Surfactant composition, foam scrubbing agent, application of foam scrubbing agent and method for removing effusion

Abstract

The invention relates to the technical field of surfactants and pipeline transportation, and provides a surfactant composition which comprises fatty acid ester polyether, fatty acid ester polyether sulfate and succinic acid sulfonate. The composition has excellent foamability at a high airflow velocity, so that the composition has excellent foam drainage performance when being applied to a gas transmission pipeline, stable operation of the gas transmission pipeline can be ensured, and meanwhile, the foam drainage agent has relatively weak thermal stability, is easy to hydrolyze and lose efficacy under an acidic condition, and can be applied to the gas transmission pipeline. By adopting the foam scrubbing agent, liquid can be stably drained within 2 hours, the foam scrubbing agent loses efficacy after the liquid reaches a natural gas master station, and defoaming gas-liquid separation is realized.

Description

Technical Field

[0001] The present invention relates to the technical fields of surfactants and pipeline transportation, and particularly relates to a surfactant composition, a foam drainage agent and its application, and a method for removing accumulated liquid. Background Art

[0002] The areas where the southwestern gas fields in China are located are crisscrossed by ravines and have undulating terrain. With the deepening of development, the water production of gas wells gradually increases, the liquid holdup in pipelines rises, and the accumulation of liquid intensifies. On the one hand, the accumulation of liquid in pipelines will lead to low pipeline transportation efficiency and high upstream transmission pressure. When the pressure reaches the threshold, it will cause the pipeline to shut down, resulting in system fluctuations and affecting production. On the other hand, a large amount of accumulated liquid in the pipeline is prone to water hammer, seriously affecting the safe operation of the pipeline. Taking the Puguang Gas Field as an example, at present, the method of periodically using pigging for batch treatment is adopted to remove the accumulated liquid. However, as the accumulation of liquid becomes more and more serious, the batch treatment cycle of some pipelines is only 4 days, which not only increases the on-site workload, but also requires shutting down the well when using pigging, resulting in system fluctuations and affecting production.

[0003] A foam drainage agent injection device is proposed in CN202010775347.9 to inject the foam drainage agent to remove the accumulated liquid in the pipeline. However, more foam in the pipeline will affect the subsequent gas-liquid separation, so the selection of a suitable foam drainage agent is the key. Summary of the Invention

[0004] The purpose of the present invention is to overcome the problem in the prior art that the accumulation of liquid in the pipeline during the transportation of sour gas-containing natural gas causes the increase of the export pressure, thereby affecting the natural gas production. The present invention provides a surfactant composition, a foam drainage agent and its application, and a method for removing accumulated liquid. The foam drainage agent is used to remove the accumulated liquid in the pipeline and has excellent foam drainage performance.

[0005] To achieve the above purpose, in the first aspect of the present invention, a surfactant composition is provided, which includes: fatty acid ester polyether, fatty acid ester polyether sulfate, and sulfosuccinate.

[0006] In the second aspect of the present invention, a foam drainage agent is provided, which includes the surfactant composition described in the present invention and water.

[0007] In the third aspect of the present invention, an application of the foam drainage agent described in the present invention in removing the accumulated liquid in the pipeline is provided.

[0008] In the fourth aspect of the present invention, a method for removing accumulated liquid is provided, which includes: injecting the foam drainage agent described in the present invention into the pipeline to form foam and remove the accumulated liquid in the pipeline.

[0009] Through the above technical solution, the foam drainage agent of the present invention has excellent foaming property at high gas flow rate, so that it has excellent foam drainage performance when applied in the gas transmission pipeline, which can ensure the stable operation of the gas transmission pipeline. At the same time, the foam drainage agent has weak thermal stability under acidic conditions and can be hydrolyzed and inactivated. The foam drainage agent can stably drain liquid within 2 hours, and the foam drainage agent becomes ineffective after the liquid reaches the natural gas terminal station, realizing defoaming and gas-liquid separation.

