Oil-water separation system

Abstract

The invention relates to the technical field of sewage treatment, liquid separation and resource recycling, in particular to an oil-water separation system which comprises an oil-water separator and a liquid separation box. A liquid collecting tank is arranged at the bottom of the spray tower, and a liquid outlet of the liquid collecting tank is connected with the oil-water separator. The oil-water separator comprises a cylindrical outer wall, a plurality of partition plates are arranged in the outer wall, and flow channels extending from the inlet to the outlet are formed among the partition plates; the oil-water separator sequentially comprises a horizontal separation section, a torsion reversing section and a vertical layering section from an inlet to an outlet. A partition plate of the horizontal separation section is horizontally arranged; a partition plate of the torsion reversing section is gradually twisted from a horizontal state to a vertical state; partition plates of the vertical layering section are vertically arranged; an outlet of the oil-water separator is connected with a liquid separation box, and a floating oil collector is arranged at the top liquid level of the liquid separation box. According to the technical scheme, the device for efficiently separating and regenerating the oil-water mixture generated by the spray tower is provided.

Description

Technical Field

[0001] The present invention relates to the technical fields of sewage treatment, liquid separation and resource recycling, and particularly relates to an oil-water separation system. Background Art

[0002] In the field of gas purification, a spray tower (also known as a spray column) is a common device for washing solid and liquid impurities in waste gas. Its working principle is to achieve the absorption and washing of pollutants through the contact of gas-liquid two phases. The internal structure of the spray tower is relatively simple, without packing, and only nozzles are installed in the tower to atomize the liquid. During operation, the oil-containing mist flows from bottom to top and contacts the atomized spray water reversely, thereby completing the mass transfer and separation process.

[0003] The bottom of the traditional spray tower is equipped with a liquid collecting tank for collecting the spray water and the oil stains mixed therein. The oil-water mixture in the liquid collecting tank is stratified depending on the density difference of itself. Generally, two discharge ports, an upper one for discharging oil and a lower one for discharging water, are arranged on the liquid collecting tank to discharge the stratified oil and water respectively.

[0004] However, it is found in actual operation that the continuously falling spray water forms continuous impacts on the water surface in the liquid collecting tank. This impact seriously affects the stratification effect of oil and water, making the performance of the traditional spray tower in the key link of oil-water separation unsatisfactory, restricting the overall performance, and there is an urgent need for a more efficient oil-water separation system to solve this problem. Summary of the Invention

[0005] In view of the above deficiencies or defects in the prior art, the present invention provides an oil-water separation system which can separate the oil-water mixture in the spray tower and realize resource recycling.

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

[0007] A spray tower, the bottom of which is provided with a liquid collecting tank, and the liquid outlet of the liquid collecting tank is connected to an oil-water separator;

[0008] The oil-water separator includes a cylindrical outer wall, and a plurality of partition plates are arranged inside the outer wall, and 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 twist and diversion section, and a vertical stratification section from the inlet to the outlet;

[0009] 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;

[0010] The partition plates in the twist and diversion section are gradually twisted from the horizontal state to the vertical state;

[0011] The partition plate of the vertical stratification section is vertically arranged, the flow channel is narrow in the left-right direction and wide in the up-down direction;

[0012] Liquid separation tank, the outlet of the oil-water separator is connected to the liquid separation tank, and an oil slick collector is arranged at the liquid level at the top of the liquid separation tank.

[0013] In some embodiments, the liquid outlet of the liquid collection tank is connected to a water pump, and the water pump is connected to a water distributor. A water storage cavity is arranged in the water distributor, and the inlet of the oil-water separator communicates with the water storage tank of the water distributor.

[0014] In some embodiments, a flow guide plate is arranged in the water storage cavity, and the liquid in the water distributor flows into each flow channel of the oil-water separator in a laminar flow state through the flow guide plate.

[0015] In some embodiments, a backwash drain port is arranged at the bottom of the water distributor.

