JPH0231806A - Rotary filtration apparatus having squeezing pressure adjusting function - Google Patents

Abstract

PURPOSE:To prevent a filter member form damage due to exertion of excessive squeezing pressure for cake between a group of the filter elements to the filter elements by arranging plural filter element groups to the inside of a filter chamber in a line and in a same direction, and forming discontinuous reduced pressure parts among each filter element group. CONSTITUTION:When feed liquid is forced from a feeding port 12 and filter elements 2 are rotated, suspended fine particles are heaped between external periphery of small filter element pieces 22 and large filter element pieces 21, 21, and filtrate is discharged simultaneously through filtrate holes 23 from a filtrate chamber 11 and a liquid discharge port 14. A discharge rate of the cake is adjusted by the speed of rotation of the filter elements 2. When the space between the rows (a), (a) of the filter elements is filled with a considerably large amt. of the cake, a squeezing pressure for the cake exerts on the filter elements 2 when the discharge rate from a discharge port 13 is unbalanced with the speed of rotation of the filter elements. But, when the cake accumulates between upper and lower confronting filter elements A, A near the discharge port 13 and a space to the reduced pressure part 3 is filled with the cake, succeeding cake escapes to a rear side of the filter elements 2 from the reduced pressure part 3.

Description

[Detailed Description of the Invention] This invention uses a rotating filter body! ! ! It is related to filtration equipment that filters turbid liquid.

Conventionally, as a filtration device for filtering a suspension using a rotating filter body, there are Japanese Patent Publication No. 47-46416 and Japanese Patent Publication No. 57-4560.
No. 6 has been disclosed, but these filtration devices have two rows of filter bodies arranged at appropriate intervals in a filtration tank, and the filter rows in each row are not all assembled continuously. It was something that had been done. These devices perform their filtration through a layer (or cake) of suspended particulates, and as the water content decreases, the cake between the rows of filter bodies hardens. When this hardening progresses more than necessary, if filtration is continued, the cake hardening will act as a squeezing pressure on the filter body, causing damage to the filter body and making filtration impossible.

This invention enables the device itself to automatically adjust the squeezing pressure applied to the filter body in order to filter suspensions with different properties (for example, the size and amount of suspended particles) using the same device. This is a device that achieves this, and will be described in detail below with reference to embodiment figures.

The device of this invention includes a filter tank (1) and a plurality of filter bodies (2).
The filter tank (1) is at the top! ! The suspension liquid supply port (12) is connected to the cake discharge port (12) at the front (right side in Figure 1).
A liquid chamber (11) provided with a filtrate drain port (14) is installed on both sides of the filtration chamber (10) provided with a partition wall (1).
5) Separated by (15).

The filter body (2) has large filter pieces (21) and small filter pieces (22) fitted alternately around the rotating shaft (20).
21) and the small filter piece (22) have a thickness difference of 0.1a+m to 2
The large filter piece (21) has a larger diameter than the small filter piece (22), and both have filtrate holes (
23) is perforated.

The filter tank (1) and the filter body (2) consist of a rotating shaft (20) arranged horizontally in the filter chamber (10), and large filter pieces (21) on both sides of the filter body (2) and the partition wall. It is in contact with (15) in a watertight manner. Further, both ends of the filtrate hole (23) are connected to the filtrate chamber (11). A gear (G) connected to a driving device such as a motor (not shown) is fixed to one end of a rotating shaft (20) protruding from the filter tank (1).

The filter bodies (2) are combined by arranging a plurality of filter bodies in one row to form a filter body row (a), and by arranging them in two rows above and below at appropriate intervals to form a filter body group (A). In addition, one row of filter bodies (2) is connected to the large filter piece (21) of the adjacent filter body (2) as shown in Fig. 3.
) to the small filter piece (22) (the large filter piece (21) holding the small filter piece (22)) (the small filter piece (22) facing the (21)
is inserted).

In the filtration chamber (10), two sets of filter bodies (A) (A) are arranged in a - row in the same direction (left and right direction in Fig. 1), and each filter body group (A) ( An unconnected pressure reducing section (3) is provided between A). Further, each filter body group (A) (A) is driven to rotate separately, so that the rotation speeds of the filter bodies (2) can be set to be the same or different. Code in the figure (16)
indicates the lid of the discharge port (13).