[0010] The present invention adopts a method of removing liquid accumulation in the pipeline with foam. Foam is a dispersion system in which gas is dispersed in liquid. After the foam is formed, the fluid density is greatly reduced, so that the liquid accumulation in the pipeline can be removed at a lower gas flow rate. Detailed implementation mode

[0011] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0012] In a first aspect, a surfactant composition is provided, which comprises: fatty acid ester polyether, fatty acid ester polyether sulfate, and sulfosuccinate.

[0013] According to a preferred embodiment of the present invention, the molar ratio of fatty acid ester polyether, fatty acid ester polyether sulfate, and sulfosuccinate is 1:0.1-10:0.1-5.

[0014] In the present invention, the types of the fatty acid ester polyether have a relatively wide selection range. According to a preferred embodiment of the present invention, the structural formula of the fatty acid ester polyether is shown in formula (1).

[0015]

[0016] In formula (1), R 1 is a saturated or unsaturated fatty group with C10-C18, m is a number from 0 to 7, and n is a number from 5 to 20.

[0017] In the present invention, the types of the fatty acid ester polyether sulfate have a relatively wide selection range. According to a preferred embodiment of the present invention, the structural formula of the fatty acid ester polyether sulfate is shown in formula (2).

[0018]

[0019] In formula (2), R 2is a saturated or unsaturated fatty group having 10 to 18 carbon atoms, p is a number from 0 to 7, q is a number from 2 to 10, and M + is any one of alkali metal ions or ammonium ions.

[0020] In the present invention, the types of sulfosuccinates have a relatively wide selection range. For example, they can be at least one of alkali metal salts, alkaline earth metal salts, and ammonium salts of sulfosuccinic acid. According to a preferred embodiment of the present invention, the sulfosuccinate is sodium sulfosuccinate.

[0021] According to a preferred embodiment of the present invention, the fatty acid ester polyether is selected from at least one of the compounds represented by Formula (1-1), Formula (1-2), Formula (1-3), Formula (1-4), Formula (1-5), and Formula (1-6);

[0022] Among them, Formula (1-1): In Formula (1), R 1 is C 12 H 25 , m = 7, n = 15;

[0023] Formula (1-2): In Formula (1), R 1 is C 10 H 21 , m = 1, n = 10;

[0024] Formula (1-3): In Formula (1), R 1 is C 12 H 25 , m = 0, n = 5;

[0025] Formula (1-4): In Formula (1), R 1 is C 16 H 33 , m = 0, n = 20;

[0026] Formula (1-5): In Formula (1), R 1 is C 18 H 33 , m = 1, n = 15;

[0027] Formula (1-6): In Formula (1), R 1 is C 10 H 21 , m = 2, n = 15.

[0028] According to a preferred embodiment of the present invention, the fatty acid ester polyether is selected from the composition of the compounds represented by Formula (1-1) and Formula (1-2), wherein the molar ratio of the compounds represented by Formula (1-1) and Formula (1-2) is 0.3 - 2:1.

[0029] According to a preferred embodiment of the present invention, the fatty acid ester polyether sulfate is selected from at least one of the compounds represented by formula (2-1), formula (2-2), formula (2-3), formula (2-4), formula (2-5), formula (2-6), and formula (2-7); wherein,

[0030] Formula (2-1): In formula (2), R 2 is C 12 H 25 , p = 7, q = 15;

[0031] Formula (2-2): In formula (2), R 2 is C 10 H 21 , p = 5, q = 8;

[0032] Formula (2-3): In formula (2), R 2 is C 16 H 33 , p = 0, q = 5;

[0033] Formula (2-4): In formula (2), R 2 is C 18 H 33 , p = 0, q = 10;

[0034] Formula (2-5): In formula (2), R 2 is C 12 H 25 , p = 1, q = 2;

[0035] Formula (2-6): In formula (2), R 2 is C 12 H 25 , p = 7, q = 7;

[0036] Formula (2-7): In formula (2), R 2 is C 10 H 21 , p = 0, q = 3.

