JPH10219579A - Screening apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screening apparatus, which further beats undissolved pieces in a papermaking stock to increase yield. SOLUTION: This screening apparatus comprises a tank 4 which stores a papermaking stock; virtually cylindrical screen 3 which is provided in the tank 4 to divide it into a primary chamber 41 and secondary chamber 42; agitating member 2 provided on the outside of the screen 3 to agitate the papermaking stock; papermaking stock inlet 44 and foreign matter outlet 45 provided in the tank 4 in such a way as to face on the primary chamber 41; papermaking stock outlet 46 provided also in the tank 4 in such a way as to face on the secondary chamber 42; and water supply tube 5 which supplies water to the tanks 4 to stop flow of the papermaking stock downstream of the primary chamber 41 but upstream of the foreign matter outlet 45. Flow of the papermaking stock is stopped by water supplied by the water supply tube 5 downstream of the primary chamber 41 but upstream of the foreign matter outlet 45, to increase residence time of the papermaking stock in the tank 4 and thereby to further beat undissolved pieces in the papermaking stock.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a screen for removing foreign substances such as stones, sand, metal fragments and resins from papermaking raw materials such as pulp and waste paper.
More particularly, the present invention relates to a screen device capable of further disintegrating undissolved pieces of papermaking raw material to improve the yield (reduce the reject rate).

[0002]

2. Description of the Related Art Conventionally, there is a screen device of a type in which a stirring member is stirred outside a screen and a papermaking material flows from the outside to the inside of the screen (for example, Koki Shoji).
See FIG. 1 of JP-A-54-30403).

In this screen device, a screen having a substantially cylindrical shape is provided with a support cylinder (center) having a built-in shaft.
The shaft is supported by a support and the tip of the shaft is provided through a bearing through the tip of the support cylinder. A stirring member (Agitator) for stirring the papermaking raw material outside the screen.
Is attached to the tip of the shaft.

[0004] While the papermaking raw material outside the screen is agitated by an agitator (agitator), the selected papermaking raw material is transferred to a secondary chamber through a substantially cylindrical screen.
The unselected papermaking raw material is guided to the downstream side of the papermaking raw material in the primary chamber, and is discharged to the outside through the foreign matter outlet.

[0005]

However, many undissolved pieces remain in the papermaking raw material discharged to the outside via the foreign matter outlet, and if this is discharged as it is, the waste is reduced. There was a problem that the rate increased and the yield was poor.

An object of the present invention is to provide a screen device which solves the above problems.

[0007]

In order to achieve the above-mentioned object, a screen apparatus of the present invention is provided with a tank for storing papermaking raw materials and a primary chamber and a secondary chamber provided in the tank. And
A substantially cylindrical screen having a closed part with one end closed, an open part with the other end opened, and a plurality of side openings, and a stirring member positioned outside the screen to stir the papermaking raw material A papermaking raw material inlet and a foreign material outlet are provided in the tank so as to face the primary chamber, and a papermaking raw material outlet is provided so as to face the secondary chamber, and the downstream side of the papermaking raw material in the primary chamber, A water supply pipe for supplying water into the tank so as to prevent the flow of the papermaking raw material before reaching the foreign matter outlet, and the papermaking raw material that has flowed into the primary chamber from the papermaking raw material inlet through the screw. The papermaking raw material is stirred by the stirring member located outside the screen, the papermaking raw material is caused to flow in from the outside of the screen to the inside, and the carefully selected papermaking raw material is guided to the papermaking raw material outlet. By the supply of water, the primary A downstream side of the papermaking material,
The flow of the papermaking raw material before reaching the foreign matter outlet is prevented, the storage time of the papermaking raw material in the tank is lengthened, and the undissolved pieces of the papermaking raw material are disintegrated.

[0008] A screen device according to a second aspect of the present invention comprises:
2. The screen apparatus according to claim 1, further comprising a connection passage connecting the upstream side and the downstream side of the papermaking raw material in the primary chamber, and a pump provided in the connection passage. The downstream connection passage opening facing the tank is located on the upstream side of the papermaking raw material in the primary chamber from the water supply pipe opening facing the tank of the water supply pipe, and the pump feeds the papermaking raw material downstream on the upstream side. And the undissolved pieces of the papermaking raw material are disintegrated.

