Electrochemical treatment device and method for recycling barite

Abstract

The invention relates to an electrochemical treatment device and method for recycling barite, the electrochemical treatment device comprises a treatment tank and a control power supply arranged outside the treatment tank body, a plurality of groups of horizontally arranged polar plates are arranged in the treatment tank body, each group of polar plates is respectively connected with a positive electrode and a negative electrode of the control power supply, and the control power supply is connected with the control power supply. A plurality of groups of cathode plates and anode plates are formed, and the anode plates are positioned vertically above the cathode plates. According to the invention, the plurality of horizontally arranged polar plates are connected through the control power supply, so that the anode polar plates are arranged at the upper part and the cathode polar plates are arranged at the lower part, the separation of a low-density solid phase and barite is realized, and the recycling of the barite is facilitated; the electrochemical device is used for treating the drilling fluid, fine solid particles are removed, the density of the obtained recycled barite is larger than 4.2 g / cm < 3 >, the solid-phase particle size ranges from 10 micrometers to 40 micrometers, and the recycled barite is more suitable for preparing high-density drilling fluid.

Description

Technical Field

[0001] The invention belongs to the technical field of drilling fluid treatment, and in particular relates to an electrochemical treatment device and method for recovering barite. Background Art

[0002] Waste drilling fluid, especially those with a density greater than 1.6 g / cm 3 High-density waste drilling fluid, containing a large amount of weighting agents such as barite, is directly discarded without recycling, which not only causes the total amount of waste to increase, but also wastes important resources such as barite. At present, the technology of recovering barite from waste drilling fluid has been reported, such as a barite recovery and reuse system in petroleum drilling fluid disclosed in CN201610750U, which utilizes medium-speed and high-speed two-stage centrifuges to recover barite, can remove the low-density solid phase in the drilling fluid, and recover the barite and base slurry in the drilling fluid, but there is a high content of impurities in the low-density solid phase of the recovered barite, which limits its promotion and application. Such as CN104609455B, a method for recovering barite from waste drilling mud, recovering barite in the drilling fluid by adding a flotation agent, but there is a complex reagent system of the flotation machine, and the problem of complex process. For this reason, it is necessary to provide a method for recovering barite with a guaranteed quality and particle size gradation of recovered barite and a simple operating process. Summary of the invention

[0003] In view of the above problems, the present invention provides an electrochemical treatment device and method for recovering barite.

[0004] The first object of the present invention is to provide an electrochemical treatment device for recovering barite, the electrochemical treatment device comprising a treatment tank and a control power supply arranged outside the treatment tank body, a plurality of groups of horizontally arranged electrode plates are provided inside the treatment tank body, each group of the electrode plates is respectively connected to the positive and negative poles of the control power supply to form a plurality of groups of cathode plates and anode plates, and the anode plate is located vertically above the cathode plate.

[0005] Furthermore, the electrochemical treatment device further includes a first scraping mechanism, wherein the first scraping mechanism is connected to the anode plate and contacts the anode plate.

[0006] Furthermore, the electrochemical treatment device also includes a second scraping mechanism, which is arranged at the inner bottom of the treatment tank body and contacts the inner bottom wall of the treatment tank body.

[0007] Furthermore, a scraping brush is installed on the scraper plate of the second scraping mechanism.

[0008] Furthermore, an anti-corrosion layer is coated on the inner wall of the treatment tank body.

[0009] Furthermore, the processing tank body is made of carbon steel.

[0010] Furthermore, the electrode plate is a flat plate or a cylindrical plate.

[0011] Furthermore, the electrode plate is one of a non-metallic electrode plate or a metal electrode plate.

[0012] A second object of the present invention is to provide an electrochemical treatment method for recovering barite, the electrochemical treatment method comprising:

[0013] Arrange a plurality of groups of cathode plates and anode plates in parallel in a processing tank body, and ensure that the anode plates are located vertically above the cathode plates, and the distance between the cathode plates and the anode plates is the target distance;

[0014] The waste polysulfone drilling fluid is added into the treatment tank, and the voltage between several groups of cathode plates and anode plates connected to the control power supply is adjusted to the target voltage by controlling the power supply, and the sedimentation treatment is carried out under the electrochemical action, and then the slurry adsorbed by the cathode plate is collected and dehydrated and dried to obtain the product.

