JPH042128B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a dust removal device for removing dust from seawater or river water, and in particular, to a dust removal device for improving water flow through a screen caused by dust adhering to the screen. Regarding equipment.

[Conventional technology]

Conventionally, dust removal devices have generally been widely used in industrial water canals and waterways for intake of cooling water in power plants and the like. The most well-known type of dust removal device has a link chain on both sides of the waterway, and each link of the link chain has a screen made of bar screen or wire mesh perpendicular to the water flow direction or at a predetermined angle of inclination. The structure is such that the screen is erected with a screen, and by rotating the screen, the dust attached to the screen is removed from the waterway.

5 and 6 show an example of a conventional dust removal device, in particular, FIG. 5 is an overall schematic view, and FIG. 6 is a detailed sectional view a and a front view b of a screen frame having a bucket portion.

As shown in the figure, this dust removal device has an upper sprocket wheel 1 installed at the top of the waterway and a lower sprocket wheel 2 installed at the bottom of the water, and an endless link chain 3 is mounted on these. has been done. The link chain 3 is provided with a screen frame 4 having a bucket section attached to its lower part for storing captured garbage. This screen frame 4
The upper sprocket wheel 1 is adapted to be rotated in order to move it around, and for this purpose a chain wheel 7 is connected via a transmission chain 6.
In FIG. 5, reference numeral 8 indicates the axis of the upper sprocket wheel 1, 9 indicates a guide plate for guiding the dust to the trough 10, 11 indicates the housing of the dust removal device, 12 indicates a water flow path, and arrow F indicates the direction of water flow.

Further, as shown in FIG. 6, the screen frame 4 is attached to each pitch of the link chain 3, and a screen body 14 made of a wire mesh or a large number of bar members arranged in the shape of a plow is attached to this. There is. The screen main body 14 is a member that faces the flowing water, blocks the flow of dust, etc. in the flowing water, collects it, and scoops it upward by the link chain 3 by driving. An upper beam 15 is provided at the upper end of the screen body 14, and this upper beam 1
5 is a pipe having a suitable diameter according to the width of the waterway, and the center thereof is set to be located at the center of the roller 3b of the link chain 3, and the pipe is connected to the The screen body 14 is integrally fixed. Further, a lower beam 17 having a U-shaped cross section is provided at the lower end of the screen main body 14, and this lower beam 17 connects to the upper beam 15 of the screen frame 4 adjacent to the lower part of the lower beam 17.
The screen main body 14 is integrally fixed via a mounting plate 18 which is provided so as to rotatably cover the upper part of the screen body and which projects from the upper part of the mounting plate 18 . A side plate 19 is provided to hold the side edge of the screen body 14, and this side plate 19 has a width wider than the link width of the link chain 3, as shown in FIG. 6a,
Moreover, it is integrally fixed to the left and right end surfaces of the upper beam 15 and the lower beam 17, respectively. In other words, the side plate 19, the upper beam 15, and the lower beam 17 form a frame (screen frame 4) that holds the screen body 14. This screen frame 4 is attached to the link chain 3 by fixing its side plate 19 to the side surface of the link 3a with bolts 20. Further, a garbage bucket 21 is provided on the lower beam 17 so as to diagonally cover the lower front part of the screen body 14, and its left and right ends are integrally fixed to the side plate 19 via a support plate 22. has been done.

In addition, in FIG. 5, 23 is a backwashing spray pipe placed on the back side of the screen body 14 which has turned inverted and downward via the upper sprocket wheel 1, and sprays water onto the back side of the screen body 14. This is to detach and remove adhering dust.

According to such a dust removal device, the dust and the like floating in the flow are first blocked from flowing by the screen body 14, and are scooped up by the dust bucket 21 as the link chain 3 rises, and the dust bucket 21 is further It rises, then reverses at upper sprocket wheel 1 and turns downward. As a result, the garbage remaining in the garbage bucket 21 falls and is discharged into the trough 10 via the inclined surface of the garbage bucket 21 and the guide plate 9.

[Problem to be solved by the invention]

By the way, in recent years, as the water intake has increased, the width of the waterways has become wider, and the amount of debris floating in the waterways has tended to increase. The screen body 14 gradually becomes clogged due to the amount of dust exceeding the processing capacity of the device, and finally, it becomes impossible to secure sufficient water flow, and the water level difference between the front and rear of the dust removal device suddenly increases. I was invited. The processing capacity of the dust removal device is determined by the amount of dust that can be scooped up depending on the capacity of the screen body 14 and the garbage bucket 21 and their operating speed, but in reality, the amount of dust that can be scraped up is determined by the capacity of the screen body 14 and the garbage bucket 21, but in reality, the amount of dust that can be scooped up is determined by the amount of dust that can be scooped up by the capacity of the screen body 14 and the garbage bucket 21. As a result, an abnormal water level difference has occurred on the screen, and the plant is currently unable to operate.