[0016] In some embodiments, the liquid separation tank includes a liquid separation groove, an overflow groove and a water storage groove; the outlet of the oil-water separator is connected to the liquid separation groove, and the oil slick collector is arranged at the top of the liquid separation groove; the liquid separation groove and the overflow groove are communicated through a water passing hole, and the two form a communicating vessel; the water passing hole is arranged in the lower half of the liquid separation groove; the top of the overflow groove is provided with an overflow port, and the water flowing out of the overflow port enters the water storage groove; the water storage groove is provided with the water outlet of the liquid separation tank.

[0017] In some embodiments, the oil-water separation system further includes a spray water tank. The water outlet of the water distribution tank is connected to the inlet of the spray water tank, and the outlet of the spray water tank is connected to the spray heads in the spray tower.

[0018] In some embodiments, the oil-water separator is horizontally arranged, and the outlet of the oil-water separator is located in the upper half of the liquid separation groove. The position of the water passing hole is lower than the outlet of the oil-water separator.

[0019] In some embodiments, the oil slick collector is an oil slick collection tank or an oil scraper.

[0020] In some embodiments, the surface of the partition plate on the side close to the oil is made of an oil-loving material.

[0021] In some embodiments, the length of the horizontal separation section is greater than that of the vertical stratification section.

[0022] An oil-water separation system applying the above technical solution of the present invention has the following effects:

[0023] The present invention provides an independent oil-water separation system outside the spray tower, and directly introduces the oil-water mixture collected in the liquid collection tank of the spray tower into this system for separation operation. As the core component, the unique internal structure design of the oil-water separator makes the separation process efficient and accurate.

[0024] The oil-water separator is divided by partition plates to form multiple liquid flow channels, and the design of these channels fully considers the physical properties of oil and water. In the horizontal separation section, the partition plates are arranged horizontally, making the channels wide in the left-right direction and narrow in the up-down direction. This layout is conducive to the oil droplets quickly floating upward by virtue of their density advantage and contacting the partition plates, forming an oil layer or large oil droplets, which greatly shortens the distance for the oil droplets to float up to the partition plates.

[0025] In the twist and diversion section, the partition plates gradually twist from the horizontal state to the vertical state, and the flow channels also deform from horizontal extension to vertical extension accordingly. During this process, the oil layer and large oil droplets continuously gather upward along the inclined lower surface of the partition plates, promoting further separation of oil and water.

[0026] In the vertical stratification section, there are multiple flow channels spaced in the left-right direction. At this time, the oil and dirt in the flow channels have gathered to the top of the flow channels, and the water is at the bottom of the flow channels. When the liquid flows out of the outlet of the oil-water separator, the upper layer is the oil and dirt, and the lower layer is the water, realizing clear stratification of oil and water.

[0027] The separated oil and dirt will naturally float on the upper layer of the liquid separation tank to form a floating oil layer, and the floating oil collector set at the top of the liquid separation tank can conveniently collect this part of the floating oil. The water in the lower layer can be recycled. 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

[0028] Figure 1 is a schematic diagram of the overall structure of the oil-water separation system of the present invention;

[0029] Figure 2 is a side view of the oil-water separator of the present invention;

[0030] Figure 3 is Figure 2 a sectional view along A-A in, that is, the initial section of the horizontal separation section, and a part of it is enlarged;

[0031] Figure 4 is Figure 2 a sectional view along B-B in, that is, the end section of the horizontal separation section, and a part of it is enlarged;

[0032] Figure 5 is Figure 2 a sectional view along C-C in, that is, the initial section of the twist and diversion section, and a part of it is enlarged;

[0033] Figure 6 is Figure 2 a sectional view along D-D in, that is, the middle section of the twist and diversion section, and a part of it is enlarged;

[0034] Figure 7 isFigure 2 In the figure, it is a sectional view of the end E-E of the twisting and redirecting section, and a part of it is enlarged;

[0035] Figure 8 is Figure 2 In the figure, it is a sectional view along F-F, that is, the vertical stratification section, and a part of it is enlarged;

[0036] Figure 9 It is a schematic diagram of the working principle of the liquid separation tank.

