JP2990202B2 - Method for improving the peelability of wet paper from a stone roll - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for improving the removability of a wet paper web from a stone roll in a press part of a dewatering section of a wet paper web during a paper making process.

[0002]

2. Description of the Related Art The pulp and paper industry has been suffering from pitch trouble for many years in each step starting from the pulping step. In particular, with the promotion of closed systems such as the improvement of the reuse rate of white water in recent years, and the diversification of paper as its product along with raw materials, the types of chemicals used have been diversified, and their amounts have also increased. The situation of pitch trouble is becoming more complicated.

[0003] Generally, the papermaking process comprises pulp preparation, papermaking (dewatering, drying), and, if necessary, coating, etc. In the dewatering process, most of the water in the stock is removed by a wire part. To form a wet paper web, which still contains a lot of water, and if the wet paper thus obtained is heated and dried as it is, a large amount of steam is required, which is economically disadvantageous. Is sent to the press part (squeezing department)
After being dehydrated by a mechanical press, it is sent to a dry part (drying section). Here, the dirt due to the pitch attached to the members around the paper machine, particularly to the members constituting the wet part consisting of the wire part and the press part, directly affects the operation efficiency and the quality of the final product in paper manufacturing, and is therefore serious. Problem.

[0004] Here, the above-mentioned pitch is a general term for resinous substances contained in pulp (GP, TMP, KP, DIP, etc.) in paper production, and is initially dispersed in paper stock. However, they coagulate due to changes in pH, temperature, ionic strength and the like, become sticky substances, and cause various troubles in the papermaking process. The origins of such pitches are largely as follows: first, resin acids, fatty acids,
Alcohol, unsaponifiables, or those that have been altered in the pulping process; secondly, adhesives from waste paper pulp, ink vehicles, etc .; and thirdly, starch as an internal additive during manufacture, synthetic paper strength. It can be classified into three types, ie, unfixed components such as an enhancer and a sizing agent.

Conventionally, in order to prevent or reduce pitch troubles, for example, Japanese Patent Application Laid-Open No. 63-264
No. 993, JP-A-3-244698, JP-A-4-352898, JP-A-4-202299, JP-A-4-300383, and the like. Although the pitch control agent is added to the pulp slurry by a chest after a pulper, a chest after a refiner, a machine chest, or the like, it is conventionally impossible to completely prevent the pitch from adhering to a papermaking tool. Further, Japanese Patent Application Laid-Open No. 2-189595 discloses a method of preventing pitch from being attached to felt used in a press part.

In particular, a stone roll (including natural stones and artificial stones) such as a center roll of a press part directly contacts a paper web, and the subsequent process is an open draw, so that the paper web is free. In the state, if the pitch is attached to the stone roll, the paper roll is picked up by the roll, the peeling line descends and the paper breaks, it takes a long time to pass the paper, and the productivity is reduced. I have. That is, specifically, the pitch adheres to a papermaking tool, a dewatering part, a press roll, and the like, and accordingly, peeling, perforating, cutting the paper,
The transfer of the pitch to the paper web, the removal from the doctor blade, etc. occur, and the above tendency is particularly strong in the case of paper having a small basis weight and low strength. Therefore, conventionally, at the beginning of making,
Although the company has taken measures such as changing the raw material composition and the ratio of internal additives, it has not achieved satisfactory results at present.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for improving the releasability of a wet paper web from a stone roll in a press part of a dewatering section of a wet paper web during the above-mentioned paper making process. Aim.

[0008]

Method for improving the releasability of the stone roll according to the present invention, in order to solve the above-mentioned object, in the papermaking process, in a press part, (a) the general formula (I)

[0009]

Embedded image

(Wherein R is an alkyl group having 8 to 22 carbon atoms)
Or an alkenyl group, and AO is oxy having 2 to 4 carbon atoms.
Represents an alkylene group, and n + m is an integer of 2 to 50
You. A) a polyoxyalkylene alkylamine represented by the general formula (II):

[0011]

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(In the formula, even if A is substituted with a hydroxyl group,
Shows good divalent lower hydrocarbon groups. )) And an anti-fouling agent containing (c) a nonionic surfactant (excluding polyoxyalkylene alkylamine) as an active ingredient, is applied to a stone roll or a felt to prevent pitch deposition. It is characterized by preventing.

