阅读说明：本技术 一种定点式自放热清蜡球及其制备工艺 (Fixed-point self-heat-release paraffin removal ball and preparation process thereof ) 是由 牛梦龙 牛红博 燕永利 尹丰丰 蔡雨秀 姜选选 史松 于 2020-07-02 设计创作，主要内容包括：一种定点式自放热清蜡球及其制备工艺,按质量份数计,包括明胶10-20份,聚丙烯酰胺10-20份,发热剂50-60份,缓速剂3-5份,有机酸催化剂10-15份以及助溶剂15-25份。本发明的清蜡体系是清蜡物质与油管里的水发生化学反应,产生的热量直接扩散到沉积在油管中的石蜡上,散失到地层的热量极少,因此可以避免热油洗井清蜡导致的热量损失,热效率很高。由于清蜡球配方中的所有物质都为水溶性,当清蜡球在油水混合物中溶解时,不会对原油的性质产生影响,对原油的后续加工不会产生影响。(A fixed-point self-heat-release paraffin removal ball and a preparation process thereof comprise, by mass, 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 50-60 parts of a heating agent, 3-5 parts of a retarder, 10-15 parts of an organic acid catalyst and 15-25 parts of a cosolvent. The paraffin removal system of the invention is characterized in that the paraffin removal substance and water in the oil pipe are subjected to chemical reaction, the generated heat is directly diffused to paraffin deposited in the oil pipe, and the heat dissipated to the stratum is very little, so that the heat loss caused by the wax removal of the hot oil well-flushing can be avoided, and the heat efficiency is very high. Because all substances in the paraffin removal ball formula are water-soluble, when the paraffin removal ball is dissolved in an oil-water mixture, the properties of the crude oil cannot be influenced, and the subsequent processing of the crude oil cannot be influenced.)

1. A fixed-point self-heat-release paraffin removal ball is characterized by comprising, by mass, 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 50-60 parts of a heat generating agent, 3-5 parts of a retarder and 10-15 parts of an organic acid catalyst.

2. The fixed-point self-heat-release paraffin removal ball as claimed in claim 1, wherein the heat generating agent comprises 25-30 parts by mass of ammonium chloride and 25-30 parts by mass of sodium nitrite, or the heat generating agent comprises 25-30 parts by mass of ammonium chloride and 25-30 parts by mass of potassium nitrite.

3. The fixed-point self-exothermic paraffin removal ball according to claim 1, wherein the retarder is one of sodium bicarbonate, sodium acetate, potassium carbonate and potassium bicarbonate; the organic acid catalyst is one of oxalic acid, citric acid and tartaric acid.

4. The fixed-point self-heat-release paraffin removal ball as claimed in claim 1, further comprising 15-25 parts by weight of a cosolvent.

5. The fixed-point self-exothermic paraffin removal ball according to claim 4, wherein the cosolvent is a mixture of sodium citrate and sodium bicarbonate; the paraffin removal ball also comprises a colorant, wherein the colorant accounts for 1 part when the gelatin accounts for 10-15 parts by weight.

6. The fixed-point self-heat-release paraffin removal ball according to claim 5, wherein the cosolvent comprises 5-10 parts by weight of sodium citrate and 10-15 parts by weight of sodium bicarbonate.

7. The fixed-point self-heat-release paraffin ball as claimed in claim 1, which comprises 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 25-30 parts of ammonium chloride, 25-30 parts of sodium nitrite, 2-5 parts of sodium acetate, 10-15 parts of oxalic acid, 5-10 parts of citric acid and 10-15 parts of sodium bicarbonate.

8. A preparation process of a fixed-point self-heat-release paraffin removal ball is characterized by comprising the following steps:

1) uniformly mixing 50-60 parts of a heating agent, 3-5 parts of a retarder and 10-15 parts of an organic acid catalyst in parts by weight, and performing compression molding to obtain a spherical object;

heating and melting 10-20 parts of gelatin, uniformly mixing with 10-20 parts of polyacrylamide, adding water, and stirring for 10-15min to obtain a mixture; the ratio of gelatin to water was (10-20) g: (10-15) mL;

2) and putting the spherical object into the mixture, wrapping the mixture on the surface of the small ball to form an outer layer, and extruding, cooling and molding by adopting a spherical mold with a circular groove to obtain the paraffin removal ball.

9. The process for preparing a fixed-point self-exothermic paraffin removal ball according to claim 8, wherein the diameter of the ball is 35-38 mm.

