JPH08337988A - Pitch attaching inhibitor and pitch attaching inhibition using the same - Google Patents

Abstract

PURPOSE: To suppress or inhibit pitch attaching trouble by injecting a solution of a pitch attaching inhibitor obtained by mixing a cationic condensate with a cationic surfactant onto a part of a machine being in contact with a papermaking raw material. CONSTITUTION: A condensate of dicyandiamide with a polyalkylenepolyamine containing 2-5 nitrogen atoms is used as a A component and at least one kind of cationic surfactant selected from the group consisting of an alkyldimethylbenzylammonium chloride, an alkyltrimethylammonium chloride and an alkyldimethylenthylammonium ethylsulfate is used as a B component. The c components A and B are mixed in a weight ratio of A/B of (1/0.005)-(1/2.5), preferably (1/0.15)-(1/1.5) to prepare the objective pitch attaching inhibitor. An aqueous solution containing the pitch attaching inhibitor is injected onto at least a part of a papermaking machine being om compact with a raw material pulp or paper to prevent a pitch attaching trouble.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pitch adhesion preventive agent for suppressing and preventing pitch defects in pulp and paper manufacturing processes and a pitch adhesion preventing method using the same.

[0002]

2. Description of the Related Art Generally, there is a substance called pitch in the pulp and paper manufacturing process. This pitch is a non-water-soluble adhesive substance composed mainly of natural resins and gum substances released from wood, pulp and paper, and organic substances derived from additives and chemicals used in pulp and papermaking processes. . Generally, the pitch is colloidally dispersed during the pulp and papermaking process, especially in white water, but it has some external effects such as high shear, pH.
It is considered that the colloidal state is destroyed due to a rapid change in the water content, excessive addition of a sulfuric acid band, and the like, resulting in aggregation and enormous growth. Due to its adhesiveness, the pitch generated by this agglomeration and enlargement adheres to pulp and paper, and further adheres to manufacturing equipment such as fan pumps, pipes, chests, wires, felts and rolls, and When the paper is later peeled off and redeposited on the pulp or paper, stains and defects of the paper occur, which causes deterioration of quality and causes of pitch defects such as deterioration of productivity and workability due to occurrence of paper breakage. In recent years, as the number of chemicals used has increased due to the diversification of paper and the use of water used in the manufacturing process has become higher, the occurrence of pitch obstacles has increased more than ever and the form of occurrence has become complicated. It is the current situation.

[0003] As a method for preventing or reducing obstacles due to pitch adhesion in this papermaking process, a method of mechanically removing pitch, and a method of adding an adsorbing inorganic fine powder to a raw material to eliminate the tackiness of the pitch and making paper A method of making paper itself, a method of adding a surfactant to the raw materials to promote the dispersion of the agglomerated pitch particles, at the same time reducing the adhesiveness to prevent agglomeration, and making these paper into paper, pitch There is known a method of removing the compound from the system by dissolving it with an organic solvent. However, the removal method of the above method is very complicated. The pitch adhesion preventive agents used in the above and above methods are often added in a chest, a mixing chest, a machine chest or the like after pulper and refiner. As described above, most of the conventional pitch adhesion preventive agents are those that take out the pitch particles out of the system and those that disperse the pitch particles in the system, and are roughly classified into these two.

[0004]

The inorganic carrier, which is the above-mentioned adsorptive inorganic fine powder, has a dispersion and adsorption effect.
On the other hand, it causes wear of the heater, refiner, wire, roll doctor, clogging of press felt, and the effect is weak if it is not added in several places.
There are drawbacks such as the large amount of drug required to prevent pitch disorders. Further, by using an organic solvent in combination with the above-mentioned surfactant, the purpose of dissolving and dispersing the pitch particles in the pulp slurry, with the increase in the recovery rate of water,
There is a problem that accumulation of melted pitch, damage to papermaking equipment and tools, deterioration of working environment, and unpredictable pitch failure.

The present invention has been made in view of the above circumstances, and relates to a pitch adhesion preventing agent and a pitch adhesion preventing method using the pitch adhesion preventing agent, which can prevent obstacles due to pitch adhesion in the manufacturing process of pulp and paper. It is a thing.

[0006]

In order to achieve the above object, the first aspect of the present invention is a pitch adhesion preventive agent containing the following components (A) and (B). (A) Condensation product of dicyandiamide and polyalkylene polyamine. (B) Cationic surfactant.

A second aspect of the present invention is a pitch adhesion preventing method which comprises spraying the pitch adhesion preventing agent-containing solution onto at least a part of a papermaking machine which comes into contact with the pulp or paper raw material when manufacturing the pulp or paper. To do.

[0008]

In other words, the present inventors conducted a systematic study on the suppression of pitch adhesion generation in pulp and paper manufacturing processes. Then, in order to obtain an agent for preventing the adhesion of the pitch, as a result of trial using various compounds in combination, as a result, a cation-based condensate (A component) having a specific structure of dicyandiamide and a polyalkylene polyamine, and a cationic surfactant (B It has been found that an excellent pitch adhesion preventing effect can be obtained by using a pitch adhesion preventing agent in combination with (component). In particular, the mixing ratio (weight ratio) of the cationic condensate (component A) and the cationic surfactant (component B) is set within the range of component A: component B = 1: 0.05 to 1: 2.5. By doing so, a particularly excellent pitch adhesion preventing effect can be obtained without causing various problems.

