阅读说明：本技术 一种防漏失钻井液材料及其使用方法 (Leakage-proof drilling fluid material and using method thereof ) 是由 黄熠 李炎军 罗鸣 张万栋 韩成 张超 彭巍 李文拓 曾春珉 于 2021-10-20 设计创作，主要内容包括：本发明公开了一种防漏失钻井液材料及其使用方法。本发明的防漏失钻井液材料,包括如下重量份的组分：钻井液100份,柔性剂1～3份,防漏剂4～6份,增强剂2～8份,所述防漏剂由弹性石墨、纤维材料、油溶树脂、多孔材料、碳酸钙、石英砂、核壳类粒子和植物果壳颗粒组成；所述增强剂为平均粒径800～1500μm的塑料颗粒,具有类球体、正四面体、正八面体、正十二面体中的至少三种形态。本发明通过柔性剂、防漏剂和增强剂,协同作用,在钻井过程中实现主动防御-主动强化-强制强化的连续增强过程,具有高抗压、高抗剪切性能,有效避免了深层钻井过程出现了漏失情况。(The invention discloses a leakage-proof drilling fluid material and a using method thereof. The leakage-proof drilling fluid material comprises the following components in parts by weight: 100 parts of drilling fluid, 1-3 parts of a flexibilizer, 4-6 parts of a leak preventer and 2-8 parts of a reinforcing agent, wherein the leak preventer consists of elastic graphite, a fiber material, oil-soluble resin, a porous material, calcium carbonate, quartz sand, core-shell particles and plant shell particles; the reinforcing agent is plastic particles with the average particle size of 800-1500 mu m, and has at least three forms of a spheroid, a regular tetrahedron, a regular octahedron and a regular dodecahedron. The invention realizes the continuous strengthening process of active defense, active strengthening and forced strengthening in the drilling process through the synergistic effect of the flexibilizer, the leak preventer and the reinforcing agent, has high compression resistance and high shear resistance, and effectively avoids the leakage condition in the deep drilling process.)

1. The anti-leakage drilling fluid material is characterized by comprising the following components in parts by weight:

100 parts of drilling fluid, 1-3 parts of flexibilizer, 4-6 parts of leak preventer, 2-8 parts of reinforcing agent,

the leak preventer comprises elastic graphite, a fiber material, oil-soluble resin, a porous material, calcium carbonate, quartz sand and core-shell particles;

the reinforcing agent is plastic particles with the average particle size of 800-1500 mu m, and has at least three forms of a spheroid, a regular tetrahedron, a regular octahedron and a regular dodecahedron.

2. The loss prevention drilling fluid material of claim 1, wherein the drilling fluid is a water-based drilling fluid or an oil-based drilling fluid.

3. The fluid loss control material of claim 1, wherein the flexibilizing agent is one or more of bitumen, a low thermoplastic material, or paraffin.

4. The loss prevention drilling fluid material of claim 1, wherein the average particle size of the loss prevention agent is 800 μm or less.

5. The leak-proof drilling fluid material as claimed in claim 1, wherein the resilient graphite has a resilience of 40% or more at 52MPa for 30min and a resilience of 60% or more at 30MPa for 30 min.

6. The fluid loss additive material of claim 1, wherein the reinforcing agent comprises a first particle size plastic particles having an average particle size of D1 e [800 μm, 1000 μm ], a second particle size plastic particles having an average particle size of D2 e (1000 μm, 1200 μm ], and a third particle size plastic particles having an average particle size of D3 e (1200 μm, 1500 μm).

7. The leak-proof drilling fluid material as claimed in claim 6, wherein the mass ratio of the first, second and third plastic particles is 3-4: 2-3: 1 to 2.

8. The loss prevention drilling fluid material of claim 1, wherein when the reinforcing agent is a regular tetrahedron, the length of the regular tetrahedron is less than or equal to 1500 μm; when the reinforcing agent is an octahedron, the length from any vertex of the octahedron to other vertices is less than or equal to 1500 μm; when the reinforcing agent is a regular dodecahedron, the length from any vertex of the regular dodecahedron to other vertices is less than or equal to 1500 mu m.

9. The loss prevention drilling fluid material of claim 1, wherein the plastic particles have a heat distortion temperature of 190 ℃.

