CN117263195A - Organic soil for high-temperature-resistant synthetic base drilling fluid and preparation method thereof - Google Patents

Abstract

The invention provides organic soil for high-temperature resistant synthetic base drilling fluid and a preparation method thereof, wherein the organic soil comprises the following raw materials in parts by weight: 50-75 parts of purified sodium bentonite methyl bentonite; 15-30 parts of 1-octadecene trimethyl ammonium chloride; 1-10 parts of intercalation auxiliary agent; 1000-1500 parts of water. The organic soil for the high-temperature resistant synthetic base drilling fluid has high temperature resistance, good tackifying and cutting effects, and can improve the adhesive cutting force and high-temperature stability of the synthetic base drilling fluid, thereby solving the problems of heavy spar sedimentation, poor rock carrying capacity and the like caused by low adhesive cutting force of the drilling fluid in the process of drilling deep wells and ultra-deep wells.

Description

A kind of high temperature resistant synthetic base drilling fluid organic soil and its preparation method

Technical field

The invention belongs to the technical field of petrochemical industry, relates to the technical field of organic soil for drilling fluids, and specifically relates to an organic bentonite for high-temperature resistant oil-based drilling fluids and a preparation method thereof.

Background technique

Bentonite is a hydrous clay mineral mainly composed of montmorillonite. Molecular formula: Na _x (H ₂ O) ₄ (Al _2-X Mg _0.83 )Si ₄ O ₁₀ )(OH) ₂ . Due to its special properties, such as : Swellability, adhesion, adsorption, catalysis, thixotropy, suspension and cation exchange properties are used in various fields. Our country is very rich in bentonite mineral resources, with the content ranking second in the world after the United States. However, its deep processing and utilization are far less than those abroad. It has been in the initial development and application stage. Only in recent years has research work on the deep processing and utilization of bentonite been carried out. Organic bentonite is One of the fine products of bentonite deep processing. Due to its hydrophobic and lipophilic properties, organic bentonite has good dispersion, solubility and emulsification in organic solvents. It is widely used in industrial fields such as oil drilling, paints, inks, high-temperature greases, cosmetics, castings, pesticides, etc. as anti-settling agents, thickeners, tackifiers and suspending agents.

Organobentonite is the most basic lipophilic colloid in oil-based drilling fluids. In oil-based drilling fluids, it can not only increase the viscosity and shear force of the mud, but also reduce the filter loss of oil-based drilling fluids. Therefore, organobentonite is an important component of oil-based drilling fluids. An indispensable additive in the liquid. Organic soil mainly plays the role of increasing viscosity and improving shear in drilling fluids, and its performance will directly affect the rheology and rock-carrying ability of drilling fluids. Organic bentonite can also enhance the stability of synthetic-based emulsions to a certain extent and act as a solid emulsifier. At present, the preparation method of organic soil on the market generally uses ion exchange adsorption of cationic surfactants and highly dispersed hydrophilic clay. This combination will decompose at high temperatures, and the organic soil has poor temperature resistance, so it is not resistant to The preparation of organic soil for high-temperature oil-based drilling fluids was studied.

Contents of the invention

The purpose of the present invention is to propose an organic soil for high-temperature resistant synthetic-based drilling fluid and a preparation method thereof.

The method of the invention can greatly improve the temperature resistance and rheological properties of organic bentonite for drilling fluid, and create an organic bentonite with excellent performance, with a temperature resistance of up to 200°C.

The main technical solution of the present invention: organic soil for high-temperature resistant synthetic base drilling fluid, which is characterized by including the following raw materials in parts by weight:

Purified sodium bentonite potassium bentonite mixture 50-75 parts

One time intercalation agent 15-30 parts

Intercalation additive 1-10 parts

Water 1000-1500 parts.

Generally, the primary intercalation agent is 1-octadecenetrimethylammonium chloride.

The intercalation aid is polyvinyl alcohol [C ₂ H ₄ O]n with a molecular weight of 300-5000. It is used to improve the adsorption stability of quaternary ammonium salts on clay and weaken the desorption effect of quaternary ammonium salts at high temperatures.

