RU2183496C2 - Vortex dust separator - Google Patents

Abstract

FIELD: dry inertia-type cleaning in swirling gas flows. SUBSTANCE: vortex dust separator has cylindrical body which upper part houses conduit for uniform injection of secondary flow, vortex generator and branch pipe for discharge of flow of cleaned gas and which lower part includes stabilizing branch pipe for inlet of flow of dust-laden gas, vortex generator with washer and dust hopper. Innovation of given dust separator consists in employment of conduit for uniform injection of secondary gas into blade vortex generator which allows fields of velocities and pressure to be stabilized both across inlet into "rosette" and at start of separation. This stabilization makes it feasible to avoid carry-over of dust by spurious vortexes and consequently contributes to enhanced efficiency of cleaning. EFFECT: enhanced efficiency of cleaning. 2 dwg

Description

 The invention relates to dust cleaning devices operating on the principle of separation of dry dust in a spiral vortex gas flow. Application is possible in any processes requiring dust removal.

 Known devices consisting of a cylindrical body, two nozzles for the introduction of gas with flow swirls, a nozzle for the removal of purified gas, retaining washer and dust bin.

 When designing such devices, one of the main tasks is to solve the problem of unwanted dust entrainment, which significantly reduces the cleaning efficiency.

 The main reason for the entrainment of dust from separation vortex dust collectors (SVPs) is all kinds of vortex formations that can occur both at the boundary of uncomfortable surfaces and in the volume of interacting flows of primary and secondary gas.

 With regard to the first factor, developments are known (Patent of the Russian Federation 2096070, CL B 04 C 3/06, 1997) [1]; (USSR author's certificate 1627219, class B 01 D 45/12, 1991) [2], in which one way or another attempts were made to stabilize velocity fields in streams in order to eliminate or at least weaken the conditions conducive to the occurrence of parasitic vortices.

 In this application, the phenomena of dust entrainment are considered with reference only to the method of distribution of the secondary gas through the blade swirl.

 For the aforementioned and other SVP constructions, the rejection of nozzle distribution in favor of scapular swirlers is essential. This is explained by almost one reason: when a nozzle is distributed, a “torn” velocity field is formed along the secondary flow circuit in the separation chamber and this creates the prerequisites for the appearance of vortex cords that introduce an energy impulse to dust particles.

 Undoubtedly, from our point of view, the positive factor of the transition to distribution through the “outlet” has not fully exhausted the possibilities of eliminating the occurrence of parasitic currents.

 The closest technical solution is a vortex dust collector (Patent of the Russian Federation 2090268, CL B 04 S 3/06, 1997) [3]; consisting of a cylindrical body, in the lower part of which there is a primary flow inlet pipe with a speed stabilizer in front of the blade swirl and a retaining washer, and in the upper part there is a secondary flow pipe, a blade swirl and a pipe for the outlet of purified gas. A cylindrical cowl is mounted in the axial zone coaxially with the inlet pipe.

 The known design has a drawback that substantially affects the formation of parasitic vortices.

 The fact is that one of the main ideas when creating a VPU was laid down the condition for a smooth (unperturbed) merger of two vortex flows (hence the tangential approach), in which only centrifugal and inertial forces should manifest themselves. If these conditions are violated, then the prerequisites for the formation of vortex disturbances arise, introducing the energy momentum of the dust particles.

 Obviously, in the case under consideration, in order to create the mentioned favorable conditions when the flows merge in the separation chamber, it is necessary first of all to stabilize the static pressure and the velocity field in the pressure chamber in front of the blade swirl. And this can only be done by increasing the resistance of the "outlet" and reducing to 5% the ratio of the areas of its annular channel and the frontal area of the camera into which it is inscribed.

 However, the first condition will entail a possibly undesirable increase in the rate of gas outflow into the separation chamber, and the second - increased dimensions of the pressure chamber and, consequently, an increase in the cost of the entire VPU design.

 With the existing radial supply of secondary gas to the pressure chamber, it is very difficult or practically impossible to fulfill all the stabilization conditions in the pressure chamber.

 The aim of the invention is to increase the efficiency of the dust collector by eliminating conditions conducive to the occurrence of parasitic vortices in the separation chamber, as well as to reduce and, therefore, reduce the cost of the design of the VPU.

 This goal is achieved in that the pressure chamber with a radial gas supply is replaced by a uniform distribution channel, which is mounted along the entire upper contour of the blade swirl of the secondary gas stream.

 This ensures, firstly, the uniformity of the field of static pressures over the entire annular hole of the swirler, which allows you to align the velocity field at the entrance to the "outlet"; and secondly, to reduce the dimensions of the runway by eliminating the pressure chamber.

 The implementation of the proposed measures will reduce the entrainment of dust with purified gas and, therefore, increase the efficiency of dust collection.

 The drawing shows a diagram of a longitudinal section of a vortex dust collector.

 The vortex dust collector contains a cylindrical body, 1 in the upper part of which there are blades of a swirler 2, an outlet pipe for outputting purified gas 3, a stabilizing annular channel for uniform distribution of secondary gas 4 with a pipe for introducing a secondary stream. In the lower part of the housing 1 there is a coaxially located stabilizer 5, a primary flow swirl 6 with a retaining washer 7, a nozzle for introducing a primary dusty gas stream with a stabilizer 8 and a dust collector 9.

 The dusty gas stream enters the chamber 1 through the stabilizing channel 8 into the swirl 6, which forms an internal upward vortex flow in the chamber 1. From above, through the nozzle of the uniform distribution channel 4 and swirl 2, a secondary downward vortex flow of the same gas is formed. In the interaction of these cyclone flows in one direction, the suspended particles fall into the hopper 9 through the annular gap between the retaining washer 7 and the wall of the chamber 1, the purified gas enters the outlet pipe 3.

 Comparison with the prototype shows that the claimed separation dust collector has differences due to the installation of a uniform distribution channel along the upper contour of the scapular secondary gas swirler.

 Thus, the claimed separation dust collector meets the criterion of "novelty."

Sources of information
1. Patent of the Russian Federation 2096070, cl. B 04 C 3/06, 1997.

 2. Copyright certificate of the USSR 1627219, cl. B 01 D 45/12, 1991.

 3. Patent of the Russian Federation 2090268, cl. B 04 C 3/06, 1997.

Claims (1)

 Separation vortex dust collector, consisting of a cylindrical body, in the upper part of which there is a nozzle for introducing a secondary stream, a swirler and a coaxial outlet nozzle, and in the lower part there is a nozzle for introducing a primary dusty stream, a retaining washer and a dust hopper, characterized in that it is equipped a stabilizing ring channel of uniform distribution mounted throughout the entire upper contour of the scapular swirl of the secondary gas stream.