JP6803612B2 - Pressurized rotary plate type solid-liquid separator - Google Patents

Description

The present invention relates to a solid-liquid separation device that dehydrates sludge water generated in a wastewater treatment process or the like in a sewage treatment plant, a urine treatment plant, or another facility.

Sludge water generated in sewage treatment plants, sewage treatment plants or other industries is dehydrated and reduced in volume by a method represented by the following.

First, sludge water is coagulated in advance to coarsen sludge particles. Next, use a filter press, belt press, screw press, centrifugal dehydrator, vacuum pressure dehydrator, multiple rotary plate type solid-liquid separator, pressurized rotary plate type solid-liquid separator, etc. to remove the water in the sludge water to the outside of the system. A so-called dehydration treatment is performed to increase the solid concentration while discharging.

The multi-rotating plate type solid-liquid separator sandwiches sludge water between the upper circular rotating plate group and the lower circular rotating plate group, and pushes the sludge water to the downstream side by the rotation of both rotating plates. The dehydrated sludge is discharged from the gap between the two, and the dehydrated sludge is discharged from the dehydrated sludge discharge portion provided at the most downstream portion. Further, in the pressure type rotary plate type solid-liquid separator, an elliptical rotary plate is rotatably arranged between a large number of slit bars to form an upstream portion and a downstream portion, and is added above the rotary plate. A pressure plate is arranged, the upstream part is a gravity dehydration part, the downstream part is a pressure dehydration part by pressing the pressure plate, and sludge-containing water is supplied from above the rotary plate of the most upstream part to form a gap between the rotary plates and a gap between the rotary plates. By removing the liquid from the gap between the rotating plate and the slit bar and separating it, the dehydrated sludge placed on the rotating plate is moved to the gravity dehydration section and the pressurized dehydration section, and the dehydrated sludge is moved to the most downstream portion. It is discharged from the provided dehydrated sludge discharge section.

Both the multi-rotating plate type solid-liquid separator and the pressurized rotary plate type solid-liquid separator have the advantages of being easy to operate, eliminating the need to replace the filter cloth, and being easy to maintain. it is possible pressurization by the pressing plate, when changing from minor to the length size further by the rotation of the elliptical rotary plate, the effect of such strong driving force is applied to the downstream side with respect to dewatered sludge, Compared with the multi-rotating plate type solid-liquid separating device, the pressure type rotating plate type solid-liquid separating device can obtain dehydrated sludge with a reduced water content and has a large processing capacity, with respect to the unit processing capacity. The equipment price is low. Therefore, in recent years, the pressure type rotary plate type solid-liquid separator has come to be used more frequently than the multiple rotary plate type solid-liquid separator.

Japanese Unexamined Patent Publication No. 2016-13556

However, the conventional pressurized rotary plate type solid-liquid separator has the following drawbacks.

That is, when the pressure plate existing above the rotating plate is pressed further downward in an attempt to further reduce the water content, the rotating plate bites into the dehydrated sludge placed on the rotating plate of the pressurized dehydration part and runs idle. , Dewatered sludge will not be discharged from the dewatered sludge discharge part. In short, the dehydrated sludge is clogged in the pressurized dehydration section.

Therefore, conventionally, the dehydrated sludge is dehydrated by pressing a pressure plate so that the dehydrated sludge is not clogged by the pressurized dehydrated portion, but it is not possible to obtain the dehydrated sludge having a satisfactory water content.

The present invention solves the above-mentioned drawbacks of the conventional pressurized rotary plate type solid-liquid separator, and can obtain dehydrated sludge with a lower water content without clogging the dehydrated sludge in the pressurized dehydrated portion. An object of the present invention is to provide a rotating plate type solid-liquid separator.

The present inventions only slightly change the structure of the conventionally used pressurized rotary plate type solid-liquid separator, so that the dehydrated sludge is not clogged in the pressurized and dehydrated portion, and the water content is further lowered. We have found that dehydrated sludge can be obtained, and have reached the present invention.

That is, in the pressurized rotary plate type solid-liquid separator according to the present invention, the rotary plate is rotatably arranged between a large number of slit bars to form an upstream portion and a downstream portion, and the rotary plate is added above the rotary plate. A pressure plate is arranged, the upstream part is a gravity dehydration part, the downstream part is a pressure dehydration part by a pressure plate, and sludge-containing water is supplied from above the rotary plate in the most upstream part to form a gap between each rotary plate and the rotary plate. By removing the liquid from the gap generated in the slit bar and separating it, the dehydrated sludge placed on the rotating plate is moved to the gravity dehydration section and the pressure dehydration section, and the dehydration sludge is provided in the most downstream portion. In the pressurized rotary plate type solid-liquid separator that discharges from the sludge discharge part,
It is characterized in that the number of rotating plates arranged in the pressure dehydrating portion is smaller than the number of rotating plates arranged in the gravity dehydrating portion.

