Elemental sulfur particle dispersant and method for preparing the same

Abstract

The present application relates to the technical fields of oil and gas field safety transportation, and more particularly to a single sulfur particle dispersant and a preparation method thereof.The single sulfur particle dispersant comprises an anionic surfactant, a zwitterionic surfactant, an inorganic salt and a solvent.By adjusting the synergy and compatibility between the surfactant and the inorganic salt, the problems of easy evaporation, flammability and explosiveness of the existing sulfur dissolving agent are solved, the use of the compounded single sulfur particle dispersant is wider than that of a single surfactant, the performance is better, and the application cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of safe transportation technology in oil and gas fields, and in particular to a particulate sulfur dispersant and its preparation method. Background Technology

[0002] Currently, sulfur deposition has seriously affected the safe operation of high-sulfur gas field gathering and transportation systems. In oilfields, highly toxic, corrosive, and costly sulfur solvents remain the most direct and effective method for mitigating sulfur deposition. Sulfur solvents mainly include physical and chemical solvents. Physical solvents utilize the principle of "like dissolves like" to dissolve sulfur in a solvent. Common physical solvents include benzene compounds, cyclohexene, cyclohexane, and alcohols. These physical solvents are generally toxic, highly corrosive, and flammable. If the physical solvent has a molecular structure similar to S8, it can also greatly promote sulfur dissolution, such as anhydrous ethanol, carbon disulfide, and diesel fuel. Physical solvents are generally used to treat medium-sized sulfur deposits; when the sulfur deposition is large, chemical solvents are required. Common chemical sulfur solvents include dimethyl disulfide (DMDS), N,N-dimethylformamide (DMF), and ethanolamine. Among them, DMDS has become a major component of existing sulfur solvents due to its good sulfur-dissolving effect. However, DMDS has serious side effects: strong irritation, high volatility, foul odor, and high toxicity.

[0003] Furthermore, existing sulfur dissolving agents only intervene after sulfur deposition has occurred, resulting in a "post-treatment" approach with drawbacks such as high costs and significant safety hazards. Therefore, there is an urgent need to develop a "source control" agent that proactively prevents sulfur deposition by inhibiting the agglomeration and growth of sulfur particles and promoting their dispersion. Surfactants show promising application prospects in dispersing solid particles. Their mechanism of action is as follows: the hydrophobic groups of the surfactant adsorb onto the surface of sulfur particles, while the hydrophilic groups bind to water molecules. On the one hand, this reduces surface tension, significantly improving the wettability of the solid particle surface; on the other hand, after adsorption, the surfactant charges the surface of the solid particles, forming an electric double layer, which inhibits particle aggregation through electrostatic repulsion. In practical engineering, the purification cost of a single surfactant is high and the process is complex. Therefore, surfactants are usually compounded to enhance their performance, thereby reducing usage costs, expanding application range, and improving environmental performance. Therefore, how to provide a novel compound surfactant system as a dispersant for elemental sulfur particles has become a pressing technical problem to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to provide a dispersant for elemental sulfur particles and its preparation method, so as to solve the problems of high toxicity, strong corrosiveness and high cost of existing sulfur dissolving agents.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a dispersant for elemental sulfur particles, comprising the following components in parts by weight: 16-145 parts of anionic surfactant, 5-35 parts of amphoteric surfactant, 7-70 parts of inorganic salt, and 800-2000 parts of solvent.

[0006] Optionally, the anionic surfactant is sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, linear alkylbenzene sulfonate, or sodium fatty alcohol ether sulfate.

[0007] Optionally, the zwitterionic surfactant is dodecyl dimethylamine oxide.

[0008] Optionally, the inorganic salt is calcium chloride and sodium chloride.

[0009] Optionally, the solvent is water.

[0010] Optionally, the components include the following parts by weight: 4-40 parts sodium dodecylbenzenesulfonate, 4-40 parts sodium dodecyl sulfate, 3-25 parts linear alkylbenzene sulfonate, 5-40 parts sodium fatty alcohol ether sulfate, 5-35 parts dodecyl dimethylamine oxide, 4-30 parts calcium chloride, 3-40 parts sodium chloride, and 800-2000 parts solvent.