10. The process for preparing a fixed-point self-exothermic paraffin removal ball according to claim 8, wherein the thickness of the outer layer is 5-6 mm.

Technical Field

The invention belongs to the technical field of crude oil production, and relates to a fixed-point self-heat-release paraffin removal ball and a preparation process thereof.

Background

In the process of crude oil gathering and transportation, the oil temperature is reduced due to various reasons, when the oil temperature is reduced to the cloud point, wax crystals begin to be separated out and adsorbed on the pipe wall, the oil transportation pipe diameter is gradually reduced due to the irreversibility of wax precipitation and wax melting temperature, the wax precipitation of an external transportation pipeline is serious, the pressure of an external transportation pump is increased, the daily transportation capacity is reduced, and the crude oil production is directly restrained. Therefore, the wax deposition on the inner wall of the pipeline is removed, the normal production is ensured, and the output capacity is improved to an extent that the process is not slow. In order to remove the wax deposition in the pipeline, many methods are adopted, such as the utilization of wax-proofing agent, hot-washing wax-removing, microorganism wax-removing and preventing technology, mechanical wax-removing and chemical ball wax-removing, wherein the chemical ball wax-removing is adopted, so that the method is a good method which is simple, convenient, feasible and effective. However, the prior art has three defects; firstly, in the prior art, the paraffin removal ball is clamped in the running process of a pipeline, so that the flow resistance of crude oil is increased, even the pipeline is blocked, and the specific position of the paraffin removal ball cannot be determined for paraffin removal, so that the production is difficult; secondly, in order to remove wax deposition in the pipeline, people adopt a hot washing wax removal method, but the hot washing wax removal needs to be added with hot washing agent in batches, which wastes time and labor; thirdly, when wax is cleaned by hot washing, the thermal efficiency is low and the heat loss is serious.

Disclosure of Invention

In order to overcome the problems in the prior art, the invention aims to provide a fixed-point self-heat-release paraffin removal ball and a preparation process thereof, wherein the paraffin removal ball is put into use at one time, so that batch input in hot washing paraffin removal can be avoided, and manpower and material resources are saved; the paraffin removal ball has high thermal efficiency, and the generated heat is directly diffused to the paraffin deposited in the oil pipe, so that the heat dissipated to the stratum is very little, thereby avoiding the heat loss caused by the wax removal of the hot oil well-flushing and having high thermal efficiency.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a fixed-point self-heat-release paraffin removal ball comprises, by mass, 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 50-60 parts of a heating agent, 3-5 parts of a retarder and 10-15 parts of an organic acid catalyst.

The invention has the further improvement that the heat generating agent comprises 25-30 parts of ammonium chloride and 25-30 parts of sodium nitrite by mass parts, or the heat generating agent comprises 25-30 parts of ammonium chloride and 25-30 parts of potassium nitrite by mass parts.

The invention has the further improvement that the retarder is one of sodium bicarbonate, sodium acetate, potassium carbonate and potassium bicarbonate; the organic acid catalyst is one of oxalic acid, citric acid and tartaric acid.

The invention is further improved in that the cosolvent is a mixture of sodium citrate and sodium bicarbonate; the paraffin removal ball also comprises a colorant, wherein the colorant accounts for 1 part when the gelatin accounts for 10-15 parts by weight.

The invention has the further improvement that the cosolvent comprises 5-10 parts of citric acid and 10-15 parts of sodium bicarbonate by mass.

The invention has the further improvement that the paraffin removal ball also comprises 15 to 25 portions of cosolvent according to the mass portion.

The invention has the further improvement that the paraffin removal ball comprises 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 25-30 parts of ammonium chloride, 25-30 parts of sodium nitrite, 2-5 parts of sodium acetate, 10-15 parts of oxalic acid, 5-10 parts of sodium citrate and 10-15 parts of sodium bicarbonate.

A preparation process of a fixed-point self-heat-release paraffin removal ball comprises the following steps:

1) uniformly mixing 50-60 parts of a heating agent, 3-5 parts of a retarder and 10-15 parts of an organic acid catalyst in parts by weight, and performing compression molding to obtain a spherical object;

heating and melting 10-20 parts of gelatin, uniformly mixing with 10-20 parts of polyacrylamide, adding water, and stirring for 10-15min to obtain a mixture; the ratio of gelatin to water was (10-20) g: (10-15) mL;

2) and putting the spherical object into the mixture, wrapping the mixture on the surface of the small ball to form an outer layer, and extruding, cooling and molding by adopting a spherical mold with a circular groove to obtain the paraffin removal ball.