[0015] The solid content volume ratio of the waste polysulfone drilling fluid is 2% to 10%, and the pH value is 6 to 10.

[0016] Beneficial effects of the present invention:

[0017] The present invention realizes the separation of low-density solid phase and barite by means of a plurality of horizontally arranged plates and controlling the power supply connection so that the anode plate is arranged on the top and the cathode plate is arranged on the bottom, thereby facilitating the recycling of barite.

[0018] The present invention utilizes the electrochemical device to treat the drilling fluid, removes fine solid particles (including barite and low-density solid phase), and the density of the recovered barite is greater than 4.2g / cm 3 Above, the solid phase particle size is in the range of 10 to 40 μm, which is more suitable for preparing high-density drilling fluid;

[0019] The recovery method adopted by the invention is simple, easy to operate and easy to realize industrial production.

[0020] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic structural diagram of an electrochemical treatment device for recovering barite according to an embodiment of the present invention is shown;

[0023] Figure 2 A top view of an electrochemical treatment device for recovering barite according to an embodiment of the present invention is shown;

[0024] Figure 3 A schematic diagram of an electrochemical treatment method for recovering barite according to an embodiment of the present invention is shown;

[0025] Figure 4 A process flow chart for recovering barite from waste drilling fluid according to an embodiment of the present invention is shown;

[0026] In the figure:

[0027] 10. Processing tank body; 11. Anode plate; 12. Second scraping mechanism; 13. Cathode plate; 14. First scraping mechanism; 20. Control power supply. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figure 1 An electrochemical treatment device for recovering barite according to an embodiment of the present invention comprises a treatment cell body 10 and a control power supply 20 arranged outside the treatment cell body 10, wherein a plurality of groups of horizontally arranged electrode plates are arranged in the treatment cell body 10, and each group of the electrode plates is respectively connected to the positive and negative electrodes of the control power supply 20 to form a plurality of groups of cathode plates 13 and anode plates 11, wherein the anode plate 11 is located vertically above the cathode plate 13.

[0030] In the embodiment of the present invention, the electrode plate is stably disposed in the processing tank body 10 via a support frame. The support frame may be embedded in the inner wall of the processing tank body 10 or may be welded to the inner wall of the processing tank body 10 .

[0031] In the embodiment of the present invention, the processing tank body 10 is made of carbon steel, and the inner wall of the processing tank body 10 is coated with an anti-corrosion layer to improve the service life of the processing tank body 10.

[0032] In an embodiment of the present invention, the electrode plate is a flat plate or a cylindrical plate, and the electrode plate is one of a non-metallic electrode plate and a metal electrode plate, wherein the non-metallic electrode plate is such as a graphite electrode plate, and the metal electrode plate is such as a metal electrode plate such as aluminum, iron, steel, etc. coated or not coated with an insulating layer.

[0033] Installation of the electrochemical treatment device of this embodiment:

[0034] Several groups of plates are placed horizontally in the processing tank body 10, and each group of plates is connected to the control power supply 20 to form several groups of cathode plates 13 and anode plates 11, and the anode plates 11 are located vertically above the cathode plates 13, and the electrochemical treatment device is assembled.

[0035] In some embodiments of the present invention, in order to facilitate the cleaning of the mud on the anode plate, the electrochemical treatment device further includes a first scraping mechanism 14, the first scraping mechanism 14 is connected to the anode plate 11 and contacts the anode plate 11, and the axis of the first scraping mechanism 14 is perpendicular to the axis of the anode plate 11. Figure 2 As shown;

[0036] In the embodiment of the present invention, the first scraper mechanism 14 is connected to the anode plate through a connecting rod. The structure of the first scraper mechanism 14 is common knowledge in the technical field of the present invention, such as including a scraper plate and a transmission motor. The scraper plate is in contact with the anode plate. The scraper plate is connected to the output end of the transmission motor. The rotation of the transmission motor drives the scraper plate to rotate, thereby scraping off the mud on the anode plate and improving the collection efficiency of the mud on the anode plate.

