阅读说明：本技术 一种油田用硫酸钡阻垢剂及其制备方法 (Barium sulfate scale inhibitor for oil field and preparation method thereof ) 是由 邱哓翠 王逵 张保利 向礼勇 樊博强 刘磊 樊亮亮 郭强 周娟 于 2021-09-10 设计创作，主要内容包括：本发明公开了一种油田用硫酸钡阻垢剂及其制备方法,按质量百分比由以下组分组成：聚环氧琥珀酸34～69％、马来酸-丙烯酸共聚物8～30％,乙二胺四甲叉磷酸钠16～50％,以上各组份的重量百分比总和为100％。本发明解决现有硫酸钡阻垢剂阻垢效果不理想、且阻垢效果单一的问题。(The invention discloses a barium sulfate scale inhibitor for oil fields and a preparation method thereof, wherein the barium sulfate scale inhibitor comprises the following components in percentage by mass: 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the total weight percentage of the components is 100%. The invention solves the problems of non-ideal scale inhibition effect and single scale inhibition effect of the existing barium sulfate scale inhibitor.)

1. The barium sulfate scale inhibitor for the oil field is characterized by comprising the following components in percentage by mass: 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the total weight percentage of the components is 100%.

2. A preparation method of a barium sulfate scale inhibitor for oil fields is characterized by comprising the following steps:

step 1, weighing the following components in percentage by mass: 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, uniformly stirring the substances weighed in the step 1 to obtain the barium sulfate scale inhibitor.

3. The preparation method of the barium sulfate scale inhibitor for the oil field according to claim 2, wherein in the step 2, the stirring time is 10-20 min.

Technical Field

The invention belongs to the technical field of fine chemical engineering of oil fields, relates to a barium sulfate scale inhibitor for oil fields, and further relates to a preparation method of the barium sulfate scale inhibitor for oil fields.

Background

In the oil and gas field development process, scale formation is a difficult problem encountered in the secondary oil recovery process, injected water is mostly oil field produced water after treatment, chemical incompatibility possibly exists with formation water, when the injected water enters a reservoir, incompatible ions are easy to react to cause scale formation, in addition, conditions such as temperature, pressure, pH value and the like of the injected water are changed, the inter-phase balance of the reservoir is damaged, complex chemical reaction is caused between the water and the reservoir, and scale formation can also be caused. The scaling process can occur in various places such as reservoirs, pipelines, gathering and transportation equipment and the like, the deposition of scale can cause the local corrosion of the pipelines and the equipment, the pipeline and the equipment are perforated and damaged in a short period, the oil and gas production can be influenced when the scaling is serious, even the oil and gas well is stopped and scrapped, and the oil field is greatly lost.

The scale produced by oil and gas fields is mainly CaCO₃、CaSO₄、BaSO₄Scale, etc., wherein CaCO₃、CaSO₄The scale is easy to remove, and the scale formation problem can be effectively prevented by adding the scale inhibitor. BaSO₄Because the solubility product is very small, the formed barium sulfate scale is compact and hard in crystallization, strong in adhesive force, difficult to remove by a common method once formed and very harmful, and the best method is to add a scale inhibitor for prevention. At present, some special scale inhibitors for barium and strontium on the market resist BaSO₄The scale inhibition effect is not ideal, and the scale inhibition rate is about 70-85%. Therefore, the development of high-efficiency barium sulfate scale inhibitors is imminent.

Disclosure of Invention

The invention aims to provide a barium sulfate scale inhibitor for oil fields, which solves the problems of unsatisfactory scale inhibition effect and single scale inhibition effect of the existing barium sulfate scale inhibitor.

The invention also aims to provide a preparation method of the barium sulfate scale inhibitor for the oil field.

The technical scheme adopted by the invention is that the barium sulfate scale inhibitor for the oil field comprises 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the total weight percentage of the components is 100%.

