Oil-water separation tank for oily sewage

Abstract

The invention relates to the technical field of oily sewage treatment, in particular to an oily sewage oil-water separation tank which comprises a tank body and an oil-water separator arranged in the tank body. The pool body is sequentially provided with a liquid inlet tank, a liquid separation tank, an overflow tank and a water storage tank in the water flow direction, the oil-water separator is arranged between the liquid inlet tank and the liquid separation tank, and the interior of the oil-water separator is composed of a plurality of partition plates to form a continuous flow channel. The oil-water separator sequentially comprises a horizontal separation section, a torsion reversing section and a vertical layering section, and a partition plate is arranged to be in a horizontal, inclined or vertical state in different sections according to structural requirements, so that oil drops are guided to gradually gather and float upwards, and effective oil-water separation is realized. The structure is compact, the separation efficiency is improved by utilizing the geometric design of the flow channel, the liquid flow direction is improved, and the liquid flow speed in the flow channel is improved. The oil-containing wastewater pretreatment or recycling system is suitable for industrial and environmental protection fields.

Description

Technical Field

[0001] The present invention relates to the technical field of oily sewage treatment, and particularly to an oily sewage oil-water separation tank. Background Art

[0002] At present, if a large amount of oily wastewater generated in industries such as metal processing, machinery manufacturing, and petrochemical industry is directly discharged, it will seriously pollute the environment and waste precious water resources. In the treatment of oily sewage, physical methods are widely used due to their low cost and high efficiency, mainly including the oil separation tank method, air flotation method, centrifugation method, and filtration method. The oil separation tank method utilizes the natural flotation principle of the density difference between oil and water, and is suitable for wastewater with larger oil droplet diameters and lower concentrations. However, the equipment has a large volume, occupies a large area, and has insufficient separation efficiency for fine or emulsified oil droplets. The air flotation method releases tiny bubbles into the water to make the oil droplets attach and float. Although it can remove emulsified oil droplets, it has high energy consumption and complex operation and maintenance. The centrifugal separation method accelerates the oil-water separation by means of high-speed centrifugal force and is suitable for high-concentration occasions. However, both the investment and energy consumption are high, and it is not suitable for the treatment of large-flow and low-concentration wastewater. The filtration separation method relies on the filter medium to intercept oil droplets and is suitable for small-flow fine treatment. However, it is prone to clogging, requires frequent replacement of the filter medium, and has a high operation cost. The hydrocyclone has a small volume, no moving parts, and can continuously process a large flow, but it is sensitive to the fluctuations of the inlet pressure and flow rate, and has a poor separation effect on small oil droplets.

[0003] In addition, the plate coalescence separator promotes the coalescence of oil droplets through inclined plates, without external power, has a smaller volume than the oil separation tank, and is easy to maintain. However, the upward floating direction of the oil droplets is opposite to the water flow direction, and the oil droplets must overcome the downward water flow resistance to coalesce and float to achieve oil-water separation. Therefore, the water velocity is limited (usually < 10 mm / s), which severely restricts the treatment capacity. Moreover, for large-flow treatment, multiple devices need to be connected in parallel, resulting in a complex system and an increased floor area.

[0004] In summary, the prior art has not solved the speed and efficiency bottlenecks caused by the reverse movement of oil droplets and water flow in plate coalescence separation. There is an urgent need for a new type of oil-water separation device with a compact structure, where the oil droplets and water flow in the same direction and can handle large flows. Summary of the Invention

[0005] In view of the above deficiencies or defects in the prior art, the present invention provides an oily sewage oil-water separation tank, which can efficiently stratify oily wastewater and has a higher water flow velocity compared to ordinary plate coalescence separators.

[0006] To achieve the above object, the present invention provides an oily sewage oil-water separation tank, comprising:

[0007] A tank body, which successively includes a liquid inlet tank, a liquid separation tank, an overflow tank, and a water storage tank according to the water flow direction of the separation tank;

[0008] The liquid inlet tank is connected to the inlet of the oil-water separator, and the outlet of the oil-water separator is connected to the liquid separation tank.