[0011] The present invention also provides a method for preparing the above-mentioned elemental sulfur particle dispersant, characterized in that an anionic surfactant, an amphoteric surfactant, an inorganic salt and a solvent are mixed and reacted to obtain the elemental sulfur particle dispersant.

[0012] Optionally, the reaction temperature is 25~45℃, the rotation speed is 400~600 r / min, and the time is 2~5h.

[0013] Optionally, after the reaction is complete, the mixture is allowed to stand for 15-20 hours, and then sieved to obtain a dispersant of elemental sulfur particles with a particle size of less than or equal to 500 mesh.

[0014] The present invention also provides the application of the above-mentioned elemental sulfur particle dispersant in the development of high sulfur gas fields.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The elemental sulfur particle dispersant disclosed in this invention is mainly composed of anionic surfactants, amphoteric surfactants, inorganic salts, and distilled water. By adjusting the synergy and compatibility between the surfactants and inorganic salts, the problems of volatility, flammability, and explosiveness of existing sulfur solvents are solved. Furthermore, the compounded elemental sulfur particle dispersant has a wider range of applications and better performance than that of a single surfactant, while also reducing application costs.

[0016] This invention fully leverages the advantages of sodium dodecylbenzenesulfonate and sodium dodecyl sulfate in their excellent wettability and dispersibility of sulfur particles. The surfactants used in this invention exhibit high solubility, excellent synergistic effects, low cost, environmental friendliness, and effective dispersion of sulfur particles. Furthermore, the addition of inorganic salts also addresses sulfur deposition issues, further enhancing the dispersion of sulfur particles. Attached Figure Description

[0017] Figure 1 This is a flowchart of a pipe flow experiment. Detailed Implementation

[0018] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0019] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0020] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0021] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This application specification and embodiments are merely exemplary.

[0022] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0023] All raw materials used in this invention can be obtained commercially or prepared using existing technologies.

[0024] This invention provides a dispersant for elemental sulfur particles, comprising the following components in parts by weight: 16-145 parts of anionic surfactant, 5-35 parts of amphoteric surfactant, 7-70 parts of inorganic salt, and 800-2000 parts of solvent.

[0025] In this invention, the elemental sulfur particle dispersant comprises 16 to 145 parts of anionic surfactant, preferably 20 to 100 parts, more preferably 40 to 80 parts, and even more preferably 50 to 60 parts.

[0026] In this invention, the elemental sulfur particle dispersant comprises 5 to 35 parts of a zwitterionic surfactant, preferably 10 to 30 parts, more preferably 15 to 25 parts, and even more preferably 20 to 22 parts.

[0027] In this invention, the elemental sulfur particle dispersant comprises 7 to 70 parts of inorganic salt, preferably 10 to 60 parts, more preferably 20 to 50 parts, and even more preferably 30 to 40 parts.

[0028] In this invention, the elemental sulfur particle dispersant comprises 800-2000 parts of solvent, preferably 1000-1800 parts, more preferably 1300-1600 parts, and even more preferably 1400-1500 parts.

[0029] In this invention, the anionic surfactant is sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, linear alkylbenzenesulfonate, and sodium fatty alcohol ether sulfate.

[0030] In this invention, the zwitterionic surfactant is dodecyl dimethylamine oxide.

[0031] In the embodiments of the present invention, the sodium dodecylbenzenesulfonate and dodecyl dimethylamine oxide are of analytical grade (AR); the sodium dodecyl sulfate is of chemically pure grade (CP); and the linear alkylbenzenesulfonate is of grade 80-95%.

[0032] In this invention, the inorganic salts are calcium chloride and sodium chloride.

[0033] Combining anionic surfactants, amphoteric surfactants, and inorganic salts can effectively reduce the surface tension of the solution and increase the wettability of the solution for sulfur powder, thereby further dispersing the sulfur particles.

[0034] In this invention, the solvent is water.

