CN104560003A - Organic boron zirconium crosslinking agent - Google Patents

Abstract

The invention provides an organoboron-zirconium crosslinking agent, which belongs to the technical field of oil field fracturing fluid. In order to solve the problems that the existing organoboron-zirconium crosslinking agent is prepared by using expensive organozirconium complexes as raw materials, which increases the raw material cost of the organoboron-zirconium crosslinking agent and reduces its economic benefits, the present invention provides a Organic boron zirconium crosslinking agent, its formula is (by weight): 1 part of inorganic zirconium salt; 2-4 parts of water; 3-6 parts of isopropanol; 0.4-1 part of inorganic boron compound; 4-20 parts of methanol ; 2-4 parts of polyol; 1-2 parts of sodium α-hydroxycarboxylate; 1-2 parts of triethanolamine; 0.5-1 part of tetrahydroxypropyl ethylenediamine. The organoboron-zirconium crosslinking agent provided by the invention uses cheap inorganic zirconium salts as raw materials, greatly saving costs, and is conducive to the marketization of the organoboron-zirconium crosslinking agent and its wide application in high-temperature resistant fracturing fluid systems.

Description

A kind of organic boron zirconium crosslinking agent

technical field

The invention relates to oilfield fracturing fluid technology, in particular to an organoboron-zirconium crosslinking agent used in a high-temperature resistant fracturing fluid system.

Background technique

Oilfield fracturing technology is a major measure for oil and gas well stimulation, and it is widely used in various oilfields. It uses ground high-pressure pumps to pump fracturing fluid into the formation with a displacement that greatly exceeds the absorption capacity of the formation, forming cracks in the formation, improving the conductivity of oil and gas layers, and achieving the purpose of increasing production.

Fracturing fluids have undergone tremendous evolution since they were first used to stimulate fractures in 1947. The early fracturing fluid was to add viscous fluid enough to open and extend fractures to gasoline; later, with the increase of well depth and well temperature, higher requirements were put forward for the viscosity of fracturing fluid, and the use of Guar gum and its derivatives based fracturing fluid.

High temperature resistant fracturing fluid system is a key technology for fracturing high temperature and low permeability reservoirs. In a high-temperature environment, the two main factors affecting the stability of the fracturing fluid jelly network structure are the stability of the polymer main chain and the stability of the cross-linking functional group, thus affecting its temperature resistance in the high-temperature fracturing fluid system The main components are thickeners and crosslinking agents.

For high temperature resistant fracturing fluid systems, the modified guar gum crosslinking system has been studied more, mainly including: organometallic crosslinking system, organoboron crosslinking system and organoboron zirconium crosslinking system. Organometallic (titanium, zirconium) cross-linked fracturing fluid systems have the advantages of high temperature resistance and delayed cross-linking. However, the jelly formed by this type of cross-linking agent is severely degraded mechanically under high-speed shearing, and has poor proppant-carrying ability. Moreover, the jelly formed by it does not have the ability to completely break the gel and degrade in a short time, resulting in serious damage to the conductivity of the support crack; the organoboron crosslinking agent has the advantages of good solubility and delayed crosslinking characteristics, but its formation The temperature resistance of jelly has certain limitations; organoboron zirconium crosslinking agent combines the advantages of organometallic crosslinking agent and organoboron crosslinking agent, which can effectively improve the temperature resistance and shear resistance of the fracturing fluid system High efficiency, less dosage, and also has delayed cross-linking effect.

