A kind of imbibition type low corrosive sulfur deposition cleaning agent and its preparation method

Abstract

The application discloses a kind of imbibition type low corrosive sulfur deposition plugging cleaning agent and preparation method thereof, and relates to the technical field of oil and gas field development, comprising: cleaning main agent, the cleaning main agent is composed of sulfur-containing organic solvent and organic amine solvent;Auxiliary agent, the auxiliary agent is composed of hydroxyl-containing organic amine and benzene ring-containing organic amine;Imbibition agent.The imbibition type low corrosive sulfur deposition plugging cleaning agent and preparation method thereof proposed in the application have higher sulfur solubility, lower corrosion rate under the condition of not adding corrosion inhibitor, greatly improve cleaning efficiency.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field development technology, and in particular to a permeation-absorbing, low-corrosion sulfur deposition unblocking cleaning agent and its preparation method. Background Technology

[0002] In the development of high-sulfur natural gas fields, the deposition and blockage of elemental sulfur (S8) has become a core challenge restricting well productivity and increasing development costs. As gas reservoir development enters the middle and late stages, the decrease in formation pressure leads to a drop in temperature. When the reservoir temperature and pressure are lower than the washing conditions for elemental sulfur, gaseous sulfides (such as H2S) precipitate solid elemental sulfur, forming a dense deposit layer in the wellbore, near-wellbore formation, and gathering and transportation pipelines. This deposited sulfur has extremely strong adhesion and is difficult to remove by physical scraping or dissolve with a single solvent. Under temperature fluctuations, sulfur deposits undergo phase transitions, leading to dynamic changes in the blockage area and increasing the difficulty of cleaning. Moreover, the deposited sulfur reacts with iron ions in the formation water to form iron sulfide, exacerbating pipe corrosion and creating a vicious cycle of "blockage-corrosion-re-blockage". Traditional sulfur deposition cleaning technologies include physical cleaning methods, which are only suitable for local blockages and cannot handle micron-sized pores in near-wellbore formations or gathering and transportation pipelines with undulating surfaces; chemical dissolution methods can dissolve sulfur, but have problems such as high toxicity, high volatility, and insufficient permeability, and can severely corrode metal equipment; acid systems can partially dissolve sulfur, but are prone to hydrogen embrittlement and stress corrosion cracking, and cannot effectively penetrate dense sulfur deposits. Currently published sulfur deposition cleaning agent patents (such as CN1147823A and CN1147824A) mainly use organic solvents or strong oxidants, which have the following shortcomings: (1) Poor permeation performance: the solvent has high viscosity and high surface tension, making it difficult to penetrate into micron-sized pores through capillary force, and its ability to treat dense sulfur deposits is very limited; (2) High corrosion risk: strong acids or oxidizing solvents can easily damage wellbore metal equipment and shorten the life of facilities; (3) Weak environmental adaptability: it cannot adapt to the high temperature and high pressure environment of high sulfur gas fields, resulting in a decrease in cleaning efficiency.

[0003] Therefore, a penetrating, low-corrosion sulfur deposition unblocking cleaning agent and its preparation method were developed to solve the above problems. Summary of the Invention

[0004] This invention proposes a penetrating, low-corrosion sulfur deposition unblocking cleaning agent and its preparation method to solve the problems of poor penetrating performance, high corrosion risk, and weak environmental adaptability of existing products.

[0005] The present invention achieves the above objectives through the following technical solutions:

[0006] This invention discloses a penetrating, low-corrosion sulfur deposit unblocking cleaning agent, comprising:

[0007] The cleaning agent is composed of a sulfur-containing organic solvent and an organic amine solvent;

[0008] The additive is composed of an organic amine containing hydroxyl groups and an organic amine containing a benzene ring;

[0009] Absorbent.

[0010] Furthermore, the mass ratio of the cleaning agent, auxiliary agent and penetrant is 50~70:25~45:1~5;

[0011] Preferably, the mass ratio of the cleaning agent, auxiliary agent and penetrant is 63:35:2.

[0012] Furthermore, the penetrant is an amino-terminated polyether surfactant with the following molecular structure:

[0013] ;

[0014] Where n = 6~12.