A further improvement of the invention is that the diameter of the ball is 35-38 mm.

A further development of the invention is that the outer layer has a thickness of 5 to 6 mm.

Compared with the prior art, the invention has the following beneficial effects:

1. the selected self-heat-release system has large heat release and high heat efficiency. The selected self-heat-release system is self-accelerating reaction, and compared with the existing hydrogen peroxide heat-release system and polyhydroxy aldehyde oxidation heat-release system, the heat-release system has large heat release. The paraffin removal system is characterized in that a paraffin removal substance and water in an oil pipe are subjected to chemical reaction, the generated heat is directly diffused to paraffin deposited in the oil pipe, and the heat dissipated to a stratum is very little, so that heat loss caused by the hot oil well washing and paraffin removal can be avoided, and the heat efficiency is very high.

2. High efficiency, energy saving and saving of electric energy and heat energy. The reaction is self-exothermic, so that the system does not need to be excited by other heat sources, and can be used independently without heating methods such as steam injection and the like.

3. Excellent environmental protection performance, and the chemical agent and the product thereof are safe, environment-friendly, nontoxic, tasteless and easy to treat. Because all substances in the paraffin removal ball formula are water-soluble, when the paraffin removal ball is dissolved in an oil-water mixture, the properties of the crude oil cannot be influenced, and the subsequent processing of the crude oil cannot be influenced.

Drawings

FIG. 1 is a graph showing the exothermic properties of the paraffin wax removal ball of example 1.

Figure 2 is the exothermic performance of the paraffin removal ball of example 2.

Figure 3 is the exothermic performance of the paraffin wax removal ball of example 3.

Figure 4 is the exothermic performance of the paraffin wax removal ball of example 4.

Figure 5 is the heat release performance of the paraffin removal ball of example 1 at different water flow pressures.

Figure 6 is the heat release performance of the paraffin removal ball of example 2 at different water flow pressures.

Figure 7 is the heat release performance of the paraffin removal ball of example 3 at different water flow pressures.

Figure 8 is the heat release performance of the paraffin removal ball of example 4 at different water flow pressures.

FIG. 9 is a schematic structural view of a fixed-point self-exothermic paraffin removal ball prepared in example 4.

Fig. 10 is a schematic view of an indoor simulation apparatus.

In the figure, 1-oil groove, 2-oil pump, 3-wax tube and 4-shell.

Detailed Description

In order to overcome the defects of the prior art, the invention provides a fixed-point self-heat-release paraffin removal ball formula and a preparation process thereof, and the paraffin removal ball is explained in several different aspects below.

The paraffin removal ball is a solid ball, and comprises, by weight, 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 50-60 parts of a heating agent, 3-5 parts of a retarder, 10-15 parts of an organic acid catalyst and 15-25 parts of a cosolvent.

Preferably, the heat generating agent comprises 25-30 parts of ammonium chloride and 25-30 parts of nitrite by weight.

The nitrite is one of sodium nitrite and potassium nitrite. The nitrite is preferably sodium nitrite.

The cosolvent is a mixture of sodium citrate and sodium bicarbonate.

Preferably, the cosolvent comprises 5-10 parts of sodium citrate and 10-15 parts of sodium bicarbonate in parts by weight.

The organic acid catalyst is one of oxalic acid, citric acid and tartaric acid.

Preferably, the organic acid catalyst is oxalic acid.

The retarder is one of sodium bicarbonate, sodium acetate, potassium bicarbonate and potassium carbonate.

Preferably, the retarder is sodium acetate.

Preferably, the paraffin removal ball comprises, by weight, 10-20 parts of gelatin, 10-20 parts of polyacrylamide, 25-30 parts of ammonium chloride, 25-30 parts of sodium nitrite, 2-5 parts of sodium acetate, 10-15 parts of oxalic acid, 5-10 parts of sodium citrate and 10-15 parts of sodium bicarbonate.

