning, and bottom water ridge ingress, resulting in water breakthrough in the gas well. , thereby reducing the gas recovery rate.

[0003] For water intrusion in gas reservoirs, profile control and water shutoff, production rationing and water control, and drainage and gas recovery are three commonly used means of water control in gas reservoirs. Among them, production rationing and water control can delay the water breakthrough ti...

Examples

Embodiment 1

[0048] A water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-containing gas reservoir, comprising the following steps in sequence:

[0049] (1) Prepare 100ml of an aqueous solution with a mass fraction of 3% m-phenylenediamine, and adjust the pH to 11 with NaOH solution;

[0050] (2) Prepare 100ml of a cyclohexane solution with a mass fraction of 0.5% 1,3,5-trimesoyl chloride, and add 0.5ml of octylphenol polyoxyethylene ether (OP-10) and stir evenly;

[0051] (3) Take 10ml of the water phase solution and inject it from the bottom of the sand filling pipe until the water phase solution reaches the middle of the sand filling pipe; then inject 5ml of the oil phase solution from the top of the sand filling pipe and wait to spread to form a polymer interlayer (For the plugging performance evaluation process, see figure 2 ), after two minutes of reaction, put the sand-filled tube into a 60°C oven to fully carry out the polym...

Embodiment 2

[0057] A water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-containing gas reservoir, comprising the following steps in sequence:

[0058] (1) Prepare 100ml of an aqueous solution of polyethyleneimine (PEI) with a mass fraction of 2% and a relative molecular mass of 600, and adjust the pH to 11 with NaOH solution;

[0059] (2) prepare 100ml mass fraction and be the cyclohexane solution of 0.5% 1,3,5-trimesoyl chloride, and add 0.5ml polyethoxytrisiloxane (ethoxy modified polytrisiloxane ) stir evenly;

[0060] (3) Take 10ml of the water phase solution and inject it from the bottom of the sand filling pipe until the water phase monomer reaches the middle of the sand filling pipe to establish the air-water interface; then inject 5ml of the oil phase solution from the top of the sand filling pipe and wait Spread to form a polymer interlayer (see the plugging performance evaluation process for figure 2 ), after two minute...

technical field

[0001] The invention relates to the field of oil and gas field development, in particular to a water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-containing gas reservoir. Background technique

[0002] The energy of the water body in the edge-bottom water gas reservoir is huge. If reasonable water control measures are not taken during the development process, the gas reservoir is extremely vulnerable to water intrusion, and there will be edge water advancement, bottom water coning, and bottom water ridge ingress, resulting in water breakthrough in the gas well. , thereby reducing the gas recovery rate.

[0003] For water intrusion in gas reservoirs, profile control and water shutoff, production rationing and water control, and drainage and gas recovery are three commonly used means of water control in gas reservoirs. Among them, production rationing and water control can delay the water breakthrough ti...

Examples

Embodiment 1

[0048] A water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-containing gas reservoir, comprising the following steps in sequence:

[0049] (1) Prepare 100ml of an aqueous solution with a mass fraction of 3% m-phenylenediamine, and adjust the pH to 11 with NaOH solution;

[0050] (2) Prepare 100ml of a cyclohexane solution with a mass fraction of 0.5% 1,3,5-trimesoyl chloride, and add 0.5ml of octylphenol polyoxyethylene ether (OP-10) and stir evenly;

[0051] (3) Take 10ml of the water phase solution and inject it from the bottom of the sand filling pipe until the water phase solution reaches the middle of the sand filling pipe; then inject 5ml of the oil phase solution from the top of the sand filling pipe and wait to spread to form a polymer interlayer (For the plugging performance evaluation process, see figure 2 ), after two minutes of reaction, put the sand-filled tube into a 60°C oven to fully carry out the polym...

Embodiment 2

[0057] A water shutoff method for establishing a large-area chemical partition at the gas-water interface of a water-containing gas reservoir, comprising the following steps in sequence:

[0058] (1) Prepare 100ml of an aqueous solution of polyethyleneimine (PEI) with a mass fraction of 2% and a relative molecular mass of 600, and adjust the pH to 11 with NaOH solution;

[0059] (2) prepare 100ml mass fraction and be the cyclohexane solution of 0.5% 1,3,5-trimesoyl chloride, and add 0.5ml polyethoxytrisiloxane (ethoxy modified polytrisiloxane ) stir evenly;

[0060] (3) Take 10ml of the water phase solution and inject it from the bottom of the sand filling pipe until the water phase monomer reaches the middle of the sand filling pipe to establish the air-water interface; then inject 5ml of the oil phase solution from the top of the sand filling pipe and wait Spread to form a polymer interlayer (see the plugging performance evaluation process for figure 2 ), after two minute...

Images