For this reason, if the water level difference before and after the dust removal device exceeds a certain value, the pressure of the flowing water applied to the screen body 14 and screen frame 4 will become excessive, so measures such as limiting the amount of water taken are unavoidable. was.
However, if such a situation occurs during a power demand period, the power supply at the power plant will not be able to keep up with the demand, resulting in a power outage, which is a serious public abnormality.

The present invention has focused on the above-mentioned conventional problems, and aims to provide a dust removal device having a screen structure that has a high dust adhesion rate and is less likely to become clogged.

[Means to solve the problem]

In order to achieve the above object, a dust removing device according to the present invention is provided with a mesh screen that is moved around at least a pair of upper and lower wheels, and is installed across a waterway in a semi-submerged state. , the mesh screen has a corrugated cross section so that unevenness occurs in the direction of water inflow. In a second aspect, bar screens are provided on the front surface of the mesh screen at half-period intervals corresponding to the corrugated concave and convex portions. Furthermore, thirdly, the front surface of the bar screen has an uneven structure.

[Effect]

According to the first configuration, since the mesh screen has a corrugated shape, the area of dust adhesion increases compared to the case of a flat screen. Therefore, the amount of attached dust can be increased by the increased area, thereby improving the dust removal ability. Further, the dust adhering to the mesh screen concentrates on the uneven surface, particularly in the concave portions, and becomes difficult to adhere to the convex portions due to the action of running water. This prevents the convex portion from being clogged with debris, and prevents water flow from being blocked due to clogging.

According to the second configuration, a bar screen is further installed in front of the net-type screen corresponding to the uneven portion every half period of the net-type screen, so water matrix etc. are collected in advance on the bar screen and the bar screen is removed from the net-type screen. By reducing the area that adheres to the mold screen, the rate of dust adhesion can be increased. In addition, according to the third configuration, even if there is adhesion due to the bar screen, a step is formed at the tip of each bar, resulting in an uneven arrangement, which causes a guiding effect of the dust to the recessed part of the mesh screen, resulting in high dust removal. able to perform its functions.

〔Example〕

Hereinafter, specific embodiments of the dust removal device according to the present invention will be described in detail with reference to the drawings. Note that the same numbers are given to the same components as in the conventional example described above, and explanations thereof will be omitted.

FIG. 1 is a perspective view of a main part of a screen to be applied to a dust removal device according to an embodiment. This screen is a mesh screen 30, and the screen frame 4
The screen main body 32 held by the screen body 32 is formed of a filter net, and the filter net is not a flat net but a corrugated net, and this is attached to the screen frame 4. That is, the screen frame 4 is formed by an upper beam 15 (a channel material with a U-shaped cross section in the embodiment), a lower beam 17, and a side plate 19 (not shown), and the screen body 32 is surrounded by the frame. Although it is installed,
As shown in the figure, the screen body 32 has a corrugated shape such that unevenness is formed on the surface facing the water flow direction F by waving along a direction perpendicular to the direction of movement by the link chain 3 (arrow A). Molded and attached. In order to attach this mesh screen 30 to the screen frame 4, a mounting plate is fixed around the screen body 32, and the mounting plate 34 to the upper beam 15 and lower beam 17,
36 is formed in a corrugated shape similar to the screen main body 32, and is fixed by being connected with screws or the like at the abutting portions to the respective beams 15 and 17. Also, the screen body 3
Since the side edge of 2 is a straight edge, the corresponding side plate 19 is formed of a straight member as in the conventional case,
What is necessary is to connect it to the link 3a of the link chain 3.

A mesh screen 3 formed in such a waveform
The operation of the dust removal device using 0 is as follows. When this dust removal device is installed in a waterway, the screen main body 32 will have irregularities on the portion facing the water flow direction. When the water matrix 38 reaches such a screen body 32 together with the flowing water, some of it directly reaches the concave portions, while others reach the convex portions, as shown in FIG. However, the water matrix etc. that reached the convex part 38
The dust moves along the slope from the convex part to the concave part by the action of flowing water, and these dust particles are concentratedly collected in the concave part. Therefore, the convex portions are less likely to be clogged due to adhesion of dust, and as a result, the convex portions of the screen main body 32 allow water to pass through easily, and the resistance component is reduced.

By the way, by making the screen body 32 wave-shaped, the water flow area per unit projected area becomes 1.5 times as large as that of the conventional flat mesh screen body 14. Therefore, the dust collection area increases and the degree of clogging (%) due to the same amount of dust is 1/1.5.
become. Therefore, it is possible to improve the dust collection efficiency while significantly reducing the water flow resistance. FIG. 3 compares the head loss caused by the dust removal device using the conventional screen body 14 and the dust removal device according to the present embodiment using the corrugated screen body 32. Conventional dust removal equipment has a clogging rate of 90%.
In this example, the water level difference before and after the dust removal device was 1.386 m (characteristic line P), but in this example, the degree of clogging is 60% for the same amount of dust, and the water level difference is 0.086 m (characteristic line P). Q).

Therefore, according to this embodiment, it is possible to increase the efficiency of collecting dust while lowering water flow resistance, and in particular, even when water matrix, seaweed, vinyl sheets, etc. are attached, the collection is concentrated in the recesses of the uneven surface. Since it is possible to prevent the particles from adhering to the convex portions, the adhesion area can be reduced.