10. The method of using the fluid loss prevention material as claimed in any of claims 1 to 9, comprising the steps of:

s1, uniformly mixing drilling fluid and a flexibilizer, adding a leak-proof agent, drilling, and continuously supplementing the leak-proof agent in a circulation process according to the number of vibrating screens;

s2, supplementing a reinforcing agent according to the stratum leakage condition, and continuously drilling:

leak rate<0.0001m³Supplementing 2 parts by weight of first particle size reinforcing agent when in the hour;

the leak rate is 0.0001 to 5m³And when the particles are used for per hour, 3-4 parts by weight of a first particle size reinforcing agent, 2-3 parts by weight of a second particle size reinforcing agent and 1-2 parts by weight of a third particle size reinforcing agent are supplemented.

Technical Field

The invention relates to the technical field of oil field drilling fluid, in particular to a leakage-proof drilling fluid material and a using method thereof.

Background

With the change of land and marine oil and gas resource development from shallow layer to deep layer of more than 5000m, the super-layer drilling fluid technology of over 5000m is rapidly developed. Meanwhile, the well leakage problem in the deep drilling process also occurs. Compared with shallow drilling, the deep drilling is affected by high temperature and high pressure, the well leakage problem occurs more frequently, the repeated leakage times are more, and the drilling efficiency is greatly affected. The leak-proof method for shallow drilling is difficult to be applied to deep drilling.

The existing anti-leakage method mainly comprises two modes: (1) the common drilling fluid is matched with a leakage-proof material to prevent leakage; the Chinese patent application CN105062440A discloses a leakage-stopping and leakage-preventing material, which improves the leakage-preventing effect of the stratum through fibers, polymer microspheres, polymer powder, blast furnace slag and the like, but a large amount of fibers are quickly concentrated under the pressure difference effect to cause the phenomenon of sealing a door by a pore or a micro-crack opening, the strength of the polymer microspheres and the slag is also high, and the effective leakage-preventing effect is difficult to be achieved under the condition of the stratum with high temperature and high pressure; (2) the Chinese patent application CN105199685A discloses a water-based drilling fluid for leak-proof and leak-stopping of induced fractures, which provides a plugging scheme while drilling by utilizing polymer gel plugging agent, bridge plug plugging agent, rubber particles, unidirectional pressure plugging agent, sawdust, mica, vermiculite and other particles, but the particles have poor adaptability to fractures and gaps, and are difficult to have long-term stable high-pressure-bearing and high-shear-resistant performance in a long open hole section of a high-temperature and high-pressure stratum.

Therefore, it is necessary to develop a material for preventing the leakage of drilling fluid, which can be effectively used for preventing the leakage while drilling in deep drilling.

Disclosure of Invention

The invention aims to overcome the defect of poor leakage prevention effect of deep drilling in the prior art, and provides a leakage prevention drilling fluid material, which realizes the continuous reinforcement process of active defense, active reinforcement and forced reinforcement in the drilling process through the synergistic action of a flexibilizer, a leakage prevention agent and a reinforcing agent, has high compression resistance and high shear resistance, and effectively avoids the leakage occurrence in the deep drilling process.

The invention also aims to provide a use method of the anti-leakage drilling fluid material.

In order to solve the technical problems, the invention adopts the technical scheme that:

a leakage-proof drilling fluid material comprises the following components in parts by weight:

100 parts of drilling fluid is mixed in the drilling fluid,

1-3 parts of a flexibilizer,

4-6 parts of a leakage-proof agent,

2-8 parts of a reinforcing agent,

the leak preventer consists of elastic graphite, a fiber material, oil-soluble resin, a porous material, calcium carbonate, quartz sand and core-shell particles;

the reinforcing agent is plastic particles with the average particle size of 800-1500 mu m, and has at least three forms of a spheroid, a regular tetrahedron, a regular octahedron and a regular dodecahedron.

In the leakage-proof drilling fluid material, the flexibilizer can fill part of micropores and micro-crack formations generated during drilling; the leak-proof agent can cover most of pores and microcracks within the range of 0-800 mu m, and the air intensity formed by the cooperative matching of the leak-proof agent and the drilling fluid is ensured to have a good elastic deformation space through the compounding of various materials such as elastic graphite, the shear resistance is excellent, and the leak-proof agent can have good adaptability under a multi-pressure system of a high-temperature and high-pressure stratum; the reinforcing agent is plastic particles with various forms, particle embedding of weak stratums is achieved, filling and supporting capacity of parts prone to instability is improved, strength is improved, meanwhile, the fact that the anti-leakage agent and the flexibilizer can enter the weak parts in the drilling process is guaranteed, a stable plugging area is formed, and anti-leakage effect is achieved.

Preferably, the drilling fluid is a water-based drilling fluid or an oil-based drilling fluid.

Preferably, the oil-based drilling fluid has an oil-water ratio of not less than 4.

Preferably, the oil in the oil-based drilling fluid is 5# white oil and/or 0# diesel oil.