[0009] The liquid separation tank is provided with a first floating oil collector at the liquid level at the top, and has water passing holes in the lower half. The liquid separation tank is communicated with the overflow tank through the water passing holes, and the two form a communicating vessel.

[0010] The overflow tank has an overflow port at the top, and the water flowing out of the overflow port enters the water storage tank.

[0011] The water storage tank is provided with a water outlet at the lower half.

[0012] The oil-water separator: The oil-water separator includes a cylindrical outer wall, and multiple partition plates are arranged inside the outer wall. Flow channels extending from the inlet to the outlet are formed between the partition plates. The oil-water separator sequentially includes a horizontal separation section, a twisting and turning section, and a vertical stratification section from the inlet to the outlet.

[0013] The partition plates in the horizontal separation section are arranged horizontally, and the flow channels are wide in the left-right direction and narrow in the up-down direction.

[0014] The partition plates in the twisting and turning section gradually twist from a horizontal state to a vertical state.

[0015] The partition plates in the vertical stratification section are arranged vertically, and the flow channels are narrow in the left-right direction and wide in the up-down direction.

[0016] In some embodiments, the pool body further includes a sand settling tank, which is arranged in front of the water storage tank.

[0017] The inlet of the oily sewage is arranged in the middle of the side wall of the sand settling tank.

[0018] The bottom of the sand settling tank is provided with a sand discharge port.

[0019] A first weir plate is arranged at the top of the sand settling tank, and the oily sewage in the sand settling tank flows out from the top of the first weir plate and into the liquid inlet tank.

[0020] In some embodiments, a second floating oil collector is arranged at the liquid level at the top of the liquid inlet tank.

[0021] In some embodiments, the first floating oil collector is a floating oil collection tank, and a second weir plate is arranged at the oil inlet of the floating oil collection tank. The top of the second weir plate is flush with the liquid level of the liquid separation tank.

[0022] A third weir plate is arranged at the overflow port at the top of the overflow tank, and the third weir plate is flush with the liquid level height of the overflow tank.

[0023] The heights of the first weir plate, the second weir plate, and the third weir plate are all adjustable, and the top heights of the three weir plates are in descending order as the first weir plate, the second weir plate, and the third weir plate.

[0024] In some embodiments, the oil-water separator is inclined, and the outlet end of the oil-water separator is higher than its inlet end.

[0025] The included angle between the extending direction of the oil-water separator and the horizontal plane is α, and 5° ≤ α ≤ 30°.

[0026] In some embodiments, the inlet end of the oil-water separator is connected to the middle part of the side wall of the liquid inlet tank, and the outlet end of the oil-water separator is connected to the upper half of the side wall of the liquid separation tank.

[0027] A filter is detachably arranged at the inlet end of the oil-water separator.

[0028] The position of the water passing holes is lower than the outlet of the oil-water separator.

[0029] In some embodiments, the pool body further includes a mounting groove, and the oil-water separator is arranged in the mounting groove.

[0030] Water is contained in the mounting groove, and the water surface height is higher than that of the oil-water separator, and the oil-water separator is immersed in the water.

[0031] In some embodiments, the mounting groove is communicated with the overflow tank through a water guiding pipe, and the mounting groove and the overflow tank form a communicating vessel.

[0032] In some embodiments, the surface of the partition plate on the oil side is made of an oil-friendly material.

[0033] In some embodiments, the length of the horizontal separation section is greater than that of the vertical stratification section.

[0034] Applying the above technical solution of the present invention to an oil-containing sewage oil-water separation pool has the following effects:

[0035] The present invention provides an oil-containing sewage oil-water separation pool with a reasonable structure, which enables the oil droplets and the water flow to move in the same direction, reducing the water flow resistance for the oil droplets to float. Thus, the flow velocity of the liquid in the flow channel can be increased. It ingeniously integrates the oil-water separator into the pool body, and through the flow channel design and the synergistic effect of each functional section, the efficient separation and treatment of the oil-containing sewage are realized.

