Oilfield polymer mixing tank equipment

Abstract

This utility model relates to the field of oilfield polymer injection technology, and particularly to an oilfield polymer mixing tank device. The technical solution is as follows: the lower right side of the first mixing and preparation tank is connected to the main delivery pipe via a first drain pipe and a first delivery pump; the lower right side of the second mixing and preparation tank is connected to the main delivery pipe via a second drain pipe and a second delivery pump; the second drain pipe is connected to the inlet of the first mixing and preparation tank via a branch circulation pipe and a branch control valve; the lower right side of the aeration tank is connected to the inlet of the first mixing and preparation tank via an aeration tank drain pipe and an aeration tank delivery pump. Its beneficial effects are: this utility model uses an aeration tank to treat the divalent iron and chemical oxygen demand (COD) in the water, and the prepared water, after meeting the aeration standards, is sent to two sets of mixing and preparation tanks. The polymer solution is mixed according to the designed concentration, and then injected into the formation through an injection pump connected to the outer end of the main delivery pipe, thus realizing polymer injection into the oil well.

Description

Technical Field

[0001] This utility model relates to the field of oilfield polymer injection technology, and in particular to an oilfield polymer mixing tank device. Background Technology

[0002] With the continuous development of oil extraction technology, it is divided into three stages: primary oil recovery, secondary oil recovery, and tertiary oil recovery. In the secondary oil recovery stage, gas or water is injected into the oil reservoir to increase reservoir pressure, replenishing energy to the rocks and fluids in the formation, allowing formation fluids to flow to the oil well, thus enabling the extraction of liquids that cannot be extracted using natural energy alone. In the tertiary oil recovery stage, polymer flooding is used to alter the viscosity and adsorption of crude oil to rocks, increasing its flowability and further improving oil recovery rates.

[0003] Polymer flooding is a production enhancement measure that involves injecting polymers into the formation to displace oil. It has a viscosity-reducing and dispersing effect on heavy oil, and also exhibits good temperature resistance, allowing it to be used in conjunction with steam injection for heavy oil extraction. In field implementation, the conventional method involves mixing polymer dry powder with water in a specific ratio to form a solution, which is then injected into the oil layer. This is done by mixing the polymer into an existing mixing tank. However, since polymers are generally in solid particulate form, injecting them downhole without sufficient dissolution can negatively impact their oil displacement effect. Furthermore, the produced water from the wellhead contains high levels of ferrous iron (Fe2+) and chemical oxygen demand (COD). Ferrous iron ions can be oxidized to ferric iron (Fe3+) ions through aeration over a certain period, and the COD will also decrease. This method addresses both the ferrous iron and COD levels to meet standards, while also controlling the oxygen content of the prepared water to meet the requirements for injection underground. Utility Model Content

[0004] The purpose of this invention is to address the aforementioned deficiencies in the existing technology by providing an oilfield polymer mixing tank device. This device uses an aeration tank to treat the divalent iron and chemical oxygen demand (COD) in the water. The prepared water, after meeting the oxygenation standards, is then fed into two sets of mixing tanks to mix the polymer solution according to the designed concentration, thereby achieving a better oil displacement effect from the polymer.

[0005] The present invention discloses an oilfield polymer mixing tank device, the technical solution of which includes a first mixing and preparation tank (1), a second mixing and preparation tank (2), an aeration tank (3), a first drain pipe (4), a first delivery pump (5), a main delivery pipe (6), a second drain pipe (7), a second delivery pump (8), an aeration tank drain pipe (9), an aeration tank delivery pump (10), a branch circulation pipe (11), and a branch control valve (12). The lower right side of the first mixing and preparation tank (1) is connected to the main delivery pipe (6) through the first drain pipe (4) and the first delivery pump (5). The lower right side of the second mixing and preparation tank (2) is connected to the main delivery pipe (6) through the second drain pipe (7) and the second delivery pump (8). The second drain pipe (7) is connected to the first mixing and preparation tank (1) through the branch circulation pipe (11) and the branch control valve (12). Inlet; the lower right side of the aeration tank (3) is connected to the inlet of the first mixing tank (1) through the aeration tank drain pipe (9) and the aeration tank delivery pump (10); feed boxes (1.13) are installed on the left ends of the first mixing tank (1) and the second mixing tank (2), respectively, and the polymer is fed into the first mixing tank (1) and the second mixing tank (2) through the feed boxes (1.13); inlet box (3.1) is installed on the left end of the aeration tank (3), and the purified wellhead produced water is fed into the aeration tank (3) through the inlet box (3.1). One or more agitators are installed in the first mixing tank (1), the second mixing tank (2) and the aeration tank (3), respectively. The aeration tank (3) sends the purified wellhead produced water after aeration into the second mixing tank (2) through the aeration tank drain pipe (9) and the aeration tank delivery pump (10) on the right end of the aeration tank (3).

