阅读说明：本技术 温敏型凝胶堵漏浆 (Temperature-sensitive gel plugging slurry ) 是由 王磊磊 张坤 苏君 尹丽 马红 霍宝玉 张健 孙双 郭剑梅 何鹏 于 2020-05-28 设计创作，主要内容包括：本发明公开了一种温敏型凝胶堵漏浆,包括5～10％的温敏凝胶堵漏剂、2～5％的刚性堵漏材料、1～2％纤维类堵漏材料和1～2％层状堵漏材料,以上各组分的含量以水的质量计；其中,温敏凝胶堵漏剂由以质量分数计的40～50％的可得然胶、40～50％的钻井液用膨润土、1～2％纯碱和5～15％提粘剂混合而成；该温敏型凝胶堵漏浆在高温下成凝胶状态,在漏层中粘滞阻力更大,承压能力更强；且其与常规堵漏浆相比,本申请的温敏型凝胶堵漏浆的凝胶状态形成仅与温度相关,不受其它堵漏材料影响其成胶效果,且纤维类等堵漏材料的存在还能够使胶体结构力更强。(The invention discloses temperature-sensitive gel plugging slurry, which comprises 5-10% of a temperature-sensitive gel plugging agent, 2-5% of a rigid plugging material, 1-2% of a fiber plugging material and 1-2% of a layered plugging material, wherein the contents of the components are calculated by the mass of water; wherein the temperature-sensitive gel plugging agent is prepared by mixing 40-50% of curdlan, 40-50% of bentonite for drilling fluid, 1-2% of soda ash and 5-15% of adhesion promoter in percentage by mass; the temperature-sensitive gel leakage-blocking slurry is in a gel state at high temperature, and has larger viscous resistance and stronger bearing capacity in a leakage layer; compared with the conventional leakage stoppage slurry, the gel state formation of the temperature-sensitive gel leakage stoppage slurry is only related to the temperature, the gelling effect of the temperature-sensitive gel leakage stoppage slurry is not influenced by other leakage stoppage materials, and the existence of the fiber leakage stoppage materials and the like can also enable the colloid structure force to be stronger.)

1. The temperature-sensitive gel leakage blocking slurry is characterized by comprising 5-10% of a temperature-sensitive gel leakage blocking agent, 2-5% of a rigid leakage blocking material, 1-2% of a fiber leakage blocking material and 1-2% of a layered leakage blocking material, wherein the contents of the components are calculated by the mass of water; the temperature-sensitive gel plugging agent is prepared by mixing 40-50% of curdlan, 40-50% of bentonite for drilling fluid, 1-2% of soda ash and 5-15% of a viscosity enhancer in percentage by mass, and the sum of the percentage by mass of the components is 100%.

2. The temperature-sensitive gel leakage blocking paste according to claim 1, wherein the viscosity enhancer is at least one of carboxymethyl starch and polyanionic cellulose.

3. The temperature-sensitive gel leakage-stopping slurry according to claim 1, wherein the rigid leakage-stopping material is at least one of nut shell, calcite and limestone, and the particle size of the rigid leakage-stopping material is 0.3-4 mm.

4. The temperature-sensitive gel leakage blocking paste according to claim 3, wherein the shell is at least one of walnut shell and apricot shell.

5. The temperature-sensitive gel leakage-stopping slurry according to claim 1, wherein the fiber leakage-stopping material is at least one of polypropylene fiber and bagasse, and the particle size of the fiber leakage-stopping material is 2 mm-10 mm.

6. The temperature-sensitive gel leakage-stopping slurry according to claim 1, wherein the layered leakage-stopping material is at least one of mica sheets and shell sheets, and the particle size of the layered leakage-stopping material is 0.15 mm-4 mm.

Technical Field

The invention relates to the technical field of petroleum and natural gas, in particular to temperature-sensitive gel leakage-stopping slurry.

Background

The well leakage is a worldwide problem, accounts for about 60% of the complexity of the current drilling accidents, particularly the vicious leakage of fractured strata not only loses the drilling time, but also easily causes engineering accidents such as well collapse, drill sticking and the like, and can cause out-of-control well blowout. The existing crosslinking type plugging gel mainly comprises crosslinking gels such as polyacrylamide, vegetable gum, polyvinyl alcohol and the like, but the existing crosslinking type gels need to be added with a crosslinking agent, so that the risk of short crosslinking time and uncontrollable time of partial gels exists.

As a novel plugging technology, gel plugging is insufficient in strength at high temperature and poor in pressure bearing capacity, is easy to polymerize in advance in the conveying process to influence plugging construction, cannot be matched with a conventional plugging agent for use, and is greatly limited to be applied on site. The curdlan is used as a natural polysaccharide plant, has a thermal gelation property, does not need to be added with a cross-linking agent, effectively avoids the risk of sudden aggregation, but the single curdlan cannot form solid gel in a high-temperature state, and the curdlan is not dissolved in cold water, so that the solution has no viscosity effect, cannot bear various weighting materials, and cannot realize the purpose of pressure-bearing and leakage-stopping of the stratum.