[0015] Furthermore, the sulfur-containing organic solvent is one or more of 3-mercapto-1-propanol, 4-aminothiobenzamide, ethanethiol, 2-mercaptobenzothiazole, and thiourea;

[0016] Preferably, the sulfur-containing organic solvent is 3-mercapto-1-propanol and ethanethiol;

[0017] More preferably, the sulfur-containing organic solvent is ethanethiol.

[0018] Furthermore, the organic amine solvent is one or more of ethylamine, ethylenediamine, n-propylamine, n-butylamine, propanediamine, and pentamidine;

[0019] Preferably, the organic amine solvent is ethylamine, n-propylamine, n-butylamine, or pentamidine;

[0020] More preferably, the organic amine solvent is ethylamine.

[0021] Furthermore, the hydroxyl-containing organic amine is one or both of ethanolamine and ethylene glycolamine;

[0022] Preferably, the hydroxyl-containing organic amine is ethylene glycolamine.

[0023] Furthermore, the organic amine containing a benzene ring is one or both of aniline and diphenylamine;

[0024] Preferably, the organic amine containing a benzene ring is aniline.

[0025] Furthermore, the mass ratio of sulfur-containing organic solvent to organic amine solvent is 1~3:2~4;

[0026] Preferably, the mass ratio of sulfur-containing organic solvent to organic amine solvent is 2:3.

[0027] Furthermore, the mass ratio of hydroxyl-containing organic amines to benzene-ring-containing organic amines is 2~4:1~3;

[0028] Preferably, the mass ratio of hydroxyl-containing organic amines to benzene-ring-containing organic amines is 3:2.

[0029] The present invention also provides a method for preparing any of the described penetrating, low-corrosion sulfur deposition unblocking cleaning agents, comprising:

[0030] The cleaning agent is obtained by slowly adding a sulfur-containing organic solvent to an organic amine solvent under stirring conditions.

[0031] Then, the penetrant is added to the cleaning agent under stirring conditions and fully dissolved to obtain a cleaning agent containing the penetrant;

[0032] Finally, under stirring conditions, hydroxyl-containing organic amines and benzene-ring-containing organic amines were sequentially added to the cleaning agent containing the penetrant to obtain a penetrant-type low-corrosion sulfur deposition unblocking cleaning agent.

[0033] The beneficial effects of this invention are as follows:

[0034] The present invention proposes a penetrating, low-corrosion sulfur deposition unblocking cleaning agent and its preparation method, which has high sulfur solubility and low corrosion rate without the addition of corrosion inhibitors, thus greatly improving cleaning efficiency.

[0035] This invention is applicable to the removal of stubborn sulfur deposits in near-wellbore formations, wellbores, and gathering and transportation pipelines, and also has the characteristics of permeation and low corrosion. Attached Figure Description

[0036] Figure 1 The solubility histogram of deposited sulfur in Example 1 of this application;

[0037] Figure 2 The solubility histogram of deposited sulfur in Example 2 of this application;

[0038] Figure 3 The solubility histogram of deposited sulfur in Example 3 of this application;

[0039] Figure 4 The solubility histogram of deposited sulfur in Example 4 of this application;

[0040] Figure 5 The solubility histogram of deposited sulfur in Example 5 of this application;

[0041] Figure 6 The solubility histogram of deposited sulfur in Example 6 of this application;

[0042] Figure 7 The solubility histogram of deposited sulfur in Example 7 of this application;

[0043] Figure 8 The solubility histogram of deposited sulfur in Example 8 of this application;

[0044] Figure 9 The solubility histogram of deposited sulfur in Example 9 of this application;

[0045] Figure 10 The solubility histogram of deposited sulfur in Example 10 of this application;

[0046] Figure 11 Histogram of solubility of deposited sulfur in Example 11 of this application. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0049] The amino-terminated polyether surfactant used in this invention is amino-terminated polyether ZED-601 with product number D12000126 from Anaiji. All reagents not specified in this invention are commercially available.

[0050] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0051] Example 1

[0052] The cleaning agent formulation consists of 50% cleaning agent, 45% auxiliary agent and 5% penetrant. The cleaning agent is 3-mercapto-1-propanol and ethylamine in a mass ratio of 1:4; the auxiliary agent is ethanolamine and diphenylamine in a mass ratio of 2:3; and the penetrant is polyether surfactant PEA, which does not contain terminal amino groups but has the same number of ether bonds (n).