[0009] A screen device according to a third aspect of the present invention comprises:
A tank for storing papermaking raw materials, a flat screen provided in the tank and partitioned into a first chamber and a second chamber, and a first chamber located outside the screen. An impeller provided to agitate the papermaking raw material, a substantially cylindrical screen provided in the second chamber, divided into a primary chamber and a secondary chamber, and having a plurality of openings on a side surface; A stirring member positioned outside the substantially cylindrical screen to stir the papermaking raw material; and a foreign material outlet connected to the primary chamber such that a papermaking raw material inlet and a first foreign material outlet face the first chamber. The papermaking raw material outlet is provided in each of the tanks so as to face the secondary chamber, and the flow of the papermaking raw material before reaching the foreign matter outlet on the downstream side of the papermaking raw material in the primary chamber. A water supply pipe for supplying water into the tank so as to prevent The papermaking raw material flowing into the primary chamber from the material inlet through the first chamber and the flat screen is stirred by the stirring member located outside the substantially cylindrical screen, and the papermaking is performed. The raw material is caused to flow from the outside to the inside of the substantially cylindrical screen and the carefully selected papermaking raw material is guided to the papermaking raw material outlet, and the papermaking in the primary chamber is supplied by supplying water from the water supply pipe. On the downstream side of the raw material, the flow of the paper raw material before reaching the foreign matter outlet is prevented, the storage time of the paper raw material in the tank is lengthened, and the undissolved pieces of the paper raw material are disintegrated. It is.

[0010] Further, the screen device according to claim 4 is characterized in that:
4. The screen apparatus according to claim 3, wherein a connection passage connecting the first chamber to the downstream side of the papermaking raw material in the primary chamber, and a connection port of the connection passage to the first chamber are substantially equivalent to an impeller. A downstream connection passage opening facing the center downstream of the connection passage is provided on the upstream side of the papermaking raw material in the primary chamber from a water supply pipe opening facing the tank of a water supply pipe. And the downstream side of the papermaking raw material is connected to the first
And the undissolved pieces of the papermaking raw material are disintegrated.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A screen device according to one embodiment of the present invention will be described with reference to the drawings.

1 to 4, reference numeral 1 denotes a screen device. The screen device 1 stirs a stirring member 2 outside the screen 3 to screen pulp, waste paper and other papermaking raw materials. This is a type of screen that flows from the outside to the inside of the screen 3 and is carefully selected.

The screen device 1 is provided with a tank 4 for storing papermaking raw materials, and is provided in the tank 4 and is divided into a primary chamber 41 and a secondary chamber 42. A substantially cylindrical screen 3 having an open portion 32 having a plurality of openings 33 and a side surface having a plurality of openings 33, and a stirring member 2 positioned outside the substantially cylindrical screen 3 for stirring the papermaking raw material. From the schematic.

The tank 4 has a papermaking raw material inlet 44 and a foreign matter outlet 45.
The papermaking raw material outlet 46 is provided so as to face the primary chamber 41, and the papermaking material outlet 46 is provided so as to face the secondary chamber 42. In the center of the tank 4, a support cylinder 6 for supporting the substantially cylindrical screen 3 is provided.
However, a shaft 7 is provided in the support cylinder 6 via a bearing Z. In addition, at one end of the shaft 7,
The stirring member 2 is attached, and a motor (not shown) and a pulley 8 which engages with a belt (not shown) for transmitting rotation from the motor are attached to the other end of the shaft 7.

A plurality of water supply pipes 5 for supplying water into the tank 4 on the downstream side of the papermaking raw material in the primary chamber 41 and for preventing the flow of the papermaking raw material before reaching the foreign matter outlet 45 are provided. Pieces,
For example, in the present embodiment, four are provided. The distal end side of the water supply pipe 5 is fixed by a ring-shaped member R.

That is, the papermaking raw material of the present embodiment flows downward from the top of the tank 4, and the water in the water supply pipe 5 flows in the direction transverse to the tank 4, so that the flow of the papermaking raw material is prevented. It has become.

Further, the stirring member 2 described above includes a shaft 7
Stirring base 21 (eg, disk) located in a direction perpendicular to
And a plurality (for example, four) of longitudinal members 22 located in the axial direction of the shaft 7 from the tip of the stirring base 21 toward the opening 32 of the screen 3.

