CN114749138A

CN114749138A - Method for treating mixed fluid by using multistage hydrodynamic cavitation device

Info

Publication number: CN114749138A
Application number: CN202210323993.0A
Authority: CN
Inventors: 孙震; 薛冬梅; 顾时雨; 王星浩
Original assignee: China India Hengsheng Beijing Trading Co ltd
Current assignee: China India Hengsheng Beijing Trading Co ltd
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2022-07-15

Abstract

The present invention provides a method of treating a mixed fluid using a multi-stage hydrodynamic cavitation device, the system comprising a cylindrical device having a flow channel with multiple nozzles, a helical conduit, a vortex generator and an atomizing cone arranged sequentially therein to direct cavitation characteristics in the fluid mixture. The sequence elements are intended to direct and eliminate cavitation features in a multi-stage process.

Description

Method for treating mixed fluid by using multistage hydrodynamic cavitation device

Technical Field

The present invention relates to a method of treating mixed fluids using a multi-stage hydrodynamic cavitation device, and in particular, to the modification of complex fluids composed of many individual compounds and the use of cavity implosion energy to improve the homogeneity, viscosity and/or other physical properties of the fluid by changing its chemical composition and converting the compounds to obtain an upgraded, more useful product.

Background

The pressure rise, temperature rise and vigorous mixing produced by acoustic or hydrodynamic cavitation initiate and accelerate many reaction processes. Enhancement of reactions and processes by energy released upon collapse of cavities in fluids has found application in a number of technologies for upgrading, mixing, pumping and accelerating chemical transformations. While extreme pressures or large amounts of heat may cause damage to the partially counterfeit, more expensive machinery, the results are often very beneficial through controlled use.

Cavitation can be produced in many different ways, for example, hydrodynamic, acoustic, laser-induced or by direct injection of steam into a super-cooled fluid, which produces collapse conditions similar to hydrodynamic and acoustic cavitation. Direct steam jet cavitation is coupled with acoustic cavitation with up to 16 times higher efficiency than acoustic cavitation alone. The formation of bubbles is evident when the temperature of the fluid is close to the boiling point, and if the fluid is irradiated with ultrasonic waves or treated in a hydrodynamic cavitation reactor with appropriate velocity, cavitation bubbles will form at concentrations of hundreds per milliliter. Increasing the pressure can inhibit their formation. The bubbles occupy the space normally occupied by the fluid, which impedes flow and increases pressure. If the cavitation bubbles are relocated to a low velocity high pressure zone (as opposed to the bernoulli principle), they will implode-8-10-6 s in 10 minutes-implosion is accompanied by a sharp local rise in pressure and temperature, up to 1000 atm and 5000 ℃. This pressure and temperature increase results in the generation of local jets with a velocity of 100 m/s and higher.

The collapse of the cavity is accompanied by the release of shock waves, strong shear forces and large amounts of energy that activate atoms, molecules and radicals within the gas phase bubbles, as well as in the surrounding fluid. The energy released with the collapse can initiate chemical reactions and processes, or be dissipated into the surrounding fluid. In many cases, implosions are emission-free. Ultraviolet or visible light is then typically emitted, which may initiate photochemical reactions and generate free radicals, and one disadvantage of the ultra high pressure is the generation of extremely high heat, which can be detrimental to product quality and safety if overheated.

Disclosure of Invention

The present invention provides a method and apparatus for generating multi-stage cavitation in a fluid stream in at least three successive cavitation chambers. This object is achieved by designing a multistage cavitation device which is intended for rapid modification of complex fluids. According to the invention, the method comprises feeding fluid in a flow-through hydrodynamic multi-chamber cavitation device using a controlled inlet pressure maintained by a pump and applying selected reagents and conditions.

The present invention relates to a method of treating a fluid mixture in a multi-stage hydrodynamic cavitation device. The method begins with providing a flow path through a hydrodynamic cavitation device. Next, the fluid mixture is pumped through a multi-nozzle having a plurality of channels. The multiple nozzles create cavitation features in the jet mixture. The fluid mixture then passes through a plurality of spiral guides arranged in the working chamber, the spiral guide also creating cavitation features in the fluid mixture, which is subsequently conveyed on a plurality of deflectors in a vortex chamber, the deflectors and vortex chamber creating cavitation features in the jet mixture, and finally, introducing the jet mixture into an atomizing cone having an increased cross-sectional area where the jet mixture loses all of the cavitation features.

The working chamber is defined by the outer wall of the pilot cone and the inner wall of the converging cone. The pilot cone and the converging cone are coaxially arranged along the flow path such that the working chambers are along facing inner and outer walls of the respective cones. The helical guide is arranged around the outer wall of the guide cone and the pitch decreases as the diameter of the working chamber decreases, the helical guide extending from the multi-nozzle to the top of the guide cone.

The multi-nozzle preferably comprises four channels. Each channel has an abrupt contraction and expansion along the flow path. The channel may be a venturi-type channel, having a conical inlet with a circular profile, a cylindrical throat, and a conical outlet, which may treat the fluid mixture multiple times, which may be achieved by multiple channels of a single multi-stage hydrodynamic cavitation device or multiple multi-stage hydrodynamic cavitation device channels arranged in series.

A multi-stage hydrodynamic cavitation device for treating a fluid mixture includes a cylindrical housing having a flow passage therethrough and an inlet cone disposed in an inlet to the flow passage, with a multi-nozzle located in the flow passage behind the inlet cone. The multi-nozzle has a plurality of channels arranged around a perimeter ring of the multi-nozzle. The flow path behind the multiple nozzles has an annular tapered working chamber of progressively decreasing diameter, and a plurality of helical conduits are disposed within the working chamber and extend from passages in the multiple nozzles through the working chamber.