[0037] Explanation of reference numerals

[0038] 1 - Spray tower, 1a - Liquid collection tank, 1b - Air inlet, 1c - Air outlet;

[0039] 2 - Water pump;

[0040] 3 - Water separator, 3a - Backwashing drain outlet;

[0041] 4 - Oil-water separator, 4a - Horizontal separation section, 4b - Twisting and redirecting section, 4c - Vertical stratification section, 4d - Outer wall, 4e - Partition plate, 4f - Flow channel

[0042] 5 - Liquid separation tank, 5a - Liquid separation tank, 5b - Overflow tank, 5c - Water storage tank, 5d - Water passing hole; 5e - Overflow port

[0043] 6 - Floating oil collector;

[0044] 7 - Spray water tank. Detailed implementation manners

[0045] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and implementation manners. It should be understood that the specific implementation manners described herein are only used to explain the present invention and are not used to limit the present invention.

[0046] 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.

[0047] It should be noted that the spray tower 1 is the object of action of the oil-water separation system of the present invention, that is, the oil-water separation system of the present invention can be used for the spray tower 1. Of course, the technical solution of the present invention can also be used for equipment of the same type as the spray tower 1. Here, the spray tower 1 will be taken as an example to introduce the technical solution of this application.

[0048] The structure of the spray tower 1 includes a tower body, an air inlet 1b, a spray layer, a packing layer, an air outlet 1c, etc. The spray layer is equipped with high-efficiency nozzles, which can evenly spray the spray liquid on the oil mist, increase the gas-liquid contact area, and capture the oil droplets in the oil mist. A liquid collecting tank 1a is arranged at the bottom of the spray tower 1 for collecting the liquid containing oil stains. The liquid drips into the liquid collecting tank 1a and forms an oil-water mixture in the liquid collecting tank 1a. The liquid collecting tank 1a can be set as a conical structure with a large upper space and a small lower space, and the liquid outlet of the liquid collecting tank 1a is arranged at the top of the cone. The liquid outlet of the liquid collecting tank 1a is connected to a water pump 2, and the water pump 2 pumps out the oil-water mixture and transports it to a water separator 3. The type selection of the water pump 2 is determined according to the treatment capacity and system resistance of the spray tower 1, and it needs to have the characteristics of corrosion resistance and stable operation to adapt to the working conditions of the spray tower 1.

[0049] An oil-water separation system provided by the present invention includes an oil-water separator 4. The oil-water separator 4 is one of the core components of this system and is used to separate the oil-water mixture. The oil-water separator 4 is arranged horizontally and is mainly composed of a cylindrical outer wall 4d and a partition plate 4e. According to different functions, one end to the other end of the oil-water separator 4 can be divided into a horizontal separation section, a twist and diversion section, and a vertical stratification section.

[0050] The cylindrical outer wall 4d is made of stainless steel material, which has the characteristics of corrosion resistance and high strength, 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 4d are respectively an inlet and an outlet. The inlet and outlet are set in the form of flanges for easy connection with other equipment.

[0051] One side of the partition plate 4e (the lower surface of the horizontal separation section and extending to the end of the partition plate 4e) is a lipophilic material or a lipophilic coating is provided on the surface, such as lipophilic polypropylene fiber, etc. The partition plate 4e in the horizontal separation section is arranged horizontally to form a flow channel 4f that is wide left and right and narrow up and down, and the oil droplets are easy to float up and contact the partition plate 4e and aggregate into an oil layer or large oil droplets.

[0052] The partition plate 4e of the twist and diversion section 4b gradually twists from a horizontal state to a vertical state. The flow channel 4f extends 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 partition plate 4e.