[0035] In this invention, the components include the following parts by weight: 4-40 parts sodium dodecylbenzenesulfonate, 4-40 parts sodium dodecyl sulfate, 3-25 parts linear alkylbenzenesulfonate, 5-40 parts sodium fatty alcohol ether sulfate, 5-35 parts dodecyl dimethylamine oxide, 4-30 parts calcium chloride, 3-40 parts sodium chloride, and 800-2000 parts solvent.

[0036] In this invention, the elemental sulfur particle dispersant comprises 4 to 40 parts of sodium dodecylbenzenesulfonate, preferably 5 to 35 parts, more preferably 10 to 30 parts, and even more preferably 15 to 25 parts.

[0037] In this invention, the elemental sulfur particle dispersant comprises 4 to 40 parts of sodium dodecyl sulfate, preferably 5 to 35 parts, more preferably 10 to 30 parts, and even more preferably 15 to 25 parts.

[0038] In this invention, the elemental sulfur particle dispersant comprises 3 to 25 parts of linear alkylbenzene sulfonate, preferably 5 to 20 parts, more preferably 10 to 15 parts, and even more preferably 12 to 14 parts.

[0039] In this invention, the elemental sulfur particle dispersant comprises 5-40 parts of sodium fatty alcohol ether sulfate, preferably 10-35 parts, more preferably 15-30 parts, and even more preferably 20-25 parts.

[0040] In this invention, the elemental sulfur particle dispersant comprises 5-35 parts of dodecyl dimethylamine oxide, preferably 5-30 parts, more preferably 10-25 parts, and even more preferably 15-20 parts.

[0041] In this invention, the elemental sulfur particle dispersant comprises 4 to 30 parts of calcium chloride, preferably 5 to 25 parts, more preferably 10 to 20 parts, and even more preferably 15 to 16 parts.

[0042] In this invention, the elemental sulfur particle dispersant comprises 3-40 parts of sodium chloride, preferably 5-35 parts, more preferably 10-30 parts, and even more preferably 15-25 parts.

[0043] In this invention, the elemental sulfur particle dispersant comprises 800-2000 parts of solvent, preferably 1000-1800 parts, more preferably 1300-1600 parts, and even more preferably 1400-1500 parts.

[0044] The present invention also provides a method for preparing the above-mentioned elemental sulfur particle dispersant, characterized in that an anionic surfactant, an amphoteric surfactant, an inorganic salt and a solvent are mixed and reacted to obtain the elemental sulfur particle dispersant.

[0045] In an embodiment of the present invention, sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, and distilled water are first mixed to obtain a first mixed product; then the first mixed product is mixed with linear alkylbenzene sulfonate, sodium fatty alcohol ether sulfate, and dodecyl dimethylamine oxide to obtain a second mixed product; then the second mixed product is mixed with calcium chloride and sodium chloride to obtain a third mixed product; finally, the third mixed product is subjected to a constant temperature stirring reaction to obtain a dispersant for elemental sulfur particles.

[0046] In this invention, the reaction temperature is 25~45 ℃, preferably 30~40 ℃, more preferably 35~36 ℃; the rotation speed is 400~600 r / min, preferably 450~550 r / min, more preferably 460~500 r / min; and the time is 2~5 h, preferably 2.5~4.5 h, more preferably 3~4 h.

[0047] In this invention, after the reaction is completed, the mixture is allowed to stand for 15-20 h, preferably 16-19 h, and more preferably 17-18 h, and then sieved to obtain a dispersant of elemental sulfur particles with a particle size of less than or equal to 500 mesh.

[0048] The present invention also provides the application of the above-mentioned elemental sulfur particle dispersant in the development of high sulfur gas fields.

[0049] In practical applications, elemental sulfur particle dispersants are added based on the concentration of elemental sulfur in high-sulfur gas fields, the particle size distribution, and the required dispersion stability.

[0050] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0051] Example 1 The elemental sulfur particle dispersant is composed of the following components in parts by weight: 12 parts sodium dodecylbenzenesulfonate, 12 parts sodium dodecyl sulfate, 15 parts linear alkylbenzene sulfonate, 15 parts sodium fatty alcohol ether sulfate, 10 parts dodecyl dimethylamine oxide, 14 parts calcium chloride, 15 parts sodium chloride, and 1200 parts distilled water.

