Fracturing flow-back fluid treatment device based on electrochemical method

Abstract

The utility model relates to a fracturing flow-back fluid treatment device based on an electrochemical method, and relates to the technical field of sewage treatment in the petrochemical industry. The fracturing flow-back fluid treatment device comprises an electrochemical energized demulsification reaction tank, an electrochemical flocculation reaction tank and a mud-water separation tank, the outflow end of the electrochemical energizing demulsification reaction tank is connected with the inflow end of the electrochemical flocculation reaction tank, and the outflow end of the electrochemical flocculation reaction tank is connected with the inflow end of the mud-water separation tank. The fracturing flow-back fluid treatment device is short in treatment process flow, simple in operation management and low in treatment cost, and the operation cost is reduced by more than 50% compared with that of an existing treatment process under the same water quality condition.

Description

TECHNICAL FIELD

[0001] The utility model relates to a fracturing flowback fluid treatment device based on electrochemistry, relate to petrochemical industry sewage treatment technical field. BACKGROUND

[0002] Fracturing flowback fluid has high salt content, high organic matter content and complex composition, water quality changes with development process, and water quality of fracturing flowback fluid in different blocks is quite different.

[0003] The current treatment technology is: buffer → oil removal by sedimentation separation → filtration, the difference of each technology is that the oil removal by sedimentation separation adopts different ways, mainly including: gravity coagulation sedimentation oil removal process, pressure inclined plate tank closed oil removal process, cyclone oil removal process, pressure filtration technology, low-permeability oilfield fine water treatment technology and water quality modification treatment technology, etc. The existing oil removal process has the following shortcomings: (1) because the fracturing flowback fluid has high salt content and complex organic matter composition, the amount of demulsifying agent added is large, the cost is high, and the treatment cost per ton of water is 50-150 yuan / ton of water; (2) the water quality of different development processes and different blocks is quite different, so the types and dosages of agents need to be adjusted constantly, the actual workload is large, and the operation and running difficulty is high; (3) because the amount of agent added is large, the amount of sludge is large, the sludge-water separation difficulty is high, resulting in large size and high cost of sludge-water separation equipment, and high sludge disposal cost. SUMMARY

[0004] To solve the above technical problems, the purpose of the utility model is to provide a fracturing flowback fluid treatment device based on electrochemistry, which solves the problems of large amount of agent addition, large workload and high cost of the existing oil removal process, and has short process flow, simple operation and management, and low treatment cost.

[0005] The technical solution of the utility model for solving the above technical problems is as follows:

[0006] The purpose of the utility model is to provide a fracturing flowback fluid treatment device based on electrochemistry, which includes an electrochemical electrification demulsification reaction tank, an electrochemical flocculation reaction tank and a sludge-water separation tank.

[0007] The outflow end of the electrochemical electrification demulsification reaction tank is connected with the inflow end of the electrochemical flocculation reaction tank, and the outflow end of the electrochemical flocculation reaction tank is connected with the inflow end of the sludge-water separation tank.

[0008] The utility model discloses beneficial effect is: (1) the utility model discloses in electrochemistry is given electricity demulsification reaction pool, electrochemistry flocculation reaction pool adopts electrochemistry method to handle fracturing flowback fluid, can be flexible applicable to the huge difference of fracturing flowback fluid water quality, can adjust output current, voltage according to the different water quality, simple operation, (2) the utility model discloses adopts electrochemistry is given electricity demulsification reaction pool for demulsification and separate the oil in fracturing flowback fluid and obtain the fracturing flowback fluid after the oil is removed, again enter electrochemistry flocculation reaction pool for flocculation and remove the pollutant in the fracturing flowback fluid after the oil, obtain the electrocoagulation effluent, finally sludge separation tank is used for separating electrocoagulation effluent and obtains the standard supernatant and sludge.

[0009] Further, the electrochemistry is given electricity demulsification reaction pool includes water inlet pipe, first water inlet baffle, electrochemistry inert partial polar plate, first electrochemistry inert main polar plate, second electrochemistry inert main polar plate;

[0010] One end of the electrochemistry is given electricity demulsification reaction pool is provided with the water inlet pipe, and the inside of the electrochemistry is given electricity demulsification reaction pool is sequentially installed with the first water inlet baffle, the first electrochemistry inert main polar plate, the electrochemistry inert partial polar plate and the second electrochemistry inert main polar plate from the side close to the water inlet pipe.

