SU1720700A2 - Vortex mixer-homogenizer - Google Patents

Abstract

The invention can be used to produce high-quality various types of emulsions, homogenized solutions, light suspensions. It ensures the operation of the device in systems with increased resistance at the output of the finished product, improving the quality of the mixture. The vortex homogenizer-mixer contains a mixing chamber, in the walls of which two pairs of tangential inlet channels are made. The mixer is equipped with a distributor head having two pairs of guide channels connected to the tangential inlet channels and nozzles installed in the guide channels with a gap in relation to the input of the tangential inlet channels. The gaps are communicated by drilling with fittings input dispersible component. The distributor head is made interchangeable with nozzles of different diameters. The nozzles are mounted for movement along the axis of the guide channels and provided with plugs. The highest productivity of the device was achieved under reduced pressure in the finished product system, with one stream of the dispersible component entering the inlet of tangential channels, and the other stream is in energy exchange and mixed with a rotating sound stream of fluid in the mixing chamber. Each of the streams of the dispersible component has an independent amount of regulation. 1 hp f-ly, 4 ill. cl

Description

The invention can mainly be used in fuel preparation systems for ship diesel engines, boiler units, gas turbines, converted to work using water-fuel emulsions, as well as in compounding fuels, oils, adding additives, preparing suspensions and other processes that require mixing of liquids, and is an improvement devices on a tue. No. 1526798.

The preparation of highly concentrated, high-quality water-fuel emulsions (VTE) to ensure

the most efficient operation of powerful power plants is connected with the need to disperse large volumes of the aqueous phase in the mixers, which is a complex technical task. The grinding of water particles occurs if the forces causing the particle to move in the fuel medium are larger in magnitude than the surface tension forces of the particle being reduced in size. As the particle size decreases, the surface tension forces grow and, if the deformation forces, time, the relative displacement path for the dispersible volume in the fuel

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the medium will appear to be insufficient; large droplets and water in a puff form will appear in the composition of the emulsion, affecting negatively the state of the diesel fuel equipment. The effectiveness of the use of the VTZ is reduced.

Therefore, the devices used to disperse liquids should have a high intensity, a sufficient duration of energy-exchange processes in the interaction of the mixed liquids, energy consumption for the preparation of the emulsion should be minimal.

Considering that the forces in the working bodies of the mixing devices remain constant, an excess of the amount of water supply to the mixers leads to a deterioration in the quality of the emulsion. According to the conditions of work in the fuel systems of consumers, it becomes necessary to switch on dispersants in areas of elevated pressure systems, for example, in the injection section of the fuel supply pump before diesel filters for fine cleaning. Such inclusion of hydrodynamic mixers-homogenizers allows dispersion using standard fuel injection pumps of diesel engines, homogenization of the fuel environment directly in front of filters, reduces energy costs for VTE preparation, and, due to reduced labor intensity for manufacturing, accelerates the use of devices in production.

Closest to the invention is a vortex homogenizer-mixer, used for the homogenization of liquids, the preparation of emulsions, suspensions, contact heat exchange flows, mainly used for the preparation of water-fuel emulsions based on medium and high viscosity motor fuels. The known mixer comprises a mixing chamber, in the walls of which two pairs of profiled swirling inlet ducts for fuel are made. The channels are made tangential and are coupled with recesses made in the walls of the chamber. The mixing chamber is made with a smoothly narrowing section. Water is supplied through a device placed along the axis of the chamber, provided with means for changing the flow area of the radial channels for supplying water. This device is most effective from an autonomous electric pump unit and under the condition of low resistance in the pipeline of the finished product.

An increase in resistance in the discharge pipe behind the device causes an increase in pressure in the mixing chamber, while the flow of dispersible

the component into the mixing chamber becomes difficult, and then stops as the pressure increases. At the same time, the mass-transfer energy of fluids in the tangential inlets of the mixing chamber is not fully utilized.

The purpose of the invention is to improve the performance of the device according to the dispersible amount of the component, increase

5 quality of the mixture and ensuring the operation of the device in systems with increased resistance at the output of the finished product, for example, when working in the fuel system of diesel engines in the process of homogenizing the fuel medium and preparing a water-fuel emulsion.