The upstream side and the downstream side of the papermaking raw material in the primary chamber 41 are connected by a connection passage 9.
A pump 10 is provided. The downstream connection passage opening 9 a facing the tank 4 on the downstream side of the connection passage 9 is located on the upstream side of the papermaking raw material in the primary chamber 41 from the water supply pipe opening 5 a facing the tank 4 of the water supply pipe 5. . Preferably, the pump 10
It is preferable to provide a fixing member 10b in the connection passage 9 facing the rotary blade 10a so as to have a disintegration function for disintegrating undissolved pieces of papermaking raw material passing through the connection passage 9.

Accordingly, the papermaking raw material flowing into the primary chamber 41 from the papermaking raw material inlet 44 is agitated by the stirring member 2 located outside the screen 3, and the papermaking raw material goes from the outside of the screen 3 to the inside. Then, the selected papermaking raw material is guided to a papermaking raw material outlet 46.

The supply of water from the water supply pipe 5 causes the foreign matter outlet 45 on the downstream side of the papermaking raw material in the primary chamber 41.
The flow of papermaking raw materials before reaching
The storage time of the papermaking raw material in the tank 4 becomes longer, and undissolved pieces of the papermaking raw material are disintegrated. As a result, the reject rate is reduced, and the yield can be improved.

A connection passage 9 for connecting the upstream side and the downstream side of the papermaking raw material in the primary chamber 41 is provided with a pump in the connection passage 9.
By providing 10 respectively, the papermaking raw material on the downstream side is forcibly returned to the upstream side through the connection passage 9 and the undissolved pieces of the papermaking raw material are further disaggregated, thereby improving the yield (rejection rate). Can be reduced).

In the present invention, as shown in the above-described embodiment, the present invention is not limited to a single screen, and can be similarly applied to a so-called composite screen having a plurality of screens. .

That is, the screen device 1 is shown in FIGS.
As shown in FIG. 1, a tank 4 for storing papermaking raw materials, a flat screen S provided in the tank 4 and partitioned into a first chamber A and a second chamber B, and the screen S An impeller I provided in a first chamber A located outside the container and agitating the papermaking raw material and a second chamber B provided with a primary chamber 41 and a secondary chamber 42, one end of which is closed. A substantially cylindrical screen 3 having a closed portion 31 having an open end, an open portion 32 having the other end opened, and a plurality of openings 33 on a side surface, and a papermaking raw material located outside the substantially cylindrical screen 3. And a stirring member 2 for stirring.

In the tank 4, the papermaking material outlet 46 and the first chamber foreign matter outlet D face the first chamber A, and the foreign matter outlet 45 faces the primary chamber 41. Each is provided in the tank 4 so as to face the chamber 42.

The first room foreign matter outlet D is connected to a cleaner C, and the papermaking raw material from which heavy foreign matter has been removed by the cleaner C is:
Through the return passage M, it is again guided to the first chamber A.

At the center of the tank 4, a support cylinder 6 for supporting the substantially cylindrical screen 3 is provided, and within the support cylinder 6, a shaft 7 is provided via a bearing Z. An impeller I is attached to one end of the shaft 7, and a motor (not shown)
Puller that engages with a belt (not shown) that transmits rotation from the motor
Ri 8 is attached. On the side near one end of the shaft 7, the stirring member 2 is attached. The opening of the flat screen S is, for example, a round hole, and the opening 33 of the substantially cylindrical screen 3 is, for example, a slit.

A plurality of water supply pipes 5 for supplying water into the tank 4 on the downstream side of the papermaking raw material in the primary chamber 41 and for preventing the flow of the papermaking raw material before reaching the foreign matter outlet 45 are provided. In this embodiment, for example, four are provided. The distal end side of the water supply pipe 5 is fixed by a ring-shaped member R.

That is, the papermaking raw material of the present embodiment flows from the top to the bottom of the tank 4, and the water in the water supply pipe 5 flows in the direction transverse to the tank 4, so that the flow of the papermaking raw material is prevented. It has become.

Further, the stirring member 2 described above includes a shaft 7
Stirring base 21 (eg, disk) located in a direction perpendicular to
And a plurality (for example, four) of longitudinal members 22 located in the axial direction of the shaft 7 from the tip of the stirring base 21 toward the opening 32 of the screen 3.