[0052] The preparation method of the elemental sulfur particle dispersant described in this embodiment includes the following steps: Under conditions of 35°C, the above-mentioned sodium dodecylbenzenesulfonate, sodium dodecyl sulfate and distilled water were mixed in the first mixture to obtain the first mixed product; The product of the first mixture is then mixed with linear alkylbenzene sulfonate, sodium fatty alcohol ether sulfate, and dodecyl dimethylamine oxide to obtain the second mixed product. The second mixture is mixed with calcium chloride and sodium chloride to obtain a third mixture. Finally, the third mixture was placed on a thermostatic magnetic stirrer and stirred at a temperature of 35 ℃ and a speed of 500 r / min for 3 h to ensure thorough mixing and reaction. After stirring, the mixture was allowed to stand for 15 h and then sieved through a 500-mesh standard sieve to obtain the elemental sulfur particle dispersant.

[0053] Example 2 The only difference from Example 1 is that sodium dodecylbenzenesulfonate is 15 parts, calcium chloride is 16 parts, and sodium fatty alcohol ether sulfate is 20 parts.

[0054] Example 3 The only difference from Example 1 is that sodium dodecylbenzenesulfonate is 20 parts, sodium dodecyl sulfate is 15 parts, and dodecyl dimethylamine oxide is 16 parts.

[0055] Example 4 The only difference from Example 1 is that sodium dodecylbenzenesulfonate is 18 parts and sodium chloride is 20 parts.

[0056] Comparative Example 1 The only difference from Example 1 is that it does not contain calcium chloride and sodium chloride.

[0057] Comparative Example 2 The only difference from Example 1 is that it does not contain dodecyl dimethylamine oxide.

[0058] Comparative Example 3 The only difference from Example 1 is that it does not contain sodium dodecylbenzenesulfonate or sodium dodecyl sulfate.

[0059] Comparative Example 4 The only difference from Example 1 is that the amount of calcium chloride is 40 parts and the amount of sodium chloride is 50 parts.

[0060] Comparative Example 5 The only difference from Example 1 is that the amount of dodecyl dimethylamine oxide is 50 parts.

[0061] Test case 1. Tube Flow Experiment In this example, a self-built pipe flow experimental setup was used to verify the mitigation effect of elemental sulfur particle dispersant on sulfur deposition. Sublimated sulfur from Chengdu Kelon Company was selected for the pipe flow experiment, with an elemental sulfur content ≥99.5%. Sulfur particles with a diameter range of 150μm~200μm were separated using 80-mesh and 100-mesh standard sieves. The mitigation effect of the elemental sulfur particle dispersant on sulfur deposition was analyzed and compared with the sulfur deposition under conditions of gas phase only and gas phase-distilled water interaction.

[0062] The specific steps of the tube flow experiment are as follows: (1) According to Figure 1 Follow the procedure shown, connect the equipment, and check for airtightness.

[0063] (2) Deposition experiment of sulfur particles in the gas phase A certain mass of sulfur powder is added to the sulfur particle injection device. The amount of sulfur particles used is 12 times that of the elemental sulfur particle dispersant. The gas booster pump is turned on, and its speed is adjusted to control the gas flow rate in the straight pipe test section to 5 m / s. The sulfur particle injection device is then turned on, ensuring that the sulfur particles enter the straight pipe test section at a certain mass flow rate. As the gas flows in the pipe, the sulfur particles are carried by the gas and flow out of the pipe into the cyclone separator for gas-solid two-phase separation. After the sulfur particles have flowed fully in the pipe for 30 minutes, the gas booster pump and the sulfur particle injection device are turned off.

[0064] (3) Deposition experiment of sulfur particles in gas phase-distilled water Add the same mass of sulfur powder to the sulfur particle injection device. Turn on the gas booster pump and control the gas flow rate in the straight pipe test section to 5 m / s. Turn on the liquid booster pump and spray distilled water into the straight pipe test section. After the sulfur particles have flowed fully in the straight pipe test section for 30 minutes, turn off the gas booster pump, the sulfur particle injection device, and the liquid booster pump.

[0065] (4) Deposition experiment of sulfur particles in gas phase-elemental sulfur particle dispersant.

