JP3006962B2 - Cleaning device for rotating drum screen - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus using a rotating drum screen for sludge treatment and solid-liquid separation in a process.

[0002]

2. Description of the Related Art Separation methods using a rotary drum screen for sludge treatment and solid-liquid separation in the process further increase the throughput compared with conventional solid-liquid separation methods using a stationary screen or a vibrating screen. It is an excellent solid-liquid separation method that eliminates vibration noise pollution.

[0003] This method is a solid-liquid separation method in which raw materials to be treated are continuously charged into a drum screen, a filtrate falls from the drum screen, and solids remain in the drum screen. However, this solid-liquid separation method works effectively in the first round of the drum screen, but as the second round and the third round of the drum screen go round, the solids left inside the drum screen are stacked and finally Will completely cover the eyes of the screen and the screen will not perform its filtering function. Therefore, in this case, the operation of the drum screen is stopped, the clogging is cleaned, and then the operation is performed again, so that the advantage of the continuous operation is lost.

Therefore, as a modification of the drum screen, a spray nozzle is provided on the outside or inside of the rotary drum screen in a type fixed at one place of a filtering device, and washing water is sprayed to the screen surface. Is performed.

[0005]

This cleaning device has some cleaning effect on a slowly rotating drum screen. However, when the drum screen rotates at a high speed of, for example, several hundred revolutions per minute or more, such a cleaning device becomes effective. With a spray nozzle system fixed at a fixed position of a filtration device, the sprayed washing water is repelled by a screen drum frame or a screen wire rotating at a high speed, and it is almost impossible to completely clean the eyes of the screen. In this method, no cleaning is performed until the rotating drum screen returns to the home position of the spray nozzle again. Even if the washing is performed at the fixed position, the effect cannot be expected very much in a moment. In addition, the liquid is viscous,
If solids are caught in the eyes of the screen, washing can hardly be achieved with a single shot.

[0006] Originally, a rotary type drum screen is intended to rotate a drum at a high speed and apply a centrifugal force to separate an object to be processed which is difficult to separate by the centrifugal force. Further, since the centrifugal force is applied, the solid adheres to the filtration surface of the drum screen. If the solid is peeled off and the filtration surface is not washed, the filtration function cannot be provided for the sequentially supplied workpieces. However, there is a technically unsolved problem that this conventional problem cannot be sufficiently solved by the above-mentioned conventional fixed-position type cleaning water injection nozzle system.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems that occur when a rotary drum screen is rotated at a high speed to perform solid-liquid separation. It is an object of the present invention to provide a rotary drum screen cleaning apparatus capable of effectively removing solids and completely maintaining the filtration function of the screen by thoroughly cleaning the screen eyes.

[0008]

According to the present invention, there is provided a rotary drum screen cleaning apparatus which achieves the object of the present invention. A rotary cleaning mechanism arranged so as to be rotatable in a circumferential direction of the rotary drum screen, and a rotary drive mechanism capable of rotating the rotary cleaning mechanism independently of the rotary drive of the rotary drum screen. .

According to one embodiment of the present invention, in the above apparatus, the rotary cleaning mechanism is driven to rotate in the same direction at the same rotation speed as the rotation speed of the rotary drum screen.

According to another embodiment of the present invention, in the above apparatus, the rotary cleaning mechanism is driven to rotate in the same direction at a rotation speed different from the rotation speed of the rotary drum screen.

According to another embodiment of the present invention, in the above apparatus, the rotary cleaning mechanism is driven to rotate in a direction opposite to the rotary drum screen.

In the above apparatus, the rotary cleaning mechanism may be configured to be rotatable about its central axis.

[0013] In the above apparatus, the rotary cleaning mechanism may include at least one pressure fluid injection pipe extending in the axial direction of the rotary drum screen and having a plurality of pressure fluid injection ports or injection nozzles formed at predetermined intervals. And a pressure fluid supply mechanism for supplying a pressure fluid to the pressure fluid ejection pipe.

The rotary washing mechanism may be constituted by a brush extending in the axial direction of the rotary drum screen.

The rotary washing mechanism may be constituted by a solid scraping plate extending in the axial direction of the rotary drum screen.