The organoboron-zirconium crosslinking agent invented by U.S. Patent No. 5,217,632 is made from zirconium α-hydroxycarboxylates such as zirconium lactate, reacted with polyols for a period of time, and then reacted with inorganic boron and sodium hydroxide for a period of time. Organoboron-zirconium crosslinking agent OBZ-1 developed by Zhang Wensheng et al. in Shengli Oilfield (Zhang Wensheng, Qin Liping. Organoboron-zirconium crosslinking agent OBZ-1 for fracturing fluid[J]. Oilfield Chemistry, 1996, 13 (3): 210- 212.) and the organoboron-zirconium crosslinking agent BA1-21 developed by Xin Jun of Southwest Petroleum University (Guo Jianchun, Xin Jun, Wang Shibin, et al. Development and application of abnormal high temperature guar gum fracturing fluid system[J]. Petroleum Drilling Technology, 2010, 32 (3): 64-67.) is to introduce organic zirconium complexes into organic boron under strictly controlled reaction conditions to obtain organic boron zirconium crosslinking agent, and the organic boron colloidal particles are fixed by zirconium ions bond together to form larger colloidal particles, thus increasing the cross-link density and cross-link strength. Zhongyuan Oilfield Wang Dong et al. prepared a high-temperature delayed organic boron-zirconium crosslinking agent CZB-03 (Wang Dong, Wang Junying, Liu Hongsheng, et al. Preparation of high-temperature delayed organic boron-zirconium crosslinking agent CZB-03 for water-based fracturing fluid[J ]. Oilfield Chemistry, 2004, 21 (2): 113-115.), the crosslinking agent is composed of organic boron and organic zirconium crosslinking agent, and the temperature resistance of the formed fracturing fluid system is higher than 160 °C. The organic boron-zirconium crosslinking agent invented by US Patent US7683011 suitable for reservoirs at 135~163°C reacts with alkanolamines and zirconium complexes, then reacts with water and hydroxyalkylene diamines, and finally reacts with boron compounds be made of.

It can be seen from the above published literature that many organoboron-zirconium crosslinking agents are currently prepared from organozirconium complexes. However, due to the high price of organozirconium complexes, the cost of raw materials for organoboron-zirconium crosslinking agents is high, which further reduces the economic benefits of oil field fracturing.

In addition, in order to improve the temperature and shear resistance of organoboron-zirconium crosslinking agents in high-temperature fracturing fluid systems, some organoboron-zirconium crosslinking The market production of the agent brings certain difficulties; the preparation of some organoboron-zirconium crosslinking agents needs to be divided into multiple steps (for example, the organoboron crosslinking agent and the organozirconium crosslinking agent are synthesized separately and then compounded Obtain organic boron zirconium crosslinking agent), and there is also a separation process of intermediates, the operation procedure is cumbersome, time-consuming, and the production efficiency is low.

Contents of the invention

In order to solve the above problems, the present invention provides an organoboron-zirconium crosslinking agent. The raw material is cheap and easy to obtain, and the preparation process is simple. It has good temperature resistance and shear resistance at high temperatures above 135°C.

The present invention adopts following technical scheme:

An organoboron-zirconium crosslinking agent, characterized in that, the organoboron-zirconium crosslinking agent is made of the following formula:

Calculated in parts by weight:

1 part of inorganic zirconium salt; 2-4 parts of water; 3-6 parts of isopropanol; 0.4-1 part of inorganic boron compound; 4-20 parts of methanol; 2-4 parts of polyol; 1-2 parts of triethanolamine; 0.5-1 part of tetrahydroxypropyl ethylenediamine.

Preferably, the inorganic zirconium salt is one or a combination of zirconium oxychloride or zirconium tetrachloride.

Preferably, the inorganic boron compound is one or a combination of boric acid or borax.

Preferably, the polyhydric alcohol is one or a combination of glycerol or ethylene glycol.

Preferably, the sodium α-hydroxycarboxylate is one or a combination of sodium lactate or sodium gluconate.

Further, the formula of the organoboron zirconium crosslinking agent can also be:

Calculated in parts by weight:

1 part of zirconium oxychloride; 2 parts of water; 3 parts of isopropanol; 0.4 part of boric acid; 4 parts of methanol; 2 parts of glycerol; 1 part of sodium lactate; 1 part of triethanolamine;

Further, the formula of the organic boron zirconium crosslinking agent can also be:

Calculated in parts by weight:

1 part of zirconium oxychloride; 4 parts of water; 6 parts of isopropanol; 0.5 part of boric acid; 10 parts of methanol; 4 parts of ethylene glycol; 2 parts of sodium lactate; 2 parts of triethanolamine;

Further, the organoboron zirconium crosslinking agent is made by the following method:

Add inorganic zirconium salt and isopropanol to water, stir evenly, pass ammonia gas at 55-60°C and reflux for 0.5-1 hour; then add polyhydric alcohol, sodium α-hydroxycarboxylate and alkanolamine After continuing to react for 2-4 hours, adding boron solution prepared from inorganic boron compound and methanol, and continuing to react for 2-4 hours, the organoboron-zirconium crosslinking agent is obtained.