[0011] The beneficial effect of the above further scheme is: using electrochemistry method demulsification in electrochemistry is given electricity demulsification reaction pool, after fracturing flowback fluid enters electrochemistry is given electricity demulsification reaction pool, the nanometer microbubble generated by electrochemical reaction destroys oil drop interface film, and the oil particles in emulsified state are given electricity by electric field and then move directionally and coagulate into large particles to realize demulsification, and the iron and aluminum cations generated by electrochemical reaction can further cooperate with demulsification and oil-water separation. The high salt content in fracturing flowback fluid plays a positive role in electrochemical treatment process, and the high salt content can enhance the conductivity of wastewater and reduce the energy consumption of electrochemical treatment.

[0012] Further, the top end of the partitioned side wall of the electrochemistry is given electricity demulsification reaction pool and the electrochemistry flocculation reaction pool is provided with a dregs tank, and the bottom end of the dregs tank is provided with a dregs discharge port; the top end of the inner side wall of the dregs tank is respectively provided with a first dregs scraper and a second dregs scraper.

[0013] Further, the electrochemistry is given electricity demulsification reaction pool is provided with a first separation plate and a second separation plate, the first separation plate and the second separation plate are inclined to the horizontal plane, and the lower edge of the first separation plate and the second separation plate is connected with the corresponding bottom wall of the electrochemistry is given electricity demulsification reaction pool, and the upper edge of the first separation plate and the second separation plate is connected with the corresponding inner side wall of the electrochemistry is given electricity demulsification reaction pool, and the bottom of the electrochemistry is given electricity demulsification reaction pool is provided with a first sludge discharge port.

[0014] Further, the electrochemical flocculation reaction tank comprises a second water inlet baffle, an electrochemical flocculation sub-polar plate, a first electrochemical flocculation main polar plate and a second electrochemical flocculation main polar plate.

[0015] The inside of the electrochemical flocculation reaction tank is sequentially provided with the second water inlet baffle, the first electrochemical flocculation main polar plate, the electrochemical flocculation sub-polar plate and the second electrochemical flocculation main polar plate from the side close to the electrochemical electrification demulsification reaction tank.

[0016] The beneficial effects of the above further scheme are that the mud-water separation device is small, the sludge yield is small, and the operation cost is low.

[0017] Further, the mud-water separation tank is provided with a fifth separation plate and a sixth separation plate, the fifth separation plate and the sixth separation plate are inclined to the horizontal plane, the lower edge of the fifth separation plate and the sixth separation plate is connected with the bottom of the mud-water separation tank, the upper edge of the fifth separation plate and the sixth separation plate is connected with the inner side wall of the mud-water separation tank, and the bottom of the mud-water separation tank is provided with a third sludge discharge port.

[0018] Further, the electrochemical flocculation reaction tank is provided with a third separation plate and a fourth separation plate, the third separation plate and the fourth separation plate are inclined to the horizontal plane, the lower edge of the third separation plate and the fourth separation plate is connected with the bottom of the electrochemical flocculation reaction tank, the upper edge of the third separation plate and the fourth separation plate is connected with the inner side wall of the electrochemical flocculation reaction tank, and the bottom of the electrochemical flocculation reaction tank is provided with a second sludge discharge port.

[0019] Further, the upper end of the inner side wall of the side close to the electrochemical flocculation reaction tank of the mud-water separation tank is provided with an electrochemical reaction effluent tank, and the inside of the electrochemical reaction effluent tank is provided with a stirrer.

[0020] Further, the lower part of the electrochemical electrification demulsification reaction tank and the electrochemical flocculation reaction tank is provided with a cleaning air pipe.

[0021] Further, the upper end of the side wall of the side away from the electrochemical flocculation reaction tank of the mud-water separation tank is provided with a sedimentation zone effluent tank, and the sedimentation zone effluent tank is connected with an effluent port. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a fracturing flowback fluid treatment device of the utility model.