[0016] The rotary washing mechanism is formed by a tapping plate extending in the axial direction of the rotary drum screen and a frame provided on the rotary drum screen, and is engaged with the knocking plate as the knocking plate rotates. It may be composed of a plurality of projections that apply vibration to the beaten plate.

Further, the rotary drum screen is formed in a polygonal cylindrical shape, and the rotary cleaning mechanism includes a knocking plate extending in an axial direction of the rotary drum screen, and a knocking plate associated with rotation of the knocking plate. It may be constituted by a corner of the rotating drum screen that engages and applies vibration to the knocked plate.

The rotary cleaning mechanism may be constituted by a vibration generator mounted on a rotary drum screen or another rotary cleaning mechanism.

Further, the above-described cleaning apparatus for a rotary drum screen which achieves the object of the present invention is integrated with the rotary drum screen at least at either the outside or the inside of the screen surface as viewed from the rotation axis of the rotary drum screen. A rotating washing mechanism attached to the rotating drum screen so as to rotate.

In this cleaning apparatus, the rotary cleaning mechanism extends in the axial direction of the rotary drum screen and has a plurality of pressure fluid injection ports or injection nozzles formed at predetermined intervals.
A plurality of pressure fluid ejection tubes arranged at predetermined intervals in the circumferential direction of the screen, and a pressure fluid supply mechanism for supplying a pressure fluid to the pressure fluid ejection tubes may be provided.

Further, the rotary cleaning mechanism may be constituted so as to be rotatable about its central axis.

[0022]

According to the present invention, the rotary washing mechanism disposed at least on either the outside or the inside of the screen surface is rotated by the rotary drive mechanism in the circumferential direction along the screen surface independently of the rotation of the rotary drum screen. It is driven to rotate.
Therefore, the rotation speed of the rotary cleaning mechanism is set to an optimum rotation speed for cleaning the screen surface in accordance with various conditions such as the operating conditions of the rotary drum screen and the conditions of the object to be solid-liquid separated. By rotating the rotation drive mechanism, the screen surface can be completely cleaned even when the rotating drum screen rotates at a high speed, and the coating of solid molecules that cause clogging of the screen can be effectively peeled off from the screen surface.

At least one pressure fluid injection pipe having a plurality of pressure fluid injection ports or injection nozzles formed at predetermined intervals by extending the rotary washing mechanism in the axial direction of the rotary drum screen, and applying pressure to the injection pipe. In the case of using a pressure fluid supply mechanism for supplying a pressure fluid such as added water or air, the screen surface is washed with the pressure fluid ejected from the ejection port or the ejection nozzle.

When the injection pipe is positioned outside the rotary drum screen, the slit of the screen is backwashed by the injection fluid, and the injection fluid passing through the slit collides with the solid film laminated on the inner surface of the drum of the screen to form the same. Peel from the drum inner surface. When the injection tube is located inside the drum screen, the injection fluid breaks the laminated solid film on the inner surface of the drum and further cleans the slit surface. Further, when the injection tubes are installed both on the outside and inside of the rotating drum screen, the peeling and washing effects are doubled. At this time, the positions of the injection ports or the injection nozzles need to be arranged in a staggered pattern, for example, in order to prevent the inside and the outside from being opposed to each other.

When the rotary cleaning mechanism is driven to rotate in the same direction at the same rotation speed as the rotation speed of the rotary drum screen,
The same portion of the screen surface is always washed by the pressurized fluid ejected from the same ejection pipe. Either continuous or intermittent washing can be selected as needed.

When the rotary cleaning mechanism is driven to rotate in the same direction at a rotation speed different from the rotation speed of the rotary drum screen, when the rotation speed of the rotary cleaning mechanism is higher than the rotation speed of the rotary drum screen, that is, when the rotation of the rotary cleaning mechanism is advanced, There are cases where the rotation speed of the rotary cleaning mechanism is lower than the rotation speed of the rotary drum screen, that is, when the rotation is delayed.

In any case, the effect of peeling and backwashing can be exerted on the entire surface of the rotating drum screen.
That is, the position of the injection port or nozzle on each injection pipe is set to 1
By keeping the first, second, and third tubes slightly shifted in the axial direction, each injection port or nozzle advances on the circumference of the rotating drum screen faster or later than the rotating drum screen. The entire periphery of the rotating drum screen will always be cleaned.