The vortex generator is connected to the working chamber along a flow path. The vortex generator includes a front plate, a rear plate, and a cylinder disposed therebetween. The front and rear discs include curved baffles from the central bore to an annular gap around the cylinder block, and an atomizing cone follows the swirl chamber along a flow path.

Drawings

FIG. 1 is a preferred embodiment of the multi-stage cavitation device of the present invention

Fig. 2 is a cross-sectional view of the multi-stage cavitation device shown along line 2-2 of fig. 1.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the present invention provides an embodiment of a system comprising a housing defining a substantially cylindrical exterior, a fluid inlet in the housing, a working chamber, a fluid outlet in the working chamber for withdrawing fluid from the chamber, an outlet from the vortex chamber, and an atomizing cone coaxially aligned with the upstream chamber. The fluid inlet is positioned to introduce fluid into an upstream multi-nozzle housing channel having abrupt contraction and expansion characteristics. The working chamber is the key part of the system and is in the shape of a convergent cone. The working chamber is provided with a flow guide element which is a place where the first cavitation effect occurs. The fluid outlet accelerates and directs the fluid into the vortex chamber where a second cavitation effect occurs. The bubble-rich stream exiting the atomizer is subjected to a third cavitation process.

Figures 1 and 2 consist of a cylindrical body 10, preferably made of metal, an inlet pipe 12 and an outlet pipe 14. An inlet cone 16 is located in front of a multi-nozzle 18 along the flow path. A guide cone 20 is located behind the nozzle 18 and has a helical guide 22. The multi-nozzle 18 is in the form of a disc with a peripheral ring 19 and has four channels 24, these channels 24 having the characteristic of lateral sudden contractions and expansions. The number of spiral ducts 22 is equal to the number of channels 24 in the multi-nozzle 18, the channels 24 being evenly distributed over the entire surface area of the multi-nozzle 18 and flowing directly along the working chamber 26. Behind the converging cone 28 is a vortex chamber or generator 29 consisting of circular discs 30, 32, a curved baffle 34 and a coaxially aligned central bore 36, an annular gap 38 being located between the front and rear discs 30, 32 and surrounding a cylindrical body 40 slightly smaller in diameter than the vortex chamber 29 which blocks the direct path of the jet from the central bore 36 in the front disc 30. The curved deflector 34 rises relative to the valve discs 30, 32 so as to extend to the cylindrical valve body 40.

The baffle 34 forms a plurality of tortuous flow paths from a central aperture 36 in the front disk 30 to an annular gap 38 of a vortex generator 39. A similar path is formed from the annular gap 38 of the vortex chamber 39 to the central hole 36 in the rear disc 32 on the back of the cylindrical body 40. The diameters of the central bore 36, the outlet 42 of the converging cone 28 and the inlet 44 of the atomizing cone 46 (located along the flow path behind the vortex generator 29) are all the same.

The cavitation device 9 of the present invention may be made of many materials, but there are certain criteria for the choice of material. The materials should be simple to manufacture and braze, capable of withstanding high pressures and temperatures, and have high corrosion resistance, thereby allowing the system to be continuously and repeatedly operated in a variety of fluids.

Claims

1. A method of treating a mixed fluid using a multi-stage hydrodynamic cavitation device, the method comprising: comprises a flow passage passing through the hydrodynamic cavitation device; pumping the fluid mixture through a multi-nozzle having a plurality of channels, wherein the multi-nozzle creates cavitation features in the fluid mixture; passing the fluid mixture through a plurality of spiral conduits disposed in a working chamber, wherein the spiral conduits create cavitation features in the fluid mixture.

2. The method of treating a mixed fluid using a multi-stage hydrodynamic cavitation device of claim 1 further comprising conveying the fluid mixture over a plurality of baffles in a vortex chamber, wherein the baffles and vortex chamber create cavitation features in the fluid mixture, and introducing the fluid mixture into an atomizing cone having an increased cross-sectional area, wherein the fluid mixture loses all cavitation features.

3. The method of claim 1, wherein the working chamber is defined by an outer wall of a guide cone and an inner wall of a converging cone, the converging cone being coaxially arranged with the guide cone along the flow passage such that the working chamber has a reduced diameter along the flow passage.

4. A method of treating a mixed fluid using a multi-stage hydrodynamic cavitation device as claimed in claim 3 wherein the helical guide is disposed about the outer wall of the guide cone and has a decreasing pitch following a decreasing diameter towards the peak of the guide cone.

5. The method of claim 1, wherein the multi-nozzle comprises four channels having sudden contraction and expansion characteristics along the channel.

6. The method of claim 1, wherein the multi-nozzle comprises four channels, the channels being venturi-type channels comprising a conical inlet with a circular profile, a cylindrical throat, and a conical outlet.

7. A method of treating a mixed fluid using a multi-stage hydrodynamic cavitation device of claim 1 further comprising the step of treating the fluid mixture multiple times through multiple channels of the multi-stage hydrodynamic cavitation device or through multiple channels of the multi-stage hydrodynamic cavitation device arranged in series.

8. A device using multi-stage hydrodynamic cavitation in accordance with claim 7 wherein the multi-nozzle has four channels, each of which is a venturi-type channel consisting of a conical inlet with a circular profile, a cylindrical throat and a conical outlet.