The invention adopts another technical scheme that a preparation method of the barium sulfate scale inhibitor for the oil field is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, uniformly stirring the substances weighed in the step 1 to obtain the barium sulfate scale inhibitor.

The present invention is also characterized in that,

in the step 2, the stirring time is 10-20 min.

The barium sulfate scale inhibitor for the oil field has the beneficial effects of inhibiting BaSO₄、CaSO₄All have very excellent scale inhibition effect on single BaSO₄And CaSO alone₄The scale inhibition rate is over 90 percent; the preparation method is simple, easy to operate and easy to use.

Detailed Description

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

The invention provides a barium sulfate scale inhibitor for oil fields, which comprises the following components in percentage by mass: 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the total weight percentage of the components is 100%.

The invention also provides a preparation method of the barium sulfate scale inhibitor for the oil field, which is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 34-69% of polyepoxysuccinic acid, 8-30% of maleic acid-acrylic acid copolymer and 16-50% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, stirring the substances weighed in the step 1 for 10-20 min until the substances are uniformly mixed to obtain the barium sulfate scale inhibitor.

The polyepoxysuccinic acid (PESA) in the barium sulfate scale inhibitor for the oil field is a phosphorus-free and non-nitrogen green environment-friendly multi-component scale and corrosion inhibitor by Shandong Youso chemical technology Limited company, has good scale and dispersion performance on calcium carbonate, calcium sulfate and barium sulfate in water, has a certain corrosion inhibition effect, good biodegradation performance and wide application range;

the maleic acid-acrylic acid copolymer (MA/AA) is a low molecular weight polyelectrolyte prepared by polymerizing maleic acid and acrylic acid according to a certain proportion by Shandong Youso chemical technology Co., Ltd, has strong dispersion effect on carbonate and the like, and has high thermal stability;

the ethylene diamine tetra methylene sodium phosphate (EDTMPS) is a neutral product, is a nitrogen-containing organic polyphosphonate, has a certain corrosion inhibition effect, can be dissociated into 8 positive and negative ions in an aqueous solution, and is chelated with a plurality of metal ions to form a plurality of macromolecular reticular complexes, and has good chemical stability and temperature resistance.

Example 1

A preparation method of a barium sulfate scale inhibitor for oil fields is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 34% of polyepoxysuccinic acid, 16% of maleic acid-acrylic acid copolymer and 50% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, stirring the substances weighed in the step 1 for 20min until the substances are uniformly mixed to obtain the barium sulfate scale inhibitor.

Example 2

A preparation method of a barium sulfate scale inhibitor for oil fields is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 35% of polyepoxysuccinic acid, 30% of maleic acid-acrylic acid copolymer and 35% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, stirring the substances weighed in the step 1 for 20min until the substances are uniformly mixed to obtain the barium sulfate scale inhibitor.

Example 3

A preparation method of a barium sulfate scale inhibitor for oil fields is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 60% of polyepoxysuccinic acid, 10% of maleic acid-acrylic acid copolymer and 30% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, stirring the substances weighed in the step 1 for 15min until the substances are uniformly mixed to obtain the barium sulfate scale inhibitor.

Example 4

A preparation method of a barium sulfate scale inhibitor for oil fields is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 66% of polyepoxysuccinic acid, 16% of maleic acid-acrylic acid copolymer and 16% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, stirring the substances weighed in the step 1 for 20min until the substances are uniformly mixed to obtain the barium sulfate scale inhibitor.

Example 5

A preparation method of a barium sulfate scale inhibitor for oil fields is implemented according to the following steps:

step 1, weighing the following components in percentage by mass: 69% of polyepoxysuccinic acid, 8% of maleic acid-acrylic acid copolymer and 23% of ethylene diamine tetramethylene sodium phosphate, wherein the sum of the weight percentages of the components is 100%;

and 2, stirring the substances weighed in the step 1 for 10min until the substances are uniformly mixed to obtain the barium sulfate scale inhibitor.

