JPH0123165B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention introduces a sludge stock solution containing filter dregs particles into a filtration tank equipped with two upper and lower rotating filter bodies. Regarding the improvement of a sludge treatment filtration device that separates and drains the water contained in the sludge stock solution while transferring the top of the sludge and separates it into a filtrate and a sludge cake. This invention relates to a type of filtration device in which fins with a maximum diameter and a minimum diameter are attached to the body to promote the progress of the sludge cake, and the sludge cake gradually rises above the level of the undiluted sludge.

<Prior art> The basic structure of a sludge treatment filtration device that separates water from a sludge stock solution containing filter slag particles and processes it into a filtrate and a sludge cake has already been described in Japanese Patent Publication No. 53-34346,
The contents are disclosed in detail in JP-A-52-62774, JP-A-53-117865, and so on. However, in conventional sludge treatment filtration equipment, after long-term use, the sludge cake solidifies after the filtrate is separated, and the sludge cake cannot easily proceed to the sludge cake discharge port. There is a serious defect in that the undiluted sludge containing it leaks out.
In reality, despite various experimental uses, there was no prospect of practical use because it could not be used continuously over a long period of time.

To explain in detail, conventional filter bodies are constructed by arranging a large number of relatively thick small-diameter fins, intermediate-thick medium-diameter fins, and slightly thin-walled large-diameter fins in sets of three. It consisted of In addition, the medium-diameter fins and large-diameter fins are provided with filtrate water holes at positions equidistant from the center of the fin, and the filtrate water holes of each fin overlap and face toward the axial direction of the filter body. The filter body was arranged so that a water passage pipe was formed, and the filtrate was configured to flow outward in the axial direction of the filter body.

When using a conventional filtration device, first, the sludge cake discharge port is blocked with a rag or the like to prevent the undiluted sludge from flowing out from the sludge cake discharge port, and then the sludge particles are removed. The undiluted sludge solution was introduced into the filtration tank, and the water (filtrate) coming out of the undiluted sludge solution was waited for to be gradually drained out of the filtration tank through the filtrate water holes. The filter body is a cylindrical member with gaps formed by polymerizing a large number of fins, and the filter body array is formed by arranging the filter bodies lying sideways and joining them in parallel in the axial direction. The rows of filter bodies are arranged in two stages, upper and lower, and the large-diameter fins of the filter bodies protrude into the slit grooves of adjacent filter bodies, forming a so-called intersecting row. The raw sludge containing filter particles is dehydrated and gradually accumulates on the filter to form a sludge cake. By rotating the filter body in the direction of the sludge cake discharge port, the sludge cake gradually advances toward the sludge cake discharge port, and at the same time, the residual filtrate remaining in the sludge cake is gradually filtered from the filtrate water passage hole. Drained outside the tank.

As the filtrate is gradually discharged, the fine suspended solids contained in the raw sludge gradually harden and become clogged, and the fine suspended solids also form in the filtrate water holes. A clogging phenomenon occurs. However, even with conventional technology, adjacent large-diameter fins rotate to mechanically crush the solidified fine suspended solids and remove the fine suspended solids that clog the filtrate water holes. The condition has been restored so that the sludge cake can be moved to the discharge port. As a result, although it was normally planned to withstand continuous use,
Conventional mechanical clearing of fine suspended solids by intersecting large-diameter fins with slit grooves is not complete, and if the flow of sludge cake is uneven and flows partially, the sludge may be removed in areas where it does not flow. A phenomenon occurred in which the cake became tightly packed due to long-term dehydration, and a large resistance torque was generated against the rotation of the filter body.
In this case, mechanical clearing using large-diameter fins is not effective, and the sludge cake will no longer move forward based solely on the rotation of the filter, and if you forcefully drive the device, the rotational drive device will be overloaded and may become unable to move. This resulted in damage to the machine.

Additionally, if the dewatering function of the filtration device malfunctions, the sludge cake near the sludge cake outlet is pushed out by the water pressure of the sludge undiluted solution inside, and the sludge undiluted solution containing filtration particles is directly discharged from the sludge cake. There was a situation where the water leaked out from the exit.

Due to these defects, conventional filtering devices cannot be used continuously over a long period of time in reality, although the basic idea is revolutionary.

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel filtration device that eliminates the drawbacks of the prior art and can withstand continuous use. According to the filtration device of the present invention, in addition to the conventional three types of fins constituting the filter body, there are five types of fins: extra-large diameter fins having a larger diameter than conventional large-diameter fins, and extra-small diameter fins having a smaller diameter than small-diameter fins. The large-diameter fins and the small-diameter fins are arranged at appropriate intervals, so even if the sludge cake is dehydrated more than necessary, the large-diameter fins can disassemble the cake and move it. The sludge cake can be returned to a normal state, and the sludge cake can be smoothly transferred to the sludge cake discharge port. In addition, the filter rows, which are configured in two stages (upper and lower), are gradually raised toward the sludge cake discharge port, and the sludge cake discharge port is raised to the same height as the filter closest to the sludge cake discharge port in the lower filter row. By installing it at a higher position, the sludge concentrate will not flow out from the sludge cake outlet, there will be no need to pack it with rags at the start of operation, and there will be fewer failures than before. , it has become possible to realize continuous and reliable use of the device over a long period of time.

