A method and system for treating oil and gas produced water based on the hydrate method

Abstract

The application discloses a kind of based on hydrate method's oil and gas produced water treatment method and system, including the object molecule and nonionic surfactant that insoluble in water are added in proportion with salt-containing wastewater with heavy metal ions and mixed to obtain total solution containing nonionic surfactant, the total solution obtained is placed in suitable cage type hydrate formation environment, forms cage type hydrate mixed liquor, cage form hydrate mixed liquor is carried out solid-liquid separation, the cage type hydrate solid obtained is decomposed naturally, and the treated fresh water, the object molecule and nonionic surfactant that insoluble in water are obtained, and this two parts are separated and can be recycled, using the application can effectively achieve the purpose of oil and gas produced water salt, heavy metal ion removal and concentrated salt solution production, desalination efficiency is 70-86%, and the removal efficiency of heavy metal ions is 80-95%, and it is suitable for water treatment industry of various high-salinity wastewater.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of water treatment, and particularly relates to a method and system for treating oil and gas produced water based on a hydrate method. BACKGROUND

[0002] A large amount of oil and gas produced water is discharged in the production process of the petroleum industry, which contains not only a large amount of high-concentration inorganic salts and organic pollutants, but also a large amount of pretreatment chemicals and heavy metal ions. Direct discharge of the oil and gas produced water not only causes environmental pollution by allowing the pollutants to enter the soil and atmosphere, but also causes waste of resources. Some enterprises still cannot meet the national discharge standards after investing a large amount of cost in treating the produced water, and safe and economic and reasonable disposal of the oil and gas produced water has become a serious problem restricting the development of related industries. Therefore, efficient treatment of the organic matter and heavy metal ions in the oil and gas produced water and finally realizing recovery of the inorganic salts and utilization of the water resources have great significance for solving the problems of resource shortage and environmental pollution and industrial development.

[0003] Cage hydrate is a crystalline non-stoichiometric solid compound, which is formed by hydrogen bond interaction of water molecules under certain pressure and temperature conditions to form a cage structure and surround guest molecules, and other impurities are excluded from the hydrate structure. The cage hydrate technology can be used for desalination treatment of high-salinity wastewater such as seawater and oil and gas produced water. The existing desalination processes such as reverse osmosis and multi-stage flash evaporation have the disadvantages of high energy consumption and cost and complicated operation, and compared with the cage hydrate technology, the cage hydrate technology has the advantages of low cost, non-pollution of products and simple operation, and has great development prospects.

[0004] However, the preparation of the cage hydrate still has problems such as long hydrate induction time and slow generation kinetics. The traditional preparation system uses a high-pressure reaction kettle, and the stirring mode has low efficiency and high energy consumption. The solid-liquid separation of the hydrate slurry and the concentrated liquid and the separation of the salt water in the gap between the hydrate and its crystal are still under exploration, and no systematic separation process has been formed, so that the desalination rate and the pure water yield of the system cannot be effectively improved. In addition, the recycling of the hydrate guest molecules and the non-ionic surfactant in the system is also an important factor for reducing the cost of the cage hydrate technology. SUMMARY

[0005] Therefore, the application provides a method and system for treating oil and gas produced water based on a hydrate method, which can effectively reduce the nucleation time of the hydrate system, improve the reaction rate, strengthen the separation effect, realize recycling, reduce energy consumption, and provide a guiding role for subsequent application of the cage hydrate technology in the removal and purification of high-salinity wastewater such as seawater and produced water.

[0006] The technical scheme is as follows, and one of the purposes of the application is achieved as follows:

[0007] A hydrate method-based oil and gas produced water treatment method, the key of which comprises the following steps:

[0008] S1, preparing a non-ionic surfactant-containing solution:

[0009] The water-insoluble guest molecules and non-ionic surfactants are added into the salt-containing wastewater with heavy metal ions in proportion to obtain a total non-ionic surfactant-containing solution, wherein the mass of the guest molecules is 7wt% to 21wt% of the total solution, and the mass of the non-ionic surfactants is 0.1wt% to 3wt% of the total solution;

[0010] S2, crystal nucleation and growth:

[0011] The total solution obtained in step S1 is placed in an environment suitable for the formation of clathrate hydrates, and the guest molecules combine with water molecules under the action of the non-ionic surfactants to form a clathrate hydrate mixture;

[0012] S3, solid-liquid separation:

[0013] The clathrate hydrate mixture obtained in step S2 is subjected to solid-liquid separation to obtain clathrate hydrate solids and a concentrated salt solution;

[0014] S4, recycling:

[0015] The clathrate hydrate solids obtained in step S3 are naturally decomposed to obtain treated fresh water, water-insoluble guest molecules and non-ionic surfactants, and the fresh water, hydrate guest molecules and non-ionic surfactants are separated for recycling.