The first chamber A and the downstream side of the papermaking raw material in the primary chamber 41 are connected by a connection passage 9, and an on-off valve K for opening and closing the connection passage 9 is provided in the connection passage 9. ing.
The opening / closing valve K is controlled to be opened / closed as required, such as the type of papermaking raw material and the quality of the papermaking raw material. The connection port A1 of the connection passage 9 to the first chamber A, that is, the connection port A1 of the connection passage 9 facing the first chamber A is shown in FIG.
The connection may be at the solid line position as described, but more desirably, as shown by the two-dot chain line, the connection is provided so as to face the approximate center of the impeller I, and in some cases, the connection facing the first chamber A of the connection passage 9. One end of the connection passage 9 is connected to the return passage M instead of the port A1. At this time, it is preferable to make connection so as to use an ejector effect for towing the papermaking raw material in the connection passage 9. And the other end of the connection passage 9, that is, the downstream tank 4
The downstream side connection passage opening 9a facing the water supply pipe 5 is located on the upstream side of the papermaking raw material in the primary chamber 41 from the water supply pipe opening 5a facing the tank 4 of the water supply pipe 5.

Accordingly, the papermaking raw material that has flowed into the primary chamber 41 from the papermaking raw material inlet 44 through the first chamber A and the flat screen S is agitated outside the substantially cylindrical screen 3. The papermaking raw material is stirred by the member 2 and flows from the outside to the inside of the substantially cylindrical screen 3, and the selected papermaking raw material is guided to the papermaking raw material outlet 46.

The supply of water from the water supply pipe 5 causes the foreign substance outlet 45 on the downstream side of the papermaking raw material in the primary chamber 41.
The flow of papermaking raw materials before reaching
The storage time of the papermaking raw material in the tank 4 becomes longer, and undissolved pieces of the papermaking raw material are disintegrated. As a result, the reject rate is reduced, and the yield can be improved.

The first chamber A and the downstream side of the papermaking raw material in the primary chamber 41 are connected by a connection passage 9, and the downstream side of the papermaking raw material is forced into the first chamber A via the connection passage 9. And the undissolved pieces of the papermaking raw material are further disintegrated to improve the yield (reduction of the reject rate).

In particular, the connection port A1 of the connection passage 9 to the first chamber A is connected to the impeller I as shown by a two-dot chain line in FIG.
The pump 10 described in the above-mentioned embodiment becomes unnecessary if the pump 10 is provided so as to face the approximate center of the above. In order to forcibly secure a certain amount of the papermaking raw material on the downstream side to the first chamber A via the connection passage 9, the pump 10 described in the above-mentioned embodiment is optionally provided in the connection passage 9. May be.

[0035]

According to the first aspect of the present invention, the flow of the papermaking raw material downstream of the papermaking raw material in the primary chamber and before reaching the foreign matter outlet by the supply of water from the water supply pipe. To increase the storage time of the papermaking raw material in the tank and to disintegrate the undissolved pieces of the papermaking raw material, so that the undissolved pieces of the papermaking raw material are further disintegrated to improve the yield (reduction of the rejection rate) )be able to.

According to the second aspect of the present invention, in addition to the effects of the first aspect of the present invention, a connecting passage connecting the upstream side and the downstream side of the papermaking raw material in the primary chamber is provided. By providing a pump in the connection passage, respectively, the papermaking raw material on the downstream side is forcibly returned to the upstream side through the connection passage, and the undissolved pieces of the papermaking raw material are further disintegrated,
The yield can be made better (reduction rate can be reduced).

According to a third aspect of the present invention, water is supplied from the water supply pipe to the downstream side of the papermaking raw material in the primary chamber and the papermaking raw material before reaching the foreign matter outlet. In order to prevent the flow and increase the storage time of the papermaking raw material in the tank and to disintegrate the undissolved pieces of the papermaking raw material, the undissolved pieces of the papermaking raw material are further disintegrated to improve the yield (reject Rate can be reduced).

Further, according to the screen device of the fourth aspect, in addition to the effects of the invention of the third aspect described above, a first aspect is provided.
A connection passage connecting the first chamber to the downstream side of the papermaking raw material in the primary chamber, a connection passage connecting the upstream side and the downstream side of the papermaking raw material in the primary chamber, and a connection port of the connection passage to the first chamber. Is provided so as to face the approximate center of the impeller, and a downstream connection passage opening facing the tank downstream of the connection passage is provided at the papermaking of the primary chamber from a water supply pipe opening facing the tank of a water supply pipe. Because it is located on the upstream side of the raw material, the pressure difference is used without using a pump or the like, and the downstream papermaking raw material is returned to the first chamber through the connection passage, and the undissolved pieces of the papermaking raw material are further disintegrated. As a result, the yield can be improved (reduction rate can be reduced).