[0036] As the core component, the internal structure of the oil-water separator is designed in combination with the physical properties of oil and water itself. In the horizontal separation section, the partition plates are arranged horizontally to form a flow channel that is wide on the left and right and narrow on the top and bottom. For oil droplets, it only needs to float upward for a short distance to contact the top of the partition plate and converge on the top of the partition plate to form large oil droplets or an oil layer, which speeds up the oil-water separation speed. In the twisting and turning section, the partition plates gradually twist from the horizontal state to the vertical state, and the flow channel also deforms from horizontal extension to vertical extension accordingly. During this process, the oil layer and large oil droplets continuously gather upward along the increasingly inclined lower surface of the partition plates, further promoting the oil-water separation. In the vertical stratification section, the partition plates are arranged vertically to form a flow channel that is narrow on the left and right and wide on the top and bottom, enabling the oil stain to gather at the top of the flow channel and the water to be at the bottom, achieving a clear stratification of oil and water.

[0037] The separated oil stain will naturally float on the upper layer of the liquid separation tank to form an oil slick layer, and the first oil slick collector set at the top of the liquid separation tank can conveniently collect this part of the oil slick. The water in the lower layer flows back to the overflow tank through the water passing holes and finally flows into the water storage tank and is discharged from the water outlet of the water storage tank, realizing the recycling of water resources. This design not only improves the utilization rate of water resources, reduces water resource waste, but also reduces the overall operating cost, and is also beneficial to environmental protection. Brief Description of the Drawings

[0038] Figure 1 is a schematic diagram of the internal structure of the oil-water separation tank of the present invention;

[0039] Figure 2 is a side view of the oil-water separator in the present invention;

[0040] Figure 3 is Figure 2 a sectional view along A-A, that is, the initial section of the horizontal separation section in, and a part of it is enlarged;

[0041] Figure 4 is Figure 2 a sectional view along B-B, that is, the end section of the horizontal separation section in, and a part of it is enlarged;

[0042] Figure 5 is Figure 2 a sectional view along C-C, that is, the initial section of the twisting and turning section in, and a part of it is enlarged;

[0043] Figure 6 is Figure 2 a sectional view along D-D, that is, the middle section of the twisting and turning section in, and a part of it is enlarged;

[0044] Figure 7 is Figure 2 a sectional view along E-E, that is, the end section of the twisting and turning section in, and a part of it is enlarged;

[0045] Figure 8 is Figure 2 A sectional view along F-F, i.e., the vertical stratification section, in which a part is enlarged.

[0046] Description of the reference numerals

[0047] 1 - sedimentation tank, 1a - sand discharge port, 1b - first weir plate;

[0048] 2 - liquid inlet tank;

[0049] 3 - liquid separation tank;

[0050] 4 - overflow tank;

[0051] 5 - water storage tank;

[0052] 6 - installation tank;

[0053] 7 - water passing hole;

[0054] 8 - overflow opening, 8a - third weir plate;

[0055] 9 - water outlet;

[0056] 10 - oil-water separator, 10a - horizontal separation section, 10b - twist conversion section, 10c - vertical stratification section, 10d - outer wall, 10e - partition plate;

[0057] 11 - first floating oil collector, 11a - second weir plate;

[0058] 12 - second floating oil collector;

[0059] 13 - filter;

[0060] 14 - water inlet pipe. Detailed implementation manners

[0061] The following details the specific implementation manners of the present invention. It should be understood that the specific implementation manners described herein are only for explaining and illustrating the present invention, and are not used to limit the present invention.

[0062] In the present invention, unless otherwise stated, the orientation terms such as "upper" and "lower" generally refer to the orientation in the assembled and used state. "Inner" and "outer" refer to the inner and outer of the contour of each component itself.

[0063] The present invention provides an oil-containing sewage oil-water separation tank, including a tank body and an oil-water separator 10 integrated in the tank body. The technical solution of the present invention will be detailed below with reference to the accompanying drawings.

