KR900002477B1 - Centrifugal force separator - Google Patents

Abstract

A centrifugal separator, for removing broken grains, husks, dust and other impurities from air, has a pre-separator chamber (2) with a tangential inlet (1) for the mixture of air and solid matter. A cylindrical shell (15) mounted coatially inside the pre-separator chamber has a grid (4) extending over part of its periphery and is connected to the coaxial clean air outlet. The pre-separator chamber is basically of cylindrical form and is mounted directly over a hopper (3). This hopper is separated by a curved wall (6) from the pre-separator chamber and there are openings (7,8) for the circulating air on each side of the chamber. The separator extracts dust from the air more effectively.

Description

centrifugal

1 is a schematic cross-sectional view of the present invention centrifuge.

2 is a cross-sectional view taken along the line II-II of FIG.

3 is a schematic cross-sectional view showing a combined structure of the suction passage and the centrifuge.

4 is a sectional view taken along line IV-IV of FIG.

5 is a cross-sectional view showing the guide state of air and dust.

* Explanation of symbols for main parts of the drawings

1 mixer inlet 2 preliminary separation chamber

3: collection room 4: branch grid

5: clean gas outlet 6: branch plate

7,8: air chaos opening 12: fan

16: guide 17: air passage

21: suction passage 28: double control wall

30: radial fan

The present invention relates to a centrifuge for separating grain crushed powder, shells, dust and other impurities from air, in particular to detect a pre-separation chamber, in which the gas to be separated, ie the inlet of the mixer, is installed in the binding direction The present invention relates to a centrifugal separator characterized in that a cylindrical fixed branch grating is installed coaxially and a clean gas outlet extends in an axial direction with respect to the branch grating.

Centrifuges have been used successfully for decades in the milling and feed grinding industries. The main advantage of a typical cyclone separator will be its simple structure and relatively low air resistance. Generally, the cyclone is installed vertically or slightly inclined from the vertical. The separated material is collected at the bottom and discharged through the reservoir.

The air leaves the cyclone after several vortex movements at the uppermost part through so-called through pipes installed in the coupling direction at the upper side of the cyclone and installed to be inserted into the inside of the cyclone.

The main drawback of cyclone separators is their relatively low separation efficiency.

Due to fluctuations in air pressure and changes in dust content in the air, a number of secondary vortices are induced in the cyclone, which makes it difficult to improve the separation efficiency when using the cyclone. Another drawback is that in the milling and feed grinding industries, the cyclone exhaust air contains dust or grains in excess of the legal limits.

In industrial systems, the cyclone discharge air must be additionally filtered and filtered through the filter before it is released to the atmosphere.

A number of proposals have been made to improve the cyclone separator, but few of these proposals have made progress in actual operation.

One of the selected proposals is described in DAS 1 078 859. In this case the centrifuge has a horizontal axis. Such centrifuges are dual centrifuges consisting of primary and secondary separators. The primary separator is a nearly circular spiral, the mixer inlet is installed in the joining direction, and similar to a typical cyclone separator, when a clean air and dusty external air layer is directed to a small secondary separator, each separated at both ends. Some deviation from both ends of the spiral separation chamber.

The advantage of this separator is that the pressure drop is very large, and the drawback in this case is that the separation effect such as dust is insufficient. The recent trend seems to consist of a unique purifier in the mill that requires a significant amount of air, for example as an air recirculator, as shown in GB-PS 1 536 905.

Air recyclers require relatively clean air for two reasons.

When recirculating the air, a considerable amount of dust is still contained in the air, so there is always a risk of bacterial contamination when it is for processing raw materials for human use.

If there is a significant amount of dust in the recirculated air, the dust will get caught and shorten the life of the whole machine. Since these obstacles occur frequently, cleaning must be performed.

The quality conditions of the recycled air should not be higher than those specified in the regulations for industrial discharged air to the atmosphere, but experience has shown that it is higher than the known centrifugal force or the efficiency of a cyclone separator.

It is an object of the present invention to provide a centrifuge which is better in terms of pressure drop and technical structure than in conventional cyclone separators and has a good separation effect of dust. The centrifugal separator is used to break grains, shells and dust and other impurities in grains. It is suitable as a separator for separating the oil, in particular in combination with other grain washing and processing equipment for an air recirculation device.

The centrifuge of the present invention is characterized in that it consists of a rotating zone "X" for the centrifugal force for circulation of the recirculated air and a protected internal air outlet "Y" which does not cause vortex through the branch grid. Therefore, the above-mentioned problem is that a completely controllable separation chamber having two flow technologies is formed, and the separation effect of impurities in the air is excellent, which is solved by the present invention.

The present invention also enables a considerable advantageous structural design.

The pre-separation chamber is advantageously circular and mounted directly on the hopper collector, which is separated from the pre-separation chamber by the curved dividing plate and formed with air circulation openings on both sides of the dividing plate. have.

