Volumetric flowmeter based on air flotation separation and working method

Abstract

The invention provides a volumetric flowmeter based on air flotation separation and a working method.The volumetric flowmeter comprises a mixing mechanism, a shearing mechanism, a settling chamber and a measuring mechanism, the flowmeter is installed on a petroleum / liquefied natural gas pipeline, the mixing mechanism is provided with a fluid inlet and a gas nozzle, and the gas nozzle is used for gas injection; the mixing mechanism is used for mixing gas and liquid, an outlet of the mixing mechanism is communicated with the shearing mechanism, a shearing turbine is installed in the shearing mechanism and rotates to generate shearing force on the mixed fluid and refine bubbles so that the bubbles can be combined with solid particles, and an outlet of the shearing mechanism is communicated with the settling chamber. Rising separation of solid particle and bubble combination is completed in the settling chamber, an outlet of the settling chamber is communicated with a measuring mechanism, a measuring turbine is installed in the settling chamber and connected with a sensor, and the sensor is used for measuring the rotating speed of the turbine, so that the fluid flow is indirectly obtained. It is ensured that the content of solid particles in fluid entering the measuring turbine is as low as possible.

Description

Technical Field

[0001] The invention belongs to the technical field of flow meters, and in particular relates to a volume flow meter based on air flotation separation and a working method. Background Art

[0002] In the petroleum, chemical and other industrial fields, fluids often contain a certain amount of solid particles. These solid particles can cause a variety of adverse effects on flow meters, such as reducing measurement accuracy and damaging the internal structure of the flow meter. Traditional flow meters usually face reduced accuracy and shortened life when dealing with solid-containing fluids.

[0003] Application number CN201821284649.0, utility model name A flotation machine equipment, disclosed including a flotation pool, a sewage outlet is vertically opened on the left side of the bottom of the flotation pool, the top plate of the flotation pool is covered with a top plate, the upper left part of the flotation pool is fixedly connected with a guide pipe, the left and right sides of the top plate are vertically fixedly connected with push rod motors, and a bubble collecting plate is horizontally placed above the inside of the flotation pool. The utility model is installed by matching the follower pipe and the gas transmission aluminum pipe, and the gas transmission aluminum pipe is matched and installed while the follower pipe rotates, and the gas transmission aluminum pipe can also transmit gas while the follower pipe rotates. The stirring rod on the follower pipe can not only stir the sewage in the flotation pool, but also avoid the problem of particulate matter above the annular aeration pipe adhering to the annular aeration pipe to cause the aeration hole to be blocked.

[0004] A flotation machine device discloses a scheme for wrapping and floating particles in sewage by air flotation. However, when this scheme is used in sewage treatment, due to the different particle sizes of particles, even if there are a large number of bubbles, it is impossible to wrap and float the larger particles. Moreover, the time for the bubbles to wrap and float the particles is a random probability, and it is impossible to remove as many particles as possible. Summary of the invention

[0005] The purpose of the present invention is to solve the defects of the above-mentioned prior art, to provide a volumetric flowmeter and working method based on flotation separation, to solve the influence of solid-containing fluid on the accuracy and life of the flowmeter, especially through the innovative design of sedimentation chamber separation plate to achieve multi-point controllable separation of the combination, and improve the adaptability to fluids with different particle properties.

[0006] The present invention adopts the following technical solution:

[0007] A volume flow meter based on flotation separation includes a mixing mechanism, a shearing mechanism, a sedimentation chamber and a measuring mechanism. The flow meter is installed on an oil / liquefied natural gas pipeline. The mixing mechanism has a fluid inlet and a gas nozzle. The gas nozzle is used to inject gas, and the mixing mechanism is used to mix gas and liquid. The outlet of the mixing mechanism is connected to the shearing mechanism. A shearing turbine is installed in the shearing mechanism. The shearing turbine generates shear force on the mixed fluid through rotation, refines bubbles, and combines bubbles with solid particles. The outlet of the shearing mechanism is connected to the sedimentation chamber. The combination of solid particles and bubbles is separated in the sedimentation chamber. The outlet of the sedimentation chamber is connected to the measuring mechanism. A measuring turbine is installed in the sedimentation chamber. The measuring turbine is connected to a sensor. The sensor is used to measure the turbine speed, thereby indirectly obtaining the fluid flow rate.