[0064] Introduction of the tank body part

[0065] Such as Figures 1-8As shown in the figure, the oil-containing sewage oil-water separation tank of the present invention includes a tank body, which is sequentially divided into a sand settling tank 1, a liquid inlet tank 2, a liquid separation tank 3, an overflow tank 4 and a water storage tank 5 along the water flow direction. The liquid levels of each tank form a liquid level gradient through the height difference of the retaining weir plates. The specific structure is as follows:

[0066] Sand settling tank 1, the sand settling tank 1 is located at the forefront of the tank body and is used to remove large particle solid impurities (such as sand and metal debris) in the oil-containing sewage. A sewage inlet containing oil is provided in the middle of its side wall, and a sand discharge port is provided at the bottom, and the sediment can be regularly cleaned through a valve. A first retaining weir plate 1b is provided at the top of the sand settling tank 1, and the oil-containing sewage overflows to the liquid inlet tank 2 through the top of the first retaining weir plate 1b, preventing solid impurities from entering the subsequent treatment unit.

[0067] Liquid inlet tank 2, the liquid inlet tank 2 is connected to the sand settling tank 1 and the oil-water separator 10, and is used to temporarily store the pretreated sewage and complete the preliminary oil-water separation. A second floating oil collector 12 (mechanical oil scraper or floating oil collecting tank) is provided at the liquid level at the top of the liquid inlet tank 2 to collect the floating oil on the surface of the sewage preliminarily separated in the liquid inlet tank 2. A floating matter collector can also be provided at the top of the liquid inlet tank 2 to clean the impurities floating on the water surface in the liquid inlet tank 2.

[0068] The inlet end of the oil-water separator 10 is connected to the middle of the side wall of the liquid inlet tank 2. This can prevent floating impurities from entering the oil-water separator 10 and causing blockage of the oil-water separator 10. And the water pressure in the middle of the liquid inlet tank 2 is relatively stable, avoiding the impact of the water flow overflowing from the sand settling tank 1 to the liquid inlet tank 2. At the same time, a detachable filter 13 (such as a stainless steel filter screen) is equipped at the inlet end to intercept residual fine particle impurities, and further stabilize the water flow entering the oil-water separator 10, reduce the water flow disturbance in the oil-water separator 10, and maintain the laminar flow state of the liquid in the flow channel of the oil-water separator 10.

[0069] Liquid separation tank 3, the liquid separation tank 3 is the core area for oil-water separation and receives the treatment liquid from the oil-water separator 10. The oil and water are introduced into different areas respectively.

[0070] A first floating oil collector 11 is provided at the top of the liquid separation tank 3, and a second retaining weir plate 11a with adjustable installation height is installed at its oil inlet. The top height of the second retaining weir plate 11a determines the liquid level height of the liquid separation tank 3. Water passing holes 7 are provided in the lower half of the liquid separation tank 3, which are communicated with the overflow tank 4 to form a communicating vessel structure, and the lower layer of clear water flows into the overflow tank 4 through the water passing holes 7. The first floating oil collector 11 is a floating oil collecting tank with an adjustable baffle.

[0071] Overflow tank 4, the overflow tank 4 is communicated with the liquid separation tank 3 through the water passing holes 7, and its main function is to receive the clear water separated by the liquid separation tank 3 and control the liquid level.

[0072] An overflow port 8 is provided at the top, and a third baffle 8a is installed at the overflow port 8. The height of the third baffle 8a is lower than that of the second baffle 11a of the liquid separation tank 3, forming a liquid level gradient.

[0073] The clear water overflows from the overflow port 8 to the water storage tank 5. The width of the overflow port 8 and the height of the baffle are adjustable to meet different flow requirements. The design of the overflow tank 4 ensures a stable liquid level and avoids the influence of liquid level fluctuations during pumping on the oil-water separation process in the liquid separation tank 3.

[0074] The water storage tank 5 is located at the end of the tank body and is used to store the clear water after multi-stage treatment. An outlet 9 is provided in the lower half of it, and the treated water can be recycled through a pipeline or discharged up to standard. If the water is directly pumped out from the liquid separation tank 3, the control requirements for the pumping flow rate and the inlet flow rate are extremely high, which is likely to cause instability in the liquid level height of the liquid separation tank 3 and cause a large disturbance to the water flow in the liquid separation tank 3. In the present invention, the clear water first enters the overflow tank 4 and flows into the water storage tank 5 from the overflow port 8 by utilizing its own liquid level gradient. Pumping the water from the water storage tank 5 will not affect the liquid level height of the liquid separation tank 3.