[0053] The cleaning agent is prepared as follows: First, 3-mercapto-1-propanol is slowly added to ethylamine at a mass ratio of 1:4 under stirring. Then, the penetrant polyether surfactant PEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethanolamine and diphenylamine are added to the cleaning agent containing the penetrant in a mass ratio of 2:3 under stirring to obtain the cleaning agent.

[0054] Deposited sulfur powder collected from gas field pipelines was pressed into a thin sheet of simulated deposited sulfur approximately 5 mm thick under a pressure of 0.5 MPa. The contact angle of the cleaning agent on the pressed sulfur sheet was measured using a dynamic contact angle meter (the result was 56.7°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 43.5 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the tubes were filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S = W0 - W1), in g / 100 mL. The results are shown in the attached figure. Figure 1 As shown; 200mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with the corrosion rate specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.052mm / a, which is less than the industry standard of 0.076mm / a). 200mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24h at 75℃ (the result was 3.7%) and the elongation at break reduction rate (the result was 9.6%).

[0055] Example 2

[0056] The cleaning agent formulation consists of 50% cleaning agent, 45% auxiliary agent and 5% penetrant. The cleaning agent is 3-mercapto-1-propanol and ethylamine in a mass ratio of 1:4; the auxiliary agent is ethanolamine and diphenylamine in a mass ratio of 2:3; and the penetrant is DPEA, an amino-terminated polyether surfactant.

[0057] The preparation method is as follows: First, 3-mercapto-1-propanol is slowly added to ethylamine at a mass ratio of 1:4 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethanolamine and diphenylamine are added to the cleaning agent containing the permeabilizer in a mass ratio of 2:3 under stirring to obtain the cleaning agent.

[0058] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 31.4°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 28.1 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 2 As shown; 200 mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with that specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.061 mm / a, which is less than the industry standard of 0.076 mm / a). 200 mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24 h at 75℃ (the result was 4.2%) and the elongation at break reduction rate (the result was 10.3%).

[0059] Example 3

[0060] The cleaning agent formula consists of 55% cleaning agent, 40% additives, and 5% penetrant, wherein the cleaning agent is...

[0061] The mixture consists of thiourea and n-propylamine in a mass ratio of 1:4; the additives are ethanolamine and diphenylamine in a mass ratio of 2:3; and the penetrant is DPEA, a terminal amino polyether surfactant.

[0062] The preparation method is as follows: First, 3-mercapto-1-propanol is slowly added to ethylamine at a mass ratio of 1:4 under stirring. Then, the percolating agent DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethanolamine and aniline are added to the cleaning agent containing the percolating agent in a mass ratio of 2:3 under stirring.

[0063] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 32.2°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 27.2 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 3 As shown; 200mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with the corrosion rate specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.058mm / a, which is less than the industry standard of 0.076mm / a). 200mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24h at 75℃ (the result was 3.4%) and the elongation at break reduction rate (the result was 9.2%).

[0064] Example 4

[0065] The cleaning agent formula consists of 50% cleaning agent, 45% additives, and 5% penetrant, wherein the cleaning agent is...

[0066] The mixture consists of 3-mercapto-1-propanol and ethylamine in a mass ratio of 1:4; the auxiliary agent is ethanolamine and aniline in a mass ratio of 2:3; and the penetrant is DPEA, a terminal amino polyether surfactant.

[0067] The preparation method is as follows: First, 3-mercapto-1-propanol is slowly added to ethylamine at a mass ratio of 1:4 under stirring. Then, the percolating agent DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethanolamine and aniline are added to the cleaning agent containing the percolating agent in a mass ratio of 2:3 under stirring.

[0068] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 28.3°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 24.3 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 4 As shown; 200mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with that specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.032mm / a, which is less than the industry standard of 0.076mm / a). 200mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24h at 75℃ (the result was 2.6%) and the elongation at break reduction rate (the result was 7.3%).

[0069] Example 5

[0070] The cleaning agent formula consists of 50% cleaning agent, 45% additives, and 5% penetrant, wherein the cleaning agent is...

[0071] The mixture consists of 3-mercapto-1-propanol and ethylamine in a mass ratio of 2:3; the auxiliary agent is ethanolamine and aniline in a mass ratio of 2:2; and the penetrant is DPEA, a terminal amino polyether surfactant.