The method for preparing organic soil for high-temperature resistant synthetic base drilling fluid provided by the invention is characterized by: dispersing the purified sodium bentonite and potassium bentonite mixture in deionized water to obtain a stable suspension; a primary intercalation agent and an intercalation aid. The agent performs a primary intercalation reaction with the suspension under the action of the initiator to obtain the primary intercalation material; the primary intercalation material and the intercalation auxiliary undergo a secondary intercalation reaction to obtain the secondary intercalation material; the secondary intercalation material is dried , crushed and sieved to obtain organic soil for high temperature resistant synthetic base drilling fluid.

Preferably, the mixture of purified sodium bentonite and potassium bentonite is dispersed in deionized water, stirred at high speed to obtain a stable suspension, and the pH value of the suspension is adjusted to 7 to 8.

In the primary intercalation reaction, the organic soil material liquid is obtained by stirring and reacting at 60°C-80°C for 1-2 hours. The organic soil material liquid is filtered to remove moisture and the primary intercalation material is obtained.

The secondary intercalation reaction: the primary intercalation material and the intercalation auxiliary react for 30-120 minutes at a temperature of 60°C-80°C to obtain the secondary intercalation material, which is heated at 60°C-80°C Dry for 3-5 hours, cool to room temperature, crush and pass through a 200-mesh sieve to obtain organic soil for high-temperature resistant synthetic base drilling fluid.

The initiator is one or more of ceric ammonium nitrate, potassium persulfate, and ammonium persulfate.

The equipment used for the mixing and stirring operations in the primary intercalation reaction is a reaction kettle with a heating, stirring, and cooling system, and the equipment used for the filter press is a plate and frame filter press.

Both the primary intercalation reaction and the secondary intercalation reaction adopt wet heating.

The organic soil for high-temperature resistant synthetic base drilling fluid provided by the invention uses 1-octadecyltrimethylammonium chloride as a primary intercalation agent, and adds an intercalation aid. Under the action of the initiator, it The base soil mixture is intercalated once, and one of the C=C double bonds in the 1-octadecyltrimethylammonium chloride and intercalation aid is broken and combined with the Al atom in the partially purified sodium potassium base soil mixture. Generate strong σ bonds, eventually forming chemical bonds and ionic bond copolymer organic soil products.

The outstanding effects of the present invention are:

The organic soil for high-temperature resistant synthetic-based drilling fluid obtained by the present invention is resistant to high temperatures and has good viscosity-increasing and shear-increasing effects. It can improve the viscosity-shear force and high-temperature stability performance of the synthetic-based drilling fluid, thereby solving problems in the process of drilling deep wells and ultra-deep wells. Problems such as barite settlement and poor rock-carrying ability are caused by the low viscous shear force of the drilling fluid.

In the intercalation reaction quaternary ammonium salt and intercalation aid of the present invention, one of the C=C double bonds in the intercalation reaction quaternary ammonium salt and the intercalation aid is broken under certain conditions, resulting in two σ bonds, which are formed by intercalation reaction with the purified sodium-based and potassium-based soil mixture. Chemical bond and ionic bond copolymer, under certain conditions, add layered structure intercalation additives twice to form dispersed small crystal plate-like distribution of organic soil, which has good high temperature resistance and thus produces lipophilic organic bentonite, ensuring that it can be used at high temperatures. Can be well dispersed in oil-based drilling fluids.

Detailed ways

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

In the following examples, the intercalation aid is polyvinyl alcohol [C ₂ H ₄ O]n with a molecular weight of 300-5000; the initiator is one or more of ceric ammonium nitrate, potassium persulfate, and ammonium persulfate. .

Example The equipment used for the mixing and stirring operations in the primary intercalation reaction is a reaction kettle with a heating, stirring, and cooling system, and the equipment used for the filter press is a plate and frame filter press. Both the primary intercalation reaction and the secondary intercalation reaction adopt wet heating.