[0023] In the drawings, the components represented by each reference numeral are listed as follows:

[0024] 1. Electrochemical electro-demulsification reaction tank; 101. First inlet baffle; 102. First electrochemical inert main electrode plate; 103. Electrochemical inert separating electrode plate; 104. Second electrochemical inert main electrode plate; 105. First sludge discharge port; 106. First separation plate; 107. Second separation plate; 2. Electrochemical flocculation reaction tank; 201. First electrochemical flocculation main electrode plate; 202. Electrochemical flocculation separating electrode plate; 203. Second electrochemical flocculation main electrode plate; 20 4. Second sludge discharge port; 205. Third separation plate; 206. Fourth separation plate; 207. Second water inlet baffle; 3. Sludge-water separation tank; 301. Third sludge discharge port; 302. Fifth separation plate; 306. Sixth separation plate; 4. Water inlet pipe; 5. Cleaning air duct; 6. First slag scraper; 7. Second slag scraper; 8. Scum tank; 9. Slag discharge port; 10. Electrochemical reaction outlet tank; 11. Agitator; 12. Sedimentation zone outlet tank; 13. Water outlet. Detailed Implementation

[0025] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0026] like Figure 1 As shown, the fracturing flowback fluid treatment device includes an electrochemical electrolytic demulsification reaction tank 1, an electrochemical flocculation reaction tank 2, and a mud-water separation tank 3;

[0027] The outflow end of the electrochemical electro-demulsification reaction tank 1 is connected to the inflow end of the electrochemical flocculation reaction tank 2, and the outflow end of the electrochemical flocculation reaction tank 2 is connected to the inflow end of the mud-water separation tank 3.

[0028] In some embodiments, the electrochemically charged demulsifying reaction cell 1 includes an inlet pipe 4, a first inlet baffle 101, an electrochemically inert electrode plate 103, a first electrochemically inert main electrode plate 102, and a second electrochemically inert main electrode plate 104.

[0029] An inlet pipe 4 is provided on the side wall of the electrochemical electro-electrodemulsification reaction tank 1. Inside the electrochemical electro-electrodemulsification reaction tank 1, from the side closest to the inlet pipe 4, a first inlet baffle 101, a first electrochemical inert main electrode plate 102, an electrochemical inert secondary electrode plate 103, and a second electrochemical inert main electrode plate 104 are installed in sequence.

[0030] As an optimization of the above embodiment, according to a fracturing flowback fluid treatment device based on electrochemical method, a scum trough 8 is provided at the top of the separating sidewall of the electrochemical electro-demulsification reaction tank 1 and the electrochemical flocculation reaction tank 2, and a scum discharge port 9 is provided at the bottom of the scum trough 8; a first scraper 6 and a second scraper 7 are respectively provided at the top of the inner sidewall of the scum trough 8.

[0031] In some other embodiments, the electrochemical electrifying demulsification reaction tank 1 is provided with a first separation plate 106 and a second separation plate 107, which are inclined to the horizontal plane, and the lower edges of the first separation plate 106 and the second separation plate 107 are connected with the corresponding bottom wall of the electrochemical electrifying demulsification reaction tank 1, and the upper edges of the first separation plate 106 and the second separation plate 107 are connected with the corresponding inner side wall of the electrochemical electrifying demulsification reaction tank 1, and the bottom of the electrochemical electrifying demulsification reaction tank 1 is provided with a first sludge discharge port 105.

[0032] In some other embodiments, the electrochemical flocculation reaction tank 2 comprises a second water inlet baffle 207, an electrochemical flocculation sub-pole plate 202, a first electrochemical flocculation main pole plate 201, and a second electrochemical flocculation main pole plate 203.

[0033] The inside of the electrochemical flocculation reaction tank 2 is sequentially provided with the second water inlet baffle 207, the first electrochemical flocculation main pole plate 201, the electrochemical flocculation sub-pole plate 202, and the second electrochemical flocculation main pole plate 203 from the side close to the electrochemical electrifying demulsification reaction tank 1.

[0034] In some other embodiments, the sludge-water separation tank 3 is provided with a fifth separation plate 302 and a sixth separation plate 303, which are inclined to the horizontal plane, and the lower edges of the fifth separation plate 302 and the sixth separation plate 303 are connected with the bottom of the sludge-water separation tank 3, and the upper edges of the fifth separation plate 302 and the sixth separation plate 303 are connected with the inner side wall of the sludge-water separation tank 3, and the bottom of the sludge-water separation tank 3 is provided with a third sludge discharge port 301.

[0035] In some other embodiments, the electrochemical flocculation reaction tank 2 is provided with a third separation plate 205 and a fourth separation plate 206, which are inclined to the horizontal plane, and the lower edges of the third separation plate 205 and the fourth separation plate 206 are connected with the bottom of the electrochemical flocculation reaction tank 2, and the upper edges of the third separation plate 205 and the fourth separation plate 206 are connected with the inner side wall of the electrochemical flocculation reaction tank 2, and the bottom of the electrochemical flocculation reaction tank 2 is provided with a second sludge discharge port 204.