[0016] The above technical solution is adopted,

[0017] The non-ionic surfactants reduce the surface tension, promote the contact between the guest molecules and the solution, enhance the ability of hydrate nucleation and growth, and enable the water molecules to fully contact the guest molecules at normal pressure, which is conducive to improving the hydrate speed. The guest molecules and non-ionic surfactants are not soluble in water, and can be recycled and reused, which can quickly and efficiently prepare hydrates.

[0018] As a preferred:

[0019] The above-mentioned non-ionic surfactants are Span20 or Span80.

[0020] The above-mentioned guest molecules are cyclopentane or cyclohexane.

[0021] The above-mentioned environment suitable for the formation of clathrate hydrates has a temperature of 5℃ to -10℃, a stirring speed of 300 to 800rpm, and a stirring time of 60 to 90min.

[0022] The solid-liquid separation in step S3 is one of vacuum filtration, centrifugal separation or a combination of both.

[0023] The centrifugal separation is performed at a temperature of 0-10 DEG C, a centrifugal speed of 2000-5000 rpm and a centrifugal time of 3-10 minutes.

[0024] The salt concentration of the salt-containing wastewater is not more than 16 wt%.

[0025] The separation of fresh water, guest molecules and non-ionic surfactants in step S4 is performed by layering and pipetting to separate the fresh water and the water-insoluble part.

[0026] The second object of the present application is achieved as follows:

[0027] A system suitable for an oil and gas produced water treatment method based on the hydrate method, which is characterized in that it comprises a normal pressure reaction module, a separation and recovery module and a data processing module arranged in sequence.

[0028] The normal pressure reaction module mainly comprises a constant temperature water bath box, a thermocouple inserted into the constant temperature water bath box, and a magnetic stirrer arranged in the constant temperature water bath box.

[0029] The separation and recovery module comprises a vacuum pump, a conical flask connected to the vacuum pump through a hose, a Buchner funnel placed on the conical flask, a refrigerated centrifuge and a storage tank.

[0030] The data processing module comprises a conductivity meter connected with a temperature sensor and an electrode sensor.

[0031] In the above technical solution, the normal pressure reaction module provides a place for the nucleation and growth of hydrate crystals, the separation and recovery module is used for the solid-liquid separation of hydrates and solution, and the separation and recovery of fresh water and guest molecules and non-ionic surfactants after treatment, and the data processing module is used for measuring and recording the data changes of the salt concentration of the solution.

[0032] Further,

[0033] The storage tank is provided with one liquid outlet at the top and one liquid outlet at the bottom.

[0034] Compared with the prior art, the present application has the beneficial effects that: the present application utilizes the surface tension reduction effect of non-ionic surfactant to make water molecules and guest molecules fully contact under normal pressure, and at the same time, the heat and mass transfer in the crystal nucleation and growth process is enhanced through stirring, so that hydrates are quickly and efficiently generated; the use of vacuum pump filtration for hydrate rough treatment, combined with centrifugation of a refrigerated centrifuge for efficient separation, can realize better separation effect of hydrate slurry and concentrated liquid, and salt water in the interstitial space between hydrates and crystals, and improve the desalination efficiency and pure water rate; the use of the characteristics that the guest molecules and non-ionic surfactant are not soluble with water realizes the recycling of the guest molecules and non-ionic surfactant, and can quickly and efficiently repeatedly prepare hydrates.

[0035] The present application can effectively achieve the purposes of oil and gas produced water salt and heavy metal ion removal and concentrated salt solution production, with the desalination efficiency being up to 86%, the removal efficiency of heavy metal ions being up to 95%, simple operation, strong economy, high efficiency, and being suitable for water treatment industries of various high-salinity wastewater, and having a good guiding effect on the development of hydrate technology.

[0036] In addition to nickel and chromium, the heavy metal ions in the method are also suitable for Cu, Zn, Li, Mn, As, Pb, Cd and the like. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 It is a system schematic diagram of Example 1.