When the rotary cleaning mechanism is driven to rotate in the direction opposite to the rotary drum screen, it is an effective backwash method when the rotary drum screen is rotated at a low speed depending on the nature of the workpiece. That is, in this case, a large number of cleaning rounds can be obtained for one rotation of the rotary drum screen, so that the effect of peeling and cleaning can be promptly improved. Even if the number of injection tubes is reduced to a small number such as one, a sufficient cleaning effect can be obtained.

When the rotary cleaning mechanism is configured to be rotatable about its central axis, that is, when the rotary cleaning mechanism is capable of rotating on its own, the injection fluid and the injection fluid from the injection port and the injection nozzle of the rotary cleaning mechanism are provided. Since the area to be diffused is widened and the surface to be cleaned of the screen is widened accordingly, the cleaning effect can be further enhanced. As a mode of rotation, a case where the rotary cleaning mechanism continuously rotates 360 ° or more,
It may reciprocate within a predetermined angle range, for example, 120 °.

The rotary washing mechanism can be constituted by a brush extending in the axial direction of the rotary drum screen. In this case, the structure can be simplified because a mechanism for supplying the pressure fluid is not required.

Similarly, when the rotary washing mechanism is constituted by a solid scraping plate or a tapping plate extending in the axial direction of the rotary drum screen, or a vibration generator attached to the rotary drum screen or another rotary washing mechanism, the pressure is similarly increased. Since a mechanism for supplying a fluid is not required, the structure can be simplified.

The above apparatus has a mechanism for rotating the rotary cleaning mechanism independently of the rotary motion of the rotary drum screen. However, without providing such an independent rotary drive mechanism, the rotary cleaning mechanism can be rotated by the rotary drum. In the device mounted on the rotating drum screen so as to rotate integrally with the screen, the same operation and effect can be obtained as in the above device in which the rotary cleaning mechanism is rotated in the same direction at the same rotating speed as the rotating speed of the rotating drum screen. It can be obtained with a simpler configuration.

[0033]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic sectional view showing in principle one embodiment of the cleaning device of the present invention. In this embodiment, the rotary cleaning mechanism of the cleaning device 1 comprises a plurality of backwash water injection pipes 3 disposed inside the rotary drum screen 2.

FIG. 2 is a perspective view showing a state in which the backwash water injection pipe 3 is disposed inside the rotary drum screen in this embodiment, excluding flange portions at both ends, and FIG.
FIG. 4 is a perspective view showing a backwash water supply mechanism for supplying backwash water to the apparatus.
FIG. 5 is a sectional view showing a part of the backwash water supply mechanism, and FIG.

In FIG. 1, a rotating drum screen 2
Has a well-known structure provided with a wedge wire screen 2a wound in a cylindrical shape as a screen surface, as shown in FIGS. The rotating drum screen 2 is housed in a casing 4, and rotating shafts 5, 6 provided at both ends of the rotating drum screen 2 have bearings 7, 6.
8 rotatably supported by the casing 4.
A pulley 9 is fixed to the rotating shaft 5 of the rotating drum screen 2 and is driven to rotate by a driving source (such as an electric motor) (not shown) via a belt (not shown).

As is apparent from FIG. 2, a plurality of backwash water injection pipes 3 are arranged inside the rotary drum screen 2 at predetermined intervals so as to extend in the axial direction of the rotary drum screen 2. In addition, a plurality of backwash water injection ports 3a are formed at predetermined intervals in each injection pipe 3. The injection port 3a of each injection pipe is formed such that its axial position is slightly shifted between the injection pipes adjacent in the circumferential direction.

One end of each of these injection pipes 3 is fixed to a disk-shaped flange 10 and is closed, and the other end is attached to a hollow short cylindrical hydraulic pressure chamber 11 which forms a part of a backwash water supply mechanism. It communicates with the inside of the hydraulic chamber 11.

A central tube 12 extending in the axial direction is rotatably supported on central shaft supports 15 and 16 via bearings 13 and 14 at the center of the rotary drum screen 2. The center tube 12 can rotate relative to the rotating drum screen 2 via the bearings 7 and 8.