[0037] The second aspect of the present invention provides a foam drainage agent, which includes the surfactant composition of the present invention and water.

[0038] The foam drainage agent of the present invention has excellent foaming property at high gas flow rate, so that it has excellent foam drainage performance when applied in the gas transmission pipeline, and can ensure the stable operation of the gas transmission pipeline. At the same time, the foam drainage agent has weak thermal stability and is easily hydrolyzed and inactivated under acidic conditions. Therefore, the foam drainage agent is inactivated after draining to the natural gas terminal station, realizing defoaming and gas-liquid separation.

[0039] In the present invention, the key active components of the foam drainage agent are fatty acid ester polyethers, fatty acid ester polyether sulfates, and sulfosuccinates. Those skilled in the art know that for considerations such as facilitating transportation, storage, or on-site use, various supply forms can be adopted, such as a solvent-free solid form, a solvent-containing solid form, a solvent-containing paste form, or a solution form; the solution form includes a form in which a concentrated solution is prepared with a solution and a form of a treatment agent directly prepared at the concentration required for on-site foam drainage.

[0040] In the present invention, there is no special limitation on the content of the surfactant composition in the foam drainage agent. For the convenience of transportation, storage, or on-site use, the foam drainage agent can have a high concentration of the surfactant composition and can be diluted as needed during use; according to a preferred embodiment of the present invention, based on the total weight of the foam drainage agent, the content of the surfactant composition is 0.01 - 60 wt%, and the content of water is 40 - 99.99 wt%.

[0041] According to a preferred embodiment of the present invention, the foam volume of the foam drainage agent is greater than 300 mL, which is beneficial for liquid and sand carrying and removing pipeline liquid accumulation.

[0042] According to a preferred embodiment of the present invention, the liquid carrying capacity of the foam of the foam drainage agent at 15 min is ≥ 70%, which is beneficial for liquid and sand carrying and removing pipeline liquid accumulation.

[0043] According to a preferred embodiment of the present invention, after aging for 48 h at 50 °C and pH = 5, the foam volume of the foam drainage agent is less than 200 mL, and the liquid carrying capacity of the foam at 15 min is ≤ 30%.

[0044] According to a preferred embodiment of the present invention, the density of the foam formed by the foam drainage agent is 0.05 - 0.2 g / cm 3 , which is beneficial for liquid and sand carrying and removing pipeline liquid accumulation.

[0045] The foam drainage agent composition of the present invention has good compatibility and can also contain other commonly used treatment agents in the art for combined use. This is not elaborated herein.

[0046] In the present invention, there is no special limitation on the preparation process of the foam drainage agent, as long as the surfactant composition and water are mixed evenly.

[0047] The third aspect of the present invention provides an application of the foam drainage agent described in the present invention in removing liquid accumulation in pipelines.

[0048] According to a preferred embodiment of the present invention, the pipeline is an external transmission pipeline of an acid gas well.

[0049] The fourth aspect of the present invention provides a method for removing liquid accumulation according to the present invention. The method includes: injecting the foam drainage agent according to the present invention into a pipeline to form foam and remove the liquid accumulation in the pipeline.

[0050] The foam drainage agent according to the present invention has excellent foaming property. After being injected into the pipeline, under the action of high gas flow rate gas in the pipeline, it forms foam, carries liquid and sand, thereby removing the liquid accumulation in the pipeline.

[0051] In the present invention, there are no special limitations on the conditions for injecting the foam drainage agent. According to a preferred embodiment of the present invention, when injecting the foam drainage agent, the pressure in the pipe is not lower than 0.2 MPa.

[0052] In the present invention, the range of the injection amount of the foam drainage agent is relatively wide. According to a preferred embodiment of the present invention, the injection amount of the foam drainage agent makes the content of the surfactant composition be 0.05 wt% - 0.3 wt% of the liquid holdup in the pipeline.

