Colloid dispersion polymer system and preparation method thereof

Abstract

The invention belongs to the technical field of oil exploitation, and particularly provides a colloid dispersion polymer system and a preparation method thereof. The preparation method comprises the following steps that 1, preparing a composite tackifying aid, specifically, adding a dispersing agent into dechlorinated tap water, and stirring to obtain a dispersing agent solution; and under a stirring condition, adding a crystal forming agent into the dispersing agent solution, and continuously stirring to obtain the composite tackifying aid; 2)preparing a polymer solution, namely adding polymer dry powder into high-calcium-magnesium oil field injection water, stirring until the polymer is fully dissolved, and filtering to remove insoluble substances to obtain the polymer solution; and 3)under a stirring condition, adding the composite tackifying aid into the polymer solution, and stirring until flocculate in the system is completely dispersed to obtain the colloid dispersed polymer system. By adding the composite tackifying aid, the interaction between calcium and magnesium ions and the polymer is changed, and the viscosity reduction effect of the calcium and magnesium ions is inverted into the tackifying effect, so that the viscosity of the polymer system is greatly improved, and the polymer system is uniform and stable.

Description

technical field

[0001] The invention belongs to the technical field of petroleum exploitation, and in particular relates to a colloid-dispersed polymer system and a preparation method thereof. Background technique

[0002] Polymer flooding is an important chemical flooding enhanced oil recovery technology. Polymer flooding technology is used in Class I and II reservoirs where the temperature is less than 80°C, the salinity is less than 30,000 mg / L, and the calcium and magnesium ion content is less than 400 mg / L. Has been fully industrialized application. However, due to the obvious molecular degradation of HPAM (partially hydrolyzed polyacrylamide) under high temperature conditions, its viscosity will drop significantly in oil reservoirs with high salinity, especially high calcium and magnesium ion content, and even precipitate and lose displacement. Oil capacity, the application of polymer flooding in high temperature and high salinity reservoirs has been greatly restricte...

Examples

preparation example Construction

[0020] The first aspect of the present invention provides a kind of preparation method of colloidal dispersion polymer system, and this preparation method comprises the following steps:

[0021] 1) Preparation of composite tackifier: add dispersant to dechlorinated tap water, stir to obtain dispersant solution; under stirring conditions, add crystal forming agent to dispersant solution, continue stirring to obtain composite tackifier;

[0022] 2) Prepare the polymer solution: add dry polymer powder into the injection water of the high-calcium-magnesium oil field, stir until the polymer is fully dissolved, filter to remove insoluble matter, and obtain a polymer solution;

[0023] 3) under stirring conditions, adding the composite thickening aid into the polymer solution, stirring until the flocs in the system are completely dispersed to obtain the colloidal dispersion polymer system;

[0024] The dispersant is one or more mixtures of homopolymers, copolymers, organic phosphonat...

Embodiment 1

[0039] A polymer flooding project is planned to be carried out in the high water cut period of a water injection development reservoir. The water quality of the injected sewage in the reservoir is 25g / L in total salinity, 1200mg / L in calcium and magnesium ion content, and the reservoir temperature is 62°C.

[0040] A kind of preparation method of colloid dispersion polymer system, this preparation method comprises the following steps:

[0041] 1) Preparation of compound viscosity-increasing aid: Add the dispersant sodium ethylenediamine tetramethylene phosphonate into dechlorinated tap water (fill tap water in the reaction kettle, stir for 2 hours and then store for more than 12 hours to obtain dechlorinated tap water) , adding a concentration of 2wt%, stirred for 10 minutes to obtain a dispersant solution; under stirring conditions, the crystal-forming agent Na 2 CO 3 Add to the dispersant solution, add the concentration of 3wt%, and continue to stir for 20 minutes to obtain...

Embodiment 2

[0046] A polymer flooding project is planned to be carried out in the high water cut period of a water injection development reservoir. The water quality of the injected sewage in the reservoir is 25g / L in total salinity, 1500mg / L in calcium and magnesium ion content, and the reservoir temperature is 62°C.