An application of the above-mentioned organoboron-zirconium crosslinking agent in a high temperature resistant fracturing fluid system.

The beneficial effects of the present invention are:

(1) Many traditional organic boron-zirconium crosslinking agents are prepared from expensive organic zirconium complexes as raw materials, and the cost is high; while the organic boron-zirconium crosslinking agent provided by the present invention uses cheap inorganic zirconium salts as The raw material greatly saves the cost, which is beneficial to the marketization of the organoboron zirconium crosslinking agent and the wide application in the high temperature resistant fracturing fluid system.

(2) The organic boron-zirconium crosslinking agent provided by the present invention has the characteristics of high crosslinking efficiency and low dosage, and the gel formed with hydroxypropyl guar gum has good temperature and shear resistance, which can effectively improve The temperature and shear resistance of the fracturing fluid system. In addition, the organoboron-zirconium crosslinking agent provided by the present invention also has the effect of delaying crosslinking, reducing the pumping friction of fracturing fluid; There is a secondary cross-linking phenomenon in the cut, which improves its ability to create fractures and carry proppant.

(3) The organic boron-zirconium crosslinking agent provided by the present invention has low-cost raw materials in its formulation and can be prepared by a one-pot method. That is: using the formula provided by the present invention, according to the time interval provided by the present invention, the reaction raw materials are added sequentially, and the reflux reaction is carried out at a relatively mild reaction temperature of 55-60°C, without the need to separate intermediates, to obtain organoboron-zirconium cross-linked joint agent. The price of reaction raw materials is low, and the market prospect is great; there is no intermediate separation step in the preparation process, and the preparation process is simple and easy to operate. Compared with the prior art, the organic boron-zirconium complex formed by the formula and preparation process provided by the present invention is applied to the high temperature resistant fracturing fluid system, and the formed jelly has good temperature resistance at high temperatures above 135°C Shear resistance.

(4) By using the formula provided by the present invention, the reaction temperature required for the preparation of the organoboron-zirconium crosslinking agent is low, the conditions are mild and easy to control. If the reaction temperature is too high, it will reduce the solubility of inorganic zirconium salts (especially zirconium oxychloride) in isopropanol, and accelerate the process of forming zirconium gel from inorganic zirconium salts. If the temperature exceeds 80°C, inorganic zirconium salts (especially Zirconium oxychloride) solution will rapidly transform into a gel-like precipitate under alkali catalysis, resulting in difficulties in subsequent reactions; if the reaction temperature is too low, the complexation of inorganic zirconium salts, inorganic boron compounds and organic ligands will not be sufficient, and the inorganic The proportion of chemical components is large, and the crosslinking effect of the product is poor.

Description of drawings

Fig. 1 is the viscosity change curve of the jelly formed by the cross-linking agent in Example 5 of the present invention at 140°C and 170s ^-1 ;

Fig. 2 is the viscosity change curve of the jelly formed by the cross-linking agent of Example 6 of the present invention at 135°C and 170s ^-1 .

Detailed ways

The present invention will be further described below in conjunction with the examples, but the protection scope of the present invention is not limited to the scope of the examples.

Example 1

A kind of organic boron zirconium crosslinking agent, its formula is:

Calculated in parts by weight:

1 part of zirconium oxychloride; 2 parts of water; 3 parts of isopropanol; 0.4 part of boric acid; 4 parts of methanol; 2 parts of glycerol; 1 part of sodium lactate; 1 part of triethanolamine;

This organic boron zirconium crosslinking agent is prepared by the following steps:

(1) Mix 10g of zirconium oxychloride with 20g of water and 30g of isopropanol to form a zirconium salt solution, add it to a flask, and feed ammonia gas into the solution at 55°C, and reflux for 0.5 hours;

(2) Add 20g of glycerol, 10g of sodium lactate, 10g of triethanolamine, and 5g of tetrahydroxypropylethylenediamine to the flask in sequence, and react for 3 hours;

(3) Add a boron solution composed of 4g of boric acid and 40g of methanol into the flask, and react for 3 hours to obtain a light yellow organic boron-zirconium crosslinking agent.