[0075] Without considering the density difference between the floating oil layer and water and when the liquid is stationary. The liquid level heights of the liquid inlet tank 2, the liquid separation tank 3, the overflow tank 4, and the installation tank 6 should be the same. In this application, the driving force for the liquid flow comes from the liquid level height difference in different areas of the tank body. Therefore, when the oil-water separation tank is working properly, the liquid level height is: liquid inlet tank 2 > liquid separation tank 3 > overflow tank 4 = installation tank 6. The height of the baffle is: first baffle 1b > second baffle 11a > third baffle 8a.

[0076] Introduction to the oil-water separator 10

[0077] The oil-water separator 10 is one of the core components of this system and is used to separate the oil-water mixture. The oil-water separator 10 mainly consists of a cylindrical outer wall 10d and a partition plate 10e. According to different functions, from one end to the other end of the oil-water separator 10, it can be divided into a horizontal separation section 10a, a twist and diversion section 10b, and a vertical stratification section 10c.

[0078] The cylindrical outer wall 10d is made of stainless steel, which has the characteristics of corrosion resistance and high strength. It can operate stably for a long time, resist the corrosion and erosion of the oil-water mixture, and ensure the service life of the equipment. The front and rear ends of the cylindrical outer wall 10d are the inlet and outlet respectively.

[0079] One side of the partition plate 10e (the lower surface of the horizontal separation section 10a and extending to the end of the partition plate 10e) is made of an oil-loving material or has an oil-loving coating on the surface, such as oil-loving polypropylene fibers, etc. The partition plate 10e in the horizontal separation section 10a is horizontally arranged, forming a flow channel that is wide from left to right and narrow from top to bottom. Oil droplets are easy to float up and contact the partition plate 10e and aggregate into an oil layer or large oil droplets.

[0080] The baffle plate 10e of the torsion turning section 10b gradually twists from the horizontal state to the vertical state. The flow channel deforms from a horizontal extension to a vertical extension, and the oil layer and large oil droplets gather upward along the lower surface of the inclined baffle plate 10e.

[0081] The baffle plate 10e of the vertical stratification section 10c is vertically arranged to form a flow channel that is narrow on the left and right and wide on the top and bottom. The oil stain gathers at the top of the flow channel, and the water is at the bottom.

[0082] The spacing of the baffle plates 10e is designed to be 10 - 30 mm, ensuring the full flow and separation of the oil-water mixture in the flow channel, while avoiding blockage and short-circuit phenomena.

[0083] Reference Figures 3-8 , and the gap between the baffle plates 10e is the flow channel.

[0084] The flow channel of the horizontal separation section 10a is wide on the left and right and narrow on the top and bottom (attached Figure 3 , 4 ), and the floating distance of the oil droplets is short, so they can quickly contact and gather with the baffle plate 10e. The flow channel of the torsion turning section 10b (attached Figure 5 , 6 , 7) changes with the torsion of the baffle plate 10e, prompting the oil droplets to continuously gather during the rising process. The flow channel of the vertical stratification section 10c (attached Figure 8 ) is narrow on the left and right and wide on the top and bottom, providing a clear space for the stratification after the oil-water separation. The upper layer is the oil stain, and the lower layer is the water.

[0085] In an embodiment of the present application, the length of the horizontal separation section 10a is set to be greater than that of the vertical stratification section 10c. The reason for this setting is that the forms of the oil-water mixture in the horizontal separation section 10a and the vertical stratification section 10c are different. In the horizontal separation section 10a, the oil stain is suspended and dispersed in the water in the form of small oil droplets, while in the vertical stratification section 10c, the oil droplets mainly exist in the form of large-diameter oil droplets or oil layers. According to Stokes' law, the radius (r) of the oil droplet is proportional to the square root of the rising velocity (v), that is, the larger the oil droplet, the faster it floats.

