SU1729601A1 - Centrifugal separator - Google Patents

Abstract

The invention relates to devices for separation under the action of centrifugal force flows with components of different densities and can be used in the chemical and other industries. The goal is to increase productivity by increasing the separation factor. The centrifugal separator consists of a vertical cylindrical body 1, a hollow rotor 2 with an opening 3, a cover 4, blades 5 with slotted channels, gaskets 6, a ring 7. Under the blades 5 there is a fitting 8 for supplying the flow to be separated, and above them in the cover 4 - choke 9 for lower flow collection. A fitting 10 with a flange 11 is connected under the opening 3. It is connected to the tube 12. A fitting 13 for removing sediment is placed on the housing 1. The separated flow of aerosols is fed into the housing 1 through the fitting 8, and through the fitting 10 - washing liquid that goes through the tube 12 to the inner surface of the rotor 2, through the channels in the blade x 5, flows down and is thrown onto the inner surface of the housing 1. The stream together with the washing liquid is removed through the nozzle 13, and the purified gas through the nozzle 9. 7 Il. (Ls

Description

The invention relates to the chemical, microbiological, food and other sectors of the industry and is intended for separation under the action of centrifugal force flows with components of different densities.

The purpose of the invention is to increase productivity by significantly increasing the separation factor.

This goal is achieved by the fact that in a centrifugal separator that includes a vertical cylindrical body, a hollow rotor with a bottom opening and blades, a lid, a drive, technological fittings, blades are made in the form of plates with slit-like channels connected to the rotor cavity and open the peripheral part of the front radial edges and are mounted on the rotor perpendicular to its axis, on the bottom of the rotor under the blades there is a fitting for supplying the separated flow, and under the rotor opening there is a fitting for otok with higher density, which is connected with the tube tangentially curved about the inner surface of the cover over rotora.na blades located nozzle for discharging a flow having a lower density and on the housing is located at the bottom of the socket to remove the precipitate.

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In order to ensure the separation of aerosols, the slit-like channels of the plates can also be opened from the side of the peripheral edges and in this case, a fitting for supplying the washing liquid, which is connected to a tube tangentially bent around the inner surface of the rotor, is located under the rotor hole.

1 shows a centrifugal separator, a general view, a section; figure 2 - section A-A in figure 1; fig.Z - node I in figure 1; figure 4 - section bb in fig.Z; Fig. 5 shows the design of blades for aerosol separation; figure 6 - section bb In figure 5; figure 7 - scheme of hydrodynamics flows.

The centrifugal separator consists of a vertical cylindrical body 1 in which a hollow rotor 2 with a lower bore 3 is located. The rotor shaft 2 is fixed in the bearing supports of the cover 4 and connected to a rotary drive (not shown). On the walls of the rotor there are vertical wedge-shaped grooves in which the blades 5 with slit-like channels are inserted. The blades 5 and gaskets b between form a connection with the rotor 2 in the form of a dovetail. The sets of blades 5 and gaskets 6 are pressed against the base of the rotor 2 by means of a ring 7 fixed to the rotor 2 by pins.

On the bottom of the rotor of the housing 1, under the blades 5, there is a nozzle 8 for feeding the separated flow, and on the cover 4 above the blades 5 there is a nozzle 9 for selecting the flow with a lower density. A fitting 10 is located on the bottom of the housing 1 below the rotor hole 3 eccentrically relative to the rotor axis, which is pressed to the bottom with the help of a flange 11 rotatably about its axis with the fastener released, the fitting 10 is connected to the tube 12, which is shown in Fig. 2 , tangentially bent around the inner surface of the rotor in the opposite direction of its rotation. The fitting 10 is intended for flow selection with a higher density.

Figs 2, 3, 4 show that the slit-like channels of the blades 5 are connected to the cavity of the rotor 2 and are open from the side of the peripheral part of the leading edges.

A fitting 13 is located on housing 1 at the bottom to remove sediment.

A variant of the design of a centrifugal separator intended for the separation of aerosols is reflected in FIG. 1.5, 6 and differs from the previous one in that the slit-like channels of the blades 5 are also open from the peripheral edges and are grooves on the front radial edges.

The edges, the tubes 12 (Fig. 5) are tangentially bent around the inner surface of the rotor in the direction of its rotation, and the nozzle 10 is intended to supply the washing fluid.

The centrifugal separator in the separation of particles suspended in a liquid droplet with a greater than liquid density of colloidal particles of heavy ions, molecules (Fig. 1, 2, 3, 4) works as follows. The rotor drive 2 is turned on and a separated flow of fluid is fed through the fitting 8. As a result of the friction of the rotor blade 5 and the dynamic effect of the air vortex arising at the outer surface of the rotor, a layer of liquid at the inner wall of the housing 1 is rotated slowly, mixed and forms a liquid cylinder separated by an air layer from the outer surface of the rotor 2. The thickness of the liquid cylinder is determined The location of the nozzle 9 for the selection of a lighter fraction of the separated flow. The open portions of the channels in the blade x 5 are completely immersed in the fluid layer. The rotation speed of the rotor 2 is selected so that the rotation speed of the liquid ring does not exceed 10% of the rotation speed of the rotor. In this case, the speed of interaction of the blades 5 with the fluid is determined by the peripheral speed of rotation of the rotor w g, where r is the average distance from the axis of the rotor to the open channel section in the blade 5.

An increase in the separation factor is achieved when the front edge of the blade 5 (fig. 7) interacts with the open slit channel 2 and the oncoming flow of the medium.

