阅读说明：本技术 超分子凝胶堵漏浆及其制备方法 (Supermolecular gel leakage-stopping slurry and preparation method thereof ) 是由 *** 李鹏程 梁培杰 王晓军 许朋琛 余大洲 刘天峰 滑志超 夏珮然 于 2020-07-15 设计创作，主要内容包括：本发明提出一种超分子凝胶堵漏浆及其制备方法,属于钻井液技术领域。所述凝胶堵漏浆由包括如下重量份数原料制备而得：凝胶堵漏组分2-8份、结构剂8-20份；其中,所述凝胶堵漏组分包括聚二乙基二烯丙基氯化铵、氯化钠、聚戊双烯酰胺、水一。该超分子凝胶堵漏浆主要用于钻井时封堵漏失层,具有堵漏效果好,流变性好等特性。(The invention provides supermolecular gel leakage-stopping slurry and a preparation method thereof, belonging to the technical field of drilling fluids. The gel leakage-stopping slurry is prepared from the following raw materials in parts by weight: 2-8 parts of a gel plugging component and 8-20 parts of a structuring agent; wherein the gel plugging component comprises poly diethyl diallyl ammonium chloride, sodium chloride, polypentadiene amide and water I. The supermolecule gel leakage-stopping slurry is mainly used for stopping a leakage layer during drilling, and has the characteristics of good leakage-stopping effect, good rheological property and the like.)

1. The supramolecular gel leakage-blocking slurry is characterized by being prepared from the following raw materials in parts by weight: 2-8 parts of a gel plugging component and 8-20 parts of a structuring agent; wherein the gel plugging component comprises poly diethyl diallyl ammonium chloride, sodium chloride, polypentadiene amide and water I.

2. The gel lost circulation slurry of claim 1,

in the gel plugging component, the mass ratio of poly diethyl diallyl ammonium chloride to sodium chloride to poly pentadiene amide to water I is 0.05-0.2: 1-10: 1-5: 100.

3. gel plugging slurry according to claim 1 or 2,

in the gel plugging component, the mass ratio of poly diethyl diallyl ammonium chloride, sodium chloride, polypentadienamide and water I is 0.09: 5: 2: 100.

4. the gel lost circulation slurry of claim 1,

the structural agent is formed by mixing rigid particles, deformable particles and mineral fibers.

5. A gel leakage blocking paste according to claim 4,

the mass ratio of the rigid particles to the variable particles to the mineral fibers is 50: 30: 20.

6. the gel lost circulation slurry of claim 1,

the supermolecule gel leakage-stopping slurry also comprises water II.

7. The gel plugging slurry as claimed in claim 6, which is prepared from the following raw materials in parts by weight: 2-8 parts of gel plugging component, 8-20 parts of structuring agent and 70-80 parts of water II.

8. The preparation method of the supramolecular gel leakage blocking paste as claimed in any one of claims 6 to 7, characterized by comprising the following steps:

mixing water I, poly diethyl diallyl ammonium chloride, sodium chloride and poly pentadiene amide to obtain a gel plugging component; adding a second water and mixing; adding a structuring agent to obtain the supermolecule gel plugging slurry.

Technical Field

The invention belongs to the technical field of drilling fluid, and particularly relates to supermolecular gel plugging slurry and a preparation method thereof.

Background

In the development process of an oil field, leakage is common, well leakage causes underground accidents such as overflow, well collapse, drill sticking and the like, and well drilling safety and construction progress are seriously influenced. The leakage situations are various, for example, the upper stratum is cemented loosely, the connectivity is better, and the permeability leakage is the main one; the secondary system is mainly composed of mudstone, and has a low cracking pressure, so that the use of high-density mud is likely to cause the loss of the laminated crack.

Engineering technicians are constantly dedicated to research the leakage prevention and stoppage of easily-leaked strata. For example, CN109762540A discloses a supramolecular plugging agent, which is composed of a supramolecular polymer and a supramolecular structuring agent, and the supramolecular plugging agent has good dispersibility, can be quickly and uniformly mixed with an aqueous solution, has good viscoelasticity and plugging property, is not easy to be diluted by water mixing, and can adapt to leakage strata with different pore and fracture properties. CN109705829A discloses a pressure-bearing leaking stoppage slurry, which comprises bentonite, a fiber material, a supramolecular polymer, a filling material, a reinforcing agent, an elastic material, a rigid material, a delayed expansion agent and the balance of water, and can realize the purposes of plugging a leaking layer and improving the pressure-bearing capacity of a stratum.