Disclosure of Invention

The invention aims to provide temperature-sensitive gel leakage-stopping slurry with high colloid strength and leakage-stopping effect.

Therefore, the technical scheme of the invention is as follows:

a temperature-sensitive gel leakage blocking slurry comprises 5-10% of a temperature-sensitive gel leakage blocking agent, 2-5% of a rigid leakage blocking material, 1-2% of a fiber leakage blocking material and 1-2% of a layered leakage blocking material, wherein the contents of the components are calculated by the mass of water; the temperature-sensitive gel plugging agent is prepared by mixing 40-50% of curdlan, 40-50% of bentonite for drilling fluid, 1-2% of soda ash and 5-15% of a viscosity enhancer in percentage by mass, and the sum of the percentage by mass of the components is 100%.

In the temperature-sensitive gel leakage-stopping slurry, the main components of the temperature-sensitive gel leakage-stopping agent are curdlan and bentonite for drilling fluid, wherein the curdlan has a structure similar to that of glucose, the surface of the curdlan is provided with a plurality of exposed hydroxyl groups, the main component of the bentonite for drilling fluid is montmorillonite which is aluminosilicate, the surface of the montmorillonite is provided with a plurality of exposed aluminum and has good water absorption, when the temperature-sensitive gel leakage-stopping agent is used for leakage-stopping operation, the curdlan and the bentonite for drilling fluid are added into water, and the exposed hydroxyl groups on the surface of the curdlan and the vacant potential phases of the exposed aluminum on the surface of the bentonite for drilling fluid interact to form hydrogen bonds under a certain temperature condition, so that solid gel can be formed under a high-temperature condition, free water is completely fixed, and the purpose of bearing and leakage stopping is achieved; meanwhile, the strength of the temperature-sensitive gel plugging agent is further increased by adding a certain proportion of soda, carboxymethyl starch and/or polyanionic cellulose; on the basis of the temperature-sensitive gel plugging agent, the rigid plugging material, the fiber plugging material and the layered plugging material are further added, so that the plugging slurry has high colloid strength and excellent plugging effect compared with the conventional plugging slurry.

Preferably, the viscosity enhancer is at least one of carboxymethyl starch and polyanionic cellulose.

Preferably, the rigid plugging material is at least one of fruit shell, calcite and limestone, and the particle size of the rigid plugging material is 0.3-4 mm.

Preferably, the shell is at least one of walnut shell and apricot shell.

Preferably, the fiber plugging material is at least one of polypropylene fiber and bagasse, and the particle size of the fiber plugging material is 2-10 mm.

Preferably, the layered plugging material is at least one of mica sheets and shell sheets, and the particle size of the layered plugging material is 0.15-4 mm.

The preparation method of the temperature-sensitive gel leakage-stopping slurry is simple and comprises the following steps: adding the components forming the temperature-sensitive gel plugging agent into water according to a certain proportion, stirring at a high speed for 20min, standing and maintaining for 4h at room temperature; then adding a rigid plugging material, a fiber plugging material and a layered plugging material into the mixture in proportion, and continuously stirring the mixture at a high speed for 20min to obtain a temperature-sensitive gel plugging slurry finished product.

Compared with the prior art, the temperature-sensitive gel leakage-blocking slurry has the following beneficial effects:

1) compared with the conventional leakage blocking slurry, the temperature-sensitive gel leakage blocking slurry disclosed by the application is in a gel state at high temperature, and has larger viscous resistance and stronger bearing capacity in a leakage layer;

2) compared with the conventional leakage stopping slurry, the gel state formation of the temperature-sensitive gel leakage stopping slurry is only related to the temperature, the gelling effect of the temperature-sensitive gel leakage stopping slurry is not influenced by other leakage stopping materials, and the existence of the leakage stopping materials such as fibers can also make the colloid structure stronger.

Drawings

FIG. 1 is a schematic diagram of temperature-sensitive gel plugging slurry of example 1 forming a solid gel after being heated to 80 ℃ in test one;

FIG. 2 is a schematic diagram of temperature-sensitive gel plugging slurry of example 2 forming solid gel after being heated to 80 ℃ in test one;

FIG. 3 is a schematic diagram of temperature-sensitive gel plugging slurry of example 3 forming solid gel after being heated to 80 ℃ in test one;

FIG. 4 is a schematic diagram of temperature-sensitive gel leakage blocking paste of comparative example 1, which forms a solid gel after being heated to 80 ℃ in test one.

Detailed Description

The invention will be further described with reference to the following figures and specific examples, which are not intended to limit the invention in any way. In the following examples and comparative examples, each component was purchased from a commercially available product.