The center tube 12 is divided into right and left parts in FIG. 1 by a partition wall 17, and the part on the left side in FIG. 1 functions as a supply pipe 18 for the raw material to be subjected to solid-liquid separation.

The raw material supply pipe 18 is formed with a plurality of raw material discharge ports 18a for supplying a raw material into the rotary drum screen.

The tube 12 is rotationally driven via a belt (not shown) and a pulley 19 by the same or a different driving source as the driving source of the rotary drum screen 2. In this embodiment, the rotary drum screen 2 and the center tube 12 are driven to rotate by the same drive source. By selecting a pulley 19 having a diameter larger than that of the pulley 9, the center tube 12 is moved from the rotary drum screen 2. Also rotate at low speed.

A flange 10 to which both ends of the backwash water injection pipe 3 are fixed and a hydraulic chamber 11 are fixed to the center pipe 12.

The right side of the partition wall 17 of the central pipe 12 is configured to function as a backwash water supply pipe charging pipe 21, and the water pressure chamber 11 is provided with a backwash water supply pipe as shown in FIGS. It is fixed to the central pipe 12 at the pipe charging pipe 21. The central part of the water pressure chamber communicates with the backwash water supply pipe 22 inserted into the backwash water supply pipe charging pipe 21 via the swivel joint 20.

One end of the backwash water supply pipe 22 is connected to a backwash water supply source (not shown), and is fixed to a frame (not shown) of the rotary drum screen 2. Therefore, the backwash water is supplied from the fixed backwash water supply pipe 22 via the swivel joint 20 and the hydraulic chamber 11 to each of the jet pipes 3 rotating.
Supplied to

In FIG. 1, reference numeral 23 denotes a casing 4
A drain outlet formed at the bottom of the casing for discharging the separated water after the solid-liquid separation, a solid outlet 24 for discharging the solid after the solid-liquid separation sent through the rotary drum screen 2, and a drain outlet 25 for the casing 4. This is a solids outlet formed below the solids outlet 24 of the rotary drum screen 2 at the bottom.

Next, the operation of the above embodiment will be described.
The raw material to be separated into solid and liquid is continuously discharged from the raw material discharge port 18a of the raw material supply pipe 18 into the rotary drum screen 2, and solid and liquid components are separated by centrifugal force in the rotary drum screen 2 rotating at high speed. Is separated, and the liquid component is removed from the wedge wire screen 2a of the rotary drum screen 2.
Is discharged in the direction of arrow A through the slit 2b formed between the two, and falls to the bottom of the casing 4 and is discharged from the discharge port 23 to the outside. The rotary drum screen 2 is conveyed rightward in the figure by a screw conveyor (not shown) and discharged to the outside through solids discharge ports 24 and 25.

As the solid-liquid separation by the rotary drum screen 2 progresses, the separated solids are deposited inside the wedge wire screen 2a as shown in FIG. 2b tends to cause clogging, but the injection port 3 of the inner backwash water injection pipe 3
When the backwash water is diffused and sprayed in the direction of arrow B from FIG. a, the deposited solid film f is broken and peeled off, the solid content is scattered in the rotary drum screen 2, and the clogging of the slit 2b is eliminated.

In the present embodiment, the backwash water injection pipe 3 is rotated at a lower speed than the rotary drum screen 2 as described above. As a result, each spray tube 3 rotates around the inner periphery of the rotating drum screen 2 to wash the opposing screen surface over the entire periphery, and peels off the solid coating f formed on that portion. The clogging of the slit 2b is eliminated. In addition, since the injection port 3 of each injection pipe 3 is formed so that the axial position thereof is slightly shifted between the injection pipes adjacent in the circumferential direction, the entire peripheral surface of the screen is evenly arranged in the axial direction of the screen. Washed.

The supply and injection of the backwash water may be performed continuously, but may be performed intermittently at predetermined time intervals according to the state of formation of the solid content coating f.

FIG. 6 shows another embodiment of the present invention.
In this embodiment, a backwash water injection nozzle 3c is formed as the backwash water injection pipe 3 instead of the injection port. Other structures are the same as those of the embodiment shown in FIGS.