[0006] Preferably, the feed box (1.13) is provided with a feed inlet (1.2) on the outside, a feed box cleaning port (1.4) is provided on the top of the feed box (1.13), and a rinsing port (1.3) is provided on one side of the feed box (1.13).

[0007] Preferably, the top of the first mixing and preparation tank (1) is provided with a first stirring motor (1.7) and a second stirring motor (1.8). The output ends of the first stirring motor (1.7) and the second stirring motor (1.8) are connected to the inner cavity of the first mixing and preparation tank (1) through a stirring shaft, and stirring blades are installed on the stirring shaft.

[0008] Preferably, filters (1.14) are installed at the liquid outlets of the inner cavities of the first mixing tank (1), the second mixing tank (2), and the aeration tank (3); and sediment filters of level one or higher are installed at the bottom of the inner cavities of the first mixing tank (1), the second mixing tank (2), and the aeration tank (3) (1.15).

[0009] Preferably, the top of the first mixing tank (1), the second mixing tank (2) and the aeration tank (3) are provided with a first manhole (1.5), a second manhole (1.6), a first breather valve (1.11) and a second breather valve (1.12); and a spare discharge port (1.1) is provided at the bottom left end of the first mixing tank (1), the second mixing tank (2) and the aeration tank (3), respectively, and a second filter (1.16) is installed on one side of the spare discharge port (1.1).

[0010] Preferably, a main control valve (13) is installed on the second drain pipe (7). The lower right side of the second mixing tank (2) is divided into two paths through the second drain pipe (7) and the second delivery pump (8). One path is connected to the main delivery pipe (6), and the other path is connected to the feed box (1.13) of the first mixing tank (1) through the branch circulation pipe (11) and the branch control valve (12).

[0011] Preferably, the bottom of the inner cavity of the feed box (1.13) is a sloped structure, and the right end is connected to the first mixing tank (1) or the second mixing tank (2). The bottom of the inner cavity of the liquid inlet box (3.1) is a sloped structure, and the right end is connected to the aeration tank (3). Furthermore, a filter screen is installed at the right end of the inner cavity of the feed box (1.13) and the liquid inlet box (3.1).

[0012] Preferably, the top of the aeration tank (3) is provided with four or more sets of vent pipes (3.2).

[0013] The beneficial effects of this utility model are: This utility model uses an aeration tank to treat the divalent iron and chemical oxygen demand (COD) in the water. The prepared water after aeration treatment is sent into two sets of mixing tanks, where polymer solutions are mixed according to the designed concentration. Then, the polymer is injected into the formation through an injection pump connected to the outer end of the main delivery pipe, thereby realizing the oil well injection of polymer and improving the oil displacement effect of polymer underground. In addition, by adding a second branch pipe and a second branch control valve, and installing two sets of control valves on the branch circulation pipe, the second mixing tank and the first mixing tank can work alternately, achieving more flexible polymer injection. Furthermore, the outlet of the aeration tank is equipped with a filter, which can effectively block sediment. Regular cleaning and maintenance are required during use to ensure the quality of the prepared water. Attached Figure Description

[0014] Figure 1 This is a top view of the structure of this utility model; Figure 2 This is a schematic diagram of the end structure of this utility model; Figure 3 This is a side view of the structure of the first mixing and preparation tank; Figure 4 This is a side view of the filter of this utility model; Figure 5 This is a structural schematic diagram of Embodiment 2 of this utility model; In the diagram above: 1. First mixing and preparation tank; 2. Second mixing and preparation tank; 3. Aeration tank; 4. First drain pipe; 5. First transfer pump; 6. Main transfer pipe; 7. Second drain pipe; 8. Second transfer pump; 9. Aeration tank drain pipe; 10. Aeration tank transfer pump; 11. Branch circulation pipe; 12. Branch control valve; and 13. Main control valve. 1.1 Spare outlet, 1.2 Inlet, 1.3 Rinse outlet, 1.4 Feed box cleaning outlet, 1.5 First manhole, 1.6 Second manhole, 1.7 First stirring motor, 1.8 Second stirring motor, 1.9 Outlet, 1.10 Level gauge outlet, 1.11 First breather valve, 1.12 Second breather valve, 1.13 Feed box, 1.14 Filter, 1.15 Sediment filter, 1.16 Second filter, 3.1 Liquid inlet tank, 3.2 Vent pipe. Detailed Implementation

