JPH0631195A - Wet classifier - Google Patents

Abstract

PURPOSE:To obtain a scraper bucket provided with a scraper blade on a drum and capable of efficiently dehydrating sand. CONSTITUTION:A scraper blade 19 is provided on a drum 15, a side plate 16 is furnished on one side, a side plate is also provided on the other side, and an outlet 18 is furnished to the side plate 16 facing the spiral impeller. The drum 15, scraper blade 19 and side plate 16 are made of a wire mesh or a perforated plate. Since the drum 15 is permeable to water, the water in the scraped sand is passed through the drum 15 and returned to a treating tank. As the scraper blade 19 is provided on the drum, the sand is retained and dehydrated over the long distance for a long time, and hence a succeeding dehydrator means is not needed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet classifier for classifying sand by mixing raw material water of sand containing mud, wood chips, etc., stirring the mixture to wash the sand, and more particularly, to a horizontal spiral impeller and a scraper. The present invention relates to a scraping bucket suitable for a wet classifier equipped with a lifting bucket.

[0002]

2. Description of the Related Art FIG. 11 is a schematic vertical sectional view of a conventional example. A spiral impeller 2 and a scraping bucket 3 are provided in the processing tank 1.
Are provided in common with the horizontal drive shaft 4. The scraping bucket 3 is provided with scraping blades on the inner side of a cylindrical drum whose outer circumference is a wire mesh or a perforated plate. A chute 8 whose upper end has entered the scraping bucket 3 is provided. The drive shaft 4 is supported by bearings 5 provided on both end walls of the processing tank 1, and the drive shaft 4 and the reduction motor 6 are connected by a chain transmission device 7. When the electric motor 6 is energized, the drive shaft 4 rotates via the chain transmission device 7, and the spiral impeller 2 and the scraping bucket 3 rotate. When the raw sand is poured into the treatment tank 1 together with the cleaning water, the water and the sand are stirred in the treatment tank 1 and the sand is washed and sent by the spiral impeller 2 in the direction of the arrow and lifted by the scraping bucket 3. The sand is sent out of the machine by a chute 8 which descends outward. This sand is the sand of the grain size that becomes the intended product sand. Then, the remaining muddy water containing lighter and finer sand overflows from the upper edge of the treatment tank 1.

The sand sent out of the chute 8 is sent out by the conveyor 11.

A belt conveyor is used as the conveyor 11. The sand transferred from the chute 8 to the conveyor 11 has a large water content, and if it is transferred as it is, a large amount of water is sent to the product accumulation site, which makes wastewater treatment difficult. Therefore, a vibration conveyor equipped with a device for exciting the belt conveyor is often used.

The chute 8 is conventionally fixed. The above-mentioned bearing 5 is substantially large in size, is arranged on the outlet side of the scraping bucket 3, and the frame of the bearing 5 also comes in. Therefore, the width and inclination angle of the chute 8 that receives the sand that has been scraped inside the scraping bucket 3 and discharges it outside the machine are naturally limited. Therefore, a method has been proposed in which the vibrating screen 10 is directly inserted into the scraping bucket 3 as shown in FIG. 10 without using the chute 8. When such a vibrating conveyor and vibrating screen are not used, dehydrated trommel is used as the next step.

[0006]

Since the dehydration is not sufficient in the raking bucket having the raking blades on the inner circumference of the drum, the vibration conveyor or the vibration sieve is used, for example, as described above. If the inner circumference of the drum is provided with a scraping blade, the scraping blade separates water and the water-containing sand in the scraping blade falls just above the drum. Therefore, it is within a quadrant of the rotation angle of the scraping bucket that the water contained in the sand in the scraping blade is discharged after the water is removed, and the distance and time for discharging the sand from the scraping blade are short and large. Take out water. Therefore, when a vibrating conveyor is used, sand containing a large amount of water is sent to the vibrating conveyor, and the floating water W1 flows out and is drained as shown in FIG.
Since the water W2 accumulated at the bottom of a does not float and remains until the end, the water at the bottom of the conveyor belt 11a cannot be drained.