Preferably, the water-based drilling fluid is one or more of a polymer drilling fluid, a polymer potassium chloride (Plus/KCl) drilling fluid, or a strongly inhibited polyamine (HEM) drilling fluid.

Preferably, the flexibilizer is one or more of asphalt, low thermoplastic material or paraffin.

The low thermoplastic material is polyvinyl acetate or rigid polyvinyl chloride.

The low thermoplasticity ensures the granular or liquid filling type plugging of the filtrate seepage passage under different temperature forms, and can strengthen the low water loss wall building property of the drilling fluid.

Preferably, the low thermoplastic material has an average particle size of 500 μm or less.

Preferably, the asphalt is emulsified asphalt or sulfonated asphalt.

When the drilling fluid is an oil-based drilling fluid, emulsified asphalt can be matched; when the drilling fluid is water-based, sulfonated asphalt can be matched.

Preferably, the average particle size of the leak preventive is less than or equal to 800 μm.

Preferably, the resilience rate of the elastic graphite is more than or equal to 40% under the conditions of 52MPa and 30min, and the resilience rate is more than or equal to 60% under the conditions of 30MPa and 30 min.

The resilience rate of the elastic graphite is detected according to a JB/T9141.4-2013 standard method.

Preferably, the fibrous material is at least five of kapok fiber, silk fiber, flax fiber, coconut fiber, asbestos fiber, polyvinyl alcohol fiber, polyacrylonitrile fiber, or metal fiber.

Preferably, the oil-soluble resin comprises a brittle oil-soluble resin and/or a plastic oil-soluble resin.

Optionally, the brittle oil-soluble resin may be one or more of oil-soluble polystyrene, modified phenolic resin and dimerized abietic acid.

Optionally, the plastic oil-soluble resin may be one or more of amino resin, acrylic resin and nitro resin.

Preferably, the average pore diameter of the porous material is 50-100 nm, and the density of the porous material is 1.8-2.4 g/cm³。

Preferably, the porous material is one or more of metal fiber felt, silica aerogel, open-cell rubber or activated carbon.

Preferably, the calcium carbonate is calcium carbonate with different particle sizes of 100 meshes, 200 meshes, 400 meshes, 800 meshes, 1500 meshes and 2500 meshes according to a mass ratio of 1: (0.8-1.2): (0.8-1.2): (0.8-1.2): (0.8-1.0): (0.6-0.8).

Preferably, the quartz sand is modified by a silane coupling agent.

Preferably, the shell of the core-shell particle is polymethyl methacrylate, and the core is acrylated polyurethane.

Preferably, the leakage preventive further comprises plant husk particles.

More preferably, the plant husk particles are walnut shell particles and/or cottonseed shell particles.

Preferably, the reinforcing agent consists of plastic particles with a first particle size and an average particle size of 800-1000 μm, plastic particles with a second particle size and an average particle size of 1000-1200 μm (excluding 1000 μm), and plastic particles with a third particle size and an average particle size of 1200-1500 μm (excluding 1200 μm).

Preferably, the mass ratio of the first-particle-size plastic particles to the second-particle-size plastic particles to the third-particle-size plastic particles is 3-4: 2-3: 1 to 2.

Preferably, when the reinforcing agent is a regular tetrahedron, the length of the regular tetrahedron is less than or equal to 1500 mu m; when the reinforcing agent is an octahedron, the length from any vertex of the octahedron to other vertices is less than or equal to 1500 μm; when the reinforcing agent is a regular dodecahedron, the length from any vertex of the regular dodecahedron to other vertices is less than or equal to 1500 mu m.

Preferably, the heat distortion temperature of the plastic particles is more than or equal to 190 ℃.

Preferably, the plastic particles are one or more of polyetherimide, polybenzimidazole and polyamide imide.

Preferably, the reinforcing agent is prepared by the following method:

and (3) performing injection molding on the plastic by using spherical, regular dodecahedral, regular octahedral and regular tetrahedral molds with different sizes to obtain the plastic particles with the shapes of a sphere, a regular tetrahedron, a regular octahedron or a regular dodecahedron.

Preferably, the leak preventer is prepared by the following method:

mixing elastic graphite, fiber material, oil soluble resin, porous material, calcium carbonate, quartz sand, core-shell particles and plant shell particles (if any) uniformly.

