Treatment device for oil-containing emulsified wastewater

Abstract

The invention discloses a treatment device for oil-containing emulsified wastewater, and belongs to the technical field of wastewater treatment.The device comprises a microbubble production module and a flotation module.The main body of the microbubble production module is a microbubble production tank, and the outer side of the microbubble production tank is fixedly connected with a rotational flow-venturi type microbubble generator; the rotational flow-venturi type microbubble generator is connected with the net-shaped turbulent flow structure and arranged on the inner side of the microbubble production groove, an opening is formed in the upper portion of the flotation groove, a hydrophobic film is arranged, and an oil collecting groove is fixedly connected to the hydrophobic film. The device can circularly treat the emulsified oil-containing wastewater, achieves the effects of improving the emulsified oil-containing wastewater treatment efficiency and the oil recovery rate, is convenient to operate, and is energy-saving and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a treatment device for oil-containing emulsified wastewater. Background Art

[0002] Oily wastewater is wastewater containing oily substances discharged during industrial production. If oily wastewater is not recycled, it will cause waste. If it is discharged into rivers, lakes or bays, it will pollute the water body and affect the survival of aquatic organisms. If it is used for agricultural irrigation, it will hinder the growth of crops. Many researchers have studied the treatment of oily wastewater. At present, the main methods for removing oil from oily wastewater are: gravity sedimentation, physical and chemical methods, chemical coagulation, coarse granulation, filtration, flotation, activated carbon adsorption, biological method, and electromagnetic method. In order to save the cost of wastewater treatment and simplify the operation, the US patent No. US3869388A provides a method for water-oil separation: by adding a liquid that is insoluble in oil or water and has a density between oil and water, a separation layer is formed between oil and water. The method has simple equipment and can achieve oil-water separation, but the wastewater treatment efficiency is not high. Designing a device that is simple to operate and can improve the wastewater treatment efficiency is a problem that needs to be solved in the current field. Summary of the invention

[0003] The object of the present invention is to provide a treatment device for oil-containing emulsified wastewater to realize the cyclic treatment of emulsified oil-containing wastewater, reduce energy consumption, and improve the efficiency of treating emulsified oil-containing wastewater.

[0004] In order to solve the above technical problems, the present invention specifically provides the following technical solutions: A treatment device for oil-containing emulsified wastewater comprises a microbubble production module, the main body of the microbubble production module is a microbubble production tank, one end of the microbubble production tank is connected to a swirl-Venturi type microbubble generator, and the other end is connected to the front end of a flotation tank, the top of the flotation tank is open, and an oil collection tank is connected thereon.

[0005] Specifically, the microbubble production tank is equipped with a flow disturbance structure, which is a mesh channel connected to the swirl-Venturi type microbubble generator.

[0006] The present invention introduces emulsion and oily wastewater into a swirl-Venturi type microbubble generator, so that microbubbles are generated in a microbubble production tank, the tiny bubbles are dissolved in the oil droplets, and as a carrier, form a floating body with an overall density less than that of water and float to the water surface, and a flotation tank is used to separate oil, emulsion and water, and an oil collection tank is set to collect the oil, thereby achieving the treatment of oily wastewater. The flow disturbance structure adopts a multi-layer circular filter screen, and the size of the microbubbles is smaller after shearing through the mesh flow disturbance structure, which can increase the contact area between the microbubbles and the oil droplets and thus accelerate the flotation process, thereby improving the efficiency of oily wastewater treatment.

[0007] Specifically, the swirl-Venturi type microbubble generator consists of a swirl chamber and a venturi tube, and the swirl chamber is sequentially connected to the inlet section, the contraction section, the throat and the diffusion section of the venturi tube.

[0008] In the present invention, a vortex is formed after the fluid passes through the vortex chamber, and the vortex is accelerated and spun after passing through the inlet section and the contraction section of the venturi. When the fluid enters the contraction section, the cross-section is reduced and the fluid flow rate increases. According to Bernoulli's principle, the increase in flow rate will lead to a decrease in fluid pressure, resulting in a negative pressure zone. The negative pressure zone will absorb surrounding air or other fluids and mix with the main fluid, and microbubbles are formed under the synergistic effect of various microbubble generation mechanisms such as vortex shear, turbulent pulsation and vortex crushing. The vortex intensity of the vortex liquid reaches the maximum in the throat of the venturi, and then enters the diffusion section, the flow rate slows down, and the pressure gradually recovers to a higher level, forming a gas-liquid two-phase shock wave. Under the action of the shock wave, the microbubbles can further form smaller bubbles.