[0037] In some embodiments of the present invention, the electrochemical treatment device further includes a second scraping mechanism 12, which is disposed at the inner bottom of the treatment tank body 10 and contacts the inner bottom wall of the treatment tank body 10. The structure of the second scraping mechanism 12 is common knowledge in the technical field of the present invention and will not be described in detail herein.

[0038] In addition, in order to prevent the second scraping mechanism 12 from scraping the coating layer on the inner wall of the processing tank body 10, a scraping brush is installed on the scraper of the second scraping mechanism 12, and the scraping brush is used to scrape off the mud on the inner wall of the processing tank body 10.

[0039] In some other embodiments of the present invention, there is provided an electrochemical treatment method for recovering barite, comprising:

[0040] Arrange a plurality of groups of cathode plates 13 and anode plates 11 in parallel in the processing tank 10, and ensure that the anode plates 11 are located vertically above the cathode plates 13, and the distance between the cathode plates 13 and the anode plates 11 is the target distance;

[0041] The waste polysulfone drilling fluid is added into the treatment tank body 10, and the voltage between the plurality of groups of cathode plates 13 and anode plates 11 connected to the control power supply 20 is adjusted to the target voltage by the control power supply 20, and the fluid is subjected to sedimentation treatment under the electrochemical action, and then the slurry adsorbed by the cathode plates 13 is collected, dehydrated and dried to obtain the fluid.

[0042] In an embodiment of the present invention, the solid content volume ratio of the waste polysulfonate drilling fluid is 2% to 10%, and the pH value is 6 to 10. The specific value of the solid content volume ratio of the waste polysulfonate drilling fluid can be 2%, 2.5%, 3%, 3.4%, 3.8%, 4%, 4.5%, 4.8%, 5%, 5.5%, 6%, 6.6%, 7%, 7.5%, 8%, 8.5%, 9%, 9.4%, 9.8% and 10%. Any one of the pH value of the waste polysulfonate drilling fluid can be 6, 6.5, 6.8, 7, 7.5, 7.6, 8, 8.6, 9, 9.4, 9.8, and 10.

[0043] The target distance is 20 cm to 30 cm, and a specific value of the target distance may be any one of 20 cm, 22 cm, 23 cm, 25 cm, 27 cm, 29 cm, and 30 cm.

[0044] The target voltage is 60V to 90V, and the specific value of the target voltage can be any one of 60V, 65V, 67V, 70V, 71V, 74V, 76V, 80V, 81V, 85V, 88V, and 90V;

[0045] The time of the sedimentation treatment is 15 minutes to 30 minutes, and the time of the sedimentation treatment under the electrochemical action is any one of 15 minutes, 17 minutes, 19 minutes, 20 minutes, 25 minutes, 27 minutes, and 30 minutes.

[0046] Example 1

[0047] Raw material preparation: waste polysulfone drilling fluid from an oil field, density 2.150g / cm 3, water content 40.30%, barite content 82.83%, diluting the above waste polysulfonate drilling fluid with water to a solid content volume ratio of 2%, and adding sulfuric acid to adjust the pH value to 6 to obtain the treated waste polysulfonate drilling fluid;

[0048] Equipment preparation: several groups of cathode plates 13 and anode plates are arranged in parallel in the processing tank 10, and the anode plate 11 is ensured to be located vertically above the cathode plate 13, and the distance between the cathode plate 13 and the anode plate is 20 cm, wherein the plates are graphite plates;

[0049] Electrochemical treatment: The waste polysulfone drilling fluid obtained in the above step is then added into the treatment tank body 10, and the voltage between the several groups of cathode plates 13 and anode plates 11 connected to the control power supply 20 is adjusted to 60V by the control power supply 20, and the sedimentation treatment is carried out under the electrochemical action, and the sedimentation treatment time is 30 minutes, and then the slurry adsorbed by the cathode plate 13 is collected and post-processed to obtain the recovered barite.

[0050] The dry density of the recovered barite was determined to be 4.22 g / cm 3 .