The invention also provides a use method of the anti-leakage drilling fluid material, which comprises the following steps:

s1, uniformly mixing drilling fluid and a flexibilizer, adding a leak-proof agent, drilling, and continuously supplementing the leak-proof agent in a circulation process;

s2, supplementing a reinforcing agent according to the stratum leakage condition, and continuously drilling:

leak rate<0.0001m³Supplementing 2 parts by weight of first particle size reinforcing agent when in the hour;

the leak rate is 0.0001 to 5m³And when the particles are used for per hour, 3-4 parts by weight of a first particle size reinforcing agent, 2-3 parts by weight of a second particle size reinforcing agent and 1-2 parts by weight of a third particle size reinforcing agent are supplemented.

The inventor researches and discovers that in the normal drilling process, a first particle size reinforcing agent with the particle size of 800-1000 mu m is added under the condition that the drilling fluid is normally lost; in the presence of drilling fluid of 5m³After the small discharge capacity within/h is lost, adding a reinforcing agent with compound particle size, and circulatingAnd continuing to supplement and enhance within the range of 2-4 h according to the leakage condition. According to the method, in the process of deep drilling, the continuous strengthening process of active defense, active strengthening and forced strengthening is carried out in the weak area of the well wall of the high-temperature and high-pressure stratum, and a compact inner and outer mud cake plugging area is formed in the easy-to-leak structure, so that the leakage condition is effectively avoided.

Preferably, in step S1, the leakage preventive is added in an amount of 2 to 3 parts by weight per hour.

Compared with the prior art, the invention has the beneficial effects that:

the invention realizes the continuous strengthening process of active defense, active strengthening and forced strengthening in the drilling process through the synergistic effect of the flexibilizer, the leak preventer and the reinforcing agent, has high compression resistance and high shear resistance, and effectively avoids the leakage condition in the deep drilling process.

Detailed Description

The present invention will be further described with reference to the following embodiments.

The raw materials in the examples, i.e., the comparative examples, were all commercially available;

the elastic graphite has a resilience rate of more than or equal to 40% under the conditions of 52MPa and 30min and a resilience rate of more than or equal to 60% under the conditions of 30MPa and 30 min;

the core-shell particles comprise polymethyl methacrylate as a shell and acrylated polyurethane as a core;

the fiber material consists of kapok fiber, silk fiber, flax fiber, coconut fiber and asbestos fiber;

calcium carbonate is calcium carbonate with different grain diameters of 100 meshes, 200 meshes, 400 meshes, 800 meshes, 1500 meshes and 2500 meshes according to the mass ratio of 1:1: 1:1: 0.8: 0.8 of a mixture;

the reinforcing agent is prepared by the following method:

performing injection molding on polyetherimide by using spherical, regular dodecahedral, regular octahedral and regular tetrahedral molds with different sizes to obtain plastic particles with spheroidal, regular tetrahedron, regular octahedral or regular dodecahedral forms;

when the die is regular tetrahedron, the length of the edge of the regular tetrahedron is less than or equal to 1500 mu m; when the mold is a regular octahedron, the length from any vertex of the regular octahedron to other vertices is less than or equal to 1500 μm; when the die is a regular dodecahedron, the length from any vertex of the regular dodecahedron to other vertices is less than or equal to 1500 μm.

Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.

Example 1

In a high-temperature high-pressure well 5010m, polymer drilling fluid is used for drilling, and the density of the drilling fluid is 1.52g/cm³Drilling and leakage repairing while drilling are carried out according to the following method:

adding 2 parts by weight of a flexibilizer (the specific composition of the flexibilizer is a mixture of emulsified asphalt, polyvinyl acetate and paraffin according to a mass ratio of 1:1: 1) into 100 parts of the polymer drilling fluid, and drilling a well for 110 m;

adding 4 parts by weight of a leakage preventer (the leakage preventer specifically comprises a mixture of elastic graphite, a fiber material, oil-soluble polystyrene, activated carbon, calcium carbonate, silane coupling agent modified quartz sand, core-shell particles and walnut shell particles in a mass ratio of 0.3:1.5:1:0.5:2:1:1: 0.5), and continuously drilling without leakage loss;

2 parts by weight of a first particle size enhancer (polyetherimide, having an average particle size of 860 μm and a morphology of spheroidal, regular tetrahedral and regular dodecahedral) was added, and drilling was continued without loss.