[0053] The partition plate 4e of the vertical stratification section 4c is arranged vertically to form a flow channel 4f that is narrow left and right and wide up and down. The oil stain gathers at the top of the flow channel 4f, and the water is at the bottom.

[0054] The spacing of the partition plates 4e is designed to be 10 - 30 mm to ensure that the oil-water mixture flows and separates fully in the flow channel 4f, and at the same time avoid blockage and short-circuit phenomena.

[0055] Reference Figures 3 - 8 The gap between the partition plates 4e is the flow channel 4f.

[0056] The flow channel 4f of the horizontal separation section 4a is wider left and right and narrower up and down (attached Figure 3 、 4 ), the floating distance of the oil droplets is short, and they can quickly contact and aggregate with the partition plate 4e. The flow channel 4f of the twisting and turning section (attached Figure 5 、 6 、7) changes as the partition plate 4e twists, prompting the oil droplets to continuously aggregate during the rising process. The flow channel 4f of the vertical stratification section 4c (attached Figure 8 ) is narrower left and right and wider up and down, providing a clear space for the stratification after the oil-water separation. The upper layer is oil stain and the lower layer is water.

[0057] In an embodiment of the present application, the length of the horizontal separation section 4a is set to be greater than that of the vertical separation section 4c. The reason for this setting is that the forms of the oil-water mixture in the horizontal separation section 4a and the vertical separation section 4c are different. In the horizontal separation section 4a, the oil stain is suspended and dispersed in water in the form of small oil droplets, while in the vertical stratification section 4c, 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.

[0058] Since it is more difficult for smaller droplets to form a layer with water, the length of the horizontal separation section 4a is set to be greater than that of the vertical stratification section 4c. With a longer flow time of the liquid (oil-water mixture) in the horizontal separation section 4a, the small oil droplets can converge to the top of the flow channel 4f, thus forming large-diameter oil droplets or oil layers. Then, in the vertical stratification section 4c, 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 water. Therefore, the length of the vertical stratification section 4c can be set shorter, that is, shorter than the horizontal separation section 4a.

[0059] The length of the twisting and turning section is determined according to the liquid flow rate, the Reynolds number of the liquid, and the width of the flow channel 4f, and the liquid is kept flowing in a laminar state in the twisting and turning section 4b as much as possible.

[0060] As Figure 1 and Figure 9 shown, the water and oil stain that have completed stratification in the oil-water separator 4 need to flow to different destinations in the liquid separation tank 5.

[0061] After the oil and water are stratified in the oil-water separator 4, they flow into the liquid separation tank 5. An oil skimmer 6 is arranged at the liquid level position at the top of the liquid separation tank 5, and the oil skimming work can be completed, and the oil stain collected by the oil skimmer 6 is pumped away by a pipeline. The lower layer of the liquid separation tank 5 is water. If the water is directly pumped through the water outlet connecting the lower half of the liquid separation tank 5, this method has extremely high requirements for controlling the water flow rate, and the liquid level fluctuates greatly, affecting the normal operation of the oil skimmer 6.

[0062] Therefore, the present application optimizes the design of the liquid separation tank 5. A partition is arranged inside the tank to divide the tank into a liquid separation tank 5a, an overflow tank 5b and a water storage tank 5c. The separated liquid first enters the liquid separation tank 5a, and an oil skimmer 6 is provided at the top of the tank for collecting floating oil. The liquid separation tank 5a and the overflow tank 5b are connected through the water passing holes 5d in the lower half, forming a communicating vessel. Without considering the density difference between the floating oil layer and water, the liquid levels of the liquid separation tank 5a and the overflow tank 5b should be the same. Since the density of the floating oil layer is slightly less than that of water, the liquid level of the liquid separation tank 5a will be slightly higher than that of the overflow tank 5b. An overflow port 5e is provided at the top of the overflow tank 5b, and water flows out from the overflow port 5e into the water storage tank 5c and is then pumped out from the water storage tank 5c. In this way, the pumping flow rate will not affect the liquid levels of the liquid separation tank 5a and the overflow tank 5b. A baffle with adjustable height can be provided at the overflow port 5e to adjust the liquid level of the overflow port 5e.

