CN-122012042-A - Environment-friendly nano shale inhibitor, preparation method thereof and water-based drilling fluid

CN122012042ACN 122012042 ACN122012042 ACN 122012042ACN-122012042-A

Abstract

The application discloses an environment-friendly nano shale inhibitor, a preparation method thereof and water-based drilling fluid, wherein the preparation method comprises the steps of preparing or obtaining amino acid salt, enabling amino acid salt molecules to be subjected to ion combination and partial amidation reaction with oxygen functional groups on the surface of nano active carbon, and enabling partial amino acid salt molecules to enter a nano active carbon pore canal to obtain the shale inhibitor; the shale inhibitor disclosed by the application can effectively reduce the hydration, dispersion and spalling degree of shale, remarkably improve the stability of a well wall, effectively avoid the negative influence on the performance of the water-based drilling fluid, is environment-friendly, has a certain shale well wall blocking effect, and completes the multi-element functional promotion of the water-based drilling fluid, thereby guaranteeing the safety and efficiency of the drilling operation of the water-based drilling fluid, and simultaneously reducing the drilling cost and protecting the environment.

Inventors

ZHANG KUN
PAN YONGQIANG
XU YUNLONG
YANG XIUTIAN
WANG JUNJIE
ZHU XUEYOU
ZHANG YUWEN
LI HAODONG
ZHU XIUYU

Assignees

大庆钻探工程有限公司
中国石油天然气集团有限公司

Dates

Publication Date: 20260512
Application Date: 20251011

Claims (10)

1. The preparation method of the environment-friendly nano shale inhibitor is characterized by comprising the following steps: and (3) preparing or obtaining amino acid salt, carrying out ion combination and partial amidation reaction on the amino acid salt molecules and oxygen functional groups on the surface of the nano activated carbon, and enabling partial amino acid salt molecules to enter the pore canal of the nano activated carbon to obtain the shale inhibitor.
2. The method for preparing an environmentally friendly nano shale inhibitor according to claim 1, wherein the method for preparing amino acid salt comprises the following steps: the amino acid and potassium hydroxide are reacted for 50-70 min according to the mass ratio of 8-10:1 under the stirring state of 60-80 ℃ and the speed of 180-220 r/min, and the reaction product is the amino acid salt.
3. The method for preparing the environment-friendly nano shale inhibitor according to claim 1 or 2, which is characterized in that: The amino acid salt is glycinate, glutamate or lysinate.
4. The method for preparing the environment-friendly nano shale inhibitor according to claim 3, wherein the method for making the amino acid salt molecules and the oxygen functional groups on the surface of the nano activated carbon undergo the ion combination and partial amidation reaction and making partial amino acid salt molecules enter the pore canal of the nano activated carbon comprises the following steps: And (3) reacting a mixed system consisting of amino acid salt, nano activated carbon and alcohol dispersing agent at 180-220 ℃ to obtain a reaction product, namely the shale inhibitor.
5. The method for preparing the environment-friendly nano shale inhibitor, which is characterized in that: the mass ratio of the amino acid salt to the nano activated carbon is 5-7:1, and the mass ratio of the amino acid salt to the alcohol dispersing agent is 1:5.
6. The method for preparing the environment-friendly nano shale inhibitor, which is characterized in that: When a mixed system formed by amino acid salt, nano activated carbon and alcohol dispersing agent reacts at 180-220 ℃, the mixed system is stirred at the same time, the stirring speed is 350-450 r/min, and the reaction time is 22-26 h.
7. The method for preparing the environment-friendly nano shale inhibitor according to claim 3, which is characterized in that: The nanometer activated carbon is sugarcane-based or corncob-based nanometer activated carbon.
8. The method for preparing the environment-friendly nano shale inhibitor according to claim 3, which is characterized in that: the alcohol dispersant is methanol, ethanol or isopropanol.
9. An environment-friendly nano shale inhibitor, which is characterized in that: the shale inhibitor is produced using the method of any one of claims 1-8.
10. A water-based drilling fluid, comprising: comprising the environmentally friendly nano shale inhibitor of claim 9.