In the dewatering method using the vibrating screen 10, since the vibrating screen 10 must be horizontal or descended on the outlet side, the conveyor 11 is eventually required. Further, according to the vibrating screen 10, a part of the water in the sand floats on the sand and escapes from the lower porous plate. However, since the sand discharged from the scraping bucket 3 contains fine sand, the fine sand is clogged by the vibration in the gap formed between the coarse sand and the sand on the vibrating sieve 10, and the place where water escapes before the hole of the perforated plate. Disappears. Further, the vibrating screen 10 has a drawback that its ability changes when the vibration condition changes depending on the amount of product sand conveyed, and when the amount of conveyance increases beyond a proper amount, the product does not vibrate and the product sand is not discharged. is there. Dehydration with dewatering trommel requires a large device other than the wet classifier, increasing both the installation cost and the installation location.

Therefore, when a scraping bucket having a scraping blade on the outer circumference of the drum is used, the scraping blade is a perforated plate or a wire mesh, like the scraping bucket having a scraping blade on the inner circumference of the drum. The bucket has a blade on the outer circumference of the drum, but the distance from when the blade leaves the water surface of the processing tank until the sand in the blade is discharged is long, and the dehydration effect is The dewatering performance of the transportation means, which is large and is connected to the downstream side of the scraping bucket, may be relatively low. However, in the wet classifier equipped with the scraping blades on the outer circumference of the drum, the sand discharged from the scraping bucket still contains a large amount of water, and it is inevitable that the subsequent device performs dewatering.

The present invention has solved the above-mentioned problems and is effective in dehydrating sand hydrated with muddy water containing fine sand.
An object of the present invention is to provide a wet classifier equipped with a scraping bucket that does not require a subsequent dehydrating means and can be provided with a small size.

[0010]

A first aspect of the present invention is a horizontal spiral type wet classifier having a horizontal axis of a spiral impeller for extrusion and a scraping bucket housed in a processing tank. The bucket is a wet classifier characterized by having a container-shaped scraping blade having the drum as one of the container walls on the outer peripheral side of a cylindrical drum, and the drum and the scraping blade having water permeability.

The second invention of the present invention is the wet classifier according to the first invention, characterized in that the cylindrical drum or the scraping blade is made of a perforated plate.

A third invention of the present invention is the wet classifier according to the first invention, characterized in that the cylindrical drum or the scraping blade is made of wire mesh.

A fourth aspect of the present invention is characterized in that the cylindrical drum has side plates on both sides on the outer peripheral side, and the side plate facing the spiral impeller is provided with an inlet. The wet classifier according to any one of the inventions to the third invention.

A fifth aspect of the present invention is characterized in that the spiral impeller and the raking bucket are separated from each other.
The wet classifier according to any one of the first to fourth inventions.

A sixth aspect of the present invention is characterized in that the spiral impeller and the raking bucket are rotatably supported, and the spiral impeller and the raking bucket have driving means capable of rotating at different rotational speeds. The wet classifier according to any one of the first to fifth inventions.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

[Embodiment 1] FIG. 1 is a front view of the scraping bucket 3 as seen from the side of the spiral impeller in a direction perpendicular to the axis, and FIG.
FIG. 3 is a partial perspective view of FIG. 1. The boss 12 and the bucket car frame 13 fixed to the drive shaft 4 are the boss 12 and the bucket car frame 13.
Are connected by radial arms 14 which are fixed by welding. The bucket frame 13 is a hollow cylindrical drum 15
One of the side plates 16 having ring-shaped side plates 16 and 17 on both axial sides faces the spiral impeller 2 and has a sand inlet 18 for sending sand from the spiral impeller 2. The circumferential direction is evenly arranged. Scrape blades 19 are fixed to the outer periphery of the drum 15 and the opposing surfaces of the side plates 16 and 17 in the circumferential direction. The feed port 18 is arranged between two adjacent scraping blades 19. Further, the scraping blade 19 has its tip aligned with the outer circumference of the side plates 16 and 17, and the tangent line of the outer circumference of the side plates 16 and 17 passing through the point P at the tip and the rake portion 19a having a rake angle θ and the tangent line and the rake. It has a built-in plate portion 19b which forms an angle larger than the angle θ and forms a built-in portion that contains sand.