[0036] In some other embodiments, the upper end of the side wall of the sludge-water separation tank 3 close to the electrochemical flocculation reaction tank 2 is provided with an electrochemical reaction water outlet tank 10, and the inside of the electrochemical reaction water outlet tank 10 is provided with a stirrer 11.

[0037] In some other embodiments, a cleaning air pipe 5 is installed at the lower part of the electrochemical electrifying demulsification reaction tank 1 and the electrochemical flocculation reaction tank 2.

[0038] In some other embodiments, the upper end of the side wall of the sludge-water separation tank 3 away from the electrochemical flocculation reaction tank 2 is provided with a precipitation zone water outlet tank 12, and the precipitation zone water outlet tank 12 is connected with the outside through a water outlet 13.

[0039] Preferably, the electrochemical flocculation reaction tank 2 adopts a ferrous plate as a consumption plate, and in the reactor, the iron of the anode is consumed to generate ferrous ions as a flocculant into the water through an electrolytic reaction, a flocculation reaction occurs and the pollutants in the water are adsorbed, meanwhile, the hydroxyl radicals generated by the electrolytic reaction have strong oxidizing properties and can oxidize the high molecular pollutants in the wastewater, and the electrolytic reaction also generates tiny bubbles to further remove the oil in the water. The mixed water with the iron flocculant enters the sludge-water separation area, and in a suitable pH value range, the iron hydroxide precipitate is formed to realize sludge-water separation.

[0040] In Figure 1 , the fracturing backflow liquid treatment device of the utility model works, first, the fracturing backflow liquid is transported to the electrochemical electricity-given demulsification reaction tank 1 through the water inlet pipe 4, the first electrochemical inert main plate 102 (graphite plate), the electrochemical inert sub-plate 103, and the second electrochemical inert main plate (ferrous plate) 104 are electrified, an electrochemical reaction occurs, the fracturing backflow liquid is demulsified, the nanoscale micro-bubbles generated by the electrochemical reaction destroy the oil droplet interface film, the oil particles in the emulsified state are given electricity and move directionally and coagulate into large particles to realize demulsification through the electric field, meanwhile, the iron and aluminum cations generated by the electrochemical reaction can further cooperate with demulsification and oil-water separation, most of the oil floats up, is scraped into the floating sludge tank 8 through the first slag scraper 6 and the second slag scraper 7, and is discharged through the slag discharge port 9, the remaining wastewater enters the electrochemical flocculation reaction tank 2 again, the first electrochemical flocculation main plate 201 (ferrous plate), the electrochemical flocculation sub-plate 202, and the second electrochemical flocculation main plate 203 (ferrous plate) in the electrochemical flocculation reaction tank 2 are electrified to generate iron ions as a flocculant, and micro-bubbles are further generated to take the oil in the water to the liquid surface and be scraped out to the floating sludge tank 8 through the first slag scraper 6 and the second slag scraper 7, meanwhile, the iron ions as the flocculant adsorb the pollutants in the water, enter the sludge-water separation tank 3 through the electrochemical water outlet tank 10, NaOH is added to adjust the pH value to about 8, PAM (the addition amount is one ten-thousandth of the water inlet amount) is added as a coagulant aid to accelerate sludge-water separation, the qualified supernatant is discharged through the water outlet 13, and the sludge at the bottom is discharged through the third sludge discharge port 301 through the separation plate.

[0041] In the description of the utility model, it is understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model.

[0042] In addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the utility model, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0043] In the utility model, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrated; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, it can be the communication or interaction relationship between two elements, unless otherwise specifically limited. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0044] In the utility model, unless otherwise specifically defined and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0045] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. Furthermore, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples, without contradiction.

[0046] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and are not to be construed as limiting the present application, and the person skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A fracturing flowback fluid treatment device based on an electrochemical method, characterized in that, The fracturing flowback fluid treatment device includes an electrochemical electrolytic demulsification reaction tank (1), an electrochemical flocculation reaction tank (2), and a mud-water separation tank (3); The outlet of the electrochemical electro-demulsification reaction tank (1) is connected to the inlet of the electrochemical flocculation reaction tank (2), and the outlet of the electrochemical flocculation reaction tank (2) is connected to the inlet of the mud-water separation tank (3).