[0053] To further understand the present invention, the preferred embodiments of the present invention will be described below in conjunction with examples. However, it should be understood that these descriptions are only for further explaining the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0054] In the following examples, the fatty acid ester polyether was purchased from Nantong Jiuze Chemical Co., Ltd.

[0055] The fatty acid ester polyether sulfate was provided by Sasol and Taiyuan Institute of Chemical Industry.

[0056] In the following examples, the water used was simulated water with a salinity of 30000 mg / L.

[0057] Example 1

[0058] At normal temperature and pressure, fatty acid ester polyether, fatty acid ester polyether sulfate and sodium succinate sulfonate were weighed and prepared into a 0.1 wt% aqueous solution according to a molar ratio of 1:10:5 to obtain the foam drainage agent combined solution F1.

[0059] Example 2

[0060] At normal temperature and pressure, fatty acid ester polyether, fatty acid ester polyether sulfate and sodium succinate sulfonate were weighed and prepared into a 0.1 wt% aqueous solution according to a molar ratio of 1:1:1 to obtain the foam drainage agent combined solution F2.

[0061] Example 3

[0062] At normal temperature and pressure, fatty acid ester polyether, fatty acid ester polyether sulfate and sodium succinate sulfonate were weighed and prepared into a 0.1 wt% aqueous solution according to a molar ratio of 1:0.1:1 to obtain the foam drainage agent combined solution F3.

[0063] Example 4

[0064] At normal temperature and pressure, weigh fatty acid ester polyether, fatty acid ester polyether sulfate, and sodium sulfosuccinate, and prepare an aqueous solution of 0.1 wt% according to a molar ratio of 1:1:0.1 to obtain the foam drainage agent combination liquid F4.

[0065] Example 5

[0066] At normal temperature and pressure, weigh fatty acid ester polyether, fatty acid ester polyether sulfate, and sodium sulfosuccinate, and prepare an aqueous solution of 0.3 wt% according to a molar ratio of 1:1:1 to obtain the foam drainage agent combination liquid F5.

[0067] Example 6

[0068] At normal temperature and pressure, weigh fatty acid ester polyether, fatty acid ester polyether sulfate, and sodium sulfosuccinate, and prepare an aqueous solution of 0.05 wt% according to a molar ratio of 1:1:1 to obtain the foam drainage agent combination liquid F6.

[0069] Example 7

[0070] At normal temperature and pressure, weigh fatty acid ester polyether, fatty acid ester polyether sulfate, and sodium sulfosuccinate, and prepare an aqueous solution of 0.1 wt% according to a molar ratio of 1:1:1 to obtain the foam drainage agent combination liquid F7.

[0071] Table 1 shows the composition component structures in Examples 1-7. The fatty acid ester polyether is as shown in formula (1), where R 1 , m, and n are shown in Table 1; the fatty acid ester polyether sulfate is as shown in formula (2), where R 2 , p, and q are shown in Table 1.

[0072] Number <![CDATA[R 1 > m n <![CDATA[R 2 > p q M Example 1 <![CDATA[C 12 H 25 > 0 5 <![CDATA[C 16 H 33 > 0 5 Na Example 2 <![CDATA[C 16 H 33 > 0 20 <![CDATA[C 18 H 35 > 0 10 <![CDATA[NH 4 > Example 3 <![CDATA[C 18 H 33 > 1 15 <![CDATA[C 12 H 25 > 1 2 Na Example 4 <![CDATA[C 10 H 21 > 2 15 <![CDATA[C 12 H 25 > 7 7 Na Example 5 <![CDATA[C 12 H 25 > 7 15 <![CDATA[C 12 H 25 > 7 7 Na Example 6 <![CDATA[C 12 H 25 > 7 15 <![CDATA[C 12 H 25 > 7 7 Na Example 7 <![CDATA[C 12 H 25 > 7 15 <![CDATA[C 10 H 21 > 0 3 Na