The inlet 18 is provided in the side plate 16 at a position close to the back of the built-in plate portion 19b of one scraping blade 19, and the scraping blade 19 adjacent to the one scraping blade 19 is provided.
Is separated from the built-in plate portion 19b. Further, it is provided on the outer peripheral side far away from the drum 15. Spiral impeller 2
When the scraping buckets 3 have the same diameter, the radial end surfaces of the blades of the spiral impeller 2 face the area of the inlet 18. It should be noted that the side plate 17 may be provided with the inlet port 18 similarly to the side plate 16.

In the above description, the drum 15 and the side plates 16 and 17 constituting the bucket car frame 13 are perforated plates or wire nets,
The scraping blade 19 is a perforated plate or a wire net. When the bucket car frame 13 and the scraping blades 19 are wire nets, the wire nets are supported by a frame material (not shown).

As can be seen from the above, the scraping blade 1
Reference numeral 9 denotes a container, and the drum 15 of the bucket car frame 13
The side plates 16 and 17 also serve as the container wall of the scraping blade 19, whereby the container is water permeable in all directions and the scraping bucket 3 has a simple and strong structure.

FIG. 3 is a schematic vertical sectional view showing the entire wet classifier,
4 is a plan view and FIG. 5 is a side view. A spiral impeller 2 and a scraping bucket 3 are provided in the processing tank 1 with a horizontal drive shaft 4 in common. The spiral impeller 2 and the scraping bucket 3 are submerged near the lower half in the liquid whose liquid level is fixed at the upper edge of the processing tank 1, respectively. A conveying means 21 such as a chute or a conveyor is arranged on the outer circumference of the scraping bucket 3 so that its inlet side is close to the outer circumference.

The drive shaft 4 is supported by bearings 5 provided on both end walls of the processing tank 1, and the drive shaft 4 and the reduction motor 6 are connected by a chain transmission device 7. When the electric motor 6 is energized, the drive shaft 4 rotates via the chain transmission device 7, and the spiral impeller 2 and the scraping bucket 3 rotate. When the raw sand is poured into the treatment tank 1 together with the wash water and poured, the water and the sand are agitated in the treatment tank 1 so that the sand is washed and sent by the spiral impeller 2 in the direction of the arrow, and then the scraping bucket 3 is used. The lifted sand is sent out of the machine by the transportation means 21.
This sand is the sand of the grain size that becomes the intended product sand. Then, the remaining muddy water containing lighter and finer sand overflows from the upper edge of the treatment tank 1.

Consider the action of the scraping bucket 3. In the scraping bucket 3, after the scraping blade 19 is submerged from the liquid surface of the processing tank 1, the opening of the scraping blade 19 is directed obliquely downward until it approaches the bottom of the processing tank 1 and scratches the liquid. Since it proceeds, the sand at the bottom of the processing tank 1 is not captured. Raising blade 1
When 9 approaches the bottom of the processing tank 1, the sand sent by the spiral impeller 2 to the bottom of the processing tank 1 is scooped up and the sand is sent from the inlet 18 into the bucket by the water flow generated by the spiral impeller 2. , Drum 15, side plate 16,
17. Since the raking blade 19 is water permeable, the raking blade 19 stores sand on the internal built-in plate portion 19b, advances through the liquid, and separates from the water surface 22 of the processing tank 1 in FIG. As shown in the drawing, the sand from which the scraping blades 19 come to the position 19-1 moves to the back side where the drum 15 exists, and the water in the sand moves to the side plate 1.
6, 17, through the perforated plate constituting the scraping blade 19,
The water in the scooped sand is not only dehydrated but also drum 1
The water is also drained from the portion 15-1 facing the scraping blade 19 of No. 5 and forming a part of the container. The same state continues until the scraping blade 19 passes the uppermost position, and the same action is continued. The rotation angle of the raking blade 19 to the top after water is taken off is 90.
Over degree. And the raking blades 19 are the raking buckets 3.
Around the top of the blade, and the built-in plate portion 19b of the scraping blade 19
Begins to lean downwards. As the scraping blade 19 advances, the sand on the outer peripheral side of the drum 15 moves to the back surface of the scraping blade 19, and the conveying means 21 lifts the sand.
When approaching, the back surface of the built-in plate portion 19b further descends outward, so that the sand falls onto the carrying means 21. The raking blade 19 moves from the uppermost position of the raking bucket 3 to the conveying means 2
While moving to the vicinity of 1, the water in the sand is drained and the water content is lowered. Since the drum, which is the conventional bucket having the scraping blades on the outer circumference of the drum, has no water permeability, it is dehydrated from the scraping blades 19 while the scraping blades 19 move to the vicinity of the transport means 21 after separating water. The water that came out flowed toward the scraping blade at the lower position next to the scraping blade 19 and flowed into the sand held by the scraping blade at the lower adjacent position to increase the water content. Since this is eliminated by making the drum 15 water-permeable, the dehydration performance is remarkably improved.