As shown in FIG. 5, the filter body row (a) is connected to the discharge port (13
) near the discharge port (13).
) may be placed above the water surface, and in that case, the cover (16) of the discharge port (13) is not necessary.

In addition, the bottom of the filtration chamber (10) may be made to have a sloped structure, or an injection nozzle (N) may be provided at the bottom of the filtration chamber (10) facing backward (leftward in Fig. 4), and the pressure may be emitted from the nozzle. Precipitate by spraying water (or compressed air)! ! The turbidity particles may be introduced into the supply port (12) for the stock solution, or may be stirred.

Alternatively, a suction pump (P) may be attached to the bottom of the filtration chamber (10) to slowly or intermittently (at regular intervals) suck out the precipitated particles and return them to the liquid supply port (12). good.

Next, to describe the function of the device of the present invention, the cake discharge port (13
) with the lid (16) closed, press the stock solution to be filtered through the supply port (12), and rotate each filter body (2) in the direction of the arrow shown in the figure. The suspended fine particles are guided between the large filter pieces (21) (21) of the filter body (2), and the suspended particles are piled up between the large filter pieces (21) (21) around the outer periphery of the small filter pieces (22) and filtered at the same time. The liquid is discharged to the outside of the apparatus from the filtrate chamber (11) and the drain port (14) through the filtrate hole (23) of the filter body (2).

On the other hand, the fine particles stacked on the outer periphery of the filter body (2) fill the vicinity of the cake discharge port (13) as a cake.
) when the stock solution no longer flows out directly from the lid (16).
By the rotation of the mud body (2) which releases the liquid, the liquid is sequentially discharged from the discharge port (13).

(In the case of Fig. 5, since the cake is lifted by the filter body (2), the cake fills near the discharge port (13) due to gravity and is completely discharged.) In addition, the cake discharge speed is the same as that of the filter body (2).
However, if the cake between the rows of filter bodies (aha) becomes considerably full, the speed at which the cake exits from the discharge port (13) and the rotation speed of the filter body (2) become unbalanced. A large amount of water tries to come out from the discharge port (13), and the filter body (2)
(If the rotational speed of the cake is not sufficient to discharge all of the cake), the squeezing pressure of the cake is applied to the filter body (2), but between the vertically opposing filter bodies (A) near the discharge port (13), ! 1
171JL, when the pressure reducing part (3) is full, the following cake escapes from the pressure reducing part (3) to the back of the filter body (2) (vertical direction in Figure 1), and the filled cake disappears from the filter body. (
2) will reduce the pressure applied.

As stated above, this inventive device is! ! In addition to continuously filtering the turbid liquid, it is possible to reduce the pressure when the squeezing pressure of the cake between the filter bodies is excessively applied to the filter bodies, that is, it can be done without doing it manually. Therefore, it has the effect of preventing accidents such as damage to the filter body.

[Brief explanation of the drawing]

The drawing shows an embodiment of the device according to the invention.

Claims (2)

[Claims] (1) Suspension liquid supply port (12) and cake discharge port (13)
) and a filtrate drain port (14) between the liquid supply port (12) and the discharge port (13) in the filtration tank (1). The small filter pieces (22) are fitted alternately around the rotating shaft (20), and the large filter piece (21) or both filter pieces (21) and (22) are provided with filtrate holes (23) in the axial direction. A plurality of filter bodies (2) are provided, and the large filter pieces (21) are arranged in succession corresponding to the outer periphery of the small filter pieces (22) of the adjacent filter bodies (2) to form a filter body row (a). None, a filter body group (A) consisting of a plurality of filter body rows (a) arranged in parallel at predetermined intervals is provided, and the filter body (2) is connected to the drain port (14) of the filtration tank (1). Liquid hole (2
3) in a filtration device that communicates with the filtration tank (1);
A rotary filtration device having a throttle pressure adjustment function, characterized in that a plurality of filter body groups (A) are arranged in a row inside the rotary filtration device. (2) In the filtration device according to item 1, the filtration tank (1) is a rotary filtration device having a throttle pressure adjustment function, in which two groups of filter bodies (A) are internally installed.