RU2479354C2 - Method of hydrodynamic cleaning of sediments from centrifugal fluid cleaner and device to this end - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to separation of emulsions in the filed of centrifugal forces and may be used for cleaning oil products and process fluids from impurities. Proposed method comprises transfer of impurities into suspended state. Note here that cap is axially shifted and locked relative to rotor as dirt accumulates on its wall. Thereafter, fluid is swirled by rotor to wash off dirt to be transferred into suspension to be removed from cleaner. Centrifugal cleaner comprises encased hollow shaft with feed and discharge branch unions and pressure disc fitted at sediment collector and communicated therewith. Besides, it comprises rotor including plate holder with top and bottom impellers and stack of conical plates arranged there between, and cap with plug mounted on said rotor. Said cleaner is furnished with seal and cap axial displacement and locking drive.

EFFECT: higher efficiency, faster cleaning, simplified design.

5 cl, 2 dwg

Description

The invention relates to the field of separation of suspensions in the field of action of centrifugal forces and can be used to clean oil products and process fluids from mechanical impurities.

Known separator for and.with. USSR No. 1011268 B04B 1/00, 04/15/83. Bull. No. 14 is an analog of the method and device of the claimed invention. The cylindrical conical drum of the separator contains a plate holder with a package of plates, which is mounted for rotation relative to the drum and is equipped with blades mounted on the outer surface of the package and located in the mud space of the drum. The separator can operate in three modes: with the same direction of rotation of the drum and the tray holder, their rotation frequency can be the same (first mode), different (second mode), or the directions of rotation of the drum and the tray holder are opposite (third mode). To ensure operation in these modes, the separator drum and the plate holder shaft are connected to the stators of two different electric motors.

The method of unloading the precipitate formed during the operation of the separator in the first mode consists in the destruction of the sediment by the blades when the separator is switched to other operating modes and removing it from the drum through the conical part, and when working in the second mode, the precipitate is carried away by the heavy liquid fraction in the process of separation of the initial liquid fractions, and when working in the third mode with washing liquid during washing the drum.

The disadvantage of this method is the limitation of its use only for slightly densified sediments, since the blades immersed in a highly densified sediment will not allow changing the rotation speed or direction of rotation of the plate holder to destroy the sediment, or a significant increase in the power of the separator motors compared to that required when the separator is operating in the first mode .

In addition, this method can be applied only to particles of contaminants (forming sediment), the density of which is slightly different from the density of the heavy liquid fraction with which they are carried away in the second mode of operation of the separator, since with a significant difference in densities the removal of particles from the drum against the action of centrifugal force in the conical part, it will require a significant increase in the flow rate of the liquid through the separator, which, in turn, will sharply worsen the quality of liquid separation into fractions, i.e. performing the main function of the separator.

The disadvantages of the separator itself include the complexity of its design, containing two electric drives, the operation of which must be coordinated for different modes of its operation.

Known centrifugal liquid cleaner with periodic discharge of sediment according to the patent of the Russian Federation No. 2093272 B04B, 1/04, 11/02, 20.10.97. Bull. No. 29 is a prototype of the method and device of the claimed invention. The cleaner includes a rotor mounted on a vertical axis and equipped with a drive, a cap covering a thin-layer insert placed above a cone-shaped shell with ribs, placed under the rotor and connected to it sediment collector and means for creating rotor vibration during the discharge of sediment using compressed air.

The method of unloading the sediment of the purifier in question consists in creating a means for oscillating the rotor up and down when compressed air is supplied to the purifier after it stops. In this case, inertial and hydraulic forces act on the sediment of contaminants in the cap and thin-layer insert, contributing to its sliding into the sediment collector.

The disadvantage of this method is that the hydraulic forces arising from the selection can erode only the surface of the sediment formed in the insert and on the cap, i.e. effective only with a small thickness of sediment. With a significant thickness of the sediment, inertial and hydraulic forces tear off the contaminants from the deposition surfaces in the form of large conglomerates, which, when sliding along the cone-shaped shell, get stuck in the narrowing channels between the ribs and clog the hole through which the rotor communicates with the sediment collector.

The disadvantage of the purifier itself is the difficulty of fine-tuning the means for creating vibration in a self-oscillating mode, which causes additional difficulties during operation, as well as the need to use for the discharge of sediment, in addition to electricity, another energy source (compressed air).

EFFECT: increased efficiency while reducing the time for unloading sediment of contaminants using a minimum volume of liquid, simplifying the design of a centrifugal cleaner while maintaining the quality of cleaning.