Further, comparing the rotation angle between the scraped bucket having the scraping blade inside the drum and the scraping bucket 1 of the present invention from the separation of the scraping blade to the discharging of sand, the inside of the drum is compared. The rotation angle of the scraping bucket provided with the scraping blades is usually about 45 ° within 90 °, whereas it is about 135 ° in the scraping bucket of the present invention. In the scraping bucket equipped with scraping blades on the inside of the drum, after the scraping blades have taken off the water, the drum has no draining action, but in the present invention, the draining action is performed because the drum 15 is made water-permeable.

In the test example, in order to obtain sand having a grain size of 5 mm or less, a drum and a raking blade were used with a perforated plate having a hole diameter of 13 mm, and a bucket having a raking blade inside a conventional drum was used. It was found that there is about 3 times the dehydration performance as compared with.

[Second Embodiment] In the first embodiment, the impeller 2 and the scraping bucket 3 are spirally connected to each other. Therefore, the solid-liquid mixture in a state in which the raw material and the wash water sent from the spiral impeller 2 are effectively sent to the scraping bucket 3. However, the crushed stone of the raw material is mixed with wood chips, vegetation and the like, and these float on the surface of the water as suspended matter, and the mud and fine sand that overflow from the overflow edge 1a of the treatment tank to the gutter 24 (see FIG. 4) are collected. Although a part of it is prevented from being discharged together with the contained slurry and the like and entering the product sand, the axial fluid flow generated by the spiral impeller 2 is submerged in the treatment tank 1 of the spiral impeller 2. The flow is toward the scraping bucket 3, so that the scraping bucket 3 scoops up suspended matter. For this reason, wood chips and plants are mixed with the product sand. The purpose of the present embodiment 2 is to prevent floating substances such as wood chips and vegetation in the treatment tank 1 from flowing into the scraping bucket 3 and discharging with the product sand.
Is.

The second embodiment is the same as the first embodiment as a whole, the same functional parts are designated by the same reference numerals, and the description thereof will be omitted. Only different parts will be described. As shown in FIG. 6, a space S is provided between the spiral impeller 2 and the scraping bucket 3. Further, on the water surface below the space S, there is provided a floating material blocking plate 25 which is slightly submerged so that floating material on the water surface does not move to the portion of the processing tank 1 in which the scraping bucket 3 is accommodated. The blocking plate 25 may extend over the entire width of the processing tank 1, but it may have a structure in which the blocking plate 25 is provided only at both ends and not in the central portion. If the spiral impeller 2 and the scraping bucket 3 are opened without the floating material blocking plate 25, the floating material enters the surface of the water in the drum 15 and floats there.

In the operating state of the apparatus, as shown in FIG. 7, on the water surface of the treatment tank 1, the spiral impeller 2 is rotated by the rotation of the spiral impeller 2 and the overflow edge 1a of the treatment tank 1 by the rotation of the spiral impeller 2. A mixture of water and sand flows between the scraping buckets 3 toward the bucket 3. Also during this time, the washing water is injected and overflows from the overflow edge 1a, and a part of the suspended matter is discharged together with the overflowed water. When the surface flow reaches the end of the spiral impeller 2, the suspended matter blocking plate 25 prevents the suspended matter from moving toward the scraping bucket 3.