The paraffin removal ball mainly comprises two parts:

1) for the outer layer of the paraffin removal ball, the component of the outer layer of the paraffin removal ball is polyacrylamide which is used as the main component of the outer shell of the paraffin removal ball, and gelatin is used as a forming auxiliary agent of the polyacrylamide, so that the paraffin removal ball is easy to form, the mechanical property of the paraffin removal ball is improved, and the paraffin removal ball can be dissolved and softened to a certain extent; the shell component of the paraffin removal ball is completely soluble in a water phase, does not pollute crude oil, and simultaneously, the polyacrylamide serving as the shell component is also a flocculation component added in oilfield sewage treatment. Preferably, the thickness of the outer layer of the paraffin removal ball is about 5-6 mm; the surface of the paraffin removal ball is provided with a hydraulic stress groove which is a circular groove, and the diameter of the hydraulic stress groove is preferably 6-10 mm; preferably, it has a depth of 3-5 mm; the hydraulic stress groove is used as a bearing point of the water flow pressure of the oil-water mixture when the oil pipeline is blocked with wax, and provides a water environment for the wax removing ball. The water of the oil-water mixture in the oil pipeline is used as the initiator of the reaction, so that the paraffin removal ball can quickly generate self-heating reaction after meeting water.

When the outer layer is cooled and not formed, the wax cleaning ball is pressed by a spherical mould with a groove, and the wax cleaning ball is used for providing a water environment.

2) For the inner part of the paraffin removal ball, the inner core is a solid ball body with the diameter of 35-38 mm;

the inner core of the paraffin removal ball comprises a heating agent, an organic acid catalyst, a retarder and a cosolvent;

the heating agent is a mixture of sodium nitrite and ammonium chloride, and has the main function that when the mixture of the sodium nitrite and the ammonium chloride contacts with water in crude oil, a large amount of heat is generated by spontaneous reaction, and the dissolution of oil wax on the wall of an oil pipeline is accelerated;

the wax removal ball organic acid catalyst is oxalic acid, and the main function of the catalyst is to control the heat generation of an initiation system;

the retarder is sodium acetate and is mainly used for controlling the initiation time;

the cosolvent is sodium bicarbonate and sodium citrate, and has the main function of accelerating the dissolution rate of the paraffin removal ball;

preferably, the paraffin removal ball also comprises a colorant, and the colorant is a natural non-toxic water-soluble colorant and cannot pollute crude oil. As a wax removing ball coloring agent, the wax removing ball coloring agent mainly has the function of distinguishing wax removing balls with different heat release performances. When the gelatin is 10 to 15 parts by weight, the colorant is 1 part.

The gas generated by the reaction in the paraffin removal ball is inert gas nitrogen, so that the original pipeline cannot be corroded, and the generated gas flow can enhance the flowability of the crude oil. The exothermic agent does not pollute crude oil, and sodium chloride and water generated after the exothermic agent reacts can be completely dissolved in a water phase, and the exothermic agent does not pollute the crude oil.

2. The preparation process of the paraffin removal ball comprises the following steps:

1) according to the mass portion, 25-30 portions of ammonium chloride, 25-30 portions of sodium nitrite, 2-5 portions of sodium acetate, 10-15 portions of oxalic acid, 5-10 portions of sodium citrate and 10-15 portions of sodium bicarbonate are uniformly mixed, and are pressed and molded by a spherical mold with the diameter of 24-30mm to obtain the pellet.

2) Heating 10-20 parts of gelatin at a high temperature of 40-50 ℃ for melting, then uniformly mixing with 10-20 parts of polyacrylamide, adding 10-15mL of water, uniformly stirring while heating, wherein the stirring speed is 600r/min, and the stirring time is 10-15min, so that the gelatin becomes viscous and is in a certain flowing state, and thus a mixture is obtained.

3) Putting the prepared pellets into the mixture, wrapping the surfaces of the pellets with the mixture of gelatin and polyacrylamide to form an outer layer, cooling the outer layer to be in a semi-solidified state to facilitate the wrapping, extruding and cooling the outer layer to form the paraffin removal balls, wherein the thickness of the outer layer is 5-6mm, and the outer layer is formed by a spherical die with a diameter of 45-50mm and a circular groove.

The present invention will be described in further detail below with reference to different formulations for different high water cut and high oil cut crudes

When the oil pipeline meets the wax removal ball and meets water in the pipeline, the oil pipeline generates heat to cause local high temperature, so that wax deposited in the oil pipeline is quickly dissolved, and the fixed-point wax removal effect is further achieved. The paraffin removal ball can select a certain amount of paraffin removal balls to carry out fixed-point paraffin removal according to the length of a paraffin clamping pipe of an oil pipeline; the wax removal balls are put in one time, so that batch input in hot washing wax removal can be avoided, and manpower and material resources are saved; the paraffin removal ball has high thermal efficiency, and the generated heat is directly diffused to the paraffin deposited in the oil pipe, so that the heat dissipated to the stratum is very little, thereby avoiding the heat loss caused by the wax removal of the hot oil well-flushing and having high thermal efficiency.