In such a pressure type rotary plate type solid-liquid separator according to the present invention, the number of rotary plates arranged in the pressure dehydration section is 30% to 70% of the number of rotary plates arranged in the gravity dehydration section. The range is preferable, and the range is more preferably 45% to 55%. By forming the rotating plate with such a quantity, it is possible to effectively prevent the dewatered sludge from being clogged in the pressurized dewatering portion.

In such a pressurized rotary plate type solid-liquid separator according to the present invention, the rotary plates arranged in the front-rear and left-right sides of the rotary plate in the pressure-dewatering section are eliminated every other one, so that the rotary plates are arranged in the pressure-dewatering section. It is preferable that the number of rotating plates to be subjected to is in the range of 45% to 55% of the rotating plates arranged in the gravity dehydration section from the viewpoint of achieving a uniform and low water content dehydration treatment. Further, it is also preferable that the rotating plate is oval, oval, or rectangular with rounded or cut corners, because it is possible to realize a dehydration treatment that is homogeneous and has a low water content.

The pressure disc type solid-liquid separator of the present invention is arranged in, for example, the gravity dehydration section by reducing the number of rotary plates arranged in the pressure dehydration section with respect to the number of rotary plates arranged in the gravity dehydration section. The number of rotary plates to be arranged in the pressure dehydration section is set in the range of 30% to 70%, preferably the above quantity is in the range of 45% to 50%, most preferably in the pressure dehydration section. By eliminating every other rotating plate placed in front, back, left and right of the rotating plate, the number of rotating plates placed in the pressure dehydration section is in the range of 45% to 50% of the rotating plate placed in the gravity dehydration section. Therefore, it is possible to obtain dehydrated sludge with a lower water content without clogging the pressurized dehydration section with the dehydrated sludge.

It is explanatory drawing which shows an example of the pressure type rotary plate type solid-liquid separation apparatus of this invention. It is an enlarged explanatory view of the main part of the pressure type rotary plate type solid-liquid separator. It is a partial notch explanatory drawing which looked at the rotary plate and the slit bar of the pressure type rotary plate type solid-liquid separator of this invention from above. It is a partial notch explanatory view seen from the upper side of the rotary plate and the slit bar of the conventional pressure type rotary plate type solid-liquid separator. It is explanatory drawing which showed the rotating plate which can be used in this invention.

The present invention will be described in detail below with reference to the drawings.
FIG. 1 is an explanatory view of the pressurized rotary plate type solid-liquid separator 1 of the present invention, and FIG. 2 is a housing of the pressurized rotary plate type solid-liquid separator 1. A sludge-containing water supply pipe 3 is connected to the upper end of the housing 2, and a separation liquid discharge pipe 4 is attached to the lower end of the housing 2.

Rotating shafts 6 fitted with a large number of elliptical rotating plates 5 are vertically supported in the housing 2 from the upstream side to the downstream side, and slit bars 7 are horizontally provided above each rotating shaft 6. There is.

FIG. 2 is an enlarged external view of a main part of the pressurized rotary plate type solid-liquid separator 1, in which rotary plates 5 are arranged between a large number of slit bars 7, and each rotary plate 5 is interposed via a spacer ring 8. It is fitted on the rotating shaft 6.

The thickness of each slit bar 7 and the rotary plate 5 is 1 to 2 mm, and the number of slit bars 7 varies depending on the processing amount, but 100 to 500, and the rotary plate 5 fitted to one rotary shaft 6 are It is about 100 to 500 sheets. Further, an ellipse having a major axis of 100 to 200 mm and a minor axis of 50 to 100 mm is adopted, and 8 to 10 rows of rotating plates 5 are arranged between the slit bars 7 from upstream to downstream. There are many.

The rotation directions of the rotating plates 5 are the same, and the rotating plates 5 located between the same two slit bars 7 and adjacent to each other in the vertical direction are set to rotate without contacting each other.

A pressure plate 9 having three types of inclination angles a, b, and c is installed on the upper part of the housing 2 from the upstream side to the downstream side, and the portion of the inclination angle a is the gravity dehydrating portion A, the inclination angles b, and c. The portion is the pressure dehydration portion B. A pressurizing mechanism 10 is attached to the downstream side of the pressurizing plate 9, and the pressurizing plate 9 is moved up and down by the pressurizing mechanism 10 with the pressurizing plate support shaft 11 as a fulcrum to reach the tip downstream of the slit bar 7. The gap between the downstream pressure plate 9 and the pressure plate 9 can be changed, and the gap serves as the dehydrated sludge discharge section 12.