If the floating material blocking plate 25 is not provided, the floating material flows to the scraping bucket 3 side, but the drum 15 is larger than the spiral impeller 2 and the overflow edge 1 as in this example (FIG. 7).
In the case of almost the same position as a, the drum 15 of the scraping bucket 3
It floats inside, and the water surface in the drum 15 is not scooped up with the product sand because it is not scooped up by the scraping blades. Further, if the floating material blocking plates 25 are provided only at both ends, even if the spiral impeller 2 and the raking bucket 3 have the same diameter, the floating material is not picked up by the raking blades 19, and the drum of the raking bucket 3 is 15 Floats after moving to the inner water surface.

[Embodiment 3] When the spiral impeller 2 and the scraping bucket 3 are provided on the drive shaft 4, the spiral impeller 2 and the scraping bucket 3 have the same rotational speed. When the amount of raw material processed per unit time, the properties of the raw material, etc. differ, the speed of rotation of the spiral impeller 2 that provides the necessary stirring and feeding of the raw material containing sand and the processing that should be discharged by the scraping bucket 3 In some cases, the rotation speed required to discharge the product is not compatible. Corresponding to these, the third embodiment aims at obtaining a wet classifier capable of always matching the capabilities of the spiral impeller and the scraping bucket.

8 and 9 show the third embodiment. The entire configuration is the same as that of the second embodiment, and the same functional portions as those of the second embodiment are denoted by the same reference numerals, the description thereof is omitted, and different portions will be described. The spiral impeller 2 is fixed to the shaft 4a, and the shaft 4a
Is rotatably supported by a bearing 5a fixed to the processing tank 1 and a bearing 29 fixed to a horizontal member 32 provided on the outer wall of the gutter 24 on both sides of the processing tank 1. The shaft 4 a is driven by the reduction motor 6 via the chain transmission device 7. The scraping bucket 3 is fixed to a shaft 4b which is concentric with the shaft 4a, and the shaft 4b
Is rotatably supported by bearings 5b and 31. Bearing 5
b is fixed to the processing tank 1, and the bearing 31 is the horizontal member 32 described above.
It is fixed to. The shaft 4b is connected to the reduction motor 27 via a chain transmission device 28. If the reduction motors 6 and 27 are variable speed motors, the rotation speeds of the spiral impeller 2 and the scraping bucket 3 are selected so that the capacities of the spiral impeller 2 and the scraping bucket 3 match according to the properties of the raw materials and the throughput. it can.

Incidentally, in order to rotatably support the spiral impeller 2 and the scraping bucket 3, respectively, in FIG.
The spiral impeller 2 may be fixed to the shaft 4, and the scraping bucket 3 may be rotatable with respect to the shaft 4, and a driving means for the scraping bucket 3 may be provided. Conversely, the scraping bucket 3 may be fixed to the shaft 4 and the shaft 4 may be rotated. On the other hand, the spiral impeller 2 may be rotatably supported and drive means for the spiral impeller 2 may be provided. In this embodiment, of course, the spiral impeller 2 and the scraping bucket 3 may be arranged in close proximity to each other.

In the embodiment, the bearing 5 for discharging the sand to the outer peripheral side of the scraping bucket 3 receives almost no water, but in FIG. 3, a partition wall fixed to the processing tank 1 is provided between the scraping bucket 3 and the bearing 5. By providing 23, even a slight splash of water is not applied to the bearing 5, and the bearing 5 does not need to consider waterproofing.

In each of the embodiments, the side plate for forming the scraping blade 19 in a container shape is the ring-shaped side plate 1 of the drum frame 13.
Since 6 and 17 are also used, the strength and rigidity of the raking bucket 3 can be increased, and the pitch between the raking blades 19 can be reduced.