FIG. 7 shows another embodiment of the present invention.
It is a perspective view which shows except the structure of the both ends of the rotating drum screen 2 and the backwash water injection pipe 3. In this embodiment, the backwash water injection pipe 3 is provided both inside and outside the rotary drum screen 2. The injection ports 3a of the inner injection pipe 3 and the injection ports 3a of the outer injection pipe 3 are arranged in a staggered manner.

FIG. 8 shows another embodiment of the present invention.
FIG. 2 is a perspective view showing a rotary drum screen 2 and a backwash water injection pipe 3 together with a flange 10 and a hydraulic chamber 11. In this embodiment, each backwash water injection pipe 3 is disposed outside the rotary drum screen 2 and a small gear 30 is fixed to each injection pipe 3 (for convenience, only one injection pipe 3 is provided). The small gear 30 is shown, but the other injection pipes 3 are the same.) The small gear 30 is fixed to the hydraulic chamber 11 by a mounting member (not shown) so as to rotate coaxially with the center pipe 12 ( (Only one part is shown). Therefore, each injection pipe 3 is rotatable in the direction of arrow C along the outer periphery of the rotary drum screen 2 and is also capable of rotating (self-rotating) around its own axis in the direction of arrow D.

FIG. 9 is a perspective view showing another embodiment of the present invention. In this embodiment, the rotary cleaning mechanism comprises a brush 41 implanted on a rod 40 extending in the axial direction of the rotary drum screen 2. A plurality of the brushes 41 are arranged at equal intervals along the outer peripheral surface of the rotary drum screen. Other configurations are the same as the embodiment of FIG. 1 except that the backwash water supply mechanism in FIG. 1 is not provided.

FIG. 10 is a perspective view showing another embodiment of the present invention. In this embodiment, the rotary washing mechanism comprises a solid scraping plate 50 extending in the axial direction of the rotary drum screen 2 instead of the brush. A plurality of the scraping plates 50 are arranged at equal intervals along the outer peripheral surface of the rotary drum screen. Other configurations are the same as those of the embodiment of FIG.

FIG. 11 is a perspective view showing another embodiment of the present invention. In this embodiment, the rotary washing mechanism includes a tapping plate 60 extending in the axial direction of the rotary drum screen 2 and a frame 61 fitted on both ends of the rotary drum screen 2.
And a plurality of protrusions 62 provided at predetermined intervals. A plurality of beat plates 60 are arranged at equal intervals along the outer peripheral surface of the rotary drum screen 2. Other configurations are the same as those of the embodiment of FIG. When the beating plate 60 rotates, vibration occurs each time the beating plate 60 gets over each projection 62, and the vibration removes the solid material film deposited on the screen surface to eliminate clogging of the slit.

FIG. 12 is a perspective view showing an embodiment similar to FIG. This embodiment is the same as the embodiment of FIG. 11 in that the beater plate 60 is used, but differs from the embodiment of FIG. 11 in that the rotary drum screen 2 is configured as an octagonal cylinder instead of the projection 62. Each time the beating plate 60 hits the corner of the octagonal cylinder and gets over it, vibration is generated.

FIG. 13 is a perspective view showing an embodiment similar to FIG. 11 and FIG. In this embodiment, the rotary cleaning mechanism is composed of vibration generators 71 respectively mounted on frames 70 fitted on the outer sides of both ends of the rotary drum screen 2. Known vibration generators can be used. In addition, as shown in FIGS. 1 to 9 and FIG. 14, the vibration generator may be additionally provided to the vibration generator having the backwash water injection pipe.

The backwash water injection pipe 3 in the embodiment of FIG.
Is configured to suction air instead of injecting backwash water using a nozzle provided with a nozzle 3c, and to suck and discharge a solid component constituting a solid film on a screen surface together with the air. It is also possible to do so.

The rotary drum screen is not limited to a cylindrical shape, but may be a polygonal cylindrical shape, a conical shape, or another shape.

In the above-described embodiment, the rotary drum screen is formed of a wedge wire. However, the present invention is not limited to this. The rotary drum screen is formed of a circular or other wire screen, a perforated plate, a wire mesh, or another filtering material. May be.