The goal is achieved by the fact that in the homogenizer-mixer one stream of the dispersible component is fed to

5 the tangential inlet channels enter and mix in the intense turbulent vortices of the dispersing flow as it moves through the channels, and another flow of the dispersible component enters

0 energy exchange and agitated with a rotating vortex sounded flow of fluid in the mixing chamber. During operation of the device, the dispersing liquid

5 is introduced into the tangential inlet channels through guide channels placed in the distributor head with nozzles at the exit of which the velocity of the jet of fluid increases, the cross section is compressed, as a result, a vacuum area is created at the entrance of the tangential channels into which the dispersible component is sucked. jet section and walls

In the 5 channels, a vortex-intensive zone occurs where the component to be dispersed is intensively mixed, drawn into a turbulent flow and, under conditions of high-frequency pulsation of speeds and pressures, is reduced to a finely dispersed state. The frequency of the velocity and pressure pulsations in a turbulent flow is determined by the amplitude of the transverse velocity oscillations located in

5 is functionally dependent on the shape, cross-sectional area, and channel length. At an equal value of the velocities, the intensity of the turbulent whirlwind and, consequently, the exchange of the amount of motion between the flow layers in the channels with a rectangular section pb compared with

round channels increases. Therefore, in order to finely grind the dispersible component in the two-phase flow layers, in the proposed device, the rectangular shape of the tangential channels is selected and their number is increased. The applied stepwise alignment of the nozzles with a rectangular cross section of the tangential inlet channels of the mixing chamber ensures that the dispersing flow separates from the channel walls in the area where the dispersed component is supplied with a significant change in the parameters of the state of the dispersing liquid flow, which increases the reliability of the device. The flow leaving the tangential channels in the mixing chamber acquires rotation, the vortices moving in the sharp rear edges of the channels move in the direction of rotation of the flow, forming a chain of vortices. This process leads to pressure pulsations in the flow and is the primary cause of the occurrence of ultrasonic vibrations and cavitation zones in which the particles of the dispersed component, solid particles of carbenes and carbides are crushed. The centrifugal forces in a rotating flow create the greatest stresses in the plane of the tangential channels, where the diameter of the mixing chamber is maximum, as a result, the pressure of the liquid in the channels increases. In accordance with the formula

P2-P1

p (R% (l) - R a)) 2

where Pi is the pressure of the medium at the exit of the finished product from the mixing chamber;

2 - medium pressure at the level of tangential channels;

p is the density of the medium;

(a-angular flow velocity;

RI is the radius of the outlet of the mixing chamber;

Ra is the radius of the mixing chamber at the level of tangential channels.

The kinetic energy of the flow rotating in the mixing chamber is transformed into potential energy, the pressure in the tangential inlet channels increases, the amount of movement between the fluid layers is intensified, the dispersible substance is mixed in the main flow, the degree of particle size reduction increases. The layers of the liquid under the influence of centrifugal forces in the mixing chamber are compressed, in its center a volume is formed which is not occupied by the liquid, in the form of a rotating paraboloid, from the side of the inner walls of which

5 dispersible component. A significant increase in resistance in the pipeline of the finished product leads to an increase in pressure in the mixing chamber, the volume free from liquid is filled, the input 10 of the dispersible component from the supply device placed in the center of the volume of the mixing chamber becomes difficult and stops at a certain pressure value. Due to the rotating flow in the mixing chamber, an increase in the pressure at the outlet of the finished product does not cause a decrease in the value of the pressure drop at the inlet and outlet of the liquid from the tangential channels, 0 which ensures that the work on grinding the dispersed component is constant. The guide channels with nozzles in the distributor head for the purpose of regulating the overlap process are blocked by plugs, with a part of the tangential channels being removed from the action. In the remaining tangential channels, the dispersion process is intensified. Regulation of the number of simultaneously operating channels is performed depending on the change in the parameters of the fluid state, which allows to optimize the working processes in the device.

5 Supply channels with nozzles can be made interchangeable. Such a constructive solution allows changing the nozzle cross section and adjusting the position of their output edge in the direction of the longitudinal axis 0 of the tangential channels, which also increases the possibility of optimizing the operation of the device in the event of a change in the physical characteristics of the fluids.

Figure 1 shows a vortex homogenic 5 mash-mixer, a longitudinal section; on

figure 2 - section aa in figure 1; on fig.z section bb in figure 2; figure 4 - node on

figure 2.

The homogenizer-mixer contains 0 flanges 1 and 2, by which it is connected to the piping system, a thick-walled cover 3 forming the upper part of the body. In the lower part of the housing 4 there is a mixing chamber 5, made in the shape of a rotating body with a smoothly tapering cross section, which passes into the diffuser 6-. A device 7 is installed along the axis of the mixing chamber to enter the dispersible component supplied to the device through fittings 8 sealed by gaskets 9. Device 7 is made with radial channels 10, having the form of holes or an O-slot, is equipped with a means to change their cross section and ridge the output edge from the camera axis. The medium is made, for example, in the form of a replaceable distribution washer 11 with holes, an intermediate adjusting washer 12 and the wall of the washer 13. The washers are fixed on the pin 14 with a cap nut 15 of the gasket 16. In the walls of the mixing chamber two pairs of inlet profiled channels 17 and 18 are made, directed tangentially to the walls of the mixing chamber. In the walls of the mixing chamber, there are recesses 19 associated with tangential inlet ducts 17 and 18.