Although the scraping blade 19 of the embodiment has a scraping function together with the side plates 16 and 17 of the drum frame 13, the scraping blade has a scooping portion 19a and a built-in plate portion 19.
Alternatively, side plates may be individually provided on both sides in the axial direction of the plate member in the radial direction forming b, and the side plates may be attached to the outer periphery of the drum 15 as a container.

In the embodiment, since the scraping bucket has a larger diameter than the spiral impeller, it is easy to store sand in the scraping bucket portion of the processing tank, but the same diameter may be used as described above.

[0037]

According to the present invention, in the moisture classifier equipped with the spiral impeller and the scraping bucket, the scraping blades are arranged on the outer peripheral side of the drum so as to have water permeability in all directions. The distance that the sand is held from the water of the raking blade to the transportation means is about three times that of the raking bucket equipped with the raking blade inside the drum, and the distance is long. At the same time, the water discharged from the sand returns to the processing tank through the drum, so that the dewatering performance can be remarkably enhanced and the dewatering can be completed only by the scraping bucket. (2) Even if scooping up fine sand with a scraping bucket, it can be dehydrated and discharged, and the sand can be used as a product by escaping it together with the water that overflows from the processing tank. (3) A dewatering trommel is separately provided so that an installation place and cost are not required, and a dewatering conveyor having special dewatering performance is not required to use a vibrating sieve as a transportation means. There is no trouble associated with a high-performance transportation means, and it is no longer necessary to dispose the transportation means long for dehydration. Therefore, the cost is low. (4) The bearing can be simplified because almost no water is applied to the bearing. (5) If the scraping bucket is made symmetrical with respect to the axial direction, sand can be discharged by selecting it on either side. (6) When the spiral impeller and the scraping bucket are separated from each other, the suspended solid does not enter the scraping bucket, and the suspended solid is not scooped together with the product sand, so that the quality of the product sand can be improved. (7) If it is possible to rotate the spiral impeller and the raking bucket at different speeds, the speed ratio of these can be changed, and both the spiral impeller and the raking bucket will have optimum rotation speeds depending on the type of raw material and the throughput. Can be obtained.

[Brief description of drawings]

FIG. 1 is a front view showing a partial cross section of a raking bucket according to a first embodiment of the present invention.

FIG. 2 is a perspective view of FIG.

FIG. 3 is a side sectional view of an embodiment of the wet classifier of the present invention.

FIG. 4 is a plan view of FIG.

5 is a cross-sectional view perpendicular to the axis of the position of the scraping bucket of FIG.

FIG. 6 is a side sectional view of a second embodiment.

FIG. 7 is a plan view of FIG.

FIG. 8 is a side sectional view of a third embodiment.

9 is a cross-sectional view taken along the line AA of FIG.

FIG. 10 is a vertical cross-sectional view of a wet classifier using a vibrating conveyor as a discharge device.

FIG. 11 is a vertical cross-sectional view of a conventional wet classifier.

FIG. 12 is a sectional view of a belt for illustrating the operation of the dehydration conveyor.

[Explanation of symbols]

 1 Processing Tank 2 Spiral Impeller 3 Raking Bucket 13 Bucket Frame 15 Hollow Cylindrical Drum 17 Raking Blade

Claims (6)

[Claims] 1. In a horizontal spiral type wet classifier having a horizontal shaft-extruding spiral impeller and a scraping bucket housed in a processing tank, the scraping bucket has a drum on the outer peripheral side of the cylindrical drum. A wet classifier having a container-shaped scraping blade as one of the container walls, wherein the drum and the scraping blade have water permeability. 2. The wet classifier according to claim 1, wherein the cylindrical drum or the scraping blade is made of a perforated plate. 3. The wet classifier according to claim 1, wherein the cylindrical drum or the scraping blade is made of wire mesh. 4. The cylindrical drum has side plates on both sides on the outer peripheral side, and a side plate facing the spiral impeller is provided with an inlet.
Wet classifier described in No. 3. 5. The wet classifier according to claim 1, wherein the spiral impeller and the scraping bucket are separated from each other. 6. The spiral impeller and the raking bucket are rotatably supported respectively, and the spiral impeller and the raking bucket have driving means capable of rotating at different rotational speeds. The wet classifier according to any one.