Example 2

A kind of organic boron zirconium crosslinking agent, its formula is:

Calculated in parts by weight:

1 part of zirconium oxychloride; 4 parts of water; 6 parts of isopropanol; 0.5 part of borax; 10 parts of methanol; 4 parts of ethylene glycol; 2 parts of sodium lactate; 2 parts of triethanolamine;

This organic boron zirconium crosslinking agent is prepared by the following steps:

(1) Mix 10g of zirconium oxychloride, 40g of water and 60g of isopropanol to form a zirconium salt solution, add it to a flask, and feed ammonia gas into the solution at 60°C, and reflux for 1 hour;

(2) Add 40g of ethylene glycol, 20g of sodium lactate, 20g of triethanolamine, and 5g of tetrahydroxypropylethylenediamine to the flask in sequence, and react for 2 hours;

(3) Add a boron solution composed of 5 g of borax and 100 g of methanol to the flask, and react for 2 hours to obtain a light yellow organic boron-zirconium crosslinking agent.

Example 3

A kind of organic boron zirconium crosslinking agent, its formula is:

Calculated in parts by weight:

1 part of zirconium tetrachloride; 2 parts of water; 4 parts of isopropanol; 0.8 parts of boric acid; 8 parts of methanol; 4 parts of glycerol; 1 part of sodium gluconate; 1 part of triethanolamine; share.

This organic boron zirconium crosslinking agent is prepared by the following steps:

(1) Mix 10g of zirconium tetrachloride, 20g of water and 40g of isopropanol to form a zirconium salt solution, add it to a flask, and feed ammonia gas into the solution at 58°C, and reflux for 1 hour;

(2) Add 40g of glycerol, 10g of sodium gluconate, 10g of triethanolamine, and 10g of tetrahydroxypropylethylenediamine to the flask in sequence, and react for 3 hours;

(3) Add a boron solution composed of 8g boric acid and 80g methanol to the flask, and react for 2 hours to obtain a light yellow organic boron-zirconium crosslinking agent.

Example 4

A kind of organic boron zirconium crosslinking agent, its formula is:

Calculated in parts by weight:

1 part of zirconium tetrachloride; 3 parts of water; 6 parts of isopropanol; 1 part of borax; 20 parts of methanol; 3 parts of ethylene glycol; 1.5 parts of sodium gluconate; 1.5 parts of triethanolamine; share.

This organic boron zirconium crosslinking agent is prepared by the following steps:

(1) Mix 10g of zirconium tetrachloride, 30g of water and 60g of isopropanol to form a zirconium oxychloride solution, add it to a flask, feed ammonia into the solution at 59°C, and reflux for 0.8 hours;

(2) Add 30g of ethylene glycol, 15g of sodium gluconate, 15g of triethanolamine, and 10g of tetrahydroxypropylethylenediamine to the flask in sequence, and react for 3 hours;

(3) Add a boron solution composed of 10g of borax and 200g of methanol into the flask, and react for 4 hours to obtain a light yellow organic boron-zirconium crosslinking agent.

Example 5

Configure the fracturing fluid base fluid in tap water according to the following formula ("%" in this example indicates the mass concentration): 0.55% thickener JK101 (namely: hydroxypropane produced in Kunshan Jingkun Oilfield Chemical Technology Development Company base guar gum), 1% clay stabilizer KCl, 0.5% drainage aid CF-5A (produced in Changqing Underground Oilfield Auxiliary Co., Ltd.), 0.05% fungicide formaldehyde, 0.04% pH regulator NaOH; in the formula After all materials were added and stirred well, it was left to stand for 4 hours. Add 0.5% of the organoboron zirconium crosslinking agent prepared in Example 1 to the prepared fracturing fluid base fluid, and form a jelly with good hanging properties within 8 minutes. The temperature resistance and shear resistance of the jelly at a temperature of 140 °C and a shear rate of 170 s ^-1 were measured by a Huck MARSⅢ rotational rheometer, and the viscosity change curve is shown in Figure 1.

It can be seen from Figure 1 that the jelly has secondary crosslinking phenomenon under high temperature shearing, and the viscosity of the jelly remains above 50 mPa·s after continuous shearing for 120 min. It shows that the organoboron-zirconium crosslinking agent obtained in Example 1 has high crosslinking efficiency and low dosage, and its ability to create fractures and carry proppants is high. The gel formed with hydroxypropyl guar gum can withstand high temperatures above 140° It still has good temperature and shear resistance, which can effectively improve the temperature and shear resistance of the fracturing fluid system.