Description

Environment-friendly nano shale inhibitor, preparation method thereof and water-based drilling fluid Technical Field The invention relates to the technical field of drilling fluid in petroleum drilling, in particular to an environment-friendly nano shale inhibitor, a preparation method thereof and water-based drilling fluid. Background In shale oil drilling, especially in long horizontal section drilling, well wall instability frequently occurs, and safe and efficient drilling is seriously affected. Oil-based drilling fluids are often used to drill wells to maintain borehole wall stability, rather than water-based drilling fluids. However, the oil-based drilling fluid has high cost and serious environmental pollution, does not meet the requirements of cost reduction and synergy of oil fields and increasingly severe environmental protection, so the future technology is developed into a water-based drilling fluid capable of replacing the oil-based drilling fluid. Shale inhibitors are added into the water-based drilling fluid, so that the hydration, dispersion and spalling degree of shale can be greatly reduced, and the method is an effective method for improving the stability of the well wall. Currently, shale inhibitors for water-based drilling fluids are developed in a wide variety, but are mostly polyamines and derivatives thereof, polyquaternium and derivatives thereof, potassium chloride and other organic potassium salts. The inhibitor has the main defects that the inhibition effect depends on high dosage, the inhibition capability is insufficient under low dosage, such as potassium salt and the like, the dosage is more than 5 percent, the hydration and pulping of clay in the drilling fluid are seriously inhibited while shale hydration is inhibited, rheological property is influenced, the fluid loss is increased, degradation products are difficult to degrade, the environment is harmful, the environmental friendliness of the drilling fluid is not improved, the multi-functional performance is not realized, and the comprehensive capability of stabilizing the shale well wall is poor. In addition, there are also synthetic polymer inhibitors at present, which have problems of difficult degradation and poor environmental protection performance. Aiming at the characteristic of subtle development of shale pore throats, the prior art also tries to realize physical blocking by adopting nano particles to enter pore throats so as to reduce permeability and filtrate invasion, but the prior nano blocking material has the defects of high cost, complex synthesis process and the like. Disclosure of Invention In view of the above, the present disclosure provides an environment-friendly nano shale inhibitor, a preparation method thereof and a water-based drilling fluid, which solve the problems that the existing shale inhibitor has negative influence on the performance of the water-based drilling fluid, has single function, has poor comprehensive ability of stabilizing shale well walls, is difficult to degrade, and the like. To solve the above technical problems, in a first aspect, the preparation method of the environment-friendly nano shale inhibitor disclosed in the present disclosure includes: And (3) obtaining amino acid salt and nano activated carbon, enabling the amino acid salt molecules and oxygen functional groups on the surface of the nano activated carbon to generate ion combination and partial amidation reaction, and enabling partial amino acid salt molecules to enter a pore channel of the nano activated carbon to obtain the shale inhibitor. Preferably, the method for obtaining an amino acid salt comprises the following steps: the amino acid and potassium hydroxide are reacted for 50-70 min according to the mass ratio of 8-10:1 under the stirring state of 60-80 ℃ and the speed of 180-220 r/min, and the reaction product is the amino acid salt. Preferably, the amino acid salt is a glycine salt, a glutamate salt or a lysine salt. Preferably, the method for making the amino acid salt molecules and the oxygen functional groups on the surface of the nano activated carbon undergo the ion combination and partial amidation reaction and making partial amino acid salt molecules enter the pore canal of the nano activated carbon comprises the following steps: And (3) reacting a mixed system consisting of amino acid salt, nano activated carbon and alcohol dispersing agent at 180-220 ℃ to obtain a reaction product, namely the shale inhibitor. Preferably, the mass ratio of the amino acid salt to the nano activated carbon is 5-7:1, and the mass ratio of the amino acid salt to the alcohol dispersing agent is 1:5. Preferably, when a mixed system consisting of amino acid salt, nano activated carbon and alcohol dispersing agent is reacted at 180-220 ℃, the mixed system is stirred at the same time, the stirring speed is 350-450 r/min, and the reaction time is 22-26 h. Preferably, the nano activated carbon is a sugarcane-based or cor