SU1337121A1 - Dust separator - Google Patents

Abstract

The invention relates to a technique for purifying gases from dispersed impurities and improves the efficiency of gas dedusting at high concentrations of particles in the stream by controlling the flow rate of gas through the receiver and the twist of flow in the separation elements. The transported dispersed material in the nozzle 2 of the inlet under the action of centrifugal forces is concentrated at the periphery and with part of the gas enters the receiver 3, where it is released from the stream. Gas with unseparated particles from the nozzle 2 and the receiver 3 enters the vortex chamber 1, where it is twisted and led out through the outlet nozzle in the radial-axial direction and along the periphery through the window 4 into the nozzle 2. The magnitude of the flow is regulated by the position of the gates 9, 10, 11 An increase in the efficiency of gas dedusting is achieved by the fact that a window 4 is made in the chamber wall, which communicates with the inlet 2, and the slots 5, 6 and window 4 are equipped with adjustable gates 9, 10, 11, and the corners between the radii passing through the centers window and the slots are 100-140 °, the vortex chamber 1 is provided with an outlet nozzle located on its end wall and a shell with a diameter larger than the output nozzle and 0.15-0.25 width of the chamber coaxial with it, and the axial nozzle The purge gas outlet is recessed into the vortex chamber at a distance of 0.3-0.4 chamber width. 2 Il. (L WITH o

Description

The invention relates to a technique for cleaning gases from disner impurities, mainly in the installations of pneumatic transport of powdered materials.

The purpose of the invention is to increase the efficiency of dedusting of gas at high transport concentrations of particles in the stream by controlling the flow rate of gas through the receiver and the twist of flow in the separation elements.

FIG. 1 shows a dust separator, general view; in fig. 2 shows section A-A in FIG. one.

The dust separator contains a curvilinear vortex chamber 1 with a nozzle 2 of the input and a receiver 3, communicating between each other by means of a window 4 and w, spruce 5, 6, located relative to each other by an angle of 100-140 °. An axial nozzle 7 of the cleaned gas outlet and a shell 8 are fixed in the chamber. The window 4 and the slots 5 and 6 are equipped with gates 9, 10 and 11 for adjusting their flow sections. The pipe 2 is connected to the receiver 3.

The device works as follows.

The transported dispersed material in the nozzle 2 of the inlet under the action of centrifugal forces concentrates at the periphery and enters part of the gas in the receiver 3, where it is released from the stream due to overload and inertial forces. Gas with non-separated particles from nozzle 2 and receiver 3 enters the vortex chamber.

1, where it is twisted and drawn out in the radial-axial direction through the nozzle 7 and along the periphery through the window 4 into the nozzle

2. At the same time, in the core of the swirling flow located between the end boundary layers, the radial velocities of the gas are much less than in the boundary layers, and the centrifugal forces in the zone near the outlet nozzle and on the boundary of the induced vortex are maximum, therefore particles arriving in the region of intense twist of flow from the boundary layers in the axial direction, goes into the core and is directed to the periphery of the chamber, from where it enters the nozzle 2. In the contour of the nozzle 2 - receiver 3 - vortex chamber 1 - nozzle 2 a circulation flow is formed due to ejection effect of the gate 9, and the magnitude of this stream is governed by the position of the gates 9, 10 and 11. This stream, depending on the dispersion and concentration of dust, as well as autohesion characteristics, is chosen so that it is sufficient for W.d. from the vortex chamber, separation in the particle transport channel to the receiver, and was small to prevent dust from being washed out of the receiver. Particles coming from the nozzle channel to

the vortex chamber passes twice as large as the gas into the border. on the butt and on the surface

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neck distance to window 4 than particles emanating from the receiver and located closer to the chamber surface, which ensures the equal possibility of unloading the flows coming from the pipe pipe and the receiver with an increased concentration of fine dust in these flows.

The specified angle 100-140 ° of the position of the window 4 with respect to the slits 5 and 6 is explained by the need to ensure 10 sufficient time for the separation of particles relative to the gas flow lines, in the pipe 2, the receiver 3, the swirl chamber 1 (the greater the angle, the longer separation).