Example 6

Configure the fracturing fluid base fluid according to the formula in Example 5, add 0.5% (mass concentration) of the organoboron zirconium crosslinking agent prepared in Example 2 to the configured fracturing fluid base fluid, and form hanging properties within 8 minutes Good jelly. The temperature resistance and shear resistance of the jelly at a temperature of 135 °C and a shear rate of 170 s ^-1 were measured by a Huck MARSⅢ rotational rheometer, and the viscosity change curve is shown in Figure 2.

The jelly has a secondary crosslinking phenomenon under high temperature shearing, and the viscosity of the jelly remains above 80 mPa·s after continuous shearing for 120 min. It shows that the organic boron-zirconium crosslinking agent obtained in Example 2 has high crosslinking efficiency, low dosage, high ability to create seams and carry proppant, and the gel formed with hydroxypropyl guar gum has good temperature resistance and shear resistance It can effectively improve the temperature and shear resistance of the fracturing fluid system.

Claims (9)

1. an organic boron zirconium cross linking agent, is characterized in that, described organic boron zirconium cross linking agent is made up of following formula:

Calculate by weight:

Inorganic zirconium salts 1 part; Water 2-4 part; Virahol 3-6 part; Inorganic compounds of boron 0.4-1 part; Methyl alcohol 4-20 part; Polyvalent alcohol 2-4 part; Alpha-hydroxy carboxylic acid compounds sodium 1-2 part; Trolamine 1-2 part; Tetrahydroxypropyl ethylenediamine 0.5-1 part.

2. a kind of organic boron zirconium cross linking agent according to claim 1, is characterized in that, described inorganic zirconium salts is the combination of a kind of in zirconium oxychloride or zirconium tetrachloride or two kinds.

3. a kind of organic boron zirconium cross linking agent according to claim 1, is characterized in that, described inorganic compounds of boron is the combination of a kind of in boric acid or borax or two kinds.

4. a kind of organic boron zirconium cross linking agent according to claim 1, is characterized in that, described polyvalent alcohol is the combination of a kind of in glycerol or ethylene glycol or two kinds.

5. a kind of organic boron zirconium cross linking agent according to claim 1, is characterized in that, described alpha-hydroxy carboxylic acid compounds sodium is the combination of a kind of in Sodium.alpha.-hydroxypropionate or Sunmorl N 60S or two kinds.

6. a kind of organic boron zirconium cross linking agent according to claim 1-5, is characterized in that, the formula of described organic boron zirconium cross linking agent also can be:

Calculate by weight:

Zirconium oxychloride 1 part; 2 parts, water; Virahol 3 parts; Boric acid 0.4 part; Methyl alcohol 4 parts; Glycerol 2 parts; Sodium.alpha.-hydroxypropionate 1 part; Trolamine 1 part; Tetrahydroxypropyl ethylenediamine 0.5 part.

7. a kind of organic boron zirconium cross linking agent according to claim 1-5, is characterized in that, the formula of described organic boron zirconium cross linking agent also can be:

Calculate by weight:

Zirconium oxychloride 1 part; 4 parts, water; Virahol 6 parts; Boric acid 0.5 part; Methyl alcohol 10 parts; Ethylene glycol 4 parts; Sodium.alpha.-hydroxypropionate 2 parts; Trolamine 2 parts; Tetrahydroxypropyl ethylenediamine 0.5 part.

8. a kind of organic boron zirconium cross linking agent according to claim 1, is characterized in that, described organic boron zirconium cross linking agent is made by the following method:

In water, add inorganic zirconium salts and Virahol, after stirring, at 55-60 DEG C, pass into ammonia and back flow reaction 0.5-1 hour; And then add polyvalent alcohol, alpha-hydroxy carboxylic acid compounds sodium and alkanolamine, continue reaction after 2-4 hour, then add the B solution prepared by inorganic compounds of boron and methyl alcohol, continue reaction after 2-4 hour, obtain described organic boron zirconium cross linking agent.

9. the application of organic boron zirconium cross linking agent in high temperature resistance fracturing fluid system described in an any one of claim 1-8.