[0073] Example 8

[0074] According to the method of Example 7, the difference is that it contains the fatty acid ester polyethers shown in formula (1-1) and formula (1-2), specifically:

[0075] Formula (1-1): In formula (1), R 1 is C 12 H 25 , m = 7, n = 15;

[0076] Formula (1-2): In formula (1), R 1 is C 10 H 21 , m = 1, n = 10;

[0077] The molar ratio of the fatty acid ester polyether shown in formula (1-1), the fatty acid ester polyether shown in formula (1-2), fatty acid ester polyether sulfate, and sodium sulfosuccinate is 0.5:0.5:1:1; the other conditions are the same as in Example 7, and the foam drainage agent combined solution F8 is obtained.

[0078] Example 9

[0079] According to the method of Example 5, the difference is that it contains sodium fatty acid ester polyether sulfate shown in formula (2-1) and formula (2-2), specifically:

[0080] Formula (2-1): In formula (2), R 2 is C 12 H 25 , p = 7, q = 7;

[0081] Formula (2-2): In formula (2), R 2 is C 10 H 21 , p = 5, q = 8;

[0082] The molar ratio of the fatty acid ester polyether, sodium fatty acid ester polyether sulfate shown in formula (2-1), sodium fatty acid ester polyether sulfate shown in formula (2-2), and sodium sulfosuccinate is 1:0.8:0.2:1; the other conditions are the same as in Example 5, and the foam drainage agent combined solution F9 is obtained.

[0083] Comparative Example 1

[0084] According to the method of Example 6, the difference is that no fatty acid ester polyether is added, and the other conditions are the same as in Example 6, and the foam drainage agent combined solution D1 is obtained.

[0085] Comparative Example 2

[0086] According to the method of Example 6, the difference is that no fatty acid ester polyether sulfate is added, and the other conditions are the same as in Example 6, and the foam drainage agent combined solution D2 is obtained.

[0087] Comparative Example 3

[0088] According to the method of Example 6, the difference is that no sodium sulfosuccinate is added, and the other conditions are the same as in Example 6, and the foam drainage agent combined solution D3 is obtained.

[0089] Foaming capacity test: Using a 2152 Ross foam meter, put 450 mL of the foaming agent solutions (F1 - F9) prepared in Examples 1 - 9 and the solutions D1 - D3 prepared in Comparative Examples 1 - 3 into the separatory funnel supporting the Ross foam meter, and place 50 mL of the solution in the jacketed graduated cylinder. Let 450 mL of the foaming agent solution fall into the jacketed graduated cylinder from the upper part by gravity to generate foam. Record the foam volume after all the liquid has fallen completely. The test temperature is 50 °C. The results are shown in Table 2.

[0090] Table 2 Foaming amount, liquid-carrying rate and foam density of the aqueous solutions of the compositions in Examples 1-9 and Comparative Examples 1-3

[0091]

[0092] Test of liquid-carrying amount of foam: At 50 °C and a back pressure of 1 MPa, nitrogen gas at 4.2 m 3 / h was continuously introduced into the foaming agent solutions (F1-F9) prepared in Examples 1-9 above, the solutions D1-D3 prepared in Comparative Examples 1-3, the mass of the aqueous solution was 200 g, the blowing time was 15 min. After blowing, the mass of the carried-out liquid was recorded, and the liquid-carrying rate (the ratio of the mass of the carried-out liquid after blowing to the mass of the solution before blowing) was calculated. The results are shown in Table 2.

[0093] Test of foam density: The conductivity of the fluid carried in the above liquid-carrying amount test was measured by the conductivity method. The water content Φ in the foam was calculated by the following formula 1, and the foam density ρ was calculated by formula 2 f , and the results are shown in Table 2.