[0038] Figure 2 It is a material diagram when the system of Example 1 is used. DETAILED DESCRIPTION

[0039] The present application will be further described in detail below with reference to the accompanying drawings.

[0040] Example 1, refer to Figure 1 The system of the oil and gas produced water treatment method based on the hydrate method shown in the drawing mainly comprises a constant-temperature water bath box 1, a magnetic stirrer, a stirring speed and time control area, a temperature control area, an upper cover provided at the top of the constant-temperature water bath box 1, a thermocouple 2 inserted into the inside of the water bath box 1, and a separation and recovery module and a data acquisition module arranged in sequence.

[0041] The separation and recovery module mainly comprises a vacuum pump 3, a conical flask 4, a Buchner funnel 5, a refrigerated centrifuge 6 and a storage tank 7. The vacuum pump 3 is provided with two air suction heads at the upper end, which are connected to the conical flask 4 through hoses, and the Buchner funnel 5 is placed on the conical flask 4. The centrifuge 6 is provided with an upper cover, and is provided with a temperature control area, a rotation speed and time control area outside, and is provided with a clamping device and a centrifuge tube 6a inside. The storage tank 7 is provided with an outlet 7b and 7a at the upper and lower parts respectively.

[0042] The data processing module mainly comprises an electric conductivity meter 8, a temperature sensor 9 and an electrode sensor 10. The electric conductivity meter 8 is provided with a function control area at the top, and is connected with the temperature sensor 9 and the electrode sensor 10 outside.

[0043] The use method of the oil and gas produced water treatment system based on the hydrate method according to the embodiment is as follows:

[0044] After the water bath circulation of the constant temperature water bath box 1 is started, the thermocouple 2 is inserted, the temperature is adjusted and kept at the set value (5℃ to -10℃), and then the feeding is prepared;

[0045] The object molecules, the non-ionic surfactant and the salt-containing wastewater with heavy metal ions are put into the constant temperature water bath box 1 at a set proportion, and are adjusted to a set rotation speed (300-800rpm) and time length (60-90min), and the magnetic stirring is started. The object molecules, the non-ionic surfactant and the salt-containing wastewater with heavy metal ions are quickly reacted to form a clathrate hydrate mixed solution, so that the normal pressure quick preparation of the hydrate is realized.

[0046] The vacuum pump 3 is started, and the clathrate hydrate mixed solution after the reaction is transferred to the Buchner funnel 5 for vacuum filtration. The concentrated solution enters the conical flask 4, and the hydrate solid remains on the Buchner funnel 5.

[0047] The refrigerated centrifuge 6 is started, the temperature is adjusted and kept at the set value (0℃ to -10℃), the hydrate solid is put into the centrifuge tube 6a inside, the rotation speed (2000-5000rpm) and time length (3-10min) are adjusted, and the centrifugation is started.

[0048] The clathrate hydrate solid after the centrifugation is transferred to the storage tank 7, and is left to decompose naturally. The object molecules and the non-ionic surfactant are separated from the fresh water, and are transferred from the 7a outlet for recycling. The treated fresh water is recycled through the 7b outlet, so that the efficient separation of the hydrate slurry is realized.

[0049] The temperature sensor 9 and the electrode sensor 10 connected to the electric conductivity meter 8 of the data processing module are respectively put into the concentrated solution and the fresh water obtained by the separation, and the electric conductivity is measured to determine the desalination rate and the pure water rate of the system.

[0050] The vacuum filtration and centrifugal separation in the separation and recovery module can be used only one or both, and the combination of both is recommended.

[0051] Figure 2 For the material change chart when using the combined separation and recovery method, wherein a is the generated cage-shaped hydrate mixed solution, b is the hydrate solid left in the Buchner funnel 5 after filtration, c is the physical chart after further centrifugal separation of the hydrate solid after filtration, d is the physical chart after natural decomposition of the cage-shaped hydrate solid, and the layering can be seen in the chart.