The technical result is achieved by the fact that in the method of hydrodynamic cleaning of a centrifugal cleaner from a sediment of contaminants, comprising a rotor connected to the drive with a cap mounted on it, including the transfer of contaminants into suspension, according to the invention, when contaminants accumulate on the cap wall, it is axially displaced and locked relative to the rotor then rotational motion is imparted to the liquid by means of a rotor, and contaminants are washed off and put into suspension, after which the suspension is removed of the cleaner.

The technical result is achieved by that. that a centrifugal liquid cleaner for hydrodynamic cleaning of sediment, including a hollow axis enclosed in a protective casing with inlet and outlet fittings and a pressure disk, located on the sediment collector and in communication with it, a rotor equipped with a drive, mounted on an axis and containing a plate holder with a bottom and the upper impellers, and the package of conical plates between them, mounted on the rotor of the cap with the stopper, according to the invention contains a mechanism for axial movement and locking of the cap relative to otorrhea, placed on top of the protective casing, wherein the cleaner is provided with a sealing device comprising a sleeve secured to the bottom impeller, and a sealing member mounted in the cap.

The technical result is also achieved by the fact that in the mechanism of axial movement and locking of the cap relative to the rotor and cap of the cap are formed mating protrusions, in the upper impeller, and also in the upper part of the cap are formed annular grooves, which serve to form radial gaps between the cap and the upper and lower impellers fixing the cap in the lower position relative to the rotor, while the axial clearance between the cap and the upper impeller is made larger than the axial clearance between the cap and the pressure disk.

The technical result is also achieved in the case when the mechanism of axial movement and locking of the cap relative to the rotor is made in the form of a screw pair.

The invention is illustrated by drawings.

Figure 1 shows a longitudinal section of a cleaner in the "liquid purification" mode, and figure 2 is a longitudinal section of a cleaner in the "sediment unloading" mode of pollution.

The centrifugal liquid cleaner includes a hollow axis1, mounted in a flange 2, having a nozzle 3 inlet and outlet 4 and mounted on a sediment collector 5 with a drain nozzle 6 through the membrane 7. A pressure disk 8 is fixedly fixed in the upper part of the axis 1. valves, respectively, 9 and 10.

A rotor is installed on the hollow axis 1 on the bearings 11 and 12, comprising a disk holder 13, a lower 14 and an upper 15 impellers and a packet of conical plates 16 between them. The tightness of the cleaner provides mechanical seal 17. The rotation of the rotor is carried out from the drive through the pulley 18, made on the lower impeller 14.

A cap 19 is mounted on the rotor with a stopper 20 on which a cylindrical protrusion 21 is made. The cap 19 is centered relative to the rotor on the seating surfaces 22 and 23. From the axial displacement upward under the influence of the fluid pressure when the cleaner is in the “fluid purification” mode, the cap 19 is fixed with a spring ring 24.

The tightness of the cleaner between the cap 19 and the lower impeller 14 of the rotor in the "fluid purification" mode provides a rubber ring 25, and in the "sediment unloading" mode, a sealing device containing a sleeve 26 mounted on the impeller and a sealing element 27 mounted in the cap.

Cylindrical grooves 28 and 29 are formed in the upper part of the cap 19 and the upper impeller 15, and the axial clearance 30 between the cap 19 and the upper impeller 15 is larger than the axial clearance 31 between the cap and the pressure disk 8 (Fig. 1).

For the safe operation of the cleaner, a protective casing 32 is mounted on the sump 5, in the upper part of which there is an axial movement and locking mechanism 33 of the cap 19, for example, in the form of a screw pair. A protrusion 34 is made on the movable screw of the mechanism 33, mating with the protrusion 21 of the tube 20.

A cavity 35 is formed for the passage of the liquid to be cleaned to the trays 16 and the collection of a precipitate of the selected contaminants between the cap 19 and the stack of trays.

In the mode of "unloading sediment" with the axial displacement of the cap in the cleaner (figure 2) between the cap 19 and the upper 15 and lower 14 impellers, radial clearances 36 and 37, respectively, are formed, which make it possible to exclude mechanical contact between the rotor and the cap.

The cleaner works as follows.

For the operation of the cleaner in the "liquid purification" mode (Fig. 1), the cap 19 is fixed in the upper position relative to the rotor with a spring ring 24 and centered on the seating surfaces 22 and 23. Through the open valve 9 and the nozzle 3, the purifier is filled with the liquid to be cleaned. Tightness is provided by the mechanical seal 17 and the rubber ring 25.