Example 2

In a certain high-temperature high-pressure well 5823m, polymer drilling fluid is used for drilling, and the density of the drilling fluid is 1.62g/cm³Drilling and leakage repairing while drilling are carried out according to the following method:

adding 2 parts by weight of a flexibilizer (the specific composition of the flexibilizer is a mixture of emulsified asphalt, rigid polyvinyl chloride and paraffin according to a mass ratio of 1:1: 1) into 100 parts of the polymer drilling fluid, and drilling a well for 65 m;

adding 5 parts by weight of a leak preventer (the leak preventer specifically comprises elastic graphite, fiber materials, acrylic resin, metal fiber felt, calcium carbonate, quartz sand modified by a silane coupling agent, core-shell particles and cottonseed hull particles according to a mass ratio of 0.3:1.5:1:0.5:2:1:1: 0.5), continuously drilling, and allowing 2.3m of the mixture to appear³Loss of Per hourThe conditions are as follows;

3 parts by weight of a first particle size enhancer (mean particle size 860 μm in the form of spheroidal, regular tetrahedral and regular dodecahedral), 2 parts by weight of a second particle size enhancer (mean particle size 1110 μm in the form of spheroidal, regular octahedral and regular dodecahedral), 1 part by weight of a third particle size enhancer (mean particle size 1350 μm in the form of spheroidal, regular tetrahedral and regular octahedral) were added, and drilling was continued without loss.

Example 3

5925m of a certain high-temperature high-pressure well, oil-based drilling fluid is used for drilling, the oil-water ratio is 85:15, the oil is 5# white oil, and the density of the drilling fluid is 1.64g/cm³Drilling and leakage repairing while drilling are carried out according to the following method:

adding 2 parts by weight of flexibilizer (the composition of the flexibilizer is the same as that in example 1) into 100 parts of oil-based drilling fluid, and drilling a well with the depth of 126 m;

5 parts by weight of a leakage preventing agent (the composition of the leakage preventing agent is the same as that in example 1) was added, drilling was continued, and 2.7m appeared³A loss case,/h;

adding 3 parts by weight of a first particle size enhancer (with an average particle size of 910 μm, the shape of a spheroid and a regular dodecahedron), adding 2 parts by weight of a second particle size enhancer (with an average particle size of 1120 μm, the shape of a spheroid, a regular dodecahedron and a regular octahedron), adding 1 part by weight of a third particle size enhancer (with an average particle size of 1380 μm, the shape of a spheroid, a regular dodecahedron, a regular octahedron and a regular tetrahedron), and continuously drilling without leakage.

Comparative example 1

In a certain high-temperature high-pressure well 6020m, polymer drilling fluid is used for drilling, and the density of the drilling fluid is 1.65g/cm³Drilling and leakage repairing while drilling are carried out according to the following method:

adding 3 parts by weight of 1000-mesh calcium carbonate particles (13-75 mu m) into 100 parts of polymer drilling fluid, and drilling for 23m to cause leakage at the leakage rate of 1.8m³/h；

Adding 3 parts by weight of 1000-mesh calcium carbonate particles (13-75 mu m) and 2 parts by weight of 200-mesh walnut shell particles (75-150 mu m), and drilling fluid loss occurs after drilling for 11m, wherein the loss rate is 3.9m³And h, the successful plugging effect cannot be achieved.

The drilling of the well was continued by adding 2 parts by weight of a flexibilizer (composition same as in example 1) and 4 parts by weight of a leakproof agent (composition same as in example 1) to 100 parts of the polymer drilling fluid, supplementing 4 parts by weight of a first particle size enhancer (composition same as in example 2), 2 parts by weight of a second particle size enhancer (composition same as in example 2) and 2 parts by weight of a third particle size enhancer (composition same as in example 2), and no loss occurred.

Comparative example 2

In a high-temperature high-pressure well 5763m, oil-based drilling fluid is used for drilling, the oil-water ratio is 80:20, the oil is 5# white oil, and the density of the drilling fluid is 1.59g/cm³Drilling and leakage repairing while drilling are carried out according to the following method:

adding 4 parts by weight of 1000-mesh calcium carbonate particles (13-75 mu m) into 100 parts of polymer drilling fluid, and allowing the drilling fluid to leak for 46m at a leakage rate of 3.2m³/h；

Adding 4 parts by weight of 1000-mesh calcium carbonate particles (13-75 mu m) and 2 parts by weight of 200-mesh walnut shell particles (75-150 mu m), drilling fluid loss occurs after the drilling is carried out for 9m, and the loss rate is 3.1m³The successful plugging effect can not be achieved;

the oil-based drilling fluid is continuously drilled with the addition of 100 parts by weight of the flexibilizer (the composition is the same as that in example 2), 4 parts by weight of the leakproof agent (the composition is the same as that in example 2), 3 parts by weight of the first particle size enhancer (the composition is the same as that in example 2), 2 parts by weight of the second particle size enhancer (the composition is the same as that in example 2) and 2 parts by weight of the third particle size enhancer (the composition is the same as that in example 2), and no loss occurs.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.