Disclosure of Invention

The invention provides a supermolecule gel plugging slurry and a preparation method thereof.

The invention provides supermolecular gel leakage-stopping slurry which is prepared from the following raw materials in parts by weight: 2-8 parts of a gel plugging component and 8-20 parts of a structuring agent; wherein the gel plugging component comprises poly diethyl diallyl ammonium chloride, sodium chloride, polypentadiene amide and water I.

Further, in the gel plugging component, the mass ratio of poly diethyl diallyl ammonium chloride, sodium chloride, polypentadienamide and water I is 0.05-0.2: 1-10: 1-5: 100.

further, in the gel plugging component, the mass ratio of poly diethyl diallyl ammonium chloride, sodium chloride, polypentadiene amide and water I is 0.09: 5: 2: 100.

further, the structural agent is formed by mixing rigid particles, deformable particles and mineral fibers.

Further, the mass ratio of the rigid particles, the variable particles and the mineral fibers is 50: 30: 20.

further, the supramolecular gel leakage blocking slurry also comprises water II.

Further, the composition is prepared from the following raw materials in parts by weight: 2-8 parts of gel plugging component, 8-20 parts of structuring agent and 70-80 parts of water II.

The invention also provides a preparation method of the supramolecular gel leakage-stopping slurry, which comprises the following steps:

mixing water I, poly diethyl diallyl ammonium chloride, sodium chloride and poly pentadiene amide to obtain a gel plugging component; adding a second water and mixing; adding a structuring agent to obtain the supermolecule gel plugging slurry.

The invention has the following advantages:

the invention provides a supermolecular gel leakage-stopping slurry, wherein gel leakage-stopping components mainly comprise poly diethyl diallyl ammonium chloride (SD-2), sodium chloride and poly pentadiene amide (SD-1), the SD-1 and the SD-2 form a three-dimensional network structure in a solution through the action of covalent bonds, and a surrounding medium can be cemented into a firm whole in a leakage layer to form a high-strength supermolecular aggregate. The sodium chloride mainly plays a role in viscosity reduction, and is matched with a structural agent to realize synergistic effect, so that the finally formed leakage blocking slurry forms a gel slug with enough viscosity, shearing force, elasticity and static structure in a leakage layer within a controllable time. Because of the extremely strong adhesive force and strength, the high flow resistance can be formed finally to resist the damage of external force (leakage pressure difference), thereby realizing the successful sealing of the leakage layer. And moreover, due to the introduction of special functional groups in the supramolecular polymer, the gel leakage-blocking slurry has good rheological property at room temperature, and a leakage layer is easy to block.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 shows a plugging slurry obtained in example 1 of the present invention.

Figure 2 shows the gelled plugging paste obtained in example 1 of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The embodiment of the invention provides supramolecular gel leakage-blocking slurry which is prepared from the following raw materials in parts by weight: 2-8 parts of a gel plugging component and 8-20 parts of a structuring agent; wherein the gel plugging component comprises poly diethyl diallyl ammonium chloride (SD-2), NaCl, poly pentadiene amide (SD-1) and water I.

The gel plugging component of the supermolecule gel plugging slurry provided by the embodiment of the invention mainly comprises SD-1, SD-2 and NaCl, wherein the SD-1 and the SD-2 form a three-dimensional network structure (shown in a route I) in a solution through the action of a covalent bond, and a surrounding medium can be cemented into a firm whole in a leakage layer to form a high-strength supermolecule aggregate. NaCl mainly plays a role in viscosity reduction, and meanwhile, the NaCl is matched with a structural agent to realize the synergistic effect, so that the leakage-stopping slurry forms a gel slug with enough viscosity, shearing force, elasticity and static structure in a leakage layer within a controllable time. The high-strength plugging agent has extremely strong adhesive capacity and strength, and can finally form high flow resistance to resist the damage of external force (leakage pressure difference), thereby realizing the successful plugging of a leakage layer.

Route I.