The barium sulfate scale inhibitor for the oil field is prepared into 1g/L scale inhibitor solution by deionized water, and the performance of the barium sulfate scale inhibitor is evaluated by adopting a static scale inhibition method according to the petroleum and natural gas industry standard evaluation method for the performance of the scale inhibitor for the oil field (SY/T5673. sup. 1993), wherein the specific operation method comprises the following steps:

(1) preparing simulated formation water A and simulated injection water B, wherein the simulated formation water A comprises 75g/L of NaCl and BaCl₂·2H₂O6.6 g/L, simulated injection waterThe component B is NaCl 75g/L, Na₂SO₄ 8.00g/L；

(2) 150mL of distilled water is taken in a 250mL volumetric flask, and a certain volume of simulated formation water A (enabling Ba to be added) is accurately added²⁺185.5mg/L), accurately adding a certain volume of scale inhibitor solution (to make the content of the scale inhibitor be 60mg/L), standing for 10min, and adding a certain volume of simulated injection water B (to make SO) while shaking₄ ^2-The content is 270.5mg/L), the volume is determined, the solution is shaken up, the solution is transferred into a 250mL conical flask with a plug and a ground opening, the bottle plug is covered, the conical flask is placed into a 70 ℃ water bath kettle, the temperature is kept for half an hour, after the temperature is balanced, the bottle plug is opened to release air, then the bottle plug is covered, and the conical flask is placed in a 70 ℃ water bath for 16 hours;

(3) in the experiment, blank 1 is carried out simultaneously without adding scale inhibitor and with the same other steps;

(4) in the experiment, a blank 2 with the same steps is carried out simultaneously without adding a scale inhibitor and simulating injected water B;

(5) standing in 70 deg.C water bath for 16h, taking out ground conical flask, standing to room temperature, accurately transferring supernatant 25mL into conical flask, titrating Ba in solution by EDTA method²⁺And (4) content.

(6) Calculation of Scale inhibition Rate

The scale inhibition rate performance is characterized by scale inhibition rate, the larger the percentage value is, the better the scale inhibition performance is, and the scale inhibition rate E is calculated according to the following formula:

E＝(V₀-V₁)/(V₂-V₁)×100％

in the formula: v₀Titrating Ba in the solution after adding the scale inhibitor²⁺The volume of EDTA standard solution required for concentration, mL;

V₁titration of Ba in blank 1 solution²⁺The volume of EDTA standard solution required for concentration, mL;

V₂titration of Ba in blank 2 solution²⁺The volume of EDTA standard solution required for concentration, mL;

for the barium sulfate scale inhibitor in the formula and the barium sulfate (BaSO) on the market₄) The special scale inhibitor is compared by experimental test data which are shown in a table 1:

TABLE 1 comparison of technical parameters for antisludging agents

Product(s)	Formulation/manufacturer	pH value	Density g/cm3	Solid content%	The scale inhibition rate%
						Example 1	/	4.0	1.309	≥34.0	90.32
Example 2	/	2.5	1.291	≥37.0	94.68
						Example 3	/	4.5	1.351	≥36.0	98.84
Example 4	/	4.0	1.323	≥37.0	98.16
						Example 5	/	5.0	1.319	≥34.0	97.23
SN-1	Sailanchui chemical industry	1.0	1.109	16.4	73.49
						HY-2	Shandong Huayou water treatment	1.5	1.181	34.9	78.88

In addition, calcium sulfate (CaSO) of examples 1, 2, 3, 4 and 5 was also added₄) Evaluation of scale inhibition effect of (1) to (5) calcium sulfate (CaSO) was measured₄) The scale inhibition rates of (A) are 99.18%, 99.49%, 91.73%, 90.42% and 91.58%, respectively. By contrast, the sulfuric acid obtained by the inventionThe technical parameters of the barium scale inhibitor are superior to those of the common barium sulfate special scale inhibitor on the market at present, and the barium scale inhibitor also has good scale inhibition effect on calcium sulfate.