When the rotor with blades rotates, the relative speed of the oncoming flow of the dropping liquid with partial immersion of the blades in the liquid reaches W 50 m / s, and in the gaseous medium W 200 m / s without a noticeable increase in energy costs. (The pressure on the front edge of the blade is not more than 1 MPa). When the blade thickness d - 1 mm, the curvature of the streamlines at the edge is characterized by a value of 5 mm. At a speed of W 50 m / s, the centrifugal acceleration a W2 / R 502/0, 5-U6 m / s, and the separation factor

To the a / d "500000.

Accordingly, when the blade interacts with the gas flow at a relative speed of W 200 m / s

To 4 000 000.

Since the action of centrifugal forces is manifested only in the boundary layer several tens of micrometers thick in front of the blade edge, the speed of selection of the sorted flow into the channel of the blade must correspond exactly to the speed of separation of the flows in this boundary layer.

The content of the heavy fraction in the separated flow Xk will increase compared with the initial X according to

Hk X (1 + We / Wo),

where We- W) rflevvc R18 /

Wc — deposition rate, m / s;

d4 — diameter of deposited particles, m;

RA - particle density, kg / m3;

PC is medium density, mg / m3;

/ g is the medium viscosity, N s / m2,

On the basis of the practically achievable values of the separation factor K a / g, it is possible to estimate the critical size of the particles, which are really distinguished in the field of action of centrifugal forces.

With the thickness of the blades (5 1 mm and speed W 50 m / s K 0,5 0,5 10e.

It is technically possible to reduce the thickness of the blades to 0.1 mm and increase the speed to 100 m / s. In this case, we obtain the value of K 10, which is theoretically unattainable in the known structures of centrifugal separators.

The critical particle size released by centrifugation is determined from the ratio

d4K 2 VKG1p (U / U4).

4/3 - p 1/2 (PA - / Oc) and where K is a constant Boltzmann, 1.38 x kg / s2 ° K;

V is the volume of the liquid phase, m3;

V4 — solid phase volume, m;

and - centrifugal acceleration, m / s2.

For the values of 1100 kg / m3, / os 1000 kg / m3, and 5-10 m / s2 we obtain d4K 4 nm. For a value of 108 m / s2 d4K 0.4 nm, which corresponds to the size of large ions in solutions and is a prerequisite for the possibility of their separation in the separator.

At the front edges of the blades 5, as shown in Fig. 7, the separation of more dense particles occurs when the separation factor is

TO

gR

As a result of impact on the front edge of the blade 5 dynamic pressure

liquid flow with an increased concentration of separated particles flows through the channels of the blades 5 into the cavity of the rotor 2 and is distributed on its inner surface in the form of a thin layer. The thickness of this layer in the equilibrium state depends on the value of the DDA and the length of the blades in the radial direction.

To ensure fluid extraction with separated particles through the nozzle 10 at a given flow rate or pressure drop, at the entrance to the channels of the blades 5, the fastening of the flange 11 is loosened and the nozzle 10 with the tube 12 is rotated with this

Thus, the end of the tube 12 touches the surface of the liquid layer for a given thickness. In this position, the fitting 12 is fastened.

In case of getting into the input stream

coarse particles are removed through fitting 13.

The centrifugal separator in the separation of a mixture of gases of different densities works the same way as in the separation of liquids,

Only the adjustment of the flow rate of the heavier fraction of the stream to be separated out through the nozzle 10 is carried out on the sampling line connected to this nozzle. It is also required to reduce the gap between

rotor 2 and the bottom of the housing 1 or install a seal.

Centrifugal separator in the separation of aerosols (Fig. 1,5,6) works as follows.

The rotor drive 2 is turned on and a separable flow of aerosol is fed through the fitting 8. Through the nozzle 10, a washing liquid is supplied, which through the tube 12 flows to the inner surface of the rotor, is distributed under the action of centrifugal forces through it in the form of a thin layer and flows through channels into the blade x 5 and is thrown onto the inner surface of the housing 1.

Instead of a bent tube 12 in the cavity of the drum can be placed nozzle.

The aerosol flow interacts with the leading edges of the blades 5, which

are grooves with flushing fluid flows (FIG. 5.6). As a result of centrifugal forces in the edge zone, as shown in Fig. 7, aerosol particles are deposited on the walls of open sipe channels in blades x 5, washed off with flushing liquid, are thrown onto the walls of housing 1, flow down them and the entire flow is removed from the separator through port 13. The purified gas stream is discharged through port 9.

Claims (3)

The economic efficiency of using the proposed centrifugal separator, compared with the known, is determined by the possibility of implementing new separation processes in the field of centrifugal forces that are unattainable in other devices, as well as an approximate comparison of comparable calculated technical and economic indicators of centrifugal separators. Claim 1. A centrifugal separator comprising a vertical cylindrical body, a hollow rotor with a bottom opening and blades, a lid, a drive, technological fittings, characterized in that, in order to increase productivity by increasing the separation factor of systems with different physical properties, the blades are made in the form of plates with slotted channels connected to the rotor cavity and open from the peripheral part of the front radial edges, and mounted on the rotor perpendicular to it 0 five 0 five the axle, on the bottom of the housing, under the blades, is a fitting for supplying the flow to be separated, and under the rotor hole, a fitting for extracting a stream with higher density, which is connected to a tube installed near the inner surface of the rotor, on the cover above the blades there is a fitting for sampling lower density and on the housing at the bottom there is a fitting to remove sediment. 2. Separator pop. 1, characterized in that the tube is tangentially bent in the opposite direction to the direction of rotation of the inner, surface of the rotor. 3. A separator according to claim 1, characterized in that, in order to ensure separation of aerosols, the slit-like channels of the plates are also open on the side of the peripheral edges, and a fitting for supplying the washing liquid, which is connected to the tube tangentially bent in direction, is located under the rotor opening rotation of the inner surface of the rotor. FIG. 2 FIG 3 fi.6