[0009] Specifically, an air inlet is provided at one end of the cyclone chamber, and the air inlet is connected to an air guide pipe.

[0010] In the present invention, the air guide pipe is arranged on the central axis of the swirl chamber and the venturi tube. Due to the swirl effect, negative pressure is formed in the central area of ​​the swirl. After the gas enters the venturi tube through the air guide pipe, it mixes with the mainstream to form bubbles.

[0011] Specifically, the main body of the vortex chamber is an annular channel with equal cross-sectional area, and a first water inlet and a second water inlet are provided on the side of the vortex chamber. The first water inlet is connected to the circulation guide pipe, and the second water inlet is connected to the first guide pipe.

[0012] Specifically, the first water inlet and the second water inlet are arranged in parallel and opposite directions on both sides of the vortex chamber, the cross-sectional diameter ratio of the first water inlet and the second water inlet is 0.8:1~1:1, and the cross-sectional diameter ratio of the annular channel of the vortex chamber and the second water inlet is 0.8:1~1.25:1.

[0013] The first water inlet introduces the emulsion, and the second water inlet introduces the oily wastewater. The cross-sections of the first water inlet and the second water inlet are both circular and have the same diameter. After the fluid enters the swirl chamber from the guide tubes on both sides, it is restricted by the geometric shape of the swirl chamber to form a swirl. At this time, the emulsion is mixed with the oily wastewater, and the fluid moves in a circular motion while entering the Venturi tube forward. The cross-sectional diameter of the first water inlet is slightly smaller than the cross-sectional diameter of the second water inlet. When the flow rates of the emulsion and the oily wastewater are the same, the flow rate of the oily wastewater is greater than the flow rate of the emulsion, which can save the amount of emulsion. It is worth noting that if the cross-sectional area of ​​the first water inlet and the second water inlet differ too much, it is not conducive to the formation of the swirl and the discharge of the emulsion from the flotation tank into the circulating guide tube. In order to form a stable swirl in the swirl chamber, the cross-sectional diameter of the annular channel of the swirl chamber should be close to the cross-sectional diameters of the first water inlet and the second water inlet.

[0014] Specifically, the end of the flotation tank is connected to the circulation guide pipe, and a section of the circulation guide pipe extends into the flotation tank.

[0015] In the present invention, the circulation guide pipe is placed outside the device, one end of which is connected to the first water inlet of the cyclone chamber, and the other end is connected to the flotation tank. Since the density of water is greater than that of emulsion and greater than that of oil, in the flotation tank, water, emulsion, and oil are arranged from bottom to top. The emulsion can flow out of the circulation guide pipe in the middle of the flotation tank and then enter the cyclone chamber from the first water inlet to achieve recycling, so that the entire device can achieve the effect of cyclically treating emulsified oily wastewater, thereby improving the efficiency of treating emulsified oily wastewater and the oil recovery rate.

[0016] Specifically, a hydrophobic membrane is provided at the upper opening of the flotation tank.

[0017] Specifically, a drainage conduit is provided below the flotation tank.

[0018] The floating oil layer enters the oil collection tank through the hydrophobic membrane, wherein the hydrophobic membrane is an MPP hydrophobic membrane, and the number of openings of the hydrophobic membrane can be set according to specific conditions. The drainage conduit is located below the end of the flotation tank, and the clean water at the bottom of the flotation tank can be discharged through the drainage port.

[0019] The present invention uses a swirl-Venturi type microbubble generator to generate microbubbles to emulsify and treat oily wastewater. The emulsion and oily wastewater pass through a swirl chamber, a venturi tube and a turbulent structure to generate microbubbles. The flotation tank is used to separate oil, emulsion and water, thereby treating the oily wastewater. The present invention can realize the cyclic treatment of emulsified oily wastewater, improve the efficiency of treating emulsified oily wastewater and the oil recovery rate, and is easy to operate, energy-saving and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0021] Figure 1 Schematic diagram of the device described in Example 1 of the present invention.