[0008] Furthermore, the gas nozzle of the mixing mechanism is connected to a gas injection system, which includes a gas storage tank, a pressure regulator and a gas injection nozzle. The gas storage tank is connected to the gas injection nozzle through a pipeline, and a pressure regulator is installed on the pipeline.

[0009] Furthermore, the separation plate I is installed at the entrance of the sedimentation chamber, and the separation plate I is tightly fitted with the entrance of the sedimentation chamber. The separation plate I adopts a porous plate or a flat plate structure with gaps, and the pores or gaps are 0.5-5 mm.

[0010] Separation plates II, III and IV are distributed at different heights in the settling chamber. Separation plates II, III and IV are flat plate structures, and their surfaces are roughened or coated with a hydrophilic coating. The height difference between separation plates II and III, and between separation plates III and IV is between 10 and 50 cm.

[0011] The separation plate V is an arc-shaped structure, which can intercept solid particles to the maximum extent. The thickness of the separation plate V is 5-15 mm. The separation plate V is fixed to the outlet wall of the settling chamber by welding or bolts, and the two ends of the separation plate V are connected to the guide cover.

[0012] Furthermore, a guide plate is installed on the separation plate I along the flow direction.

[0013] A working method of a volume flow meter based on air flotation separation, comprising:

[0014] Step 1. When the solid-containing fluid enters the flow meter, gas is injected into the fluid through the gas injection system to achieve mixing of gas and liquid in the mixing mechanism.

[0015] Step 2. The mixed fluid enters the shear mechanism, and the shear turbine generates shear force to refine the bubbles and promote the combination of solid particles and bubbles.

[0016] Step 3. The fluid enters the sedimentation chamber, where it undergoes sedimentation separation, and the combination of solid particles and bubbles rises to the surface of the fluid.

[0017] Step 4. The fluid after sedimentation separation continues to drive the measuring turbine in the measuring mechanism to rotate, and the sensor measures the measurement result of the measuring turbine to obtain an accurate measurement value.

[0018] Furthermore, in step 3, separation plate I is used to separate particles with larger particle size, heavier mass and not easily carried up by bubbles, separation plates II, III and IV are used to separate conjugates with smaller density and larger particle size into conjugates with larger density and smaller particle size, and separation plate V intercepts residual solid particles and simultaneously rectifies and buffers the fluid.

[0019] Beneficial effects of the present invention:

[0020] 1. The present invention improves the measurement accuracy. The present invention effectively reduces the influence of solid particles on the flow meter and improves the measurement accuracy through air flotation separation and a special measurement turbine.

[0021] 2. The present invention reduces solid phase damage. The present invention reduces the wear and damage of solid particles to the internal structure of the flow meter through the solid phase degradation mechanism, thereby extending the service life of the flow meter.

[0022] 3. The present invention has strong adaptability. The present invention is suitable for measuring various solid-containing fluids and can be adjusted and optimized according to different fluid properties and flow ranges.

[0023] 4. The present invention can achieve multi-point controllable separation of particles. The unique separation plate design in the settling chamber can effectively separate solid particles and bubble combinations at different positions according to different particle properties, improve separation efficiency and controllability, and ensure the stable operation of the flow meter under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the volume flow meter based on flotation separation of the present invention.

[0025] Figure 2 It is a schematic diagram of the multi-point controllable structure of air flotation separation in the sedimentation chamber of the present invention.

[0026] Figure 3 Schematic diagram of the structure of separation plate I.

[0027] Figure 4 Schematic diagram of the structure of separation plate II, separation plate III and separation plate IV.

[0028] Figure 5 Schematic diagram of the structure of separation plate V.

[0029] Figure 6 Schematic diagram of the gas injection system structure.

[0030] In the figure:

[0031] 1-mixing mechanism, 2-shearing mechanism, 3-sedimentation chamber, 4-measuring mechanism, 5-gas injection system;

[0032] 201- shear turbine;

[0033] 301-separation plate I, 302-guide plate, 303-separation plate II, 304-separation plate III, 305-separation plate IV, 306-separation plate V;

[0034] 401-sensor, 402-measuring turbine;

[0035] 501-gas storage tank, 502-pressure regulator, 503-gas injection nozzle. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are 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.