[0086] Since smaller droplets are more difficult to form a layer with water, the length of the horizontal separation section 10a is set to be greater than that of the vertical stratification section 10c. With a longer flow time of the liquid (oil-water mixture) in the horizontal separation section 10a, the small oil droplets can converge to the top of the flow channel, thus forming large-diameter oil droplets or oil layers. Then, in the vertical stratification section 10c, the small oil droplets have formed large-diameter oil droplets or oil layers. The large-diameter oil droplets have a fast floating speed and are easy to be stratified from the water. Therefore, the length of the vertical stratification section 10c can be set shorter, that is, shorter than the horizontal separation section 10a.

[0087] The length of the twist conversion section 10b is determined according to the liquid flow rate, the Reynolds number of the liquid, and the flow channel width, and the liquid is kept flowing in a laminar state in the twist conversion section 10b as much as possible.

[0088] As Figure 1 shown, the oil-water separator 10 is generally arranged horizontally with a certain inclination angle α (α is set to 5° - 30°), so that the outlet of the oil-water separator 10 is slightly higher than its inlet. On the one hand, it is convenient for the separated oil layer in the vertical stratification section 10c to be discharged from the outlet of the oil-water separator 10. On the other hand, it can prevent impurity deposition and improve the anti-blocking ability of the oil-water separator 10. The oil-water separator 10 is inclined upward, so heavier solid deposits are not easily introduced into the oil-water separator 10 and deposited in the oil-water separator 10. Lighter floating substances are also more likely to move obliquely upward along the water flow direction and flow out of the oil-water separator 10. In order to further avoid blockage of the oil-water separator 10, a filter 13 is detachably arranged at the inlet end of the oil-water separator 10. On the one hand, the filter 13 prevents larger impurities from entering the oil-water separator 10 and blocking the flow channel. On the other hand, it also has the function of stabilizing the water flow, reducing the disturbance at the inlet end of the oil-water separator 10, and being beneficial to the oil-water separation in the horizontal separation section 10a of the oil-water separator 10.

[0089] The installation groove 6 is in water level balance

[0090] The oil-water separator 10 is integrally embedded in the installation groove 6 of the pool body, and the installation groove 6 is filled with water until the water surface completely submerges the oil-water separator 10, and the buoyancy of the water is used to support the oil-water separator 10. It avoids the pressure of the liquid self-weight in the oil-water separator 10 on the flow channel and causes the flow channel to be deformed under pressure. The installation groove 6 is communicated with the overflow groove 4 through a water diversion pipe 14 to form a communicating vessel structure to ensure the synchronization of the water level.

[0091] Through the integrated design of the inclined oil-water separator 10, multi-stage weir plate liquid level control, and the sedimentation tank 1, the present invention significantly improves the oil-water separation efficiency, and is especially suitable for the treatment of large-flow oil-containing sewage. The flow channel structure of the oil-water separator 10 is optimized, and the oil droplets move in the same direction as the water flow, reducing the floating resistance of the oil droplets and allowing the water flow speed to be increased to 15 - 20 mm / s, and the treatment capacity is increased by more than 50% compared with the traditional plate coalescence separator. In addition, by adjusting the height of the adjustable weir plate, the liquid level height difference of each tank can be adjusted, and then the water flow speed in the flow channel can be adjusted. The water flow does not require additional power, and the operation cost is low.