In one embodiment of the invention, the mass ratio of the poly diethyl diallyl ammonium chloride, the NaCl, the polyprenyl amide and the water I is 0.05-0.2: 1-10: 1-5: 100.

in a preferred embodiment of the invention, the mass ratio of the poly-diethyl diallyl ammonium chloride, the NaCl, the polypentadienamide and the water I is 0.09: 5: 2: 100.

in a preferred embodiment of the present invention, the molecular weight of SD-2 is 10 to 20 ten thousand. The molecular weight of SD-1 is 1500-2500 ten thousand.

In one embodiment of the invention, the structural agent is formed by mixing rigid particles, deformable particles and mineral fibers. Wherein the rigid particles are mainly granules with hardness, and specifically can be quartz sand, walnut shells, shell powder and the like. The deformable particles are mainly expandable and softenable particles, and may be rubber particles in particular. The mineral fiber is mainly various mineral fibers, and specifically can be aluminum silicate fiber and the like. The structural agent of the embodiment of the invention forms a supporting framework structure in the gel network system, so that the stress can be uniformly distributed through the inorganic framework material when the system is stressed, therefore, the supporting framework structure is formed in the gel network system formed by the components of the leakage plugging slurry of the embodiment of the invention, so that the stress is uniformly distributed when the system is stressed, the strength of the gel is improved, the resistance to leakage pressure difference is improved, and the leakage sealing strength is further improved.

Preferably, the mass ratio of the rigid particles, the deformable particles and the mineral fibers is 50: 30: 20. the three components are mixed according to a certain proportion, so that the obtained gel leakage-stopping slurry is more stable.

In further embodiments, suitable structurants may have a particle size of: when the leakage rate of the drilling fluid is less than or equal to 5 square/hour, the particle size of the structuring agent is less than or equal to 1 mm;

when the leakage rate of the drilling fluid is 5-10 square/hour, the grain diameter of 30 wt% of the structuring agent is less than or equal to 1mm, and the grain diameter of 70 wt% of the structuring agent is 1-3 mm;

when the leakage rate of the drilling fluid is 10-30 square/hour, the particle size of 5 wt% of the structuring agent is 1-3mm, and the particle size of 95 wt% of the structuring agent is 3-5 mm;

when the drilling fluid loses the return property and leaks, the grain diameter of 10 wt% of the structuring agent is 3-5mm, and the grain diameter of 90 wt% of the structuring agent is 5-8 mm.

Wherein, for rigid particles and variable particles, the particle size is measured; for mineral fibers, the length is measured as the particle size.

Specifically, when the gel plugging is carried out, the particle size of the structural agent is matched according to the leakage speed of the drilling fluid. Because different particle size matching is carried out according to different leakage characteristics, bridging is carried out in the leakage plugging process, and the strength is improved, thereby meeting the requirements of plugging different types of leakage layers.

The embodiment of the invention also provides the supermolecular gel leakage-stopping slurry, which also comprises water II. It is pointed out that the second water in the supermolecular gel plugging slurry can also be replaced by the well slurry on the premise of not influencing the final performance of the plugging slurry.

Specifically, the feed additive is prepared from the following raw materials in parts by weight: 2-8 parts of gel plugging component, 8-20 parts of structuring agent and 70-80 parts of water II. In the supermolecule gel plugging slurry, the higher the content of gel plugging components and a structuring agent is, the higher the strength of the formed colloid is, the smaller the formation pores are, and the higher the bearing pressure is.

The embodiment of the invention also provides a preparation method of the supramolecular gel leakage-stopping slurry, which comprises the following steps:

mixing water I, poly diethyl diallyl ammonium chloride, NaCl and poly pentadiene amide to obtain a gel plugging component; adding a second water and mixing; adding a structuring agent to obtain the supermolecule gel plugging slurry.

It should be noted that in the embodiment of the present invention, the first water and the second water may be the same water.

The supermolecule gel plugging slurry can be directly used for a leakage layer. Specifically, the use method of the gel plugging slurry comprises the steps of directly pumping the supermolecule gel plugging slurry into a leakage layer, standing at the temperature of 60-120 ℃ for gelling, and standing for gelling for about 4-8 hours. The higher the strength of the formed gel along with the increase of time, the better the plugging effect on the formation pores and fractures.

The present invention will be described in detail with reference to examples.