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 is a perspective view showing the entire filtering device according to the present invention. The filtration device 10 has a sludge stock solution inlet 12 and a filtrate outlet 1 as in the conventional filtration device.
4 and a sludge cake outlet 16
It has a configuration in which multiple rows of filter bodies 20 are arranged.
The arrangement of the filter body is such that a cylindrical filter body formed by polymerizing a large number of fins is arranged so that its axis is perpendicular to the longitudinal direction of the filter tank 18, and a plurality of filter bodies are arranged parallel to the bottom surface of the tank. The filter bodies are arranged in parallel and so that the fins of adjacent filter bodies intersect.

FIG. 2 is a plan view showing the intersecting state of the filter body 20 constituting the filter device according to the present invention and the fins constituting the filter body. The filter body 20 has a structure in which a large number of thin disk fins having different diameters are stacked on a shaft 21, and the filter body 20 has a cylindrical shape as a whole. The fins constituting the filter body 20 are composed of relatively thick small-diameter fins 22, intermediate-thick medium-diameter fins 23, and slightly thin-walled large-diameter fins 24. Furthermore, in this invention, the fins have a smaller diameter than the small-diameter fins. A small diameter fin 26 and a maximum diameter fin 27 having a larger diameter than the large diameter fin 24 are attached at appropriate locations. Small diameter fin 22, medium diameter fin 23, and large diameter fin 24
The intersecting arrangement of the filters is the same as the intersecting rows of conventional filter bodies. In this invention, maximum diameter fins 27 are installed at appropriate intervals in place of the conventional large diameter fins 24. The fins of the adjacent cylindrical filter into which the maximum diameter fins 27 protrude are arranged so that the tip of the maximum diameter fins 27 protrudes deeper into the slit groove than before.
Very small diameter fins having a smaller diameter than the conventional small diameter fins 22 are disposed to face each other. This prevents the tip of the maximum diameter fin from coming into contact with the minimum diameter fin. The driving force for moving the sludge cake is proportional to the contact surface area between the sludge cake and the surface of the filter body, so by installing extra-large diameter fins, the contact area increases and the driving force for rotational transfer increases. Filtrate water passage holes 30 are provided in the maximum diameter fin, the large diameter fin, and the medium diameter fin at positions equidistant from the center of the fin. Similar to the conventional embodiment, the filtrate passage holes 30 formed in each fin overlap to form a filtrate passage pipe. A filtrate water pipe formed by overlapping each fin is provided in the axial direction of the filter body, and the filtrate is passed through the filter body 20.
The filtrate flows out to both sides of the filtrate, passes through the sides of the filtration tank, and is discharged to the outside from the filtrate outlet 14.

FIG. 3A is a cross-sectional view showing the degree of intersection of a conventional filtration device, and FIG. 3B is a cross-sectional view of a filtration device according to the present invention. The degree of protrusion of the filter column in the filter apparatus according to the present invention shown in FIG. 3B is configured to be larger than the degree of protrusion of the filter column in the conventional filter column shown in FIG. 3A. The wave-shaped sludge cake path 42 (shaded area) sandwiched between the upper and lower filter rows has a constant shape depending on the arrangement of the filter rows. In order for the dewatered sludge cake 40 to be transferred to the sludge cake outlet 16, the sludge cake itself must be deformed along the wave-shaped "neck" of the filter body. A fluid sludge cake is easily deformed, but a sludge cake that is solidifying due to advanced dewatering becomes difficult to deform, and requires a driving force toward the sludge cake discharge port 16. Therefore,
As shown in FIG. 3B, one factor that facilitates movement is to reduce the difference in height between the "constrictions" of the waveform. Therefore, in the filtration device according to the present invention, the moving/propulsive force of the sludge cake 40 is further enhanced by increasing the plunge ratio of adjacent filter rows. However, since the intersecting fins of the filter body rotate in opposite directions,
When the mating ratio is increased, the resistance torque increases due to the friction caused by the fine suspended solids that have accumulated in the gaps between the fins. Therefore, it is not possible to make all the fins intersect more deeply than before. In the filtration device according to the present invention, since the maximum diameter fins and the minimum diameter fins are installed at appropriate intervals, there are parts where the propulsive force is high, but the resistance torque is not so large that it becomes a problem.

FIG. 4 is a cross-sectional view of the filtration device according to the present invention. The filter body 20 has extremely small diameter fins 26 and maximum diameter fins 27 arranged at appropriate locations on the filter body. If the difference between the large diameter fin and the maximum diameter fin is m, then the distance n between the maximum diameter fin and the maximum diameter fin is
It is desirable that the relationship n=2m. Thereby, the contact area between the sludge cake 40 and the filter body 20 increases approximately twice. On the other hand, the increase in resistance torque does not actually pose a problem since the maximum diameter fins are installed sparsely.