The present invention was directly tested by connecting to a suction passage containing a preselected amount of dust, and the initial test apparatus showed surprisingly good results, particularly with respect to conventional problems. The bent portion of the primary separation chamber communicated in the coupling direction smoothes the flow direction of the gas flowing in the mixer inlet, which prevents confound vortices in the preliminary separation chamber. In this respect it is proved to be particularly important to allow the mixer flowing in the joining direction to flow over the entire length of the pre-separation chamber. In most cases, the effect of separating dust is greatly weakened if only one side is introduced in the joining direction. For example, in the special case of classifying dust, this drawback is more problematic.

The best solution so far has been that the mixer inlet is installed at the top of the pre-separation chamber so that the flow of air in the pre-separation chamber is directed clockwise as the air flow at the mixer inlet leaves the upper side of the pre-separation chamber from the bottom. . When the branch grid is installed with air passage in the upper side, the air flow is stable and the separation effect of air and impurities is excellent. The air is remarkably increased after almost half a turn at a position close to the wall of the preliminary separation chamber, whereby almost all foreign matter is transferred to the hopper-type collection chamber through the outer part of the airflow.

In this way, the collection room has two main tasks. The debris falls into gravity and all air flow to the collection chamber is reversed in the collection chamber and directed to the preliminary separation chamber through the other air circulation opening, so the centrifugal force acts again. At this time, a considerable amount of dust or shell particles cannot be prevented from piggybacking in the air stream. They will eventually reach the bottom of the collection chamber, though they pass through secondary or more than one passageway.

The internal flow of air flows into the curved branch plate in the space between the curved branch plate and the branch grid. Statistical laws do not prevent small amounts of dust particles and grains from being piggybacked in the air. Several other advantageous structural features have been found to be suitable for the purpose of cleaning the internal flow of this foreign material.

As such, the branch lattice has an open portion through which air can pass only on the lower side, and is preferably installed near the branch plate curved in a semicircular shape.

The branching grid has guide vanes installed in the transverse direction with respect to the flow of air, and a passage through which air passes through the guide vanes is formed at a branching angle of 90 ° or more with respect to the flow of air. The outflowing air is preferably configured to be introduced into the branch grid so that no vortex occurs. The air outlet from the collection chamber forms an air circulation opening, which is installed in the vicinity of the mixer inlet.

The space between the branch lattice and the circularly curved branch plate protrudes toward the air circulation opening partly in the form of a spiral cone. The branch grid is closed at an angle of more than 180 ° so that air flows in the transverse direction without vortex. In addition, a circularly curved branch plate is designed to start at the height of the axis and extend beyond an angle between 90 ° and 180 °. The suction fan is properly installed at the end side of the clean gas discharge port, and the dust discharge port is disposed at the lower side of the collection chamber.

As already mentioned, the new centrifuges have combined remarkable results in combination with suction passages for grain applications. In this case a significant amount of heavy grain would have to be separated by a suction passage from all foreign matter, ie shells, dust and grain breakdown. The problem thus far has been the complete and economic separation of relatively large quantities of foreign matter from the air. There have been satisfactory developments over the years as far as this is concerned.

The present invention shows a very special advantage.

The upper end of the vertical suction passage is configured to serve as a preliminary material as the mixer inlet. The clean gas outlet is connected to the lower inlet of the suction passage as a recirculation passage so that the suction passage can be used as a passage of the recirculated air. As the back wall of the suction passage is known, the angular position is adjusted and the horizontal direction is double-controlled to separate the grain crushed powder required from the suction passage and to separate the remaining grain crushed powder, shells and dust from the centrifuge. Best results were obtained.

Referring to the present invention in more detail based on the accompanying drawings as follows.

In FIGS. 1 and 2, the main components of the centrifuge consist of a mixer inlet 1, a preliminary separation chamber 2, and a hopper type collection chamber 3, which are installed in the coupling direction as shown in FIG. . In the preliminary separation chamber 2 in a circular shape, a branch grid 4 is fixedly installed, and a clean gas outlet 5 is protruded at an axial end thereof. A semicircular curved branch plate 6 is installed at the bottom of the preliminary separation chamber 2, and air circulation openings 7 and 8 are formed at both sides of the branch plate 6, respectively.

The branch plate 6 (right side in FIG. 1) extends from the axial height of the branch grid 4 and extends over a range of 90 ° or more to the left side of the drawing.

The branch plate 6 is made of a simple steel plate, and is bent at the same curvature in the separation chamber 2 and the collection chamber side in both directions. The lower side of the branch plate 6 may extend to the position shown by the dashed line 10 so that the flow of air to the collection chamber can be radically switched. In the collection chamber 3, a conical hopper 11 and a fan 12 for discharging dust are installed.