In order for the particles to be separated in the pipe 2, the time of passage of particles when centrifugal forces are applied to them from window 4 to the slot communicating with receiver 3 must be less than or equal to the time of gas passing from window 4 to slot 5. Otherwise particles will enter chamber 1.

Similarly, for a particle trapped in the receiver 3, it needs the time it leaves the curved gas flow due to inertial forces when the flow is rotated.

Particles located at the end of gate 11 must also have a time to travel to window 4, and particles located at the end of gate 10 must have even longer time to reach window 4.

In a real process, which is of a probabilistic nature, a strong flow turbulization occurs in the vortex chamber in the slit inlets, since a strong gas velocity gradient is observed near the gaps. If the slots are placed closer to window 4, i.e. the angle between window 4 and slit 35 6 to make less than 100 ° will dramatically decrease the efficiency, since the particles, instead of entering window 4, are washed out by turbulent pulsations.

If you increase the angle between window 4 and 40 with slot 5 over 140 °, the efficiency will also be lower. This is due to the fact that the particles exit from the slit zone to the periphery into a highly turbulent flow and do not flow into the window 4.

The role of the shell is that 45 it encloses the zone of the formation of a forced vortex. It is known that in the vortex chamber in the paraxial region a forced vortex is formed, in which the gas rotates as a solid. This vortex originates on the face surface. Where this vortex originates, there is an intense leakage of gas to it in the boundary layer (like a tornado), which leads to an increased entrainment of particles (there are more radial gas velocities than circumferential flow). If this zone of flow is enclosed, then leakage will occur through the zone of intense gas rotation, i.e.

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These shells, interacting with the core of the flow, will unwind, and then from the inside of the shell, with a small number of particles, will join the forced vortex.

In the vortex chamber on a curvilinear surface due to the Taylor – Hetler vortices, the gas is pressed to the end surfaces and in the boundary layer near the end surfaces moves toward the axis. In the core of the flow between these layers, the radial gas flows to the axis are imperceptible compared with the radial flows in the boundary layers. Near the surfaces of the shell and the nozzle for discharge of the purified gas, the gas moves towards the axial direction and unwinds, interacting with the flow core. The particles are transferred to the core and are moved to the periphery. At certain ratios of the diameters and diameter of the pipe, the output of the cleaned gas and the shell is the most intensive process. These relationships are found from experiment.

So, for example, with increasing depth of the clean gas nozzle, the dust content of the clean gas decreases with fixed values of shell dimensions and with increasing shell diameter and depth, with noticeable tendency to establish a constant dust content with a depth of more than 1/3 of the chamber width. In the range of changes in the depth of the shell (width) from 0.15 to 0.25 the width of the chamber, and also increased /

The dust content of the cleaned gases is not significantly reduced by its diameter.

When the axial nozzle 7 of the clean gas outlet is deeper by 0.3-0.4 chamber width, shell by 0.15-0.25 chamber width and flow regulation by the position of the gates, the dust content at the outlet of the dust-separator is reduced by 5-10 times.

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Claims (1)

Invention Formula A dust separator containing a curvilinear vortex chamber, a receiver in its lower part, an inlet nozzle communicating with each other by means of slots, an axial nozzle of the cleaned gas outlet, characterized in that in order to increase the efficiency of dedusting at high transport concentrations of particles in the stream by adjusting the gas flow through 0 receiver and adjusting the twist of flow, a window is made in the wall of the chamber, communicating with the inlet nozzle, while the slots and the window are equipped with adjustable gates, and the angles between the radii passing through the centers of the window and the slots are 100-140 ° The vortex chamber is provided with an opposite outlet pipe located on its end wall and a shell with a diameter larger than the outlet nozzle and 0.15-0.25 wide, the chamber width coaxial with it, and the axial outlet pipe of the cleaned gas is buried in the vortex chamber for distance 0 3-0.4 camera width. /four b .5} H ) Fig2 Compiled by S. Gorinova Editor M. TovtiaTehred I. VeresKorrektor I. .Musk Order 4073/9 Circulation 656 Subscription VNIIPI USSR State Committee for Inventions and Discoveries 113035, Moscow, Zh-35, Raushsk emb., 4.5 Production and printing inception, Uzhgorod, ul. Design. four