Example 1

Disperse 50 parts of sodium bentonite and potassium bentonite mixture into 700 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 20 parts of 1-octadecene Dissolve methylammonium chloride in 300 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 3 parts of intercalation aid in 200 parts of deionized water, stir evenly, and make it a clear and transparent solution b for later use. Under high-speed stirring, quickly add the initiator, solution a and solution b to the suspension, react at 75°C for 1.5 hours, continue to add 5 parts of intercalation aid, and stir for 1 hour. The product is cooled to room temperature, and the remaining Cl- in the product is repeatedly removed with deionized water, filtered, and the prepared organic bentonite is vacuum dried at 70°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

Example 2

Disperse 60 parts of sodium bentonite and potassium bentonite mixture into 800 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 22 parts of 1-octadecene Dissolve methylammonium chloride in 200 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 4 parts of the intercalation aid in 100 parts of deionized water and stir evenly to make a clear and transparent solution b for later use. Under high-speed stirring, quickly add the initiator, solution a and solution b to the suspension, react at 70°C for 1.5 hours, continue to add 5 parts of intercalation aids, and stir for 1 hour. The product is cooled to room temperature, and the remaining Cl- in the product is repeatedly removed with deionized water, filtered, and the prepared organic bentonite is vacuum dried at 75°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

Example 3

Disperse 65 parts of sodium bentonite and potassium bentonite mixture into 800 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 24.8 parts of 1-octadecene Dissolve methylammonium chloride in 200 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 2 parts of the intercalation aid in 100 parts of deionized water and stir evenly to make a clear and transparent solution b for later use. Under high-speed stirring, quickly add the initiator, solution a and solution b to the suspension, react at 70°C for 1.5 hours, continue to add 6 parts of intercalation aids, and react for 1 hour. The product is cooled to room temperature, and the remaining Cl- in the product is repeatedly removed with deionized water, filtered, and the prepared organic bentonite is vacuum dried at 70°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

Example 4

Disperse 70 parts of sodium bentonite and potassium bentonite mixture into 1500 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 26 parts of 1-octadecene Dissolve methylammonium chloride in 200 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 5 parts of intercalation aid in 100 parts of deionized water, stir evenly, heat to 80°C, and react for 10 minutes to make a clear and transparent solution b for later use. Under high-speed stirring, quickly add the initiator, solution a and solution b to the suspension, react at 70°C for 1.5 hours, continue to add 5 parts of the prepared intercalation aid, and stir for 1 hour. The product is cooled to room temperature, washed repeatedly with deionized water, and filtered. The prepared organic bentonite is vacuum dried at 75°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

Example 5

Disperse 85 parts of sodium bentonite and potassium bentonite mixture into 800 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 28 parts of 1-octadecene Dissolve methylammonium chloride in 200 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 3 parts of the intercalation aid in 100 parts of deionized water, stir evenly, heat to 80°C, and react for 10 minutes to make a clear and transparent solution b for later use. Under high-speed stirring, quickly add the initiator, solution a and solution b to the suspension, react at 70°C for 1.5 hours, continue to add 7 parts of the prepared intercalation aid, and stir for 1 hour. The product is cooled to room temperature, washed repeatedly with deionized water, and filtered. The prepared organic bentonite is vacuum dried at 75°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

Example 6

Disperse 65 parts of sodium bentonite and potassium bentonite mixture into 800 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 25 parts of 1-octadecene Dissolve methylammonium chloride in 200 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 2 parts of the intercalation aid in 100 parts of deionized water, stir evenly, heat to 80°C, and react for 10 minutes to make a clear and transparent solution b for later use. Under high-speed stirring, quickly add the initiator, solution a and solution b to the suspension, react at 70°C for 2 hours, continue to add 7 parts of the prepared intercalation aid, and stir for 0.5 hours. The product is cooled to room temperature, washed repeatedly with deionized water, and filtered. The prepared organic bentonite is vacuum dried at 75°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

Example 7

Disperse 70 parts of sodium bentonite and potassium bentonite mixture into 800 parts of deionized water, stir at high speed to obtain a stable suspension, adjust the pH value of the suspension to 7~8, and set aside; add 25 parts of 1-octadecene Dissolve methylammonium chloride in 200 parts of deionized water and stir evenly to make a clear and transparent solution a for later use. Dissolve 6 parts of the intercalation aid in 100 parts of deionized water, stir evenly, heat to 80°C, and react for 10 minutes to make a clear and transparent solution b for later use. Under high-speed stirring, quickly add solution a and solution b to the suspension, react at 70°C for 2 hours, continue to add 3 parts of the prepared intercalation aid, and stir for 0.5 hours. The product is cooled to room temperature, washed repeatedly with deionized water, and filtered. The prepared organic bentonite is vacuum dried at 75°C, pulverized, and passed through a 200-mesh sieve to obtain the organic bentonite product.