By connecting the mixer inlet 1 directly in front of the straight passage 13, it has proved advantageous to ensure the smoothest flow of air in the range of the mixer inlet 1.

The mixer inlet 1 is separated from the preliminary chamber 2 in an arc range close to 90 ° by the wall 14.

The upper part of the separation grid 4 is configured to allow air to pass therethrough, and is composed of a cylindrical jacket 15.

A plurality of guide pieces 16 are installed in the lower portion of the branch grid 4, and one air passing hole 17 is formed between the two guide pieces 16, respectively. The tip of the guide piece 16 is bent at an angle greater than 90 ° toward the air flow direction.

This structure is directed in the direction of flow of air. However, because of their inertia, the fine dust cannot be directed in the direction of air flow and changes direction to separate into the separation chamber 18 along the inner wall of the branch plate 6 at the position of the air circulation openings 7 and 8, and a small amount of dust. The air containing bays is returned back to the range of the tip end of the wall 14 of the mixer inlet 1. These dusts will separate into the collection chamber 39 during the second repeated pass.

The air passage hole 17 is directed radially inward, thereby controlling the flow of air directed only in one direction in the preliminary separation chamber 2 and discharging some clean air without vortex to the air outlet Y side. .

The air rotation zone "X" for the centrifugal force is shown by the oblique line in FIG. In this separation chamber, strong air circulation takes place, and the centrifugal force gives the dust particles an opportunity to repeatedly separate into the area "D".

The vortex-free air outlet "Y" is surrounded by a rotating zone "X", which is sufficiently separated and protected to separate clean air from the remaining dust.

3 and 4 show another embodiment, in which a new centrifuge is combined with a vertical suction passage. This embodiment first allows the selective separation of low-quality grains and fine grains containing unnecessary dust and foreign matter with the aid of air.

As a screening agent, coarse impurities larger than ordinary grains are separated and stones are separated by a stone separator. This separation process is preferably done in advance.

The new separation process consists of four successive operating steps.

Zone A is a preseparation zone as already known. In this area, unseparated grains are fed and effective intake by air injection is achieved. All heavy grains fall to the bottom and medium-sized ones are transferred to the area (B) of the siali suction passage in the air stream with light impurities. Zone (B) allows medium grains to be separated back into heavy, fine grains and light ones, and light grains or debris are transferred to the preliminary separation chamber (2) outside the silage zone (C).

In addition, the sorting in the suction passage is made as is known, whereby the flow form in the suction passage is changed to the form for the separation of the fine particles. Depending on the rate of drop of each particle, these particles will fall to the bottom at uneven height in the passage by the flow of air. This process will be repeated several times until the particles are towards the top or completely at the bottom.

Zone A and zone B communicate without any obstruction so that the flow of air is activated to obtain an effective force. This feeds the grain into the stream of air to separate the grains from debris and to convey the crushed powder to be separated by air. The functions of the regions C and D are fundamentally different.

The gist of the present invention is that all foreign matter concentrated in the outer edge region is separated in the preliminary separation chamber 2 as much as possible. Foreign matter in the outer edge layer is transferred to the area D through the air circulation opening 7 and back to the collection chamber 3 to remove almost all foreign matter. Grain dispersed by the interaction of both regions (C) (D) is preliminary separation chamber (2) -collection chamber (3), which is mixed in the flow of air and transferred from the collection chamber (3) to the preliminary separation chamber (2). Is finally collected in the collection chamber 3 by a second, third, or more repeated passage of. Very small dust in the preliminary separation chamber (2) is contained in the clean air passing through the branch lattice (4), which is solved through a device acting as an air recirculation system.

Such a device is shown in FIGS. 3 and 4. Unseparated grains are supplied to the suction passage 21 through the feeder 20. This grain is supplied to the small preliminary supply chamber 23 through the supply pipe 22.

The eccentric drive device 24 may be arranged in the form of a grain curtain of uniform length and thickness so that the grain is supplied to the suction passage 21 by vibrating the elastically supported feed table 25. Air is transferred from the recirculation passage 26 through the grain curtain to the suction passage 21. Since the double adjustment wall 28 is located in the suction passage 21, the width of the suction passage 21 can be adjusted in the flow direction thereof. The suction passage 21 may have a vertical cross-sectional area. It may also have a V shape of the cross-sectional area enlarged in the flow direction or a reduced cross-sectional area in the flow direction. In the form shown, the radial fan 30 is installed close to the region of the clean gas outlet 29 so that the required air circulation can be achieved.

The entire air is recycled through the recirculation air passage 26. Guided to the discharge hopper 32 side of the sorted grain, the flap 33 is installed in the hopper so that disturbance by air or unnecessary vortex does not occur. In addition, the separated impurities are transferred differently and guided to the rotating fan 12. The amount of air can be adjusted by adjusting the number of revolutions of the fan. The arrangements of FIGS. 3 and 4 can be operated in part as a recirculation system. The entire apparatus may be configured in a state in which a weak negative pressure is applied through the intake portion 34 having the air regulating flap 35.