[0052] The application provides a kind of oil and gas produced water treatment method based on hydrate method, wherein the hydrate guest molecule is preferably water-immiscible organic guest molecule, and cyclopentane and cyclohexane, which can generate cage-shaped hydrate at normal pressure, are selected, and the method provided by the application is described below through specific examples, and the details of the medicines used are as shown in Table 1:

[0053] Table 1 Details of Experimental Medicine

[0054]

[0055] Example 2, a kind of oil and gas produced water treatment method based on hydrate method: take the salt-containing wastewater containing heavy metal ions, wherein the concentration of NaCl is 5wt%, the concentration of nickel sulfate is 1.5mg / L, and the concentration of chromium chloride is 1mg / L, 14wt% cyclopentane and 0.5wt% non-ionic surfactant Span20 are added to the salt-containing wastewater, a total solution containing non-ionic surfactant is obtained, the total solution is placed in a constant temperature water bath with a magnetic stirrer, and cage-shaped hydrate is quickly formed after sufficient stirring for 60min, the speed of the magnetic stirrer is 400rpm, and the water bath temperature is-2℃. The obtained cage-shaped hydrate mixed solution is vacuum filtered to obtain a concentrated salt solution and a coarsely treated cage-shaped hydrate solid, and the coarsely treated cage-shaped hydrate solid is centrifuged at a temperature of-5℃ and a speed of 5000rpm for 10min to obtain pure cage-shaped hydrate solid and a concentrated salt solution.

[0056] The pure cage-shaped hydrate solid is naturally decomposed to obtain cyclopentane and Span20 in a layered state, fresh water, and the recovered cyclopentane and Span20 are used for recycling, and the concentrated salt solution after reaction can be used as raw material for extracting high-value-added salt.

[0057] The conductivity of the salt solution before and after reaction is measured by using a conductivity meter, and the concentration of heavy metal ions in the solution before and after reaction is measured by using an Agilent 4210 microwave plasma emission spectrometer, and the desalination efficiency is 86%, and the removal efficiency of heavy metal ions is 91% for nickel and 90% for chromium.

[0058] Example 3, a hydrate method-based oil and gas produced water treatment method: take salt-containing wastewater with heavy metal ions, wherein the concentration of NaCl is 10wt%, the concentration of nickel sulfate is 1.5mg / L, and the concentration of chromium chloride is 1mg / L, add 21wt% of cyclohexane and 3wt% of non-ionic surfactant Span20 to the salt-containing wastewater to obtain a total solution containing non-ionic surfactant, put the total solution into a constant-temperature water bath with a magnetic stirrer, fully stir for 90min to quickly form a cage-shaped hydrate, the stirring speed of the magnetic stirrer is 300rpm, and the water bath temperature is -4℃, vacuum suction filter the obtained cage-shaped hydrate mixture to obtain a concentrated salt solution and a coarsely treated cage-shaped hydrate solid, and centrifuge the coarsely treated cage-shaped hydrate solid at a temperature of 0℃ and a speed of 2000rpm for 3min to obtain pure cage-shaped hydrate solid and a concentrated salt solution.

[0059] Let the pure cage-shaped hydrate solid stand and naturally decompose to obtain cyclopentane and Span20 in a layered state and fresh water, recycle the cyclohexane and Span20 for cyclic use, and the concentrated salt solution after the reaction can be used as raw material for extracting high-value-added salt.

[0060] Use a conductivity meter to measure the conductivity of the salt solution before and after the reaction, and use an Agilent 4210 microwave plasma emission spectrometer to measure the concentration of heavy metal ions in the solution before and after the reaction, and the desalination efficiency is 83%, and the removal efficiency of heavy metal ions is 90% for nickel and 95% for chromium.

[0061] Example 4, a hydrate method-based oil and gas produced water treatment method: take salt-containing wastewater with heavy metal ions, wherein the concentration of NaCl is 3.5wt%, the concentration of nickel sulfate is 1.5mg / L, and the concentration of copper sulfate is 1mg / L, add 7wt% of cyclohexane and 0.1wt% of non-ionic surfactant Span80 to the salt-containing wastewater to obtain a total solution containing non-ionic surfactant, put the total solution into a constant-temperature water bath with a magnetic stirrer, fully stir for 80min to quickly form a cage-shaped hydrate, the stirring speed of the magnetic stirrer is 800rpm, and the water bath temperature is -1℃, vacuum suction filter the obtained cage-shaped hydrate mixture to obtain a concentrated salt solution and a coarsely treated cage-shaped hydrate solid, and centrifuge the coarsely treated cage-shaped hydrate solid at a temperature of -10℃ and a speed of 3500rpm for 5min to obtain pure cage-shaped hydrate solid and a concentrated salt solution.

[0062] Let the pure cage-shaped hydrate solid stand and naturally decompose to obtain cyclopentane and Span80 in a layered state and fresh water, recycle the cyclohexane and Span80 for cyclic use, and the concentrated salt solution after the reaction can be used as raw material for extracting high-value-added salt.