The stone roll antifouling agent used in the present invention comprises a polyoxyalkylenealkylamine, an organic phosphonic acid and a nonionic surfactant (excluding polyoxyalkylenealkylamine) as active ingredients, and among them, polyoxyalkylenealkyl The amine has the general formula
(I)

[0014]

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(Wherein R represents an alkyl group or alkenyl group having 8 to 22 carbon atoms, AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n + m is an integer of 2 to 50). It is.

The above-mentioned polyoxyalkylene alkylamine is obtained by adding an alkylene oxide to a saturated or unsaturated aliphatic amine having 8 to 22 carbon atoms such that the added mole number becomes 5 to 30 moles. be able to. Examples of such an aliphatic amine include octylamine, decylamine, laurylamine, myristylamine, palmitylamine, stearylamine, and oleylamine. These may be used alone or as a mixture of two or more. Among these, laurylamine, myristylamine, palmitylamine, stearylamine, oleylamine and the like are preferably used.

In the above polyoxyalkylene alkylamine, the oxyalkylene group represented by AO is one or a combination of two or more selected from oxyethylene, oxypropylene and oxybutylene. In the case of the above combination, such a polyoxyalkylene group may be a group consisting of either a block copolymer or a random copolymer.

In the present invention, in particular, the oxyalkylene group is preferably an oxyethylene group and / or an oxypropylene group, of which the number of moles added is preferably in the range of 10 to 25 mol.

The organic phosphonic acid used in the present invention is
General formula (II)

[0020]

Embedded image

(Wherein A represents a divalent lower hydrocarbon group which may be substituted with a hydroxyl group ).

Specific examples of such organic phosphonic acids include, for example, 1-hydroxyethylidene-1,1-diphospho.
Fonic acid and the like . In the present invention, the organic phosphonic acid includes salts thereof, and examples of such salts include sodium salts, potassium salts, and ammonium salts. Organic phosphonic acids and salts thereof contribute to control of metal ions, such as calcium ions, aluminum ions, iron ions, and copper ions, which are one of the core components during pitch aggregation.

Further, in the present invention, a nonionic surfactant (excluding polyoxyalkylene alkylamine) used as one of the active ingredients of the stone roll antifouling agent.
Is preferably an alkylene oxide adduct to a compound having active hydrogen (excluding alkylamine). The polyoxyalkylene alkylamine is an alkylene oxide adduct to an alkylamine.

In the present invention, examples of the compound having active hydrogen include aliphatic alcohol, alkylphenol, polyhydric alcohol fatty acid ester such as sorbitan fatty acid ester, glycerin fatty acid ester, pentaerythritol fatty acid ester, fatty acid, fatty acid amide and the like. Examples can be given. Here, the fatty acid may be either saturated or unsaturated.

Accordingly, in the present invention, as described above, the nonionic surfactant comprises an alkylene oxide adduct to a compound having active hydrogen, such as an alkylene oxide to an aliphatic alcohol. Polyoxyalkylene alkyl ethers that are oxide adducts, polyoxyalkylene alkyl phenyl ethers that are adducts to alkylphenols, polyoxyalkylene sorbitan fatty acid esters that are adducts to sorbitan fatty acid esters, and adducts to glycerin fatty acid esters Polyoxyalkylene glycerin fatty acid ester, polyoxyalkylene pentaerythritol fatty acid ester which is an adduct to pentaerythritol fatty acid ester, polyoxyalkylene fatty acid ester which is an adduct to fatty acid Ether, it may be mentioned polyoxyalkylene fatty acid amides adducts to fatty acid amide.

In the present invention, the alkylene oxide adduct to the compound having active hydrogen as the nonionic surfactant has an overall molecular weight of 800 to 2,000 from the viewpoint of low foaming property and high oil and fat solubility. In the range, as the oxyalkylene group contained in the molecule,
Those composed of one or a combination of two or more selected from an oxyethylene group, an oxypropylene group and an oxybutylene group are preferably used. The alkylene oxide adduct having two or more oxyalkylene groups contained in the molecule may be either a block copolymer or a random copolymer.