[0022] Figure 2 It is a cross-sectional view of the device described in Example 1 of the present invention.

[0023] Figure 3 Schematic diagram of a swirl-Venturi type microbubble generator.

[0024] Figure 4 Schematic diagram of swirl formation.

[0025] Figure 5 It is the assembly diagram of oil collection tank and flotation tank.

[0026] Figure 6 Schematic diagram of the spoiler structure in Example 2.

[0027] Explanation of the reference numerals: 1-cyclone-Venturi type microbubble generator; 2-air guide tube; 3-first guide tube; 4-circulation guide tube; 5-disturbance structure; 501-filter screen; 502-blade; 6-microbubble production tank; 7-flotation tank; 8-hydrophobic membrane; 9-drainage duct; 10-oil collection tank; 101-cyclone chamber; 102-inlet section; 103-contraction section; 104-throat; 105-diffusion section; 106-air inlet; 107-first water inlet; 108-second water inlet. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The following first describes the concepts involved in the present application in conjunction with the accompanying drawings. It should be noted that the following description of each concept is only to make the content of the present application easier to understand, and does not limit the scope of protection of the present application; at the same time, the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail with reference to the accompanying drawings and in conjunction with the embodiments.

[0030] Embodiment 1 like Figure 1~Figure 5 As shown, the present invention provides a treatment device for oil-containing emulsified wastewater, including a microbubble production module, the main body of the microbubble production module is a microbubble production tank 6, one end of the microbubble production tank 6 is connected to a swirl-Venturi type microbubble generator 1, and the other end is connected to the front end of a flotation tank 7, the flotation tank 7 has an opening at the top, and an oil collection tank 10 is connected thereto.

[0031] Specifically, the microbubble production tank 6 is internally provided with a flow disturbance structure 5 , and the flow disturbance structure 5 is a mesh channel connected to the swirl-Venturi type microbubble generator 1 .

[0032] Specifically, the swirl-Venturi type microbubble generator 1 is composed of a swirl chamber 101 and a venturi tube, and the swirl chamber 101 is sequentially connected to an inlet section 102, a contraction section 103, a throat 104 and a diffusion section 105 of the venturi tube.

[0033] The present invention introduces emulsion and oily wastewater into a swirl-venturi type microbubble generator 1, so that microbubbles are generated in a microbubble production tank 6, and the tiny bubbles are dissolved in the oil droplets and used as a carrier to form a floating body with an overall density less than that of water and float to the water surface, and a flotation tank 7 is used to separate oil, emulsion and water, and an oil collection tank 10 is set to collect the oil, thereby achieving the treatment of oily wastewater. The spoiler structure 5 adopts a multi-layer circular filter screen, and the size of the microbubbles is smaller after shearing through the mesh spoiler structure 5, which can increase the contact area between the microbubbles and the oil droplets and thus accelerate the flotation process, thereby improving the treatment efficiency of oily wastewater.

[0034] Specifically, one end of the cyclone chamber 101 is provided with an air inlet 106, and the air inlet 106 is connected to the air guide pipe 2. In the present invention, the air guide pipe is arranged on the central axis of the cyclone chamber 101 and the venturi tube, and negative pressure is formed in the central area of ​​the cyclone due to the cyclone action, and the gas enters the venturi tube through the air guide pipe 2 and mixes with the mainstream to form bubbles.

[0035] Specifically, the main body of the vortex chamber 101 is an annular channel with equal cross-sectional area, and a first water inlet 107 and a second water inlet 108 are provided on the side of the vortex chamber 101. The first water inlet 107 is connected to the circulation guide pipe 4, and the second water inlet 108 is connected to the first guide pipe 3.

[0036] Specifically, the first water inlet 107 and the second water inlet 108 are arranged in parallel and opposite directions on both sides of the vortex chamber 101, the cross-sectional diameter ratio of the first water inlet 107 and the second water inlet 108 is 0.8:1~1:1, and the cross-sectional diameter ratio of the annular channel of the vortex chamber 101 and the second water inlet 108 is 0.8:1~1.25:1.