[Brief description of the drawings]

FIG. 1 is a schematic front partial sectional view of a screen device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view taken along line XX of FIG.

FIG. 3 is a schematic enlarged sectional view showing a part of FIG. 2 in an enlarged manner.

FIG. 4 is a schematic enlarged sectional view showing a part of the connection passage of FIG. 1 in an enlarged manner.

FIG. 5 is a schematic front partial sectional view of a screen device according to another embodiment of the present invention.

FIG. 6 is a schematic sectional view taken along line YY of FIG. 5;

FIG. 7 is a schematic enlarged sectional view showing a part of the connection passage of FIG. 6 in an enlarged manner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Screen device 2 Stirring member 3 Screen 4 Tank 5 Water supply pipe

Claims (4)

[Claims] 1. A tank for storing a raw material for papermaking, a tank provided in the tank, divided into a primary chamber and a secondary chamber, a closed section having one end closed, an open section opened at the other end, and a plurality of side faces. A substantially cylindrical screen having an opening, a stirring member positioned outside the screen for stirring the papermaking raw material, and a papermaking raw material inlet and a foreign matter outlet facing the primary chamber.
A papermaking raw material outlet is provided in each of the tanks so as to face the secondary chamber, so that the flow of the papermaking raw material before reaching the foreign matter outlet is located downstream of the papermaking raw material in the primary chamber. A water supply pipe for supplying water into the tank, wherein the papermaking raw material flowing into the primary chamber from the papermaking raw material inlet is agitated by the agitating member located outside the screen, and the papermaking raw material is provided. Is introduced from the outside to the inside of the screen, and the selected papermaking raw material is guided to a papermaking raw material outlet. By the supply of water from the water supply pipe, the primary chamber is downstream of the papermaking raw material. And stopping the flow of the papermaking raw material before reaching the foreign matter outlet, extending the storage time of the papermaking raw material in the tank, and disintegrating undissolved pieces of the papermaking raw material. -Device. 2. A connection passage connecting an upstream side and a downstream side of a papermaking raw material in a primary chamber, and a pump provided in the connection passage, a downstream side facing the tank downstream of the connection passage. The connection passage port is located on the upstream side of the papermaking raw material in the primary chamber from the water supply port opening facing the tank of the water supply pipe, and the pump forcibly returns the papermaking raw material on the downstream side to the upstream side by the pump, 2. An undissolved piece of the papermaking raw material is deflocculated.
A screen device as described. 3. A tank for storing a papermaking raw material, a flat screen provided in the tank and partitioned into a first chamber and a second chamber, and the flat screen located outside the screen. An impeller provided in the first chamber for agitating the papermaking raw material; and a substantially cylindrical screw provided in the second chamber and divided into a primary chamber and a secondary chamber and having a plurality of openings on a side surface. A stirring member positioned outside the substantially cylindrical screen to stir the papermaking raw material; and a foreign material such that a papermaking raw material inlet and a first room foreign matter outlet face the first chamber. An outlet is provided in the tank so as to face the primary chamber, and a papermaking raw material outlet is provided in the tank so as to face the secondary chamber, and the downstream side of the papermaking raw material in the primary chamber and before reaching the foreign matter outlet. A water supply pipe for supplying water into the tank so as to prevent the flow of the papermaking raw material; The papermaking raw material that has flowed into the primary chamber from the papermaking raw material inlet through the first chamber and the flat screen is agitated by the agitating member located outside the substantially cylindrical screen. Then, the papermaking raw material is caused to flow from the outside to the inside of the substantially cylindrical screen, and the carefully selected papermaking raw material is guided to the papermaking raw material outlet. By supplying water from the water supply pipe, the primary Downstream of the papermaking raw material in the chamber, blocking the flow of the papermaking raw material before reaching the foreign matter outlet, lengthening the storage time of the papermaking raw material in the tank, and increasing the undissolved pieces of the papermaking raw material. A screen device for deflocculating the screen. 4. A connection passage connecting the first chamber to the downstream side of the papermaking raw material in the primary chamber, and a connection port of the connection passage to the first chamber is provided so as to face substantially the center of the impeller. The downstream connection passage opening facing the tank downstream of the connection passage is located on the upstream side of the papermaking raw material in the primary chamber from the water supply pipe opening facing the tank of the water supply pipe, the connection passage 4. The screen apparatus according to claim 3, wherein the papermaking material on the downstream side is forcibly returned to the first chamber by the step (a) to disintegrate undissolved pieces of the papermaking material.