[0072] The preparation method is as follows: First, 3-mercapto-1-propanol is slowly added to ethylamine at a mass ratio of 2:3 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethanolamine and aniline are added to the cleaning agent containing the permeabilizer in a mass ratio of 2:2 under stirring to obtain the cleaning agent.

[0073] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 27.6°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 24.1 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 5 As shown; 200 mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with that specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the corrosion rate of rubber was evaluated (the result measured at 75℃ was 0.034 mm / a, which is less than the industry standard of 0.076 mm / a). 200 mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break of the fluororubber were measured after soaking in the cleaning agent for 24 h at 75℃ (the result was 2.3%) and the reduction in elongation at break (the result was 7.1%).

[0074] Example 6

[0075] The cleaning agent formulation consists of 65% cleaning agent, 30% auxiliary agent and 5% penetrant. The cleaning agent is 3-mercapto-1-propanol and ethylamine in a mass ratio of 2:3; the auxiliary agent is ethanolamine and aniline in a mass ratio of 2:3; and the penetrant is DPEA, an amino-terminated polyether surfactant.

[0076] The preparation method is as follows: First, 3-mercapto-1-propanol is slowly added to ethylamine at a mass ratio of 2:3 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethanolamine and aniline are added to the cleaning agent containing the permeabilizer in sequence at a mass ratio of 2:3 under stirring to obtain the cleaning agent.

[0077] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 25.3°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 22.5 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 6 As shown; 200mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with the corrosion rate specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.036mm / a, which is less than the industry standard of 0.076mm / a). 200mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24h at 75℃ (the result was 2.7%) and the elongation at break reduction rate (the result was 7.4%).

[0078] Example 7

[0079] The cleaning agent formulation consists of 65% cleaning agent, 30% additives and 5% penetrant. The cleaning agent is ethanethiol and ethylamine in a mass ratio of 2:3; the additives are ethylene glycolamine and aniline in a mass ratio of 3:2; and the penetrant is DPEA, an amino-terminated polyether surfactant.

[0080] The preparation method is as follows: First, ethanethiol is slowly added to ethylamine at a mass ratio of 2:3 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethylene glycolamine and aniline are added to the cleaning agent containing the permeabilizer in a mass ratio of 3:2 under stirring to obtain the cleaning agent.

[0081] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 23.6°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 21.8 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 7 As shown; 200 mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with that specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.035 mm / a, which is less than the industry standard of 0.076 mm / a). 200 mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24 h at 75℃ (the result was 2.5%) and the elongation at break reduction rate (the result was 7.2%).

[0082] Example 8

[0083] The cleaning agent formulation consists of 63% cleaning agent, 35% additives and 2% penetrant. The cleaning agent is ethanethiol and ethylamine in a mass ratio of 2:3; the additives are ethylene glycolamine and aniline in a mass ratio of 3:2; and the penetrant is DPEA, an amino-terminated polyether surfactant.

[0084] The preparation method is as follows: First, ethanethiol is slowly added to ethylamine at a mass ratio of 2:3 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethylene glycolamine and aniline are added to the cleaning agent containing the permeabilizer in a mass ratio of 3:2 under stirring to obtain the cleaning agent.

[0085] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 22.1°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 20.5 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 8 As shown; 200 mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with the corrosion rate specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.032 mm / a, which is less than the industry standard of 0.076 mm / a). 200 mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24 h at 75℃ (the result was 2.2%) and the elongation at break reduction rate (the result was 6.8%).

[0086] Example 9

[0087] The cleaning agent formulation consists of 60% cleaning agent, 38% additives and 2% penetrant. The cleaning agent is ethanethiol and ethylamine in a mass ratio of 2:3; the additives are ethylene glycolamine and aniline in a mass ratio of 3:2; and the penetrant is DPEA, an amino-terminated polyether surfactant.

[0088] The preparation method is as follows: First, ethanethiol is slowly added to ethylamine at a mass ratio of 2:3 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethylene glycolamine and aniline are added to the cleaning agent containing the permeabilizer in a mass ratio of 3:2 under stirring to obtain the cleaning agent.