The dispersible medium is led to the tangential channels 17 and 18 through guide channels 21 and 22 with nozzles in the distribution head 20. In order to regulate the productivity and quality of mixing, the guide channels 21 are blocked by the plugs included in the device. The dispersible component is introduced into the tangential channels from the annular channel 23 through the gap between the nozzles of the guide channels 21 and 22 and the input edge of the tangential channels 17 and 18. The dispersible component is supplied to the annular channel 23 by drilling from fittings 8. The separation between the distributor head and the outer wall of the mixing chamber is sealed with a ring 24 and a gasket 25.

Homogenizer-mixer works as follows.

The device is connected by flange 1 to the pipeline for supplying the dispersing component, and by flange 2 to the pipeline of the finished product. The flow in the body formed by the lid 3, the dispersing component through the guide channels 21 and 22 with nozzles and tangential inlet channels 17 and 18 is introduced into the mixing chamber 5. Since the working channels relative to the generator of the mixing chamber are tangential, the flow receives rotation, under the action The centrifugal force spreads in the radial direction, while in the center of the chamber a volume with reduced pressure is formed that is not occupied by liquid.

In the mode of operation of a homogenizer-mixer with a reduced pressure (approximately 0.2 MPa) at the outlet of the finished product, the supply of the dispersible component is simultaneously performed from the annular channel

23, to the entrance of the inlet tangential channels 17 and 18 and through the inlet device 7 into the vortex flow rotating in the mixing chamber 5.

Entering into the tangential inlet channels in energy exchange with a high-speed dispersing flow, the dispersing substance is ground.

The second stream of the dispersible component is introduced through the radial channels 10 of the feeder 7 into the high-speed rotating voiced flow of the vortex mixing chamber, where, as a result of the exchange of the amount of ultrasonic vibration, it is crushed and mixed with the dispersing medium. After mixing in the tangential channels and in the mixing chamber, the flow of liquids through the outlet

0, the orifice enters the diffuser 6, where under conditions of turbulent motion, with the pulsation of velocities and pressures, their intensive mixing continues with a gradual increase in the flow volume. In the operation mode, you have a homogenizer-mixer with two pairs of tangential channels with a supply of the dispersible component to the tangential channels and into the mixing chamber;

0 maximum value. With an increase in resistance in the pipeline of the finished product, the pressure of the liquid in the mixing chamber, in the guide channels with nozzles increases, and at a certain

At 5 pressures in the mixing chamber, the injection of the dispersible component into it is stopped.

An increase in the pressure of the dispersing medium in front of the nozzles of the guide channels leads to an additional compression of the flow at the inlet of the tangential channels, which increases the rarefaction, the amount of dispersible component entering the tangential channels also increases. The persistent high pressure drop between the inlet and outlet of the flow from the tangential channels allows them to carry out the process of homogenization of the fuel medium and high efficiency in them.

0 grinding dispersible component. The homogenization of the fuel medium in the tangential channels is realized in a high-speed flow due to the shift of the liquid layers, which leads to an intensive

5 mass transfer, which results in the grinding of water particles, the destruction of solid particles of carbenes and carboids, resin bunches. The fuel medium exiting the tangential channels is treated in the mixing chamber with ultrasound,

causing cavitational phenomena. Such a treatment with a high energy density concentration ensures high fuel homogeneity. The adjustment of the modes of operation of the mixer-homogenizer is carried out by changing the number of simultaneously operating inlet tangential channels blocked by plugs 26 supplied with the device. With a change in the number of channels in operation, mass transfer processes are intensified.

Claims (2)

The replacement of the mixing chamber, carried out depending on the physical properties of the treated liquids, allows influencing the intensity of the mixing processes. With an increase in the outlet of the chamber, the section of the inner walls of the rotating paraboloid grows, which contributes to an increase in quality, allowing a larger volume of liquid to disperse in the device. Claim 1. Vortex homogenizer-mixer according to ed. St. No. 1526798, different By the fact that, in order to ensure the operation of the device in systems with increased resistance at the output of the finished product, improve the quality of the mixture and increase the amount of dispersible component by including additional areas of mass exchange flows, it is equipped with a distribution head having at least two pairs of guide channels, interfaced with tangential inlets and nozzles installed in guide channels with a clearance relative to the input of the tangential inlets, while the gaps are communicated by drilling with the fittings of the dispersible component. 2. Homogenizer-mixer, about tl and h a-yu and and with that, in order to regulate process efficiency, the distribution head is made interchangeable with nozzles of different diameters, the nozzles being mounted for movement along the axis of the guide channels and provided with plugs. one Y /// S / S // J / / SSSZ / jfS // SS77 / S7s o o r- o CM f sss // rs / ws / sssss / ss / s / s // jrss P i t t shyas FIG. 3 II 26 X nineteen Fy