2. The fracturing flowback fluid treatment device based on electrochemical method according to claim 1, characterized in that, The electrochemical electro-emulsifying reaction tank (1) includes an inlet pipe (4), a first inlet baffle (101), an electrochemical inert electrode plate (103), a first electrochemical inert main electrode plate (102), and a second electrochemical inert main electrode plate (104). The electrochemical electro-electrodemulsification reaction tank (1) is provided with the water inlet pipe (4) on its side wall. The electrochemical electro-electrodemulsification reaction tank (1) is provided with the first water inlet baffle (101), the first electrochemical inert main electrode plate (102), the electrochemical inert sub-electrode plate (103) and the second electrochemical inert main electrode plate (104) sequentially installed from the side closest to the water inlet pipe (4).

3. The fracturing flowback fluid treatment device based on electrochemical method according to claim 1, characterized in that, The top of the separating sidewall of the electrochemical electro-demulsification reaction tank (1) and the electrochemical flocculation reaction tank (2) is provided with a scum trough (8), and the bottom of the scum trough (8) is provided with a scum discharge port (9); the top of the inner sidewall of the scum trough (8) is provided with a first scum scraper (6) and a second scum scraper (7).

4. The fracturing flowback fluid treatment device based on electrochemical method according to claim 2, characterized in that, The electrochemical electro-electrodemulsification reaction tank (1) is provided with a first separation plate (106) and a second separation plate (107). The first separation plate (106) and the second separation plate (107) are inclined to the horizontal plane, and the lower edges of the first separation plate (106) and the second separation plate (107) are engaged with the corresponding bottom wall of the electrochemical electro-electrodemulsification reaction tank (1). The upper edges of the first separation plate (106) and the second separation plate (107) are engaged with the corresponding inner side wall of the electrochemical electro-electrodemulsification reaction tank (1). The bottom of the electrochemical electro-electrodemulsification reaction tank (1) is provided with a first sludge discharge port (105).

5. The fracturing flowback fluid treatment device based on electrochemical method according to claim 1, characterized in that, The electrochemical flocculation reaction tank (2) includes a second inlet baffle (207), an electrochemical flocculation electrode plate (202), a first electrochemical flocculation main electrode plate (201), and a second electrochemical flocculation main electrode plate (203); The electrochemical flocculation reaction tank (2) is equipped with the second water inlet baffle (207), the first electrochemical flocculation main electrode plate (201), the electrochemical flocculation sub-electrode plate (202) and the second electrochemical flocculation main electrode plate (203) sequentially from the side closest to the electrochemical electro-emulsification reaction tank (1).

6. The fracturing flowback fluid treatment device based on electrochemical method according to claim 1, characterized in that, The mud-water separation tank (3) is provided with a fifth separation plate (302) and a sixth separation plate (303). The fifth separation plate (302) and the sixth separation plate (303) are inclined to the horizontal plane, and the lower edge of the fifth separation plate (302) and the sixth separation plate (303) are joined to the bottom of the mud-water separation tank (3). The upper edge of the fifth separation plate (302) and the sixth separation plate (303) are joined to the inner wall of the mud-water separation tank (3). The bottom of the mud-water separation tank (3) is provided with a third mud outlet (301).

7. The fracturing flowback fluid treatment device based on electrochemical method according to claim 5, characterized in that, The electrochemical flocculation reaction tank (2) is provided with a third separation plate (205) and a fourth separation plate (206). The third separation plate (205) and the fourth separation plate (206) are inclined to the horizontal plane, and the lower edge of the third separation plate (205) and the fourth separation plate (206) are joined to the bottom of the electrochemical flocculation reaction tank (2). The upper edge of the third separation plate (205) and the fourth separation plate (206) are joined to the inner wall of the electrochemical flocculation reaction tank (2). The bottom of the electrochemical flocculation reaction tank (2) is provided with a second sludge discharge port (204).

8. The fracturing flowback fluid treatment device based on electrochemical method according to claim 1, characterized in that, An electrochemical reaction outlet tank (10) is installed on the upper end of the inner wall of the mud-water separation tank (3) near the electrochemical flocculation reaction tank (2); a stirrer (11) is installed inside the electrochemical reaction outlet tank (10).

9. The fracturing flowback fluid treatment device based on electrochemical method according to claim 1, characterized in that, A cleaning duct (5) is installed at the bottom of the electrochemical electro-demulsification reaction tank (1) and the electrochemical flocculation reaction tank (2).

10. A fracturing flowback fluid treatment device based on electrochemical method according to claim 6, characterized in that, A sedimentation zone outlet trough (12) is installed on the upper end of the side wall of the mud-water separation tank (3) away from the electrochemical flocculation reaction tank (2); the sedimentation zone outlet trough (12) is connected to an outlet.

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