The samples prepared in the above examples were tested for performance and compared with similar products on the market:

Sample name Apparent viscosity (AV)/mpa·s Plastic viscosity (PV)/mpa·s Dynamic shear force (YP)/pa blank sample 3.8 3.6 0.2 Sample 1 15.0 9.0 6 Sample 2 14.0 9.0 5 Sample 3 14.0 8.0 6 Sample 4 11.5 7.0 4 Sample 5 19.5 12.0 7.5 Sample 6 16 12 4 Sample 7 18. 13 5 YH-918 (domestic) 10 8.5 1.5

It can be seen from the test results that the performance of the sample obtained by the method of the present invention is significantly better than that of the domestic market products.

The adhesive and shear properties of the high-temperature-resistant synthetic-based drilling fluid organocoil selected from sample 5 obtained in this example in the synthetic-based system were measured:

The emulsion formula is: synthetic base oil + 4% solid emulsifier + 3% organic soil + 5% fluid loss agent + 20% CaCl ₂ brine + barite

Through the temperature-resistant hot rolling test, after adding the organic soil of this embodiment to the synthetic-based drilling fluid, the obtained drilling fluid system has good rheological properties. After hot rolling at 200°C, the apparent viscosity and dynamic shear force Basically unchanged, the performance is stable, indicating that the organic soil prepared in this example has good thermal stability.

Claims (10)

1. The organic soil for the high-temperature resistant synthetic base drilling fluid is characterized by comprising the following raw materials in parts by weight:

50-75 parts of purified sodium bentonite and potassium bentonite mixture

15-30 parts of a primary intercalation agent

1-10 parts of intercalation auxiliary agent

1000-1500 parts of water.

2. The organic soil for high temperature resistant synthetic base drilling fluid according to claim 1, wherein: the primary intercalation agent is 1-octadecene trimethyl ammonium chloride.

3. The organic soil for high temperature resistant synthetic base drilling fluid according to claim 1, wherein: the intercalation aid is polyvinyl alcohol C ₂ H ₄ O]n, molecular weight 300-5000.

4. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid according to claim 1, wherein the method comprises the following steps: dispersing the purified sodium bentonite potassium bentonite mixture in deionized water to obtain a stable suspension; the primary intercalation agent and the intercalation auxiliary agent perform primary intercalation reaction with the suspension under the action of the initiator to obtain a primary intercalation material; performing secondary intercalation reaction on the primary intercalation material and the intercalation auxiliary agent to obtain a secondary intercalation material; and drying, crushing and sieving the secondary intercalation material to obtain the organic soil for the high-temperature resistant synthetic base drilling fluid.

5. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid, according to claim 4, wherein the method comprises the following steps: dispersing the purified sodium bentonite and potassium bentonite mixture in deionized water, stirring at a high speed to obtain a stable suspension, and adjusting the pH value of the suspension to 7-8.

6. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid, according to claim 4, wherein the method comprises the following steps: and (3) performing the primary intercalation reaction, stirring and reacting for 1-2 hours at the temperature of 60-80 ℃ to obtain an organic soil material liquid, and performing filter pressing on the organic soil material liquid to remove water to obtain the primary intercalation material.

7. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid, according to claim 4, wherein the method comprises the following steps: the secondary intercalation reaction: the first intercalation material and the intercalation auxiliary agent react for 30-120 minutes at the temperature of 60-80 ℃ to obtain a second intercalation material, the second intercalation material is dried for 3-5 hours at the temperature of 60-80 ℃, cooled to room temperature, crushed and sieved by a 200-mesh sieve to obtain the organic soil for the high-temperature resistant synthetic base drilling fluid.

8. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid, according to claim 4, wherein the method comprises the following steps: the initiator is one or more of ammonium cerium nitrate, potassium persulfate and ammonium persulfate.

9. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid according to claim 6, wherein the method comprises the following steps: the equipment used for mixing and stirring operation in the primary intercalation reaction is a reaction kettle with a heating, stirring and cooling system, and the equipment used for filter pressing is a plate-and-frame filter press.

10. The method for preparing the organic soil for the high-temperature resistant synthetic base drilling fluid according to claim 6 or 7, wherein the method comprises the following steps of: the first intercalation reaction and the second intercalation reaction are heated by wet method.