It is also possible to configure the branch grid 4 rotatably. In such a case, the upper part of the branch grid 4 constituting the jacket 15 through which air does not pass may be configured to float.

The jacket 15 may be configured with an opening for inflow of air within a range in which grain is not rebounded. In addition, the jacket 15 should be closed outside the portion where the mixer inlet 1 is surrounded by the branch plate 6, which is the way through which the preliminary separation chamber 2 passes.

FIG. 5 shows a structure having two interesting configurations, for example, compared to the configuration according to FIG. 1.

The vertical passage portion 40 operates as a suction passage as in FIG. 1, but a refill chamber 41 is formed at the rear side adjacent thereto so that the preliminary separation chamber 2 and the recirculation passage 26 (FIG. 4) are respectively formed. When the air circulates, a portion of the air in the passage portion 40 and a portion of the air in the refill chamber 41 can circulate. The optimum amount of air can be set by the adjusting flap 42. Therefore, the air speed in the passage portion 40 and the preliminary separation chamber 2 as well as the amount of air can be properly adjusted. This adjustment is made by an adjustment flap 42 that regulates the flow of air as shown by two arrows 43 and 44.

In addition, the air flow in the preliminary separation chamber 2 can be adjusted to the other flaps 45, and a considerable amount of air can flow to the area "X" or to the internal air outlet side Y without vortex. In this way, the amount of clean air flowing through the air outlet (5) may be affected but does not affect the air velocity in the separation chamber (18) and the air circulation opening (7), and at the same time air containing dust It is only guided inward or outward. The two zones "X" and "Y" are not affected and can be separated even in very difficult separation problems, eg in the case of cornmeal.

Claims (15)

It has a preliminary separation chamber (2), the mixer inlet (1) is disposed in the coupling direction, and the fixed fixed grating grating (4) of the coaxial coaxial form inside the installation, the clean gas outlet ( In the centrifugal separator which removes various impurities from grains 5) extending in the axial direction, the preliminary separation chamber 2 is formed in a circular shape, and the preliminary separation chamber 2 and the hopper-type collection chamber below it are formed. The curved branch plate 6 is disposed between (3), the air inlet opening (7) (8) is formed on both sides of the preliminary separation chamber (2) and the mixer inlet (1) disposed in the coupling direction is It consists of a curved part in the flow direction to the preliminary separation chamber 2 side, and an air impermeable part is comprised in the upper part of the said branch grid 4, The branch grid 4 has an air passage hole only in the lower part. (17) to have internal rotational zone " X " and non-rotational discharge zone " Y " Centrifuge characterized in that. The centrifugal separator according to claim 1, characterized in that the air passage hole (17) is formed above the circularly curved branch plate (6). A centrifuge according to claim 1, characterized in that the branch grid (4) consists of guide pieces (16) arranged transverse to the direction of rotational flow. A centrifuge according to claim 3, characterized in that the air passage hole (17) is formed at a branching angle of 90 ° or more with respect to the air flow between the guide pieces (16). 5. Centrifuge according to claim 4, characterized in that the air passage hole (17) is installed so as not to cause vortex in the air flowing into the clean gas outlet (5). A centrifuge according to claim 1, characterized in that the air circulation opening (8) is formed in the preliminary chamber (2) in the region of the mixer inlet (1). A centrifuge according to claim 1, characterized in that the space between the branch lattice (4) and the circularly curved branch plate (6) is in the form of a spiral cylinder. 8. Centrifuge according to claim 7, characterized in that the space between the branch grid (4) and the circularly curved branch plate (6) extends in part towards the open side of the air circulation (8). A centrifuge according to claim 1, characterized in that the angular range of at least 180 ° of the upper section of the branch grid (4) is closed. The centrifugal separator according to claim 1, characterized in that the circularly curved branch plate 6 encloses an angular range between 90 ° -180 ° starting in the flow direction at the axial height of the branch grid 4. . 6. Centrifuge according to claim 5, characterized in that the fan (30) is mounted on the end side of the clean gas outlet. A centrifuge according to claim 1, characterized in that the collection chamber (3) is closed at its lower side with an air exhaust fan (12). Centrifuge according to claim 1, characterized in that the mixer inlet (1) corresponds to the upper end of the vertical suction passage (21). 14. Centrifuge according to claim 13, characterized in that the clean gas outlet (5) is connected to the lower inlet of the suction passage (21) so that air is recirculated in the suction passage (21). 14. Centrifuge according to claim 13, characterized in that the dual adjustment wall (28) of the suction passage (21) allows the angle and the horizontal position to be adjusted.

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