[0037] The first water inlet 107 is used to introduce the emulsion, and the second water inlet 108 is used to introduce the oily wastewater. The cross-sections of the first water inlet 107 and the second water inlet 108 are both circular and have the same diameter. After the fluid enters the cyclone chamber 101 from the guide tubes on both sides, it is restricted by the geometric shape of the cyclone chamber 101 to form a cyclone. At this time, the emulsion is mixed with the oily wastewater, and the fluid moves in a circular motion while entering the venturi tube forward. The cross-sectional diameter of the first water inlet 107 is slightly smaller than the cross-sectional diameter of the second water inlet 108. When the flow rates of the emulsion and the oily wastewater are the same, the flow rate of the oily wastewater is greater than the flow rate of the emulsion, which can save the amount of emulsion. It is worth noting that if the cross-sectional area of ​​the first water inlet 107 and the second water inlet 108 differ too much, it is not conducive to the formation of the cyclone and the discharge of the emulsion from the flotation tank 7 into the circulation guide tube 4. In order to form a stable vortex in the vortex chamber 101 , the cross-sectional diameter of the annular channel of the vortex chamber 101 should be close to the cross-sectional diameters of the first water inlet 107 and the second water inlet 108 .

[0038] Specifically, the end of the flotation tank 7 is connected to the circulation guide pipe 4 , and a section of the circulation guide pipe 4 extends into the flotation tank 7 .

[0039] In the present invention, the circulation guide pipe 4 is placed outside the device, one end of which is connected to the first water inlet 107 of the cyclone chamber 101, and the other end is connected to the flotation tank 7. Since the density of water is greater than that of emulsion and greater than that of oil, the flotation tank 7 contains water, emulsion, and oil from bottom to top. The emulsion can flow out of the circulation guide pipe 4 in the middle of the flotation tank 7 and then enter the cyclone chamber 101 from the first water inlet 107 to achieve recycling, so that the entire device can achieve the effect of cyclically treating the emulsified oily wastewater, thereby improving the efficiency of treating the emulsified oily wastewater and the oil recovery rate.

[0040] Specifically, a hydrophobic membrane 8 is provided at the upper opening of the flotation tank 7, and a drainage conduit 9 is provided below the flotation tank 7. The floating oil layer enters the oil collection tank 10 through the hydrophobic membrane 8, wherein the hydrophobic membrane 8 is an MPP hydrophobic membrane, and the number of hydrophobic membranes and openings can be set according to specific circumstances. The drainage conduit 9 is located below the end of the flotation tank 7, and the clean water at the bottom of the flotation tank 7 can be discharged through the drainage port.

[0041] The present invention can realize the cyclic treatment of emulsified oily wastewater, thereby achieving the effect of improving the treatment efficiency of the emulsified oily wastewater and the oil recovery rate, and is easy to operate, energy-saving and environmentally friendly.

[0042] Embodiment 2 Based on the further optimization of the spoiler structure in the first embodiment: like Figure 6As shown, the flow disturbance structure 5 is a semicircular filter 501 staggered between layers, and the semicircular filter 501 is at least two. A cylinder is arranged on the periphery of the filter, and a blade 502 is connected to the inner wall of the cylinder. The blade 502 can rotate under the action of the swirl, thereby driving the cylinder and the filter 501 to rotate, and the kinetic energy of the water flow is converted into the kinetic energy of the rotation of the blade 502 and the cylinder, the water flow speed is slowed down, and the oily wastewater reacts fully with the emulsion. At the same time, the fluid flowing through the flow disturbance structure 5 collides, rubs and cavities due to the rotation of the cylinder and the filter 501, and is sheared by the mesh of the semicircular filter 501, and microbubbles of smaller size are generated in the microbubble production tank 6. In addition, the impurity adhesion of the filter can be reduced by rotating, and the impurity particles will move to the periphery of the filter under the action of centrifugal force, thereby preventing the impurities from accumulating in the central area of ​​the filter and affecting the passage of microbubbles.

[0043] The interlayer transition angle of the semicircular filter 501 described in this embodiment is 90°~180°, and the interlayer gap is one-half to one thickness of the filter 501. The filter 501 is arranged in such a staggered manner to prevent the problem of mesh clogging when filtering impurities, and at the same time, the microbubbles and the grid can be sheared to produce more and smaller microbubbles, thereby improving the treatment efficiency of emulsified oily wastewater.