[0037] Working principle of the present invention:

[0038] 1. Bubble adsorption and carrying: During the mixing, shearing and sedimentation process, bubbles adsorb solid particles and bring them to the surface of the fluid. As the bubbles burst, the solid particles are separated, thus achieving solid phase degradation.

[0039] 2. Continuous shearing action of the shear turbine: The continuous rotation of the shear turbine produces continuous shear force on the fluid, further promoting the combination of solid particles and bubbles, and forcing larger solid particles into smaller particles, which are easier to be adsorbed and carried by bubbles.

[0040] 3. Different treatment methods in the sedimentation chamber according to different particle sizes: Layered separation is achieved based on the difference in the characteristics of solid particles and bubble combinations during the sedimentation process. For combinations with low density and large particle size, due to the relatively large buoyancy they are subjected to, they rise faster and will be intercepted at a higher separation plate (such as separation plate II); while combinations with high density and small particle size rise slower and will be separated at a relatively low position (such as separation plate IV).

[0041] like Figure 1As shown, a volume flowmeter based on flotation separation of the present invention comprises a mixing mechanism 1, a shearing mechanism 2, a settling chamber 3 and a measuring mechanism 4. The flowmeter is installed on an oil / liquefied natural gas pipeline, and the mixing mechanism 1 has a fluid inlet and a gas nozzle, and the gas nozzle is used to inject gas to mix gas and liquid. The outlet of the mixing mechanism is connected to the shearing mechanism 2, and a shearing turbine 201 is installed in the shearing mechanism 2, which generates shear force on the mixed fluid through rotation, and refines bubbles, so that bubbles and solid particles are better combined. The outlet of the shearing mechanism 2 is connected to the settling chamber 3, and the sheared fluid is settled and separated here. The shape and size of the settling chamber 3 are optimized to promote the rising and separation of the combination of solid particles and bubbles. The outlet of the settling chamber 3 is connected to the measuring mechanism 4, and a measuring turbine 402 is installed therein. The measuring turbine 402 is connected to the sensor 401, and the sensor 401 is a high-precision sensor that can accurately measure the rotation speed of the turbine, thereby indirectly obtaining the fluid flow rate. The design of the measuring turbine 402 mainly considers the accurate measurement of the fluid flow rate, and its structure is more precise to ensure the accuracy and stability of the measurement.

[0042] Further, such as Figure 6 As shown, the gas nozzle of the mixing mechanism 1 is connected to the gas injection system 5, and the gas injection system 5 includes a gas storage tank 501, a pressure regulator 502 and a gas injection nozzle 503. The gas storage tank 501 is connected to the gas injection nozzle 503 through a pipeline, and the pressure regulator 502 is installed on the pipeline. The gas storage tank 501 is used to store compressed air, such as air or nitrogen. The pressure regulator 502 can adjust the injection pressure of the gas according to the properties and flow rate of the fluid. The gas injection nozzle 503 is used to inject the compressed gas into the fluid in a small and uniform state to fully mix the gas and the liquid.

[0043] Furthermore, the blade shape and angle of the shear turbine 201 are specially designed to optimize the shearing effect.

[0044] Further, if Figure 3 As shown, the separation plate Ⅰ301 is installed at the entrance of the sedimentation chamber 3. The separation plate Ⅰ301 adopts a porous plate or a flat plate structure with gaps. The size of the pores or gaps is designed to be between 0.5-5 mm according to the total solid particle size distribution of the fluid. The separation plate Ⅰ301 fits tightly with the entrance of the sedimentation chamber 3 and can be fixed by welding, bolting or slot embedding. The separation plate Ⅰ301 mainly intercepts larger solid particles and bubble combinations, and at the same time rectifies the fluid so that the fluid enters the sedimentation chamber 3 evenly and stably. For particles with larger particle size, heavier mass and not easily entrained and raised by bubbles, the separation plate Ⅰ301 plays a role of preliminary screening and blocking to prevent them from directly impacting the subsequent separation structure and ensure the stability of the subsequent separation process.