[0092] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0093] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0094] In addition, any combination can be made among various different embodiments of the present invention, as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. An oily sewage oil-water separation tank, characterized in that, Comprising: A pool body, which sequentially includes a liquid inlet tank (2), a liquid separation tank (3), an overflow tank (4), and a water storage tank (5) according to the flow direction of water; The liquid inlet tank (2) is connected to the inlet of the oil-water separator (10), and the outlet of the oil-water separator (10) is connected to the liquid separation tank (3); The liquid separation tank (3) is provided with a first floating oil collector (11) at the liquid level at the top, and water passing holes (7) are provided in the lower half of the liquid separation tank (3). The liquid separation tank (3) and the overflow tank (4) are communicated through the water passing holes (7), and the two form a communicating vessel; The overflow tank (4) has an overflow port (8) at the top, and the water flowing out of the overflow port (8) enters the water storage tank (5); The water storage tank (5) is provided with a water outlet (9) in the lower half; The oil-water separator (10): The oil-water separator (10) includes a cylindrical outer wall (10d), and a plurality of partition plates (10e) are arranged inside the outer wall (10d). Flow channels extending from the inlet to the outlet are formed between the partition plates (10e); The oil-water separator (10) sequentially includes a horizontal separation section (10a), a twist and turning section (10b), and a vertical stratification section (10c) from the inlet to the outlet; The partition plates (10e) of the horizontal separation section (10a) are arranged horizontally, and the flow channel is wide in the left-right direction and narrow in the up-down direction; The partition plates (10e) of the twist and turning section (10b) are gradually twisted from a horizontal state to a vertical state; The partition plates (10e) of the vertical stratification section (10c) are arranged vertically, and the flow channel is narrow in the left-right direction and wide in the up-down direction.

2. The oil-containing sewage oil-water separation tank according to claim 1, characterized in that, The pool body further includes a sand settling tank (1), and the sand settling tank (1) is arranged in front of the water storage tank (5); The inlet of the oily sewage is arranged in the middle of the side wall of the sand settling tank (1); The bottom of the sand settling tank (1) is provided with a sand discharge port; A first retaining weir plate (1b) is arranged at the top of the sand settling tank (1); The oily sewage in the sand settling tank (1) flows out from the top of the first retaining weir plate (1b) and flows into the liquid inlet tank (2).

3. The oil-containing sewage oil-water separation tank according to claim 2, characterized in that, A second floating oil collector (12) is arranged at the liquid level at the top of the liquid inlet tank (2).

4. The oil-containing sewage oil-water separation tank according to claim 2, wherein The first floating oil collector (11) is a floating oil collection tank, and a second retaining weir plate (11a) is arranged at the oil inlet of the floating oil collection tank. The top of the second retaining weir plate (11a) is flush with the liquid level of the liquid separation tank (3); A third retaining weir plate (8a) is arranged at the overflow port (8) at the top of the overflow tank (4), and the third retaining weir plate (8a) is flush with the liquid level height of the overflow tank (4); The heights of the first retaining weir plate (1b), the second retaining weir plate (11a), and the third retaining weir plate (8a) are all adjustable, and the top heights of the three retaining weir plates are in descending order as the first retaining weir plate (1b), the second retaining weir plate (11a), and the third retaining weir plate (8a).

5. The oil-containing sewage oil-water separation tank according to claim 1, characterized in that, The oil-water separator (10) is inclined, and the outlet end of the oil-water separator (10) is higher than its inlet end; The included angle between the extending direction of the oil-water separator (10) and the horizontal plane is α, and 5° ≤ α ≤ 30°.

6. The oil-containing sewage oil-water separation tank according to claim 5, characterized in that, The inlet end of the oil-water separator (10) is connected to the middle of the side wall of the liquid inlet tank (2), and the outlet end of the oil-water separator (10) is connected to the upper half of the side wall of the liquid separation tank (3); The inlet end of the oil-water separator (10) is detachably provided with a filter (13); The position of the water passing hole (7) is lower than the outlet of the oil-water separator (10).

7. The oily sewage oil-water separation tank according to claim 1, characterized in that, The pool body further includes a mounting groove (6); the oil-water separator (10) is arranged in the mounting groove (6); Water is contained in the mounting groove (6), and the water surface height is higher than that of the oil-water separator (10), and the oil-water separator (10) is immersed in the water.

8. The oil-containing sewage oil-water separation tank according to claim 7, wherein, The mounting groove (6) is communicated with the overflow groove (4) through a water pipe (14), and the mounting groove (6) and the overflow groove (4) form a communicating vessel.

9. The oil-containing sewage oil-water separation tank according to claim 1, characterized in that, The surface of the partition plate (10e) on the oil side is made of a lipophilic material.

10. The oil-containing sewage oil-water separation tank according to claim 1, characterized in that, The length of the horizontal separation section (10a) is greater than that of the vertical stratification section (10c).

Images