JPH086079Y2 - Papermaking screen - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention effectively removes impurities from pulp raw materials, such as pulp raw materials and other papermaking raw material adjustment lines, which contain a lot of foreign substances in papermaking equipment, and removes dust to be released. The present invention relates to a pressure screen equipped with a screen basket.

[Prior Art] Generally, in a papermaking facility such as a pulp plant and a used paper treatment, a screen is used to carefully select raw materials, that is, to remove foreign matters and other dusts in a fiber suspension which is a raw material, in order to improve processing ability. In addition, it is used as an internal pressure type pressure screen in which the raw material is pressed into the screen basket in the closed casing from the inside to the outside, or an external pressure type pressure screen in which the raw material flows in the opposite direction, and the effective recovery of useful fibers and the working efficiency are further enhanced. Therefore, it is known to rotatably deploy a bladed agitator along the screen basket.

[Problems to be solved by the device]

In this type of screen, the raw material on the inlet side swirls and moves to the reject side, while the slits or round holes formed in the screen basket allow useful fibers to pass through and collect, and foreign substances such as impurities that cannot pass through do not pass. However, since the agitator is rotating, the untreated raw material sent from the inlet side is remixed with these foreign substances, and discharged as lees and a large amount of useful fibers are contained in the screen. There was a problem that the original function deteriorated and the processing efficiency could not be improved. In particular, in the past, in order to collect useful fibers in the reject, it has been practiced to stack several stages to condense the foreign substances to reduce the final discharged reject amount, but the screen reject amount increases and the equipment also increases. There is a drawback that it becomes large and requires a pump, maintenance is complicated, which leads to an increase in cost, and the cost is high in terms of equipment.

The present invention is intended to eliminate these conventional problems, and it significantly separates useful fibers from foreign substances, reduces the amount of reject, simplifies the reject process, and greatly improves the separation function of the screen. It is an object of the present invention to provide a screen, which has a simple structure and is inexpensive, which facilitates efficient selection processing.

Further, in the present invention, it is possible to separate the ink and useful fibers desired as a deinking plant, and especially by adjusting the amount of dilute water and the reject rate, the ink particles are guided to the outlet side together with the fine fibers, and the ink particles are provided on the reject side. Another purpose is to provide a screen device that is effective in recovering only long fibers having a low content.

[Means for solving the problem]

The present invention is a cylindrical screen basket in which a casing 3 having a raw material inlet 1 and an outlet 2 is partitioned into a foreign matter collection chamber 11 connected to the raw material inlet 1 and a selected substance chamber 12 connected to the outlet 2. 5, in the papermaking screen with a agitator 6 which is rotatably provided along the cylindrical screen basket 5, to approach each agitator ring ₆₁ which is formed at a plurality interval to said agitator 6 clamping隘部The papermaking screen is characterized in that the casing 3 is provided with 3 ₁ ...

[Embodiment] An embodiment of the present invention will be described with reference to FIGS.
A cylindrical screen basket 5, which is formed by partitioning a casing 3 having a raw material inlet 1 and a raw material outlet 2 into a foreign matter collection chamber 11 connected to the raw material inlet 1 and a selected substance chamber 12 connected to the outlet 2. in papermaking screen having a agitator 6 which is rotatably provided along a cylindrical screen basket 5, the clamping隘部3 ₁ ... approaching each agitator ring ₆₁ which is formed at a plurality interval to said agitator 6 This is a papermaking screen in which the foreign matter collection chambers 11 are provided in the casing 3 and are communicated in a plurality of stages.

In this case, as the clamping隘部3 ₁ consisted tapered conical portion whose diameter gradually decreases downward formed in the casing 3, the partition portion is narrowed at the location of the agitator rings _61, thereto A water supply nozzle 13 for forming a water film is provided, and the water supply nozzle 13 is connected and connected to a water supply pipe 15 having a valve 14 (FIGS. 3 and 5 (A)), or FIG. 5 (B).
As shown in (C), the pocket 13 ₁ having the water supply nozzle 13 or the water supply ring 13 ₂ may be provided on the inner circumference of the casing 3 to form the sandwiching portion 3 ₁ . The clamping隘部3 ₁ multiple stages to form a zone for applying a push-back force to material flow toward the terminal end side from the starting end of the screen basket, the short fibers feedstock was a pass in each zone passed through a screen, The long fibers that do not pass through the screen are introduced together with foreign substances into the screening process.

Further, the screen mesh of the screen basket 5 is, for example, a round hole of 1.0 to 5.0φ or a slit of 0.1 to 1.0 mm, which divides the foreign matter collection chamber 11 and the selected substance chamber 12 into a screen basket. 5 the outer peripheral agitator 6 disposed at equal intervals or at predetermined intervals in the agitator ring ₆₁ to the provided rotatably configured in external pressure type screen are as raw material passage capacity is equal, but when the inner pressure screen The inner and outer circumference positions are opposite to those of the previous example. Further, the tail discharge port 8 is provided at the lowermost part of the foreign matter collection chamber 11 and is connected to the tail discharge path as shown in FIG.
It is connected to the post-treatment system chest 10, removes foreign substances in the raw material with the screens 16 and 17, rejects foreign substances are circulated in the return path 18, and foreign substances are discarded to the outside of the system, but the timer (Fig. It is also possible to intermittently open all at once (not shown) so that light items can be discharged together.