[0051] Example 2

[0052] Raw material preparation: waste polysulfone drilling fluid from an oil field, density 2.688g / cm 3 , water content 37.15%, barite content 74.27%, diluting the above waste polysulfonate drilling fluid with water to a solid content volume ratio of 5%, and adding sulfuric acid to adjust the pH value to 8.5 to obtain the treated waste polysulfonate drilling fluid;

[0053] Equipment preparation: several groups of cathode plates 13 and anode plates are arranged in parallel in the processing tank 10, and the anode plate 11 is ensured to be located vertically above the cathode plate 13, and the distance between the cathode plate 13 and the anode plate is 30 cm, wherein the plate is a cylindrical plate aluminum tube wrapped with polypropylene;

[0054] Electrochemical treatment: The waste polysulfone drilling fluid obtained in the above step is then added into the treatment tank body 10, and the voltage between the several groups of cathode plates 13 and anode plates 11 connected to the control power supply 20 is adjusted to 90V by the control power supply 20, and the sedimentation treatment is carried out under the electrochemical action, and the sedimentation treatment time is 15 minutes, and then the slurry adsorbed by the cathode plate 13 is collected and post-processed to obtain the recovered barite.

[0055] The dry density of the recovered barite was determined to be 4.26 g / cm 3 .

[0056] like Figure 3As shown, the principle of the electrochemical treatment method for recovering barite described in the embodiment of the present invention is:

[0057] High-density waste polysulfone drilling fluid is mainly composed of water, cuttings (low-density solid phase), barite and drilling fluid additives. Among them, low-density solid phase and fine barite less than 10um are the main factors affecting the recycling of drilling fluid and barite. In order to recycle high-quality barite, it is necessary to remove low-density solid phase and useless fine barite as much as possible. Since low-density solid phase and barite are both insoluble solid phase particles, the only optional separation is gravity sedimentation or centrifugal sedimentation. According to the Stocks sedimentation formula, the sedimentation rate is positively correlated with particle density and particle size. The greater the particle density, the coarser the particles, and the faster the sedimentation rate.

[0058] The low-density solid phase contained in high-density waste polysulfone drilling fluid is mainly quartz, feldspar, dolomite, and clay minerals, with a density usually between 2.4 and 2.6 g / cm 3 The density of barite is 4.2~4.5g / cm 3 The particle size of the mixture of low-density solid phase and barite is in the range of 1-100um, and the particle size is very small. Therefore, the conventional sedimentation separation velocity difference is very small, and it is difficult to obtain a good separation effect. For example, the barite separated by a medium-speed-high-speed two-stage centrifuge contains more than 40% low-density solid phase. In order to obtain an efficient separation effect, it is necessary to strengthen the sedimentation velocity difference between the low-density solid phase and barite, and separate and collect the two solid phases in time.

[0059] Research has found that low-density solid phase and barite are both negatively charged particles, and the Zeta potential of low-density solid phase is more negative, and it is easier to be adsorbed by the anode in the electrode field, and the finer the particles, the faster the adsorption speed. Therefore, in an embodiment of the present invention, in the electrochemical treatment device for recovering barite, several groups of cathode plates 13 and anode plates 11 are placed horizontally (horizontally horizontally distributed) in the treatment tank body 10, and the anode plate 11 is on top, and the cathode plate 13 is below. Low-density solid phase and fine barite are subjected to a large upward electrical adsorption in the electrode field, and the downward sedimentation is transformed into upward adsorption, and the lower the density and the finer the particle size, the greater the upward adsorption effect. The adsorption force of barite with a larger density and a coarser particle size is smaller, and a large sinking speed is still maintained; therefore, by adjusting the appropriate plate spacing and the appropriate voltage, sufficient residence time is ensured, and the low-density solid phase and barite can be separated, and timely collected separately, high-quality drilling fluid weighting barite can be obtained.