[0089] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 23.2°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 22.4 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 9 As shown; 200 mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with that specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the corrosion rate of rubber was evaluated (the result measured at 75℃ was 0.034 mm / a, which is less than the industry standard of 0.076 mm / a). 200 mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break of the fluororubber were measured after soaking in the cleaning agent for 24 h at 75℃ (the result was 2.3%) and the reduction in elongation at break (the result was 6.9%).

[0090] Example 10

[0091] The cleaning agent formulation consists of 70% cleaning agent, 25% auxiliary agent and 5% penetrant. The cleaning agent is 4-aminothiobenzamide and ethylenediamine in a mass ratio of 3:2; the auxiliary agent is ethylene glycolamine and aniline in a mass ratio of 4:1; and the penetrant is DPEA, a terminal amino polyether surfactant.

[0092] The preparation method is as follows: First, 4-aminothiobenzamide is slowly added to ethylamine at a mass ratio of 3:2 under stirring. Then, the permeabilizer DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethylene glycolamine and aniline are added to the cleaning agent containing the permeabilizer in a mass ratio of 4:1 under stirring to obtain the cleaning agent.

[0093] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 23.4°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 23.2 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 10 As shown; 200mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with the corrosion rate specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.033mm / a, which is less than the industry standard of 0.076mm / a). 200mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24h at 75℃ (the result was 2.3%) and the elongation at break reduction rate (the result was 7.0%).

[0094] Example 11

[0095] The cleaning agent formulation consists of 70% cleaning agent, 29% additives and 1% penetrant. The cleaning agent is 2-mercaptobenzothiazole and propanediol in a mass ratio of 3:2; the additives are ethylene glycolamine and aniline in a mass ratio of 4:1; and the penetrant is DPEA, an amino-terminated polyether surfactant.

[0096] The preparation method is as follows: First, 2-mercaptobenzothiazole is slowly added to ethylamine at a mass ratio of 3:2 under stirring. Then, the percolating agent DPEA is added to the cleaning agent under stirring and fully dissolved. Finally, ethylene glycolamine and aniline are added to the cleaning agent containing the percolating agent in a mass ratio of 4:1 under stirring to obtain the cleaning agent.

[0097] Deposited sulfur powder collected from gas field pipelines was pressed into thin sheets of approximately 5 mm under a pressure of 0.5 MPa to simulate deposited sulfur. The contact angle of the cleaning agent on the pressed sulfur sheets was measured using a dynamic contact angle meter (the result was 24.3°), and the surface tension of the cleaning agent was measured using a surface tension meter (the result was 24.4 mN / m). 100 mL of the prepared cleaning agent was placed in a stoppered colorimetric tube, and excess deposited sulfur powder was added at 25℃, 50℃, and 75℃ respectively. After standing for 120 min, the mixture was filtered and dried. The sulfur dissolution capacity of the cleaning agent was calculated using the differential method (S=W0-W1), in g / 100 mL. The results are shown in the attached figure. Figure 11 As shown; 200 mL of the prepared cleaning agent was taken and the corrosion rate of the steel sheet was determined according to the standard NACESP0775-2023 "Standard Operating Procedures for Preparation, Installation, Analysis and Interpretation of Corrosion Samples in Oilfield Operations". The corrosion rate was compared with that specified in the standard SY / T5329-2022 "Technical Requirements and Analytical Methods for Water Quality Indicators of Clastic Rock Reservoirs" and the rubber corrosion was evaluated (the result measured at 75℃ was 0.033 mm / a, which is less than the industry standard of 0.076 mm / a). 200 mL of the prepared cleaning agent was taken and the tensile strength reduction rate and elongation at break reduction rate of fluororubber were measured after soaking in the cleaning agent for 24 h at 75℃ (the result was 2.4%) and the elongation at break reduction rate (the result was 7.1%).

[0098] This invention meets the following technical specifications:

[0099] (1) Penetration efficiency: By combining surfactants and solvents, the contact angle between the cleaning agent and the deposited sulfur and rocks is reduced to below 30°, enabling spontaneous penetration into micron-sized pores and improving the cleaning of dense sulfur deposits;

[0100] (2) Solubility: The solubility of sulfur deposits is ≥90% within the range of room temperature to 150℃;

[0101] (3) Corrosion rate: In sulfur-containing formation water, the corrosion rate of carbon steel is ≤0.1mm / a. This invention has formed a deposited sulfur unblocking cleaning agent with strong penetration ability and low corrosivity by selecting solvents with low surface tension and anti-corrosion properties and well-compatible penetrants.