[0063] The outlet of the oil-water separator 4 is located in the upper half of the liquid separation tank 5a. Preferably, the upper edge of the outlet of the oil-water separator 4 is flush with the liquid level of the liquid separation tank 5a, or the outlet of the oil-water separator 4 is slightly lower than the liquid level of the liquid separation tank 5a, so as to reduce the floating distance of the oil stain and accelerate the formation of a floating oil layer in the liquid separation tank 5a. The position of the water passing hole 5d is lower than the outlet of the oil-water separator 4 to prevent oil droplets from passing through the water passing hole 5d.

[0064] The water separator 3 is an important part of the oil-water separation system, mainly composed of a barrel body, a water storage chamber, a flow guide plate and a backwash drain port 3a, etc.

[0065] The barrel body is made of carbon steel or stainless steel, with sufficient strength and stiffness to withstand the internal pressure and water flow impact force, ensuring the stable operation of the equipment. A water storage chamber is arranged inside the barrel body. The water storage chamber is used to temporarily store the oil-water mixture transported from the liquid collection tank 1a and provide a stable flow rate for the subsequent oil-water separation treatment. A flow guide plate is arranged inside the water storage chamber, and the shape and angle of the flow guide plate are optimized to ensure that the liquid entering the water storage chamber is evenly distributed and flows into each flow channel 4f of the oil-water separator 4 in a laminar flow state, avoiding the generation of turbulent flow and eddy current, reducing the resuspension of oil droplets, and improving the separation effect.

[0066] The backwash drain port 3a is arranged at the bottom of the water separator 3, used to regularly discharge the impurities and sediments in the water separator 3 to prevent blockage and ensure the normal operation of the water separator 3.

[0067] The spray water tank 7 is used to store the spray water required by the spray tower 1. The outlet of the water distribution tank is connected to the inlet of the spray water tank 7, and the outlet of the spray water tank 7 is connected to the spray heads in the spray tower 1. The spray water tank 7 also has an inlet, which is directly connected to the water source.

[0068] Figure 9The structure of an oil slick collector 6 is shown. The oil slick collector 6 can be selected as an oil slick collecting tank or an oil skimmer. Taking the oil slick collecting tank as an example, baffles are arranged on the side wall of the oil slick collecting tank, and the height of the baffles is adjustable. By adjusting the height of the baffles, the speed at which the oil pollution in the oil slick layer enters the oil slick collecting tank is controlled. The upper edge of the top plate needs to be kept horizontal, and the top height of the baffle is higher than the demarcation layer between the oil slick layer and water in the liquid separation tank 5a.

[0069] The technical solution of the present invention separates oil and water from the sewage (oil-water mixture) generated by the spray tower 1 through structures such as the water separator 3, the oil-water separator 4, and the liquid separation tank 5, and stores the separated purified water in the spray water tank 7 for recycling back to the spray tower 1. Therefore, the technical solution of the present invention not only realizes the recycling of water resources, significantly reduces the consumption of production water, but also reduces wastewater discharge. While improving the environmental protection benefits, it effectively reduces the operating costs of enterprises.

[0070] 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 solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0071] The oil-water separation system of the spray tower 1 of the present invention realizes the efficient separation of the oil-water mixture in the spray tower 1 and the recycling of water resources through the carefully designed components and their coordinated work. This system not only effectively solves the problem of poor oil-water separation effect of the traditional spray tower 1, but also significantly reduces water resource waste and operating costs, has good environmental protection benefits and economic benefits, and is of great significance for promoting the sustainable development of related industries.