The arrangement direction of the rotating drum screen is not particularly limited, but may be vertical, horizontal or oblique.

FIG. 14 is a sectional view showing in principle an embodiment in which the backwash water injection pipe 3 is mounted so as to rotate integrally with the rotary drum screen 2 without providing an independent rotation drive mechanism. 13, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. 13 differs from the embodiment of FIG. 1 in that the rotary drum screen 2 is fixed to the center tube 12, and the rotary drum screen 2 and the injection tube 3 rotate integrally.

[0063]

As described above, according to the present invention, the rotary cleaning mechanism disposed at least on either the outside or the inside of the screen surface is rotated by the rotary drive mechanism independently of the rotation of the rotary drum screen. It is rotationally driven in the circumferential direction along the surface. Therefore, the rotational speed of the rotary cleaning mechanism is set to an optimal rotational speed for cleaning the screen surface in accordance with various conditions such as the operating conditions of the rotary drum screen and the conditions of the liquid to be treated to be solid-liquid separated. By rotating the rotation drive mechanism, the screen surface can be completely cleaned even when the rotating drum screen rotates at a high speed, and the coating of solid molecules that cause clogging of the screen can be effectively peeled off from the screen surface.

Also, by constructing the rotary cleaning mechanism so as to be rotatable about its central axis,
The range in which the spray fluid from the spray port and the spray nozzle of the rotary cleaning mechanism is diffused is widened, and the surface to be cleaned of the screen is accordingly widened, so that the cleaning effect can be further enhanced.

A brush for extending the rotary washing mechanism in the axial direction of the rotary drum screen, a solid scraping plate or a combination of a striking plate and a projection, or a combination of a striking plate and a corner of a polygonal cylindrical screen or a vibrator. , The structure can be simplified because a mechanism for supplying the pressure fluid is not required.

According to one aspect of the present invention, the rotary cleaning mechanism is attached to the rotary drum screen so as to rotate integrally with the rotary drum screen without providing an independent rotary drive mechanism. The same operation and effect as in the case where the screen is rotated in the same direction at the same rotation speed as the screen can be obtained with a simpler configuration.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of the present invention in principle.

FIG. 2 is a perspective view showing a piping state of a rotary drum screen and a backwash water injection pipe of the embodiment.

FIG. 3 is a perspective view showing a backwash water supply mechanism in the embodiment.

FIG. 4 is a sectional view showing a part of a backwash water supply mechanism.

FIG. 5 is a cross-sectional view for explaining a cleaning operation of the screen.

FIG. 6 is a perspective view showing a backwash water injection pipe used in another embodiment of the present invention.

FIG. 7 is a perspective view showing another embodiment of the present invention.

FIG. 8 is a perspective view showing another embodiment of the present invention.

FIG. 9 is a perspective view showing another embodiment of the present invention.

FIG. 10 is a perspective view showing another embodiment of the present invention.

FIG. 11 is a perspective view showing another embodiment of the present invention.

FIG. 12 is a perspective view showing another embodiment of the present invention.

FIG. 13 is a perspective view showing another embodiment of the present invention.

FIG. 14 is a sectional view showing still another embodiment of the present invention.

[Explanation of symbols]

 2 rotating drum screen 3 backwash water injection pipe 3a injection port 4 casing 18, 19 rotation drive mechanism 22 backwash water supply pipe 23 drain port 24, 25 solid content discharge port

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B01D 33/44-33/56

Claims (1)

(57) [Claims] 1. A rotary cleaning mechanism, which is rotatably arranged in a circumferential direction along at least one of an outer side and an inner side of a screen surface as viewed from a rotation axis of a rotary drum screen. and a rotation drive mechanism that can be rotational movement independently of the rotary motion of the rotary drum screen mechanism, the rotary cleaning mechanism, the rotary de
It extends in the axial direction of the ram screen and
At least one formed with a force fluid jet or jet nozzle
Pressure fluid injection tubes, wherein the pressure fluid injection tubes are
What is the rotary motion of the rotary drum screen of the rotary cleaning mechanism?
In addition to the independent rotary movement, the pressure fluid injection tube itself
A rotating drum screen cleaning device rotatable about a central axis of the rotary drum screen.