RU2457039C1 - Cyclone - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to radial-flow devices and may be used in gas cleaners. Cyclone comprises inner and outer cyclone chambers arranged concentrically and provided with cover, inlet tangential branch pipe, and exhaust pipe. Confuser is connected to exhaust pipe and inner cyclone chamber bottom parts. Vanes are arranged on inner surface of outer cyclone chamber, regularly, along screw line for angular size of 360 degrees, to make a structure, downstream of dust-gas mix, to rule out dust particle loss in inner cyclone chamber. Every said vane represents section of cylindrical surface with its axis located on the wall of inner or outer cyclone chamber while guide surface represents that with radius equal to outer cyclone chamber radius. Vane height equals inlet tangential branch pipe cross-section height. Vane width and spacing between vanes are selected to make throat of said structure equal that of inlet branch pipe.

EFFECT: higher efficiency, lower flow friction and moisture content.

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Description

The invention relates to centrifugal type apparatuses and can be used for dust cleaning of gases in gas cleaning systems in the chemical, food, construction, pharmaceutical and other industries.

Known cyclone (RF patent No. 2006291, publ. 01/30/1994) containing a cylindrical or conical housing, a tangential inlet pipe, axial inlet and dust discharge pipes, a perforated chamber coaxially mounted inside the housing — a flow organizer.

The disadvantages of this cyclone are:

- the complexity of manufacturing a perforated chamber;

- difficulty in setting up and selecting perforation of the flow organizer for aggressive or toxic dust;

- one-stage cleaning leads to a partial radial entrainment of fine dust into the exhaust pipe.

Known two-stage cyclone (RF patent No.2013030, publ. 09/15/1994) (prototype), containing the outer and inner cyclone chambers installed concentrically and separated by a perforated partition. The cyclone chambers are provided with a cover in which the external and internal annular slit-like channels are made. Windows are made in the wall of the inner cyclone chamber, the vertical edges of which are provided with curved plates, the end of which is mounted on the outlet pipe. Between the wall of the inner cyclone chamber and the exhaust pipe, another perforated partition is mounted concentrically thereto at the outer diameter of the inner annular slit-like channel.

The disadvantages of this cyclone are:

- the complexity and intensity of the structure;

- movement of contaminated and purified streams in opposite directions near the outer wall of the inner cyclone chamber, divided by a partition;

- partial entrainment of polluted air through the exhaust pipe;

- high hydraulic resistance of the cyclone due to the presence of a large number of slots, partitions and oncoming flows;

- a high probability of arching from dust particles on the lid between the inner wall of the outer cyclone chamber and the outer annular channel.

The problem solved by the invention is to increase the efficiency of cleaning gases from dust, reducing the hydraulic resistance of the cyclone, eliminating the formation of dust arches in the dead spaces of the cyclone, reducing the degree of humidity of the cleaned air.

The problem is solved in that in a cyclone containing concentrically mounted inner and outer cyclone chambers provided with a cover, an inlet tangential branch pipe, an exhaust pipe, a confuser is attached to the lower parts of the exhaust pipe and an inner cyclone chamber, and from the connection point of the inlet branch pipe on the inner surface of the outer cyclone blades forming along the direction of movement of the chamber and the outer surface of the inner cyclone chamber along the helical line with an angular length of 360 degrees ylegazovoy mix design that avoids entrainment of dust particles settling into the inner cyclone chamber. Each blade is made in the form of a section of a cylindrical surface, the axis of which lies on the wall of the inner or outer cyclone chambers, respectively, and the guide is a circle with a radius equal to the radius of the outer cyclone chamber. The height of the blade is equal to the height of the cross section of the inlet tangential branch pipe. The angle of inclination of the helix, the width of the blade and the distance between the blades are selected so that the area of the passage section of the specified design is equal to the area of the passage section of the inlet pipe.

Figure 1 shows a General view of the cyclone; figure 2 is a section aa in figure 1; figure 3 is a section bB in figure 1; figure 4 - section bb in figure 1.

The cyclone contains a concentrically mounted cylindrical outer cyclone chamber 1 (see FIG. 1) with a wall 2 and a cylindrical inner cyclone chamber 3 with a wall 4, provided with a cover 5, an inlet tangential pipe 6 connected to the outer cyclone chamber 1, an axial exhaust pipe 7 and discharge pipe 8. To the lower parts of the exhaust pipe 7 and wall 4 of the inner cyclone chamber 3, a confuser 9 is coaxially connected, equipped with swirls 10 and 11. From the point of connection of the tangential pipe 6 to the cyclone on the inside f of the wall 2 and the outer side of the wall 4 along the helical line with an angular length of 360 degrees placed blades 12, forming a structure 13, eliminating the entrainment of the settling dust particles in the inner cyclone chamber 3 (see figure 4). The cross-sectional area of the structure 13 is equal to the cross-sectional area of the inlet pipe 6. Each blade 12 is made in the form of a section of a cylindrical surface, the axis of which lies on the wall of the inner 3 or outer 1 cyclone chambers, respectively, and the guide is a circle with a radius equal to the radius of the outer cyclone chamber 1 The height of the blades 12 is equal to the height of the cross section of the inlet tangential pipe 6.