The outlet 2 is a system in which the useful fiber that flows out is processed through the chest 4 in the floatation section 7, the fiber recovered in the chest 9 is diluted, and then processed by the centrifugal cleaner 19.

In the figure, 20 is the pulping process, 21 is the rough selection part, 22 is the disaggregation part, and 23 is
Is a pump.

In the example shown in FIG. 6, the inner circumference of the casing 3 is fitted with an inner cylinder-shaped inner cylinder, and the pocket portion 13 is provided.
This is an example in which ₁ is formed between casings 3 and this is used for a water supply chamber. Moreover, as the agitator ring _61, in which the material flows to the outer periphery as shown in FIG. 7 with the inclined protrusions 24 or depressions pushed upward, Giza surface 25 or unevenness for agitation if necessary A surface may be attached.

In these examples, as the casing 3, the raw material inlet 1 for tangentially supplying the fiber suspension into the casing, the outlet 8 for reject discharge for continuously discharging in the tangential direction or the axial direction, and the screening. A closed cylinder provided with an outlet 2 for deriving useful fibers of the subsequent stock is used as a screen in which the screen basket 5 and an agitator 6 serving as a rotor are concentrically provided. The good quality raw material that is agitated by the rotating agitator 6 passes through the screen plate and becomes the accept raw material.
It is prevented by the interaction between pressurization and negative pressure.

[Action]

Then, the raw material of the fiber suspension is supplied from the raw material inlet 1 to the foreign matter recovery chamber 11 in the casing 3, and the agitator 6 rotating along the screen basket 5 increases the flow velocity of the raw material and selects useful fibers from the screen. the cleaning effect of the screen plate is passed into the substance chamber 12 with continuously performed, the foreign matter raw materials separated off continuously derived from the outlet 2, further reject including foreign matter of each clamping隘部3 ₁ zone In order to prevent the foreign matter from being mixed, undisintegrated pieces are disentangled with an agitator 6, and are gradually collected as useful fibers from the screen to the selected substance chamber 12 and sent to the next process, but the screen reject amount is reduced as much as possible. The dissociation and dust removal treatment can be effectively performed by reducing the number of operations and operating in a continuous system.

[Advantages of the Invention] In the present invention, the casing is provided with a sandwiching portion that respectively approaches the agitator ring formed at a plurality of intervals on the agitator, and the foreign matter collecting chambers are communicated in a plurality of stages to condense the foreign matter. It is remarkably simple, and the foreign substances do not spread over the entire room and are treated in each divided area to significantly improve the screening ability, enabling efficient screen work, increasing the foreign substance concentration, and reducing the screen reject amount. In addition to simplifying the equipment of the screen, unremoved pieces of the screen reject are loosened in the screen body as much as possible, and the loosened raw material is extracted to the exit side, and the fiber content is less mixed into the tail and the useful fiber is collected. The rate is also increased, and the installation of disintegrators in the subsequent process can be reduced, so running costs can be reduced. The composition is simple, and there is a practical effect such that the ink and the fiber can be efficiently classified in the deinking plant.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view, and FIG.
FIG. 1 is a cutaway plan view taken along the line I--I of FIG. 1, FIG. 3 is a partially enlarged vertical sectional view, FIG. 4 is a system explanatory view, and FIGS.
(C) is a longitudinal sectional view of another embodiment of the main part, FIG. 6 is a longitudinal sectional view of another embodiment, and FIG. 7 is a perspective view of a part of the agitator ring. 1 ... Raw material inlet, 2 ... Outlet, 3 ... Casing,
3 ₁ …… Clamping part, 4 …… Chest, 5 …… Screen basket, 6 …… Agitator, 6 ₁ …… Agitator ring,
7 ... Flotation part, 8 ... Discharge port, 11 ... Foreign matter collection chamber, 12 ... Selected material chamber, 13 ... Water supply nozzle, 14 ...
Valve, 15 …… Water supply pipe.

Claims (4)

[Scope of utility model registration request] 1. A casing (3) having a raw material inlet (1) and an outlet (2) is connected to a foreign matter collection chamber (11) connected to the raw material inlet (1) and to the outlet (2). A papermaking screen comprising: a cylindrical screen basket (5) which is partitioned and formed in a selective substance chamber (12); and an agitator (6) rotatably provided along the cylindrical screen basket (5), The casing (3) is provided with a sandwiching portion (3 ₁ ) which approaches the agitator ring (6 ₁ ) formed at a plurality of intervals on the agitator (6) and the foreign matter collection chamber (11) is divided into a plurality of stages. A papermaking screen characterized by being connected. 2. The sandwiching portion (3 ₁ ) comprises a tapered conical portion formed in the casing (3) and having a diameter gradually decreasing downward, and a water supply nozzle (13) for forming a water film is provided. The papermaking screen according to claim 1, which is provided. 3. The papermaking screen according to claim 1, wherein the sandwiching portion (3 ₁ ) is a water supply ring having a water supply nozzle (13) provided on the inner circumference of the casing (3). Wherein said agitator ring ₍₆₁₎ is papermaking screen according to claim 1, wherein those having a sloped projections or recesses push the material flows upwards in the outer periphery thereof.