When the electric motor is turned on, the torque is transmitted to the rotor and through the cap through the V-belt drive and pulley 18. In this case, the liquid to be cleaned through the valve 9 and the nozzle 3 enters the rotor, where the impeller ribs 14 rotate to the angular velocity of the rotor and, using the pressure disk 8, flows through the cylindrical cavity 35, the package of conical plates 16, the upper impeller 15, the hollow axis 1, the nozzle 4 , open valve 10 and under pressure is supplied to the consumer. Bearings 11 and 12 are lubricated with cleaned fluid.

In the inter-tray gaps of the package of conical plates 16, under the action of a centrifugal field, the liquid is cleaned of mechanical impurities that settle on the inner surface of the hood 19. When a critical layer of sediment accumulates on the hood 19, the cleaner drive is turned off and the taps 9 and 10 are closed.

To implement the method, the purifier is transferred to the "sediment discharge" mode. The screw of the mechanism 33, located on the protective casing 32, the cap 19 is axially displaced axially 1 down, pressed against the pressure disk 8 and lock from rotation (figure 2). In this case, between the cap 19, the upper 15 and the lower 14 of the impellers, radial gaps 36 and 37 are formed, which exclude mechanical contact between them. Since the axial clearance between the cap and the upper impeller is larger than the axial clearance between the cap and the pressure disk, the cap does not come into contact with the upper impeller.

The tightness between the cap 19 and the lower impeller 14 provides a sealing device containing, for example, a sleeve 26 and a sealing element 27.

The next time the cleaner drive is turned on, the torque through the pulley 18 drives the rotor and the fluid in it. In addition to the circular rotation of the liquid in the cavity 35 between the packet of conical plates 16 and the sediment layer, intense Taylor vortices arise. The fluid velocity reaches several tens of meters per second, which leads to a significant hydrodynamic friction force on the surface of the sediment, its washing off and transfer to a suspended state. Moreover, suspended particles of pollution from the upper layers of the sediment, rotating with the liquid, enhance the flushing process from subsequent, more compacted sediment layers. It is enough 20-30 seconds of rotation of the rotor to transfer the entire sediment to a suspended state in the liquid.

After turning off the purifier drive, all sediment suspended in the liquid is drained from the purifier through valve 6 of sediment collector 5.

Subsequently, the cleaner is switched to the “liquid cleaning” mode by reverse rotation of the screw of the mechanism 33. In this case, the protrusion 34 of the screw of the mechanism 33, acting on the protrusion 21 of the plug 20, returns the cap 19 to the upper position and fixes on the seating surfaces 22 and 23. Subsequent opening of the valve 9, filling the purifier with liquid and turning on the drive ensure that the cleaning cycle is repeated.

Comparative analysis shows that, in comparison with the analogue and prototype, the proposed method of hydrodynamic discharge can be applied to highly compacted and having a significant thickness of precipitation, without compromising the quality of liquid purification during unloading. Moreover, the claimed cleaner is simple in design and easy to use.

Claims (4)

1. The method of hydrodynamic cleaning of sediment from contaminants of a centrifugal liquid cleaner containing a rotor connected to the drive with a cap mounted on it, including the transfer of contaminants into a suspended state, characterized in that when the contaminants accumulate on the cap wall, it is axially displaced and locked relative to the rotor, then attached rotational movement of the liquid using the rotor and carry out the flushing of contaminants and translating them into a suspended state, after which the suspension is removed from the cleaner. 2. A centrifugal liquid cleaner with hydrodynamic cleaning of sediment, including a hollow axis enclosed in a protective casing with inlet and outlet fittings and a pressure disk, located on the sediment collector and in communication with it, a rotor with a drive mounted on the axis and containing a plate holder with a bottom and the upper impellers and a package of conical plates between them, and a cap mounted on the rotor with a stopper, characterized in that it is equipped with a sealing device containing a sleeve mounted on the lower impeller And a sealing member mounted into the cap, axial movement mechanism and locking cap relative to the rotor, placed at the top of the protective casing. 3. The centrifugal liquid cleaner according to claim 2, characterized in that in the mechanism of axial movement and locking of the cap relative to the rotor and cap of the cap are made mating protrusions, and in the upper impeller and in the upper part of the cap are made ring grooves, which serve to form gaps between the cap, the upper and lower impellers when fixing the cap in the lower position relative to the rotor, while the axial clearance between the cap and the upper impeller is made larger than the axial clearance between the cap and the pressure disk. 4. The centrifugal liquid cleaner according to claim 2 or 3, characterized in that the mechanism of axial movement and locking of the cap relative to the rotor is made in the form of a screw pair.

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