[0047] A kind of preparation method of colloid dispersion polymer system, this preparation method comprises the following steps:

[0048] 1) Preparation of composite tackifier: add the dispersant polymethacrylic acid to dechlorinated tap water (fill tap water in the reactor, stir for 2 hours and then store for more than 12 hours to obtain dechlorinated tap water), and add a concentration of 1.5wt %, stirred to obtain a dispersant solution; under stirring conditions, the crystal-forming agent NaHCO 3 Add it into the dispersant solution, add the concentration of 2wt%, and continue to stir to obtain the composite tackifier;

[0049] 2) Prepare polymer solution: use simulated...

technical field

[0001] The invention belongs to the technical field of petroleum exploitation, and in particular relates to a colloid-dispersed polymer system and a preparation method thereof. Background technique

[0002] Polymer flooding is an important chemical flooding enhanced oil recovery technology. Polymer flooding technology is used in Class I and II reservoirs where the temperature is less than 80°C, the salinity is less than 30,000 mg / L, and the calcium and magnesium ion content is less than 400 mg / L. Has been fully industrialized application. However, due to the obvious molecular degradation of HPAM (partially hydrolyzed polyacrylamide) under high temperature conditions, its viscosity will drop significantly in oil reservoirs with high salinity, especially high calcium and magnesium ion content, and even precipitate and lose displacement. Oil capacity, the application of polymer flooding in high temperature and high salinity reservoirs has been greatly restricte...

Examples

preparation example Construction

[0020] The first aspect of the present invention provides a kind of preparation method of colloidal dispersion polymer system, and this preparation method comprises the following steps:

[0021] 1) Preparation of composite tackifier: add dispersant to dechlorinated tap water, stir to obtain dispersant solution; under stirring conditions, add crystal forming agent to dispersant solution, continue stirring to obtain composite tackifier;

[0022] 2) Prepare the polymer solution: add dry polymer powder into the injection water of the high-calcium-magnesium oil field, stir until the polymer is fully dissolved, filter to remove insoluble matter, and obtain a polymer solution;

[0023] 3) under stirring conditions, adding the composite thickening aid into the polymer solution, stirring until the flocs in the system are completely dispersed to obtain the colloidal dispersion polymer system;

[0024] The dispersant is one or more mixtures of homopolymers, copolymers, organic phosphonat...

Embodiment 1

[0039] A polymer flooding project is planned to be carried out in the high water cut period of a water injection development reservoir. The water quality of the injected sewage in the reservoir is 25g / L in total salinity, 1200mg / L in calcium and magnesium ion content, and the reservoir temperature is 62°C.

[0040] A kind of preparation method of colloid dispersion polymer system, this preparation method comprises the following steps:

[0041] 1) Preparation of compound viscosity-increasing aid: Add the dispersant sodium ethylenediamine tetramethylene phosphonate into dechlorinated tap water (fill tap water in the reaction kettle, stir for 2 hours and then store for more than 12 hours to obtain dechlorinated tap water) , adding a concentration of 2wt%, stirred for 10 minutes to obtain a dispersant solution; under stirring conditions, the crystal-forming agent Na 2 CO 3 Add to the dispersant solution, add the concentration of 3wt%, and continue to stir for 20 minutes to obtain...

Embodiment 2

[0046] A polymer flooding project is planned to be carried out in the high water cut period of a water injection development reservoir. The water quality of the injected sewage in the reservoir is 25g / L in total salinity, 1500mg / L in calcium and magnesium ion content, and the reservoir temperature is 62°C.

[0047] A kind of preparation method of colloid dispersion polymer system, this preparation method comprises the following steps:

[0048] 1) Preparation of composite tackifier: add the dispersant polymethacrylic acid to dechlorinated tap water (fill tap water in the reactor, stir for 2 hours and then store for more than 12 hours to obtain dechlorinated tap water), and add a concentration of 1.5wt %, stirred to obtain a dispersant solution; under stirring conditions, the crystal-forming agent NaHCO 3 Add it into the dispersant solution, add the concentration of 2wt%, and continue to stir to obtain the composite tackifier;

[0049] 2) Prepare polymer solution: use simulated...