In order to move the sludge cake 40 to the sludge cake discharge port 16, it is important to constantly deform the shape of the sludge cake without fixing it, but with the configuration of this invention, the propulsive force increases on average. Therefore, the uneven movement of the sludge cake 40 is eliminated, so that the clogging phenomenon that occurs in the conventional system can be avoided, and continuous practical use over a long period of time becomes possible.

FIG. 5 is a side view showing another embodiment of the filtration device according to the present invention. Sludge cake outlet 16
, the filter rows configured in two stages (upper and lower) are gradually raised toward the sludge cake discharge port, and the sludge cake discharge port 16 is at the same height as the filter closest to the sludge cake discharge port in the lower filter row. It is installed upside down or at a higher position. This eliminates the need to stuff the sludge cake discharge port 16 with waste cloth at the start of operation, which not only saves time but also increases the commercial value of the device. In addition, the phenomenon in which the sludge cake is pushed out from the sludge cake discharge port 16 by the pressure of the sludge stock solution inside and the sludge stock solution protrudes is caused by the fact that the sludge cake discharge port 16 is the closest to the sludge cake discharge port in the lower filter row. Since it is installed at the same height as or higher than the filter body, the undiluted sludge will not protrude even if the pressure increases.

<Effects of the Invention> As detailed above, the filtration device according to the present invention is configured to disassemble the sludge cake and promote its movement using the maximum diameter fins arranged at appropriate intervals. It does not stop and become clogged, and since extra-large diameter fins are installed at appropriate positions, the undiluted sludge solution is not dehydrated unevenly, making it possible to smoothly transfer the entire sludge cake to the sludge cake outlet. be. In addition, the filter row is gradually raised toward the sludge cake discharge port, and the sludge cake discharge port 16 is raised to the same height as the filter body closest to the sludge cake discharge port in the lower filter row, or higher than that. By installing it in a high position, there is no need to pack it with waste cloth at the start of operation, which is hassle-free and clean. Furthermore, even if the sludge cake is pushed out by internal pressure, the sludge containing fine suspended solids can be removed. It is possible to avoid a situation in which the raw solution flows out from the sludge cake outlet. This dramatically reduces failures compared to conventional equipment, enables stable operation over long periods of time, and makes it durable for continuous use, allowing groundbreaking inventions to be put into practical use for the first time. I ended up having to do it.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the entire filtering device according to the present invention, FIG. 2 is a plan view showing the intersecting state of the filter body 20 and the fins constituting the filter body, and FIG. 3A is a conventional 3B is a cross-sectional view of the filtration device according to the present invention; FIG. 4 is a cross-sectional view of the filtration device; FIG. 5 is a cross-sectional view of the filtration device; FIG. It is a side view showing an example of this. 10: Filtration device, 12: Sludge stock solution injection port, 1
4: Filtrate outlet, 16: Sludge cake outlet, 1
8: filter tank, 20: filter body, 21: shaft, 22: small diameter fin, 23: medium diameter fin, 24: large diameter fin,
26: Extremely small diameter fin, 27: Extremely large diameter fin, 3
0: filtrate water hole, 40: sludge cake, 42: sludge cake path, 50: sludge raw liquid level, m: difference between large diameter fin and maximum diameter fin, n: interval between maximum diameter fin and maximum diameter fin.

Claims (1)

[Scope of Claims] 1. A cylindrical filter body constructed by stacking a large number of combinations of small-diameter fins, medium-diameter fins, and large-diameter fins made of thin disks with different diameters in a filtration tank,
A plurality of filter bodies are arranged in parallel in the axial direction to form a filter row,
The row of filter bodies is configured in two stages, upper and lower, and the fins of the fins constituting the filter bodies are arranged so that the large diameter fins enter the narrow grooves between the fins of the adjacent filter bodies, and Water holes are provided in the axial direction of the filter body,
In addition, in a filtration device that transfers the sludge stock solution introduced into the filter tank to the sludge cake discharge port by rotation of the filter body, and discharges water contained in the sludge stock solution to the outside of the device from the filtrate discharge port, the filter body In addition to adding and combining an extremely small diameter fin consisting of a thin circular plate with a diameter smaller than that of the small diameter fin, and an extremely large diameter fin consisting of a thin circular plate having a larger diameter than the large diameter fin,
A filtration device characterized in that the maximum diameter fins are opposed to and protrude into the minimum diameter fins of an adjacent filter body. 2 In the filtration device described in item 1 above, the upper and lower 2
The filter rows configured in stages are arranged to gradually rise toward the sludge cake discharge port, and the sludge cake discharge port is placed at the same height as the filter closest to the sludge cake discharge port in the lower filter row. A filtration device characterized by being installed upside down or at a higher position.