[0015] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0016] Example 1, referring to Figures 1-4This utility model discloses an oilfield polymer mixing tank device, comprising a first mixing and preparation tank 1, a second mixing and preparation tank 2, an aeration tank 3, a first drain pipe 4, a first delivery pump 5, a main delivery pipe 6, a second drain pipe 7, a second delivery pump 8, an aeration tank drain pipe 9, an aeration tank delivery pump 10, a branch circulation pipe 11, and a branch control valve 12. The first mixing and preparation tank 1 has a discharge port 1.9 on its lower right side, which is connected to the main delivery pipe 6 via the first drain pipe 4 and the first delivery pump 5. The second mixing and preparation tank 2 also has a discharge port on its lower right side, which is connected to the main delivery pipe 6 via the second drain pipe 7 and the second delivery pump 8. The second drain pipe 7 is connected to the first mixing and preparation tank 1 via the branch circulation pipe 11 and the branch control valve 12. The aeration tank 3 has an inlet; the lower right side of the aeration tank 3 has an outlet, which is connected to the inlet of the first mixing tank 1 through the aeration tank drain pipe 9 and the aeration tank delivery pump 10; the left ends of the first mixing tank 1 and the second mixing tank 2 are respectively equipped with feed boxes 1.13, and the polymer is fed into the first mixing tank 1 and the second mixing tank 2 through the feed boxes 1.13 respectively; the left end of the aeration tank 3 is equipped with an inlet box 3.1, and the purified wellhead produced water is fed into the aeration tank 3 through the inlet box 3.1. One or more agitators are installed in the first mixing tank 1, the second mixing tank 2 and the aeration tank 3 respectively. The right end of the aeration tank 3 is fed into the second mixing tank 2 through the aeration tank drain pipe 9 and the aeration tank delivery pump 10.

[0017] The feed box 1.13 is provided with a feed inlet 1.2 on the outside, a feed box cleaning port 1.4 on the top of the feed box 1.13, and a rinsing port 1.3 on one side of the feed box 1.13.

[0018] The top of the first mixing and preparation tank 1 is provided with a first stirring motor 1.7 and a second stirring motor 1.8. The output ends of the first stirring motor 1.7 and the second stirring motor 1.8 are connected to the inner cavity of the first mixing and preparation tank 1 through a stirring shaft, and stirring blades are installed on the stirring shaft.

[0019] A filter 1.14 is installed at the liquid outlet of the inner cavity of the first mixing and preparation tank 1, the second mixing and preparation tank 2, and the aeration tank 3 respectively; a sediment filter 1.15 of level one or higher is installed at the bottom of the inner cavity of the first mixing and preparation tank 1, the second mixing and preparation tank 2, and the aeration tank 3 respectively.

[0020] The top of the first mixing tank 1, the second mixing tank 2, and the aeration tank 3 is equipped with a first manhole 1.5, a second manhole 1.6, a first breather valve 1.11, and a second breather valve 1.12; a spare discharge port 1.1 is provided at the bottom left end of the first mixing tank 1, the second mixing tank 2, and the aeration tank 3, and a second filter 1.16 is installed on one side of the spare discharge port 1.1.

[0021] The main control valve 13 is installed on the second drain pipe 7. The lower right side of the second mixing tank 2 is divided into two paths through the second drain pipe 7 and the second delivery pump 8. One path is connected to the main delivery pipe 6, and the other path is connected to the feed box 1.13 of the first mixing tank 1 through the branch circulation pipe 11 and the branch control valve 12.

[0022] The bottom of the inner cavity of the feed box 1.13 is a sloping structure, and its right end is connected to the first mixing tank 1 or the second mixing tank 2. The bottom of the inner cavity of the liquid inlet box 3.1 is a sloping structure, and its right end is connected to the aeration tank 3. Furthermore, a filter screen is installed at the right end of the inner cavity of the feed box 1.13 and the liquid inlet box 3.1.