[0102] The advantages of this invention compared to the prior art are as follows:

[0103] 1. The sulfur-depositing unblocking cleaning agent disclosed in this invention mainly consists of sulfur-containing, amino-containing organic solvents and...

[0104] The cleaning agent, composed of amino-based penetrants, has a high sulfur solubility, reaching 82.75 g / 100 mL at 75°C.

[0105] 2. The sulfur-removing cleaning agent for unblocking deposits disclosed in this invention contains a certain proportion of aniline. Aniline not only...

[0106] It has the function of dissolving deposited sulfur, and its benzene ring has the effect of corrosion inhibition, so that the cleaning agent has a low corrosion rate without the addition of corrosion inhibitor. The corrosion rate of steel sheets at 75℃ can be as low as 0.032mm / a, which meets the requirement of ≤0.076mm / a in oilfield production. After 24 hours of soaking in fluororubber, the tensile strength reduction rate can be as low as 2.2%, and the elongation at break reduction rate can be as low as 6.8%.

[0107] 3. The penetrant contained in the sulfur deposit unblocking cleaning agent disclosed in this invention is a polyether type containing terminal amino groups.

[0108] Compared to polyether surfactants without terminal amino groups, surfactants can improve the wettability of cleaning agents with deposited sulfur, with a contact angle as low as 22.1° and a surface tension as low as 20.5 mN / m. This can increase the penetrating ability of cleaning agents to stubborn deposited sulfur, thereby improving cleaning efficiency.

[0109] 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 technical principles 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 penetrating, low-corrosion sulfur deposit unblocking cleaning agent, characterized in that, include: The cleaning agent is composed of a sulfur-containing organic solvent and an organic amine solvent; The additive is composed of an organic amine containing hydroxyl groups and an organic amine containing a benzene ring; Absorbent.

2. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The mass ratio of the cleaning agent, auxiliary agent and penetrant is 50~70:25~45:1~5; Preferably, the mass ratio of the cleaning agent, auxiliary agent and penetrant is 63:35:

2.

3. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The penetrant is an amino-terminated polyether surfactant, and its molecular structure is as follows: ； Where n = 6~12.

4. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The sulfur-containing organic solvent is one or more of 3-mercapto-1-propanol, 4-aminothiobenzamide, ethanethiol, 2-mercaptobenzothiazole, and thiourea; Preferably, the sulfur-containing organic solvent is 3-mercapto-1-propanol and ethanethiol; More preferably, the sulfur-containing organic solvent is ethanethiol.

5. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The organic amine solvent is one or more of ethylamine, ethylenediamine, n-propylamine, n-butylamine, propanediamine, and pentamidine; Preferably, the organic amine solvent is ethylamine, n-propylamine, n-butylamine, or pentamidine; More preferably, the organic amine solvent is ethylamine.

6. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The hydroxyl-containing organic amine is one or both of ethanolamine and ethylene glycolamine; Preferably, the hydroxyl-containing organic amine is ethylene glycolamine.

7. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The organic amine containing a benzene ring is one or both of aniline and diphenylamine; Preferably, the organic amine containing a benzene ring is aniline.

8. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The mass ratio of sulfur-containing organic solvents to organic amine solvents is 1~3:2~4; Preferably, the mass ratio of sulfur-containing organic solvent to organic amine solvent is 2:

3.

9. The penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to claim 1, characterized in that, The mass ratio of hydroxyl-containing organic amines to benzene-ring-containing organic amines is 2~4:1~3; Preferably, the mass ratio of hydroxyl-containing organic amines to benzene-ring-containing organic amines is 3:

2.

10. A method for preparing a penetrating, low-corrosion sulfur deposition unblocking cleaning agent according to any one of claims 1-9, characterized in that, include: The main cleaning agent is obtained by slowly adding a sulfur-containing organic solvent to an organic amine solvent under stirring conditions; Then, the penetrant is added to the cleaning agent under stirring conditions and fully dissolved to obtain a cleaning agent containing the penetrant; Finally, under stirring conditions, hydroxyl-containing organic amines and benzene-ring-containing organic amines were sequentially added to the cleaning agent containing the penetrant to obtain a penetrant-type low-corrosion sulfur deposition unblocking cleaning agent.

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