[0060] like Figure 4 As shown, a process flow for recovering barite from waste drilling fluid is provided, comprising:

[0061] Dilution and adjustment of waste drilling fluid: waste polysulfonate drilling fluid, water and pH adjuster are treated in a dilution and adjustment section equipment (such as a stirring tank) to obtain waste polysulfonate drilling fluid with a solid content volume ratio of 2% to 10% and a pH value of 6 to 10;

[0062] Electrochemical treatment: the waste polysulfone drilling fluid with a solid content volume ratio of 2% to 10% and a pH value of 6 to 10 in the dilution adjustment section equipment is transported to the electrochemical treatment device for recovering barite through a pipeline, and the distance between the anode plate 11 and the cathode plate 13 in the electrochemical treatment device for recovering barite is adjusted to 20 cm to 30 cm, and the voltage between the anode plate 11 and the cathode plate 13 is adjusted to 60V to 90V, and electrochemical treatment is performed, and the sedimentation treatment time under electrochemical action is 15min to 30min, and then a slurry containing barite is obtained from the cathode plate 13, and a slurry containing a low-density solid phase is obtained from the anode plate 11, that is, the separated slurry containing barite is obtained from the bottom of the electrochemical treatment device for recovering barite, and the separated slurry containing a low-density solid phase is obtained from the top of the electrochemical treatment device for collecting barite;

[0063] Dehydration and recovery: The slurry containing barite separated from the bottom of the electrochemical treatment device for recovering barite is subjected to dehydration treatment, wherein the obtained solid is the recovered barite, and the obtained liquid can be circulated to the dilution adjustment section equipment and used as water for diluting the waste polysulfone drilling fluid; the slurry containing low-density solid phase separated from the top of the electrochemical treatment device for collecting barite is subjected to dehydration treatment, wherein the obtained solid is the recovered low-density solid phase (i.e. Figure 4 The sludge marked in the figure) can be recycled to the dilution adjustment section equipment to be used as water for diluting the waste polysulfone drilling fluid.

[0064] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electrochemical treatment device for recovering barite, comprising a treatment tank (10) and a control power supply (20) arranged outside the treatment tank (10), characterized in that: The processing tank body (10) is provided with a plurality of groups of horizontally arranged electrode plates, each group of the electrode plates is respectively connected to the positive and negative electrodes of the control power supply (20), forming a plurality of groups of cathode electrode plates (13) and anode electrode plates (11), and the anode electrode plates (11) are located vertically above the cathode electrode plates (13).

2. An electrochemical treatment device for recovering barite according to claim 1, characterized in that: It also comprises a first scraping mechanism (14), wherein the first scraping mechanism (14) is connected to the anode plate (11) and contacts the anode plate (11).

3. An electrochemical treatment device for recovering barite according to claim 1, characterized in that: It also comprises a second scraping mechanism (12), wherein the second scraping mechanism (12) is arranged at the inner bottom of the processing tank body (10) and contacts the inner bottom wall of the processing tank body (10).

4. An electrochemical treatment device for recovering barite according to claim 3, characterized in that: A scraping brush is installed on the scraper plate of the second scraping mechanism (12).

5. An electrochemical treatment device for recovering barite according to claim 1, characterized in that: The inner wall of the treatment tank body (10) is coated with an anti-corrosion layer.

6. An electrochemical treatment device for recovering barite according to claim 1, characterized in that: The processing tank body (10) is made of carbon steel.

7. An electrochemical treatment device for recovering barite according to claim 1, characterized in that: The electrode plate is a flat plate or a cylindrical plate.

8. An electrochemical treatment device for recovering barite according to claim 1, characterized in that: The electrode plate is one of a non-metallic electrode plate and a metal electrode plate.

9. An electrochemical treatment method for recovering barite, characterized in that: include: Arranging a plurality of groups of cathode plates (13) and anode plates (11) in parallel in a processing tank body (10), and ensuring that the anode plate (11) is located vertically above the cathode plate (13), and the distance between the cathode plate (13) and the anode plate (11) is a target distance; Waste polysulfone drilling fluid is added into a treatment tank (10), and the voltage between a plurality of groups of cathode plates (13) and anode plates (11) connected to the control power supply (20) is adjusted to a target voltage by a control power supply (20), and sedimentation treatment is performed under electrochemical action, and then the slurry adsorbed by the cathode plates (13) is collected, dehydrated, and dried to obtain the product.

10. An electrochemical treatment method for recovering barite according to claim 9, characterized in that: The solid content volume ratio of the waste polysulfone drilling fluid is 2% to 10%, and the pH value is 6 to 10.

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