The polyoxyalkylene alkylamine and the nonionic surfactant described above can be produced according to a conventional method, but commercially available products can also be used. Commercially available organic phosphonic acid can also be used.

The stone roll antifouling agent used in the present invention is preferably a polyoxyalkylene alkylamine, an organic phosphonic acid and a nonionic surfactant, which are active ingredients, in a weight ratio of 60:30:10 to 30. :
Those in the range of 55:15 are preferred. These active ingredients are usually used as they are by diluting them to about 10-fold.

Next, the method of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a roll configuration of a transformer type 2-nip combined press as an example of a roll configuration of a press part in a dewatering section of a paper machine.
Are No. 2 press stone roll 4 and No. 2 in FIG.
The perspective view of the main part near 3 press stone roll 6 is shown.

As shown in FIG. 1, the wet paper web 7 sent from the wire part (not shown) to the press part is stacked on the pickup felt 9 via the pickup roll 1 and is pressed by the No. 1 press and the No. 2 press. Water is pressed through a press, and then through a No. 3 press. Meanwhile, No.
An open draw is formed between the press roll 2 and the paper roll 11. Reference numeral 8 is No. 1 press felt, and reference numeral 10 is No. 3 press felt.

According to the present invention, it is possible to prevent the pitch from being deposited on the surface of the stone roll by applying the above-described soil roll stain preventive agent to the stone roll in the press part during the paper making process. .

For example, as shown in FIG. 2, a doctor blade 15 is provided in contact with the No. 2 press stone roll 4, and this doctor blade removes fine substances and scum adhering to the surface of the roll. To keep the roll surface clean.

According to the present invention, the doctor blade 1
5, a shower pipe 12 is provided so that the stone roll antifouling agent can be poured onto the surface of the stone roll 4, and the stone roll antifouling agent is diluted with a stock solution or 2 to 10 times. By feeding the liquid from the chemical solution tank 14 to the shower pipe 12 by the metering pump 17a and pouring uniformly and continuously over the entire width of the stone roll 4, it is possible to prevent the pitch from being deposited on the surface of the stone roll. The amount of the antifouling agent added to the stone roll is appropriately selected according to the size of the apparatus, the driving speed of the web, and the like.
cc / min.m, preferably 5 to 20 cc
/Min.m.

Similarly, for the No. 3 press stone roll 6, the doctor blades 21, 2
2 is provided with a shower pipe 19 and a dropping device 20, and a stone roll antifouling agent is sent from the chemical tank 14 by the metering pump 17 b and can be poured uniformly and continuously over the entire width of the stone roll 6. .

On the other hand, generally, during the papermaking process, in a press part, a felt detergent is sent from the detergent tank 13 to the shower pipe 18 by the metering pump 23, and the felt 1
Pour to zero to clean the felt. Here, the stone roll antifouling agent according to the present invention is not only excellent in roll antifouling effect, but also
As it has an excellent effect as a felt cleaning agent,
In the present invention, instead of the felt cleaning agent, the above-mentioned stone roll stain preventive agent is used, and is similarly sent from the tank 13 to the shower pipe 18 by the metering pump 23 and poured into the felt 10. In addition, pitch can be prevented from being deposited on the surface of the stone roll.

However, it is a matter of course that a felt detergent composed of a different component may be used for washing the felt, if necessary. Such a felt detergent is, for example, kerosene. And those comprising an acidic solvent and an acidic cleaning agent.

[0038]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by the examples. still,
In Examples, the transformer type 2 nip combined press described above was used as the press part of the dewatering unit.
The composition shown in Preparation Example 1 below was used after being diluted with a 30% by weight aqueous solution. The numbers in parentheses indicate the number of oxyalkylene units added immediately thereafter.