[0072] In addition, it should be noted that, in the case of no contradiction, the various specific technical features described in the above specific embodiments can be combined in any suitable way. To avoid unnecessary repetition, the present invention does not separately describe various possible combination methods. In addition, any combination can be made between various different embodiments of the present invention, as long as it does not violate the idea of the present invention, it should also be regarded as the content disclosed by the present invention.

Claims

1. An oil-water separation system, characterized in that: include: A spray tower (1) is provided with a liquid collecting tank (1a) at the bottom thereof, and a liquid outlet of the liquid collecting tank (1a) is connected to an oil-water separator (4); The oil-water separator (4) comprises a cylindrical outer wall (4d), a plurality of partition plates (4e) are arranged inside the outer wall (4d), and a flow channel (4f) extending from an inlet to an outlet is formed between the partition plates (4e); the oil-water separator (4) comprises a horizontal separation section, a twisting and turning section, and a vertical stratification section in sequence from the inlet to the outlet; The partition plate (4e) of the horizontal separation section is arranged horizontally, and the flow channel (4f) is wide in the left-right direction and narrow in the up-down direction; The partition plate (4e) of the twisting steering section is gradually twisted from a horizontal state to a vertical state; The partition plate (4e) of the vertical stratification section is vertically arranged, and the flow channel (4f) is narrow in the left-right direction and wide in the up-down direction; The outlet of the oil-water separator (4) is connected to the liquid separation box (5), and a floating oil collector (6) is arranged at the liquid level on the top of the liquid separation box (5).

2. The oil-water separation system according to claim 1, characterized in that: The liquid outlet of the liquid collecting tank (1a) is connected to a water pump (2), and the water pump (2) is connected to a water distributor (3). A water storage chamber is provided in the water separator (3), and the inlet of the oil-water separator (4) is connected to the water storage tank of the water separator (3).

3. The oil-water separation system according to claim 2, characterized in that: A guide plate is arranged in the water storage chamber, and the liquid in the water divider (3) flows into each flow channel (4f) of the oil-water separator (4) in a laminar flow state through the guide plate.

4. The oil-water separation system according to claim 2, characterized in that: A backwash drain outlet (3a) is provided at the bottom of the water separator (3).

5. The oil-water separation system according to claim 1, characterized in that: The liquid separation box (5) comprises a liquid separation tank (5a), an overflow tank (5b) and a water storage tank (5c); The outlet of the oil-water separator (4) is connected to a liquid separation tank (5a), and the floating oil collector (6) is arranged on the top of the liquid separation tank (5a); the liquid separation tank (5a) is connected to the overflow tank (5b) through a water hole (5d), and the two constitute a communicating vessel; the water hole (5d) is arranged in the lower half of the liquid separation tank (5a); the top of the overflow tank (5b) is provided with an overflow port (5e), ​​and the water flowing out of the overflow port (5e) enters the water storage tank (5c); the water storage tank (5c) is provided with a water outlet of the liquid separation box (5).

6. The oil-water separation system according to claim 5, characterized in that: The oil-water separation system also includes a spray water tank (7), the water outlet of the water separation tank is connected to the inlet of the spray water tank (7), and the outlet of the spray water tank (7) is connected to the spray head in the spray tower (1).

7. The oil-water separation system according to claim 5, characterized in that: The oil-water separator (4) is arranged horizontally, and the outlet of the oil-water separator (4) is located at the upper half of the liquid separation tank (5a); The water passage hole (5d) is located lower than the outlet of the oil-water separator (4).

8. The oil-water separation system according to claim 1, characterized in that: The floating oil collector (6) is a floating oil collection tank or an oil scraper.

9. The oil-water separation system according to claim 1, characterized in that: The surface of the partition plate (4e) on the oil side is made of an oleophilic material.

10. The oil-water separation system according to claim 1, characterized in that: The length of the horizontal separation section is greater than the vertical stratification section.

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