[0023] When using this utility model, First, the purified wellhead water is injected into the inlet tank 3.1 at the left end of the aeration tank 3. The purified wellhead water then passes through an inclined plane and a filter screen into the inner cavity of the aeration tank 3. It then passes through a sediment filter 1.15 with at least one stage inside the aeration tank 3 to filter out large particles of dirt. Then, under the continuous stirring of multiple agitators, air is connected to the aeration tank 3 through four or more sets of vent pipes 3.2 to aerate the ferrous iron and chemical oxygen demand (COD) in the water. The aeration degree is controlled by adjusting the stirring time to ensure that the ferrous iron and COD are treated to meet the standards, and the oxygen content of the prepared water is also controlled to meet the standards. Finally, after passing the on-site water quality test, the water is connected to the inlet of the first mixing and preparation tank 1 through the aeration tank drain pipe 9 and the aeration tank delivery pump 10. In addition, the outlet of the aeration tank 3 is equipped with a filter 1.14, which can effectively block sediment. Regular cleaning and maintenance are required during use to ensure the quality of the prepared water. The second step involves feeding the aeration-treated water into the second mixing tank 2 via the aeration tank 3. The polymer solution is then mixed according to the designed concentration. The polymer dry powder is fed into the feed box 1.13 of the second mixing tank 2 via the negative pressure feeding system. After mixing with the water from the aeration tank 3, the mixture flows into the inner cavity of the second mixing tank 2. Under the continuous stirring of multiple agitators, the mixture is made uniform and easier to dissolve during preparation. The third step involves closing the main control valve 13 and opening the branch control valve 12. The prepared liquid from the second mixing and preparation tank 2 is then fed into the first mixing and preparation tank 1 via the second delivery pump 8, the second drain pipe 7, and the branch circulation pipe 11. After further mixing in the first mixing and preparation tank 1, the liquid is filtered through the filter 1.14 at the outlet of the first mixing and preparation tank 1 and then fed into the main delivery pipe 6 via the first delivery pump 5 and the first drain pipe 4. Finally, it is injected into the formation through the injection pump connected to the outer end of the main delivery pipe 6, thereby realizing the oil well injection of polymer and improving the oil displacement effect of polymer underground.

[0024] Example 2: An oilfield polymer mixing tank device mentioned in this utility model includes a first mixing and preparation tank 1, a second mixing and preparation tank 2, an aeration tank 3, a first drain pipe 4, a first delivery pump 5, a main delivery pipe 6, a second drain pipe 7, a second delivery pump 8, an aeration tank drain pipe 9, an aeration tank delivery pump 10, a branch circulation pipe 11, and a branch control valve 12. The lower right side of the first mixing and preparation tank 1 has a discharge port 1.9, which is connected to the main delivery pipe 6 via the first drain pipe 4 and the first delivery pump 5. The lower right side of the second mixing and preparation tank 2 also has a discharge port, which is connected to the main delivery pipe 6 via the second drain pipe 7 and the second delivery pump 8. The second drain pipe 7 is connected to the first mixing and preparation tank 2 via the branch circulation pipe 11 and the branch control valve 12. The inlet of tank 1; the lower right side of the aeration tank 3 is provided with a discharge port, which is connected to the inlet of the first mixing and preparation tank 1 through the aeration tank drain pipe 9 and the aeration tank delivery pump 10; the left ends of the first mixing and preparation tank 1 and the second mixing and preparation tank 2 are respectively equipped with feed boxes 1.13, and the polymer is fed into the first mixing and preparation tank 1 and the second mixing and preparation tank 2 through the feed boxes 1.13 respectively; the left end of the aeration tank 3 is equipped with a liquid inlet box 3.1, and the purified wellhead produced water is fed into the aeration tank 3 through the liquid inlet box 3.1. One or more agitators are installed in the first mixing and preparation tank 1, the second mixing and preparation tank 2 and the aeration tank 3 respectively. The right end of the aeration tank 3 is connected to the second mixing and preparation tank 2 through the aeration tank drain pipe 9 and the aeration tank delivery pump 10.

[0025] The difference from Example 1 is: Reference Figure 5 In this embodiment, a second branch pipe 9.1 is provided at the end of the aeration tank drain pipe 9. A second branch control valve 9.2 is installed on the second branch pipe 9.1. The other end of the second branch pipe 9.1 is connected in parallel to the branch circulation pipe 11 at the liquid inlet of the first stirring and mixing tank 1.

[0026] In this embodiment, when the second mixing and preparation tank 2 is used directly, the main control valve 13 is opened and the branch control valve 12 is closed. This allows the liquid prepared by the second mixing and preparation tank 2 to be directly injected into the main delivery pipe 6 through the second delivery pump 8 and the second drain pipe 7. Then, it is directly injected into the formation through the injection pump connected to the outer end of the main delivery pipe 6, thereby realizing the oil well injection of polymer and improving the oil displacement effect of polymer underground.

[0027] Meanwhile, by controlling the aeration tank drain pipe 9 installed in the aeration tank 3, the prepared water after aeration treatment can be directly sent into the first mixing tank 1, so that the polymer can be stirred and mixed in the first mixing tank 1. By adding a second branch pipe 9.1 and a second branch control valve 9.2, and installing two sets of control valves on the branch circulation pipe 11, the second mixing tank 2 and the first mixing tank 1 can work alternately, achieving more flexible polymer injection.