[0044] Embodiment 3 The principle of swirl-Venturi type microbubble generator: The swirl-Venturi type microbubble generator 1 is composed of a swirl chamber 101 and a venturi tube, wherein the swirl chamber 101 is sequentially connected to an inlet section 102, a contraction section 103, a throat 104 and a diffusion section 105 of the venturi tube.

[0045] In the present invention, the fluid forms a vortex after passing through the vortex chamber 101, and the vortex is accelerated and spun after passing through the inlet section 102 and the contraction section 103 of the venturi. When the fluid enters the contraction section 103, the fluid flow rate increases due to the reduction in cross-section. According to the Bernoulli principle, the increase in flow rate will lead to a decrease in fluid pressure, resulting in a negative pressure area. The negative pressure area will absorb the surrounding air or other fluids and mix with the main fluid. Microbubbles are formed under the synergistic effect of various microbubble generation mechanisms such as vortex shear, turbulent pulsation and vortex crushing. The vortex intensity of the vortex liquid reaches the maximum when it is in the throat 104 of the venturi, and then enters the diffusion section 105, the flow rate slows down, and the pressure gradually returns to a higher level, forming a gas-liquid two-phase shock wave. Under the action of the shock wave, the microbubbles can further form smaller bubbles.

[0046] It should be noted that the terms used in this application are only for describing specific embodiments, rather than limiting the scope of this application. As shown in the specification of this application, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of further restrictions, the elements defined by the statement "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0047] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any form. Any technical personnel in this field may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention. This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the invention to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A treatment device for oily emulsified wastewater, comprising a microbubble production module, characterized in that: The main body of the microbubble production module is a microbubble production tank (6), one end of the microbubble production tank (6) is connected to the swirl-Venturi type microbubble generator (1), and the other end is connected to the front end of the flotation tank (7), and the flotation tank (7) has an opening at the top, and an oil collection tank (10) is connected thereto.

2. The device for treating oily emulsified wastewater according to claim 1, characterized in that: The microbubble production tank (6) is provided with a flow disturbance structure (5) therein, and the flow disturbance structure (5) is a mesh channel connected to the swirl-Venturi type microbubble generator (1).

3. The device for treating oily emulsified wastewater according to claim 1, characterized in that: The swirl-Venturi type microbubble generator (1) is composed of a swirl chamber (101) and a venturi tube, wherein the swirl chamber (101) is sequentially connected to an inlet section (102), a contraction section (103), a throat (104) and a diffusion section (105) of the venturi tube.

4. The device for treating oily emulsified wastewater according to claim 3, characterized in that: An air inlet (106) is provided at one end of the cyclone chamber (101), and the air inlet (106) is connected to the air guide pipe (2).

5. The device for treating oily emulsified wastewater according to claim 3, characterized in that: The main body of the vortex chamber (101) is an annular channel with a constant cross-sectional area. A first water inlet (107) and a second water inlet (108) are provided on the side of the vortex chamber (101). The first water inlet (107) is connected to the circulation guide pipe (4), and the second water inlet (108) is connected to the first guide pipe (3).

6. The device for treating oily emulsified wastewater according to claim 5, characterized in that: The first water inlet (107) and the second water inlet (108) are arranged in parallel and opposite directions on both sides of the vortex chamber (101); the cross-sectional diameter ratio of the first water inlet (107) and the second water inlet (108) is 0.8:1-1:1; and the cross-sectional diameter ratio of the annular channel of the vortex chamber (101) and the second water inlet (108) is 0.8:1-1.25:

1.

7. The device for treating oily emulsified wastewater according to claim 1, characterized in that: The end of the flotation tank (7) is connected to the circulation guide pipe (4), and a section of the circulation guide pipe (4) extends into the flotation tank (7).

8. The device for treating oily emulsified wastewater according to claim 1, characterized in that: A hydrophobic membrane (8) is provided at the upper opening of the flotation tank (7).

9. The device for treating oily emulsified wastewater according to claim 1, characterized in that: A drainage conduit (9) is provided below the flotation tank (7).

Images