[0045] like Figure 4As shown, separation plate II 303, separation plate III 304 and separation plate IV 305 are distributed at different heights in the sedimentation chamber 3, and adopt a flat plate structure, and the surface is roughened or coated with a hydrophilic coating to enhance the separation effect. The distance between separation plate II 303 and separation plate III 304, and between separation plate III 304 and separation plate IV 305 is determined to be between 10 and 50 cm according to the solid particle sedimentation characteristics and the desired separation effect. The three separation plates are installed on the inner wall of the sedimentation chamber 3 through a guide rail structure, and the left and right position adjustment and angle adjustment can be achieved, such as Figure 2 Of course, an automatic control system can also be installed to monitor the fluid state in real time with the help of pressure sensors and turbidity sensors, and automatically adjust the positions of the three separation plates.

[0046] The above three separation plates realize the stratified separation of the conjugates with different particle sizes and densities based on the difference in characteristics of the solid particle and bubble conjugates during the sedimentation process. For the conjugates with small density and large particle size, due to their fast rising speed, they will be intercepted at the higher position of the separation plate (such as separation plate II 303), while the conjugates with large density and small particle size will rise slowly and will be separated at a relatively low position (such as separation plate IV 305), so the aperture of separation plate II 303 is larger than that of 305. Separation plate III 304 is located between separation plate II 303 and separation plate IV 305, and its height position enables it to separate the conjugates with a specific particle size and density range, which is between the conjugate characteristics targeted by separation plate II 303 and separation plate IV 305. For example, for some conjugates with intermediate particle size and density, they may reach the position of separation plate III 304 during the rising process, and they may be separated from the main body of the fluid due to the obstruction of separation plate III 304 and their own sedimentation characteristics. In this way, different particle properties can be separated accurately, improving the overall separation efficiency.

[0047] like Figure 5 As shown, the separation plate V306 is an arc-shaped structure, and the thickness of the separation plate V306 is 5-15 mm. It is firmly fixed to the outlet wall of the settling chamber 3 by welding or high-strength bolts, and the two ends of the separation plate V306 are connected to the guide cover to guide the fluid to the center of the measuring turbine 402. The separation plate V306 serves as the last line of defense to protect the measuring turbine 402, intercepts residual solid particles, and at the same time rectifies and buffers the fluid to ensure measurement accuracy and extend the service life of the measuring turbine 402.

[0048] Furthermore, a guide plate 302 is installed on the separation plate I 301 along the flow direction to guide the flow direction of the fluid and enhance the sedimentation effect.

[0049] A working method of a volume flow meter based on air flotation separation, comprising:

[0050] Step 1. When the solid-containing fluid (petroleum / liquefied natural gas) enters the flow meter, gas is injected into the fluid through the gas injection system to achieve mixing of gas and liquid in the mixing mechanism 1.

[0051] Step 2. The mixed fluid enters the shearing mechanism 2, and the shearing turbine 201 generates shearing force on it, refines the bubbles and promotes the combination of solid particles and bubbles.

[0052] Step 3. The fluid enters the sedimentation chamber 3, where sedimentation separation is performed, and the combination of solid particles and bubbles rises to the surface of the fluid.

[0053] Step 4. The fluid after sedimentation separation continues to drive the measuring turbine 402 in the measuring mechanism 4 to rotate, and the sensor 401 measures the measurement result of the measuring turbine 402 to obtain an accurate measurement value.

[0054] Furthermore, the shear force generated by the rotation of the shear turbine in step 2 continuously promotes the solid phase degradation and reduces the influence of the solid particles on the flow meter.

[0055] Furthermore, in step 3, separation plate I 301 is used to separate particles with larger particle size, heavier mass and not easily carried up by bubbles, separation plates II 303, III 304 and IV 305 are used to separate small density and large particle size conjugates to large density and small particle size conjugates, and separation plate V 306 intercepts residual solid particles and rectify and buffer the fluid at the same time. Separation plates at different positions realize multi-point controllable separation according to the difference in properties of solid particles and bubble conjugates, ensuring that the solid particle content in the fluid entering the measuring turbine 402 is as low as possible, thereby improving the overall performance of the flow meter.