[0039] (Formulation Example 1) poly (15) oxyethylene poly (2) oxypropylene Oh Reiruamin (block copolymer) 35 parts by weight of 1-hydroxyethylidene-1,1-diphosphonic acid 20 parts by weight poly (20) oxy sorbitan monolaurate es ether 45 parts by weight

Example 1 When starch and a synthetic paper strength agent were internally added to a pulp slurry and used, the peeling of the wet paper from the No. 2 press stone roll 4 became poor, and the wet paper was collected on the stone roll. As a result, the peeling line descended and the paper was cut, and the paper could not be passed.
Then, by pouring a stone roll antifouling agent from the shower pipe 12 onto the surface of the stone roll, the removal of the wet paper web to the stone roll is eliminated, and the peeling line is also increased.
The draw was also greatly slackened, and operability was greatly improved. Also,
As shown in FIG. 2, by pouring the above-mentioned stone roll antifouling agent onto the surface of the felt from the shower pipe 18 close to the felt, the removal of the wet paper web to the stone roll is eliminated, and the pitch to the felt is further reduced. Adhesion was also significantly reduced.

Example 2 Due to the problem of debris removal and pitch loss from the doctor blades of the press stone rolls 4 and 6, shower pipes 12 and 19 and a dropping device 20 adjacent to the stone rolls were provided. By pouring the antifouling agent onto the surface of the stone roll, the above-mentioned problems were almost solved and paper breakage and heavy defects were reduced.

Example 3 By pouring a stone roll antifouling agent onto the surface of the stone roll 4 or the felt 10 30 minutes before paper passing, the paper peeling from the stone roll is improved, and the time required for paper passing is shortened. As a result, productivity was improved.

[0043]

As described above, according to the present invention, during the papermaking process, in the press part of the dewatering section of the wet paper, a stone roll antifouling agent containing a predetermined component as an active ingredient is poured onto the surface of the stone roll or felt. Thereby, peeling of the wet paper from the stone roll is remarkably improved, and thus productivity is improved.

[Brief description of the drawings]

FIG. 1 shows a roll configuration of a transformer-type 2-nip combined press in a dewatering section of a paper machine.

FIG. 2 is a perspective view of a main part near No. 2 and No. 3 press stone rolls in FIG.

[Explanation of symbols]

1: Pickup roll, 2: No. 1 press roll, 3
… No. 2 press roll, 4… No. 2 press stone roll, 5… No. 3 press roll, 6… No. 3 press stone roll, 7… wet paper, 8… No. 1 press felt, 9…
Pickup felt, 10 ... No.3 press felt,
11 ... paper roll, 12 ... shower pipe, 13 ...
Felt detergent tank, 14 ... Chemical solution tank, 15, 16
... Doctor blade, 17a, 17b ... Metering pump, 1
8, 19: shower pipe, 20: dripping device, 21, 2
2 ... Doctor blade, 23 ... Metering pump.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takatomo Shibuya 2-2-1 Nankocho, Ishinomaki-shi, Miyagi Japan Inside the Ishinomaki Mill of Nippon Paper Industries Co., Ltd. (72) Inventor Masatoshi Mogi 2-2-2 Nankocho, Ishinomaki-shi, Miyagi No. 1 Inside the Ishinomaki Mill of Nihon Paper Industries Co., Ltd. (56) References JP-A-3-260190 (JP, A) JP-A-4-202299 (JP, A) JP-A-55-45857 (JP, A) JP-A-60-119289 (JP, A) JP-A-50-160502 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D21F 1/32 D21C 9/08 D21F 3/08

Claims (2)

(57) [Claims] (1) In a papermaking process, in a press part: (a) General formula (I) (Wherein, R represents an alkyl group or alkenyl group having 8 to 22 carbon atoms, and AO represents an oxyethylene group and an oxypropyl group.
Represents a len group , and n + m is an integer of 2 to 50. ) Polyoxyalkylene alkylamine block
Copolymer , (b) general formula (II) (Wherein A represents a divalent lower hydrocarbon group which may be substituted with a hydroxyl group) and a compound (c) having active hydrogen (excluding alkylamine ).
Good. Non-ion consisting of alkylene oxide adduct to
A method for improving the releasability of wet paper from a stone roll, comprising applying a stone roll antifouling agent containing a surfactant as an active ingredient to the stone roll or felt to prevent pitch accumulation. 2. A wet paper method for improving peelability from the stone roll according to claim 1 the organic phosphonic acid is 1-hydroxyethylidene-1,1-diphosphonic acid.