Next, FIG. 4 shows an enlarged sectional view of the screen portion of the dust removal device according to the second embodiment. This second embodiment differs from the first embodiment in that a bar screen 40 is further arranged in front of the screen main body 32. In other words, the screen body 3 formed into a corrugated shape
Screen bar 40A every half period of the wave period of 2,
40B, and in particular, each screen bar 4 is installed corresponding to the convex portion and the concave portion of the screen body 32.
0A and 40B are installed. The screen bars 40A, 40B are flat plates, and are arranged so that the plate surfaces are along the flowing water direction.
It is fixed and attached to 7. The rear ends of the screen bars 40A, 40B are joined to the screen body 32, the tips are directed upstream of the waterway, and the front ends of the screen bars 40A, 40B are made to have different lengths, thereby making the front surface of the bar screen 40 itself uneven. I'm trying to make it happen. Therefore, the screen bar 40A with a small width and the screen bar 40B with a relatively large width are alternately arranged on the screen main body 3.
The screen bar 40A is mounted so as to be perpendicular to the screen surface corresponding to the convex portion and the concave portion of the second screen bar 40A, and in this state, the tip of the screen bar 40A is set to protrude more forward than the tip of the other screen bar 40B.

According to the second embodiment, since the bar screen 40 having an uneven surface is installed on the front surface of the uneven screen main body 32, damage to the mesh screen 30 due to the inflow of wood chips etc. can be prevented. In addition, it is possible to capture large water bodies etc. by the bar screen 40 and prevent them from directly adhering to the mesh screen 30, thereby reducing the area of adhesion to the mesh screen 30. can do. In addition, since the front surface of the bar screen 40 itself is uneven, and each screen bar 40A, 40B is installed corresponding to the unevenness of the screen main body 32, even if there is dust that has passed through the bar screen 40, this The screen bars 40A and 40B act as guides to the recesses of the screen body 32 and collect the dust in a concentrated manner in the recesses of the screen body 32, so that the so-called separate collection on the mesh screen 30 is performed. As a result, the convex portions of the mesh screen 30 are always free from clogging, and more effective dust collection and water permeability can be ensured.

In addition, in the above embodiment, when the screen body 32 of the net type screen 30 is formed into a wave shape, it is formed in a direction perpendicular to the moving direction by the link chain 3, so that the dust adhering to the recesses is moved to the lower part along the recesses. Although the waves are more likely to fall into the bucket 21, the direction in which the waves are formed is not limited to the example and can be formed in any direction. It is also possible to form a waveform in the vertical and horizontal directions in which concavities and convexities are formed in a so-called matrix shape, although molding is somewhat difficult.

Further, in the second embodiment, the bar screen 40 has steps formed at the tips of the screen bars 40A and 40B so that unevenness is formed on the front surface, but this may be done by aligning the tips. can. Needless to say, this ensures the ability to collect wood chips and the like in advance and prevent damage to the mesh screen 30.

〔Effect of the invention〕

As explained above, according to the present invention, since the mesh screen is formed in a corrugated shape, it is possible to improve the dust collection efficiency by increasing the water flow area, and at the same time, it is possible to improve the water flow failure caused by clogging, and the dust removal This provides the effect of effectively preventing abnormal water level differences from occurring before and after the device. Further, by installing a bar screen with unevenness on the front surface of the corrugated mesh screen, it is possible to prevent damage to the mesh screen and to reduce the area on which dust adheres to the mesh screen. Furthermore, by forming the unevenness on the front surface of the bar screen, it is possible to obtain the effect that water flow resistance can be further reduced while maintaining high dust collection efficiency.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the essential parts of the mesh screen applied to the dust removal device according to the embodiment, Fig. 2 is an explanatory diagram of the state of dust collection by the mesh screen, and Fig. 3 is the main part perspective view of the mesh screen applied to the dust removal device according to the embodiment. A comparison diagram of the properties of hedrus by a net-type screen, FIG. 4 is a partial cross-sectional view of the screen applied to the dust removal device according to the second embodiment,
FIG. 5 is an overall sectional view of a conventional dust removing device, and FIG. 6 is a partially enlarged view of a screen frame of the same dust removing device, in which a is a side view and b is a front view. 4... Screen frame, 15... Upper beam, 1
7...Lower beam, 30...Mesh screen, 3
2...Screen body, 34, 36...Mounting plate,
40... Bar screen, 40A, 40B... Screen bar.

Claims (1)

[Scope of Claims] 1. In a dust removal device that is equipped with a net-type screen that is rotated around at least a pair of upper and lower wheels and that is installed across a waterway in a semi-submerged state, the net-type screen is connected to an inflow of water. A dust removal device characterized by having a wave-shaped cross section so that unevenness occurs in the direction. 2. A dust removal device characterized in that bar screens are provided on the front surface of the mesh screen at half-period intervals corresponding to the corrugated uneven portions. 3. The dust removal device according to claim 2, wherein the front surface of the bar screen has an uneven surface.