[0066] The difference between this experiment and experiment (3) is that the added liquid phase components are different, and the amount of sulfur particles used is 12 times that of elemental sulfur particle dispersant. In this experiment, the liquid booster pump was turned on to spray the elemental sulfur particle dispersant into the straight pipe test section.

[0067] After the three sets of experiments were completed, the straight pipe test section was removed, and distilled water was injected into it to rinse the deposited sulfur on the inner wall of the pipe. The resulting solution containing sulfur components was poured into a standard sieve whose initial mass had been recorded, and then placed in a high-temperature drying oven at 100 ℃ for 16 h to completely dry the sulfur powder, followed by shaking. After the sieving operation was completed, the standard sieves of different mesh sizes were weighed sequentially, and the mass of sulfur particles in the standard sieves of different mesh sizes was recorded. The weighing results are shown in Table 1.

[0068] This paper uses a weighted average calculation method based on equidistant segmentation to determine the average particle size of sulfur particles. The median value of each particle size range is taken as the representative particle size, multiplied by its respective proportion, and the average particle size is determined by summing. The average particle size of sulfur particles is obtained by the following formula, and the calculation results are shown in Table 1: In the formula: —The mass fraction of sulfur particles in different particle size ranges; —The mass of sulfur particles in different size ranges.

[0069] The average sulfur particle size is calculated using the following formula: In the formula: —The average particle size of the sulfur particles; —Particle size > 150 μm; —Particle size between 125μm and 150μm; —Particle size between 100μm and 125μm; —Particle size between 90μm and 100μm; —Particle size is between 75μm and 90μm; —Particle size < 75 μm.

[0070] Table 1. Distribution of sulfur particles in different experiments

[0071] As can be seen from Table 1, the amount of sulfur deposited after adding the elemental sulfur particle dispersant is reduced compared with the amount of sulfur deposited in the gas-solid and gas-solid-distilled water states, and the sulfur particles are mainly distributed in the chassis, indicating that the technical solution provided by the present invention is effective.

[0072] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A particulate dispersant for elemental sulfur, characterized in that, It comprises the following components in parts by weight: 16-145 parts of anionic surfactant, 5-35 parts of amphoteric surfactant, 7-70 parts of inorganic salt, and 800-2000 parts of solvent.

2. The elemental sulfur particle dispersant according to claim 1, characterized in that, The anionic surfactant is sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, linear alkylbenzene sulfonate, and sodium fatty alcohol ether sulfate.

3. The elemental sulfur particle dispersant according to claim 1, characterized in that, The zwitterionic surfactant is dodecyl dimethylamine oxide.

4. The elemental sulfur particle dispersant according to claim 1, characterized in that, The inorganic salts are calcium chloride and sodium chloride.

5. The elemental sulfur particle dispersant according to claim 1, characterized in that, The solvent is water.

6. The elemental sulfur particle dispersant according to claim 1, characterized in that, The product comprises the following components in parts by weight: sodium dodecylbenzenesulfonate 4-40 parts, sodium dodecyl sulfate 4-40 parts, linear alkylbenzene sulfonate 3-25 parts, fatty alcohol ether sulfate 5-40 parts, dodecyl dimethylamine oxide 5-35 parts, calcium chloride 4-30 parts, sodium chloride 3-40 parts, and solvent 800-2000 parts.

7. The method for preparing the elemental sulfur particle dispersant according to any one of claims 1 to 6, characterized in that, Anionic surfactant, amphoteric surfactant, inorganic salt and solvent are mixed and reacted to obtain elemental sulfur particle dispersant.

8. The elemental sulfur particle dispersant according to claim 7, characterized in that, The reaction temperature is 25~45℃, the rotation speed is 400~600 r / min, and the time is 2~5h.

9. The elemental sulfur particle dispersant according to claim 7, characterized in that, After the reaction is complete, let it stand for 15-20 hours, then sieve it to obtain a dispersant of elemental sulfur particles with a particle size of less than or equal to 500 mesh.

10. The application of the elemental sulfur particulate dispersant according to any one of claims 1 to 6 in the development of high-sulfur gas fields.

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