[0063] The conductivity of the salt solution before and after the reaction was measured using a conductivity meter, and the concentration of heavy metal ions in the solution before and after the reaction was measured using an Agilent 4210 microwave plasma emission spectrometer. The desalination efficiency was 72%, and the removal efficiency of heavy metal ions was 82% for nickel and 84% for chromium.

[0064] Example 5: An oil and gas produced water treatment method based on the hydrate method: Take salt-containing wastewater with heavy metal ions, wherein the concentration of NaCl is 16wt%, the concentration of zinc chloride is 1.5mg / L, and the concentration of copper sulfate is 1mg / L. Add 10wt% of cyclopentane and 2.0wt% of non-ionic surfactant Span80 to the salt-containing wastewater, obtain a total solution containing non-ionic surfactant, and place the total solution in a constant temperature water bath with a magnetic stirrer for sufficient stirring for 90min to quickly form a cage-shaped hydrate. The speed of the magnetic stirrer is 500rpm, and the water bath temperature is -10℃. The obtained cage-shaped hydrate mixture is vacuum filtered to obtain a concentrated salt solution and a coarsely treated cage-shaped hydrate solid. The coarsely treated cage-shaped hydrate solid is then centrifuged at a temperature of -3℃ and a speed of 4200rpm for 6min to obtain pure cage-shaped hydrate solid and concentrated salt solution.

[0065] The pure cage-shaped hydrate solid is left to decompose naturally to obtain cyclopentane and Span80 in a layered state, and fresh water. The recovered cyclopentane and Span80 can be recycled for use, and the concentrated salt solution after the reaction can be used as raw material for extracting high-value-added salt.

[0066] The conductivity of the salt solution before and after the reaction was measured using a conductivity meter, and the concentration of heavy metal ions in the solution before and after the reaction was measured using an Agilent 4210 microwave plasma emission spectrometer. The desalination efficiency was 72%, and the removal efficiency of heavy metal ions was 82% for nickel and 84% for chromium.

[0067] Example 6: An oil and gas produced water treatment method based on the hydrate method: Take salt-containing wastewater with heavy metal ions, wherein the concentration of NaCl is 1wt%, the concentration of nickel sulfate is 1.5mg / L, and the concentration of chromium chloride is 1mg / L. Add 7wt% of cyclopentane and 0.5wt% of non-ionic surfactant Span80 to the salt-containing wastewater to obtain a total solution containing non-ionic surfactant. Place the total solution in a constant temperature water bath with a magnetic stirrer for sufficient stirring for 90min to quickly form a cage-shaped hydrate. The speed of the magnetic stirrer is 400rpm, and the water bath temperature is 4℃. The obtained cage-shaped hydrate mixture is vacuum filtered to obtain a concentrated salt solution and a coarsely treated cage-shaped hydrate solid. The coarsely treated cage-shaped hydrate solid is then centrifuged at a temperature of -5℃ and a speed of 5000rpm for 10min to obtain pure cage-shaped hydrate solid and concentrated salt solution.

[0068] The pure cage hydrate solid is left to decompose naturally to obtain cyclopentane and Span 80 in a layered state, and the cyclopentane and Span 80 are recovered for recycling, and the concentrated salt solution after the reaction can be used as raw material for extracting high value-added salt.

[0069] The conductivity of the salt solution before and after the reaction is measured by using a conductivity meter, and the concentration of heavy metal ions in the solution before and after the reaction is measured by using an Agilent 4210 microwave plasma emission spectrometer, and the desalination efficiency is 73%, and the removal efficiency of heavy metal ions is 84% for nickel and 82% for chromium.

[0070] Comparative Example 1:

[0071] The difference between the example 2 and the comparative example 1 is only that the solid-liquid separation method of vacuum filtration is used, and the method of centrifugation is not combined, and finally the desalination efficiency is 65%, and the removal efficiency of heavy metal ions is 79% for nickel and 76% for chromium, which is slightly lower than that of the example 2, but is also significantly higher than other traditional methods, and the nucleation time is less than 90 min.

[0072] Comparative Example 2:

[0073] The difference between the example 2 and the comparative example 2 is only that the solid-liquid separation method of centrifugation is used, and the method of vacuum filtration is not combined, and finally the desalination efficiency is 68%, and the removal efficiency of heavy metal ions is 83% for nickel and 78% for chromium, which is slightly lower than that of the example 2, but is also significantly higher than other traditional methods, and the nucleation time is less than 90 min.