The dehydrated sludge 13 discharged from the dehydrated sludge discharge unit 12 falls into the dehydrated sludge receiving tank 14. An air cylinder or the like can be used as the pressurizing mechanism 10.

FIG. 3 is a partially cutaway explanatory view of the rotary plate 5 and the slit bar 7 of the pressurized rotary plate type solid-liquid separator 1 as viewed from above, and the rotary plate 5 arranged in the pressure dehydration section B is gravity dehydrated. Compared with that of part A, every other rotating plate that should be arranged in front, back, left and right is eliminated, and the number of rotating plates arranged in pressure dehydrating part B is about 50 compared with that of gravity dehydrating part A. It is%. Note that the dotted line in FIG. 3 indicates the rotation axis 6.

FIG. 4 is a partially cutaway explanatory view of the rotary plate 5 and the slit bar 7 of the conventional pressurized rotary plate type solid-liquid separator as viewed from above, and is a rotation arranged in the gravity dehydration section A and the pressure dehydration section B. The number of plates 5 is exactly the same.

In the pressure type rotary plate type solid-liquid separator of the present invention and the conventional pressure type rotary plate type solid-liquid separator, as shown in FIG. 3, the number of rotary plates 5 arranged in the gravity dehydration section A is added. The major difference is that the number of rotating plates 5 arranged in the pressure dehydration section B is reduced.

[Action]
Next, the operation of the pressurized rotary plate type solid-liquid separator 1 of the present invention will be described.
While rotating each rotating plate 5, sludge water having a water content of 97 to 99%, which has been previously coagulated with the organic polymer coagulant alone or with the organic polymer coagulant and the inorganic coagulant, is supplied to the sludge-containing water supply pipe. 3 is supplied above the most upstream rotary plate 5 of the pressurized rotary plate type solid-liquid separator 1.

The agglomerated solid matter in the sludge water becomes dehydrated sludge 13 and stays at the upper part of the rotating plate 5 or the slit bar 7, and the water falls to the lower part through the gap between the rotating plates 5 or the gap between the rotating plate 5 and the slit bar 7. .. While placing the dehydrated sludge 13 on the upper part of the rotary plate 5 or the upper part of the slit bar 7, the dehydrated sludge 13 is moved from the upstream side to the downstream side of each rotary plate 5 by the rotation of each rotary plate 5, and the dehydrated sludge is sequentially moved during this period. The water in 13 is eliminated. Finally, the dehydrated sludge 13 on the upper part of the rotating plate 5 is discharged into the dehydrated sludge receiving tank 14 as the dehydrated sludge 13 from the dehydrated sludge discharging portion 12 which is a gap between the slit bar 7 and the pressure plate 9 located at the most downstream. To.

The sludge with a water content of 97 to 99% becomes dehydrated sludge with a water content of about 92% in the gravity dehydration section A of the pressurized rotary plate type solid-liquid separator 1, and in the pressure dehydration section B due to the pressing force of the pressure plate 9. When it is further dehydrated and discharged from the dehydrated sludge discharge unit 12, the dehydrated sludge having a water content of 80 to 85% is dehydrated. The water excluded during this period is discharged from the separated water discharge pipe 4.

In the present invention, by eliminating every other rotating plate arranged in front of and behind and to the left and right of the rotating plate 5 in the pressurized dehydration section B, the dehydrated sludge 13 in the pressurized dehydration section B even if the pressure plate 9 is strongly pressed. The dewatered sludge 13 can be satisfactorily discharged from the dewatered sludge discharging unit 12 without the rotating plate 5 biting into the rotating plate 5 and spinning. That is, the dewatered sludge 13 is not clogged with the pressure dewatering section B.

In the conventional pressurized rotary plate type solid-liquid separator shown in FIG. 4, the number of rotary plates arranged in the gravity dehydration section A and the pressure dehydration section B is exactly the same, and thus the present invention described above. When the pressure plate is pressed with the same pressing force as the device, the rotating plate bites into the dehydrated sludge in the pressurized dehydration section B and runs idle, the dehydrated sludge is clogged in the pressurized dehydration section B, and the dehydrated sludge is discharged from the dehydrated sludge discharge section. Cannot be discharged.

Therefore, in the conventional pressure type rotary plate type solid-liquid separator, the rotary plate does not bite into the dehydrated sludge in the pressure dehydration section B, and the pressure plate can be pressed only with a weak pressing force so as not to idle. As a result, only dehydrated sludge having a water content of about 88 to 91% can be obtained.

As the rotary plate 5 that can be used for the rotary plate 5 of the pressure type rotary plate type solid-liquid separator of the present invention shown in FIG. 1, an elliptical shape D, an oval E, and a corner portion are used as shown in FIG. A rounded or cut rectangle F can be mentioned.