The cyclone works as follows.

The dust-gas mixture through the inlet pipe 6 enters tangentially (tangentially) into the outer cyclone chamber 1. Dust particles passing through the structure 13 are discarded by the blades 12 to the inner surface of the wall 2.

The blades 12 of the structure 13, made in the form of a portion of a cylindrical surface, the guide of which is a circle with a radius equal to the radius of the outer cyclone chamber 1, allow for the tangential supply of dusty air into the outer cyclone chamber 1 to discard the largest part of the dust particles from the wall 4 to the wall 2 and exclude entrainment of settling dust particles in the inner cyclone chamber 3.

The angle of attachment of the blade 12 to the inner surface of the wall 2 or the outer surface of the wall 4, provided that the axis of the cylindrical surface, in the form of a portion of which each blade 12 is made, lies on the side surface of the outer 1 or inner 3 cyclone chambers, respectively, prevents swirling of the dust and gas mixture in the space behind the blade 12.

Since the cross-sectional area of the structure 13 is equal to the cross-sectional area of the inlet pipe 6, the structure 13 does not create additional resistance, and the conductivity of the cyclone does not decrease.

The passage of a dusty gas stream through the structure 13 is accompanied by vibration and a slight heating of the gas stream, which reduces the humidity of the incoming dust-gas mixture, eliminates the formation of condensate and prevents the formation of dust particles on the inner surface of the lid 5.

The swirling flow of the gas mixture with dust particles, passing through the structure 13, loses speed and falls down a spiral to the discharge pipe 8. When moving from the cylindrical to the conical part of the outer cyclone chamber 1, the gas flow changes direction and rises in the form of an inner swirling flow between the inner the surface of the wall 4 and the outer wall of the confuser 9. In this case, the internal flow captures smaller particles of dust from the external stream that do not have time to reach wall 2. The swirler 10 contributes to the unwinding of the internal stream cleaned from large particles of dust, directing the flow to the inner surface of the wall 4. Wall 4 separates the external and internal flows, preventing them from mixing with each other. In this case, dust particles carried away by the external flow to the wall 2 are not captured by the internal cleaned flow containing only small dust particles. The confuser 9, smoothly reducing the flow area of the inner cyclone chamber 3, increases (increases) the speed of the internal swirling flow. This stream, reaching the cover 5 through the inner cyclone chamber 3, changes direction and rushes in the form of a swirling stream into the space enclosed between the exhaust pipe 7 and the inner surface of the confuser 9. Small dust particles passing through the swirler 11 are twisted and discarded, separated from flow, to the inner wall of the confuser 9 (with zero flow rate) and poured to the discharge pipe 8. The cleaned air stream, once in the area of low pressure, changes direction and rushes to the exhaust pipe 7.

As a result of the fact that a three-stage gas purification from dust is implemented in this cyclone design, the application of the invention allows, on the same production area as in the prototype, to increase the efficiency of capture of small particles.

Reducing the number of partitions and slots provides, while simplifying the design, the elimination of oncoming flows and a decrease in the hydraulic resistance of the cyclone.

The use of the blades of the proposed configuration, their location prevents the formation of dust arches in the dead spaces of the cyclone, reduces the humidity of the removed air.

Claims (1)

A cyclone containing concentrically mounted inner and outer cyclone chambers provided with a cover, an inlet tangential branch pipe, an exhaust pipe, characterized in that a confuser is connected to the lower parts of the exhaust pipe and the inner cyclone chamber, and from the point of connection to the cyclone inlet branch pipe on the inner surface of the outer cyclone blades are arranged uniformly along a helical line with an angular length of 360 ° along the chamber and the outer surface of the inner cyclone chamber, forming along the direction of movement of the dust-gas mixture a design that eliminates the entrainment of settling dust particles into the inner cyclone chamber, each blade being made in the form of a portion of a cylindrical surface whose axis lies on the wall of the inner or outer cyclone chambers, respectively, and the guide is a circle with a radius equal to the radius of the outer cyclone chamber, and the height the blades is equal to the cross-sectional height of the inlet tangential nozzle, and the helix angle, the blade width and the distance between the blades are selected so that the area of the passage section Nia said structure is equal to the passage section area of the inlet pipe.

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