[0074] Comparative Example 3:

[0075] The difference between the example 2 and the comparative example 3 is only that the non-ionic surfactant is not added as the nucleation promoter of the hydrate, and finally the desalination efficiency is 58%, and the removal efficiency of heavy metal ions is 75% for nickel and 70% for chromium, and the nucleation time is greatly increased, about 390 min.

[0076] Comparative Example 4 (SDS inhibition):

[0077] The difference between the example 2 and the comparative example 4 is only that the anionic surfactant SDS with a mass concentration of 0.5 wt% is added as the nucleation promoter of the hydrate, and finally the desalination efficiency is 45%, and the removal efficiency of heavy metal ions is 62% for nickel and 58% for chromium, and the growth time is greater than 390 min.

[0078] Comparative Example 5 (Span 60 inhibition):

[0079] The difference from Example 2 is that 0.5wt% nonionic surfactant Span 60 is added as a nucleation promoter for hydrate, and the final desalination efficiency is 42%, the removal efficiency of heavy metal ions is 58% for nickel and 54% for chromium, and the growth time is greater than 390 min.

[0080] Finally, it should be noted that the above description is only for the preferred embodiments of the present application, and those of ordinary skill in the art can make various similar modifications under the inspiration of the present application without departing from the purpose and scope of the present application. Such changes fall within the scope of the present application.

Claims

1. A method for treating oil and gas produced water based on the hydrate method, characterized in that... Includes the following steps: S1. Preparation of a solution containing a nonionic surfactant: Insoluble guest molecules and nonionic surfactants are added to saline wastewater containing heavy metal ions in a certain proportion to obtain a total solution containing nonionic surfactants. The mass of the guest molecules is 7 wt% to 21 wt% of the total solution mass, the mass of the nonionic surfactants is 0.1 wt% to 3 wt% of the total solution mass, and the salt concentration of the saline wastewater does not exceed 16 wt%. S2, Crystal nucleation and growth: The total solution obtained in step S1 is placed in a suitable environment for the formation of cage hydrates. Under the action of nonionic surfactants, guest molecules combine with water molecules to form a cage hydrate mixture. S3, Solid-liquid separation: The cage-shaped hydrate mixture obtained in step S2 is subjected to solid-liquid separation to obtain cage-shaped hydrate solid and concentrated salt solution; S4. Recycling: The cage-shaped hydrate solid obtained in step S3 is naturally decomposed to obtain treated fresh water, water-insoluble guest molecules and nonionic surfactants. The fresh water, guest molecules and nonionic surfactants can be separated and recycled. The nonionic surfactant is Span20 or Span80; The guest molecule is cyclopentane or cyclohexane; The suitable environment for the formation of cage-like hydrates is characterized by a temperature of 5℃ to -10℃, a stirring speed of 300 to 800 rpm, and a stirring time of 60 to 90 minutes.

2. The method for treating produced water based on the hydrate method according to claim 1, characterized in that: The solid-liquid separation described in step S3 is achieved by one or a combination of vacuum filtration, centrifugation, or both.

3. The method for treating produced water based on the hydrate method according to claim 2, characterized in that: The centrifugation temperature is 0℃ to -10℃, the centrifugation speed is 2000 to 5000 rpm, and the centrifugation time is 3 to 10 min.

4. A method for treating oil and gas produced water based on the hydrate method according to any one of claims 1-3, characterized in that: In step S4, the separation of fresh water, guest molecules, and nonionic surfactants refers to the separation of fresh water and the water-insoluble portion by a layered transfer method.

5. A system for treating oil and gas produced water based on the hydrate method as described in any one of claims 1-4, characterized in that: It includes an atmospheric pressure reaction module, a separation and recovery module, and a data processing module arranged sequentially. The atmospheric pressure reaction module includes a constant temperature water bath, a thermocouple inserted inside the constant temperature water bath, and a magnetic stirrer installed inside the constant temperature water bath. The separation and recovery module includes a vacuum pump connected to a conical flask via a hose, a Buchner funnel placed on the conical flask, a refrigerated centrifuge, and a storage tank. The data processing module includes a conductivity meter, which is connected to a temperature sensor and an electrode sensor.

6. The oil and gas produced water treatment system based on the hydrate method according to claim 5, characterized in that: The storage tank has a liquid outlet at both the top and bottom.

Images