[0094] Φ = 3κ - 2.5×κ 3 / 4 + 0.5κ 2 Formula 1

[0095] Φ is the water content in the foam, and κ is the ratio of the foam conductivity to the aqueous solution conductivity

[0096] ρ f = ρ l Φ + ρ g (1 - Φ) Formula 2

[0097] ρ l is the liquid density, which is 1 g / cm 3 , ρ g is the gas density, which is 0.012 g / cm 3 .

[0098] The foaming agent solutions (F1-F9, D1-D3) prepared in Examples 1-9 and Comparative Examples 1-3 were charged with carbon dioxide gas, the pH was adjusted to 5, then sealed, placed in an oven at 50 °C for 48 h and then taken out. Then, the foaming amount and liquid-carrying rate were tested by the above method. The results are shown in Table 3.

[0099] Table 3 Foaming amount and liquid-carrying rate of the aqueous solutions of the compositions in Examples 1-9 and Comparative Examples 1-3 after aging.

[0100]

[0101]

[0102] As can be seen from the results in Table 2 and Table 3, the foam drainage agent of the present invention has excellent foam drainage performance, can stably drain liquid within 2 hours of aging, and the foaming volume and liquid-carrying rate of the foam drainage agent are greatly reduced after 48 hours of aging, and the foam drainage agent fails, realizing defoaming and gas-liquid separation.

[0103] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A surfactant composition, characterized in that, the composition comprises: fatty acid ester polyether, fatty acid ester polyether sulfate, and sulfosuccinate.

2. The surfactant composition according to claim 1, wherein, the molar ratio of fatty acid ester polyether, fatty acid ester polyether sulfate, and sulfosuccinate is 1:0.1 - 10:0.1 - 5.

3. The surfactant composition according to claim 1 or 2, wherein, the structural formula of the fatty acid ester polyether is as shown in formula (1); In formula (1), R 1 is a saturated or unsaturated fatty group having 10 to 18 carbon atoms, m is a number from 0 to 7, and n is a number from 5 to 20; and / or the structural formula of the fatty acid ester polyether sulfate is as shown in formula (2); In formula (2), R 2 is a saturated or unsaturated fatty group having 10 to 18 carbon atoms, p is a number from 0 to 7, q is a number from 2 to 10, M + is any one of an alkali metal ion or an ammonium ion; and / or the sulfosuccinate is at least one of an alkali metal salt, an alkaline earth metal salt, and an ammonium salt of sulfosuccinic acid. Preferably, the sulfosuccinate is sodium sulfosuccinate.

4. An anti - foam agent, characterized in that, it comprises the surfactant composition according to any one of claims 1 - 3 and water.

5. The anti - foam agent according to claim 4, wherein, the foaming volume of the anti - foam agent is greater than 300 mL; and / or the liquid - carrying capacity of the foam of the anti - foam agent at 15 min is ≥70%; Preferably, after aging at 50 °C and pH = 5 for 48 h, the foaming volume of the anti - foam agent is less than 200 mL, and the liquid - carrying capacity of the foam at 15 min is ≤30%.

6. The anti - foam agent according to claim 4 or 5, wherein, The density of the foam formed by the foam drainage agent is 0.05 - 0.2 g / cm 3 .

7. Use of the anti - foam agent according to any one of claims 4 - 6 in removing the accumulated liquid in a pipeline. Preferably, the pipeline is an external transmission pipeline of an acid gas well.

8. A method for removing accumulated liquid, characterized in that, the method comprises: injecting the anti - foam agent according to any one of claims 4 - 6 into the pipeline, and forming foam under the action of gas to remove the accumulated liquid in the pipeline.

9. The method according to claim 8, wherein, when injecting the anti - foam agent, the pressure in the pipe is not lower than 0.2 MPa.

10. The method according to claim 8 or 9, wherein, the addition amount of the anti - foam agent is such that the content of the surfactant is 0.05 wt% - 0.3 wt% of the pipeline liquid holdup.

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