Further, the pressure type rotary plate type solid-liquid separator of the present invention is characterized in that the number of rotary plates 5 arranged in the pressure dehydration section B is smaller than the number of rotary plates 5 arranged in the gravity dehydration section A. However, the quantity of the rotary plate 5 arranged in the pressure dehydration section is set in the range of 30% to 70%, preferably in the range of 45% to 55% with respect to the quantity of the rotary plate 5 arranged in the gravity dehydration section A. You should do it.

For example, when it is 29% or less, the quantity of the rotating plate 5 is too small, so that the propulsive force for moving the dewatered sludge downstream becomes weak, and the dewatered sludge tends to be clogged in the pressurized dewatering section B, and the dewatered sludge discharge section There is a tendency that dehydrated sludge cannot be discharged.

Further, when it is 71% or more, since the quantity of the rotating plate 5 is too large, the rotating plate 5 easily bites into the dehydrated sludge, and the dehydrated sludge is easily clogged in the pressurized dehydration section B. Similarly, from the dehydrated sludge discharge section. There is a tendency that dehydrated sludge cannot be discharged.

As shown in FIG. 3, the number of rotating plates 5 arranged in the pressure-dewatering unit B by eliminating every other rotating plate 5 arranged in the front-rear and left-right directions of the rotating plate 5 in the pressure-dewatering unit B. Is most preferably in the range of 45% to 55% of the rotating plate 5 arranged in the gravity dehydration section A.

In the embodiment shown in FIG. 3, every other rotating plate 5 arranged on the front, rear, left and right sides of the entire rotating plate 5 in the pressure dehydration section is eliminated, but the rotating plate 5 is fitted on the most downstream rotating shaft. Even if the rotating plate 5 is bitten into the dehydrated sludge, the dehydrated sludge is only discharged from the dehydrated sludge discharge part as it is, so that it does not have any particular effect on the clogging of the dehydrated sludge, and therefore, this most downstream. The same as the conventional device may be used without excluding only the rotating plate fitted to the rotating shaft located at.

The pressurized rotary plate type solid-liquid separator according to the present invention can be widely used for dehydrating sludge water generated in various wastewater treatment steps.

1 ... Pressurized rotary plate type solid-liquid separator 2 ... Housing 3 ... Sludge-containing water supply pipe 4 ... Separation liquid discharge pipe
5 ... Rotating plate 6 ... Rotating shaft 7 ... Slit bar 8 ... Spacer ring 9 ... Pressurized plate 10 ... Pressurizing mechanism 11 ... Pressurized support shaft 12 ... Dewatered sludge discharge part 13 ... Dewatered sludge 14 ... Dehydrated sludge receiving tank A ... Gravity dehydration part B ... Pressurized dehydration part

Claims (5)

A rotating plate is rotatably arranged between a large number of slit bars to form an upstream part and a downstream part, and a pressure plate is arranged above the rotating plate to add a gravity dehydrating part to the upstream part and a downstream part to the downstream part. It is a pressurized dehydration part by a pressure plate, and it rotates by supplying sludge-containing water from above the rotating plate in the uppermost stream and removing liquid from the gap between each rotating plate and the gap generated between the rotating plate and the slit bar. In a pressurized rotary plate type solid-liquid separator that moves the dehydrated sludge placed on the plate to the gravity dehydration section and the pressure dehydration section and discharges the dehydrated sludge from the dehydrated sludge discharge section provided at the most downstream portion. ,
A pressure type rotary plate type solid-liquid separator characterized in that the number of rotary plates arranged in the pressure dehydration section is smaller than the number of rotary plates arranged in the gravity dehydration section. The pressure type rotary plate type solid liquid according to claim 1, wherein the quantity of the rotary plates arranged in the pressure dehydration section is in the range of 30% to 70% with respect to the quantity of the rotary plates arranged in the gravity dehydration section. Separator. The pressurized rotary plate type solid-liquid according to claim 1 or 2, wherein the number of rotary plates arranged in the pressure dehydration section is in the range of 45% to 55% of the rotary plates arranged in the gravity dehydration section. Separator. By eliminating every other rotating plate placed in front of, behind, left and right of the rotating plate in the pressure dehydrating section, the number of rotating plates placed in the pressure dehydrating section is 45% of the number of rotating plates placed in the gravity dehydrating section. The pressurized rotary plate type solid-liquid separator according to claim 3, wherein the content is in the range of ~ 55%. The pressurized rotary plate type solid-liquid separator according to any one of claims 1 to 4, wherein the rotary plate is oval, oval, or rectangular with rounded or cut corners.

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