[0056] Example

[0057] In a certain petrochemical pipeline, the volumetric flowmeter based on flotation separation of the present invention is installed. First, according to the flow rate and fluid properties of the pipeline, the pressure of the gas injection system 5 and the parameters of the gas injection nozzle 503 are adjusted to ensure that the gas can be fully mixed with the liquid. When the solid-containing fluid enters the flowmeter, it passes through the mixing mechanism 1, the shearing mechanism 2, the sedimentation chamber 3 and the measuring mechanism 4 in sequence. In the sedimentation chamber 3, each separation plate functions according to the design to achieve multi-point controllable separation of solid particles. For example, for crude oil containing sand particles and impurities of different particle sizes, the sand particles with larger particle sizes are partially intercepted by the separation plate I 301 at the entrance, and the impurities with smaller particle sizes are combined with bubbles and separated at different heights of the separation plate II 303, separation plate III 304, and separation plate IV 305 according to the gas density and rising speed. Finally, the very small amount of particles remaining are blocked at the separation plate V 306. In each link, the solid particles and bubbles are continuously combined and separated to achieve solid phase degradation. After a period of operation, the service life of the flowmeter is significantly extended compared with the traditional flowmeter due to the solid phase degradation mechanism.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A volume flow meter based on air flotation separation, characterized in that: The invention comprises a mixing mechanism, a shearing mechanism, a settling chamber and a measuring mechanism. The flow meter is installed on an oil / liquefied natural gas pipeline. The mixing mechanism has a fluid inlet and a gas nozzle. The gas nozzle is used for gas injection. The mixing mechanism is used for mixing gas and liquid. The outlet of the mixing mechanism is connected with the shearing mechanism. A shearing turbine is installed in the shearing mechanism. The shearing turbine generates shear force on the mixed fluid and refines bubbles by rotation, so that the bubbles are combined with solid particles. The outlet of the shearing mechanism is connected with the settling chamber. The combination of solid particles and bubbles is separated by rising in the settling chamber. The outlet of the settling chamber is connected with the measuring mechanism. A measuring turbine is installed in the measuring mechanism. The measuring turbine is connected with a sensor. The sensor is used to measure the turbine speed, thereby indirectly obtaining the fluid flow rate.

2. The flow meter according to claim 1, characterized in that The gas nozzle of the mixing mechanism is connected to the gas injection nozzle of the gas injection system. The gas injection system includes a gas storage tank, a pressure regulator and the gas injection nozzle. The gas storage tank is connected to the gas injection nozzle through a pipeline, and the pressure regulator is installed on the pipeline.

3. The flow meter according to claim 1, characterized in that: Separation plate I is installed at the entrance of the sedimentation chamber. Separation plate I fits tightly with the entrance of the sedimentation chamber. Separation plate I adopts a porous plate or a flat plate structure with gaps; separation plate II, separation plate III and separation plate IV are distributed at different heights in the sedimentation chamber. Separation plate II, separation plate III and separation plate IV adopt a flat plate structure; separation plate V is an arc structure. Separation plate V is fixed to the outlet wall of the sedimentation chamber by welding or bolts, and both ends of separation plate V are connected to the guide cover.

4. The flow meter according to claim 3, characterized in that: The pores or gaps of the separation plate I are between 0.5 and 5 mm.

5. The flow meter according to claim 3, characterized in that: The surfaces of separation plates II, III and IV are roughened or coated with a hydrophilic coating, and the height differences between separation plates II and III, and between separation plates III and IV are all 10-50 cm.

6. The flow meter according to claim 3, characterized in that: The thickness of the separation plate V is 5-15 mm.

7. The flow meter according to claim 1, characterized in that: A guide plate is also installed on the separation plate I along the flow direction.

8. A method for operating a volume flow meter based on air flotation separation, characterized in that: include: Step 1. When the solid-containing fluid enters the flow meter, gas is injected into the fluid through the gas injection system to achieve mixing of gas and liquid in the mixing mechanism; Step 2. The mixed fluid enters the shear mechanism, and the shear turbine generates shear force to refine the bubbles and promote the combination of solid particles and bubbles; Step 3. The fluid enters the sedimentation chamber, where it is subjected to sedimentation separation, and the combination of solid particles and bubbles rises to the surface of the fluid; Step 4. The fluid after sedimentation separation continues to drive the measuring turbine in the measuring mechanism to rotate, and the sensor measures the measurement result of the measuring turbine to obtain an accurate measurement value.

9. The working method according to claim 8, characterized in that: In step 3, separation plate I is used to separate particles with larger particle size, heavier mass and not easily carried up by bubbles, separation plates II, III and IV are used to separate small density and large particle size conjugates into large density and small particle size conjugates, and separation plate V intercepts residual solid particles and rectify and buffer the fluid at the same time.

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