[0028] The above description is merely a preferred embodiment of this utility model. Any person skilled in the art may modify this utility model or modify it into an equivalent technical solution using the technical solutions described above. Therefore, any simple modifications or equivalent transformations made based on the technical solutions of this utility model are within the scope of protection claimed by this utility model.

Claims

1. An oilfield polymer mixing tank device, characterized in that: Including the first The mixing tank (1), the second mixing tank (2), the aeration tank (3), the first drain pipe (4), the first delivery pump (5), the main delivery pipe (6), the second drain pipe (7), the second delivery pump (8), the aeration tank drain pipe (9), the aeration tank delivery pump (10), the branch circulation pipe (11), and the branch control valve (12) are arranged in a series of components. The lower right side of the first mixing tank (1) is connected to the main delivery pipe (6) through the first drain pipe (4) and the first delivery pump (5). The lower right side of the second mixing tank (2) is connected to the main delivery pipe (6) through the second drain pipe (7) and the second delivery pump (8). The second drain pipe (7) is connected to the inlet of the first mixing tank (1) through the branch circulation pipe (11) and the branch control valve (12). The lower right side of the aeration tank (3) is connected to the main delivery pipe (6) through the branch circulation pipe (11) and the branch control valve (12). The aeration tank is connected to the inlet of the first mixing tank (1) via the aeration tank drain pipe (9) and the aeration tank delivery pump (10). Feed boxes (1.13) are installed at the left ends of the first mixing tank (1) and the second mixing tank (2), respectively. The polymer is fed into the first mixing tank (1) and the second mixing tank (2) via the feed boxes (1.13). The aeration tank (3.1) is installed at the left end of the aeration tank (3). The purified wellhead water is fed into the aeration tank (3) via the feed boxes (3.1). One or more agitators are installed in the first mixing tank (1), the second mixing tank (2) and the aeration tank (3), respectively. The aeration tank (3) sends the purified wellhead water after aeration to the second mixing tank (2) via the aeration tank drain pipe (9) and the aeration tank delivery pump (10) at the right end of the aeration tank (3).

2. The oilfield polymer mixing tank device according to claim 1, characterized in that: The feed box (1.13) has a feed inlet (1.2) on the outside, a feed box cleaning port (1.4) on the top of the feed box (1.13), and a rinsing port (1.3) on one side of the feed box (1.13).

3. The oilfield polymer mixing tank device according to claim 2, characterized in that: The top of the first mixing and preparation tank (1) is provided with a first stirring motor (1.7) and a second stirring motor (1.8). The output ends of the first stirring motor (1.7) and the second stirring motor (1.8) are connected to the inner cavity of the first mixing and preparation tank (1) through a stirring shaft, and stirring blades are installed on the stirring shaft.

4. The oilfield polymer mixing tank device according to claim 3, characterized in that: in Filters (1.14) are installed at the liquid outlets of the inner cavities of the first mixing tank (1), the second mixing tank (2), and the aeration tank (3); sediment filters of level one or higher are installed at the bottom of the inner cavities of the first mixing tank (1), the second mixing tank (2), and the aeration tank (3) (1.15).

5. The oilfield polymer mixing tank device according to claim 4, characterized in that: The top of the first mixing tank (1) and the second mixing tank (2) are provided with a first manhole (1.5), a second manhole (1.6), a first breather valve (1.11) and a second breather valve (1.12); a spare discharge port (1.1) is provided at the bottom left end of the first mixing tank (1) and the second mixing tank (2), and a second filter (1.16) is installed on one side of the spare discharge port (1.1).

6. The oilfield polymer mixing tank device according to claim 5, characterized in that: The main control valve (13) is installed on the second drain pipe (7). The lower right side of the second mixing tank (2) is divided into two paths through the second drain pipe (7) and the second delivery pump (8). One path is connected to the main delivery pipe (6), and the other path is connected to the feed box (1.13) of the first mixing tank (1) through the branch circulation pipe (11) and the branch control valve (12).

7. The oilfield polymer mixing tank device according to claim 6, characterized in that: The bottom of the inner cavity of the feed box (1.13) is a sloping structure, and the right end is connected to the first mixing tank (1) or the second mixing tank (2). The bottom of the inner cavity of the liquid inlet box (3.1) is a sloping structure, and the right end is connected to the aeration tank (3). Furthermore, a filter screen is installed at the right end of the inner cavity of the feed box (1.13) and the liquid inlet box (3.1).

8. The oilfield polymer mixing tank device according to claim 7, characterized in that: The top of the aeration tank (3) is provided with four or more sets of vent pipes (3.2).

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