As a method of using the above-mentioned pitch adhesion preventive agent, by spraying on a part of the papermaking machine which comes into contact with pulp or paper raw materials, the adhesion of pitch to the papermaking machine is remarkably suppressed to prevent the occurrence of pitch failure. The inventors of the present invention have found that they can do this and have reached the present invention.

Next, the present invention will be described in detail.

The pitch adhesion preventive agent of the present invention is obtained by using a cationic condensate having a specific structure (component A) and a cationic surfactant (component B).

The cation-type condensate having a specific structure (component A) is a condensation polymer obtained by subjecting dicyandiamide and polyalkylenepolyamine to a condensation reaction.

Among the above polyalkylene polyamines,
A polyalkylene polyamine containing 2 to 5 nitrogen atoms is preferable because it is easy to obtain and handle. Specific examples include ethylenediamine, diethylenetriamine and hexaethylenepentamine. These may be used alone or in combination of two or more.

The cation-type condensate having a specific structure (component A) can be obtained, for example, by subjecting the above dicyandiamide and polyalkylenepolyamine to a condensation reaction at a temperature of 150 to 200 ° C. by a known method. In this case, the reaction ratio of the above two is a molar ratio of dicyandiamide / polyalkylenepolyamine = 0.7 / 1 to 1 / 0.7.
It is preferable to set in the range of.

Examples of the cationic surfactant (component B) include alkyldimethylbenzylammonium chloride, alkyltrimethylammonium chloride, alkyldimethylethylammonium ethylsulfate and the like. These may be used alone or in combination of two or more. The alkyl group in the above-mentioned compounds is preferably an alkyl group having 8 to 18 carbon atoms from the viewpoint that it is difficult to obtain the desired performance when the number of carbon atoms described later is deviated, specifically, octyl. Group, lauryl group, stearyl group and the like. Examples of such a cationic surfactant include lauryl dimethyl benzyl ammonium chloride, stearyl trimethyl ammonium chloride, octyl dimethyl ethyl ammonium ethyl sulphate and the like.

The mixing ratio of the cationic condensate having the specific structure (component A) and the cationic surfactant (component B) is
By weight ratio, A component: B component = 1: 0.05 to 1: 2.5
It is preferable to set in the range of. Particularly preferably, A component: B component = 1: 0.15 to 1: 1.5. That is, if the blending ratio of the component B is less than 0.05, the wettability of the surface of the manufacturing equipment is poor, so that the coating of the component A becomes insufficient and the adhesion of the pitch component to the equipment can be effectively prevented. It will be difficult. Further, the mixing ratio of the B component is 2.
When it exceeds 5, the adhesion of the component A is poor and the coating is not sufficiently performed, so that it is also difficult to effectively prevent the adhesion of the pitch component to the devices.

Next, a pitch adhesion preventing method using the pitch adhesion preventing agent of the present invention will be described.

The pitch adhesion preventing method using the pitch adhesion preventing agent of the present invention is the pitch adhesion preventing method of the present invention, which is applied to at least a part of a papermaking machine which comes into contact with the pulp or paper raw material during the production of pulp or paper. This is a method for preventing the pitch from adhering to the felt, wire, roll, etc. of the papermaking machine by directly spraying the solution containing the agent.

In the above method, when the solution containing the pitch anti-adhesive agent is sprayed onto at least a part of the papermaking machine (for example, felt, wire, roll, etc.), the concentration of the pitch anti-adhesive agent in the solution is 0. 005-10% by weight
It is preferable to set it in the range of (hereinafter abbreviated as “%”), and especially when considering the cost, 0.005 to 0.05
It is preferable to set in the range of%. Especially 0.005
Within the concentration range of 0.05%, a sufficient pitch adhesion preventing effect can be obtained. That is, if the concentration of the pitch adhesion preventing agent is less than 0.005%, it is difficult to obtain the desired pitch adhesion preventing effect, and even if the concentration is more than 10%, the cost is increased and the effect is remarkably improved. Because it is not seen.

A solution containing the pitch adhesion preventive agent is generally an aqueous solution. As a spraying method, for example, a wire or a felt can be easily adhered to the pitch by press-fitting the solution into a washing water shower line. A method of spraying with a shower water onto a roll, a roll or the like can be given. Alternatively, a method of installing and spraying the above-mentioned spray for spraying the aqueous solution separately from the above-mentioned washing water shower line can be mentioned.

There is no particular limitation on the type of pulp and paper in the pulp and paper manufacturing process which is the subject of the pitch adhesion preventing method of the present invention, and all the pulp and paper currently manufactured and processed can be used. Paper is targeted and effective for these.

Next, examples will be described together with comparative examples.

First, the condensates A-1 to A-4 of four kinds of dicyandiamide and polyalkylenepolyamine were prepared by the combinations shown in Table 1 below. The condensate is
It was prepared by performing a condensation reaction by a known method in an atmosphere of a temperature of 180 ° C.

[0024]

[Table 1]

Further, the following three kinds of cationic surfactants B-1 to B-3 were prepared.

B-1: Lauryldimethylbenzylammonium chloride B-2: Stearyltrimethylammonium chloride B-3: Octyldimethylethylammonium ethylsulfate

Next, according to the combinations shown in Table 2 below, the above-mentioned condensates and cationic surfactants were mixed in the ratios (weight ratios) shown in the table to prepare the desired pitch adhesion inhibitors a to s. .

[0028]

[Table 2]

Then, a pitch adhesion preventing test was carried out using the above-mentioned pitch adhesion preventing agents a to s as shown below, and chemicals were selected. As a comparative control, the case where the pitch adhesion preventive agent was not sprayed (t in Table 2) was also performed. First, in a machine as shown in FIGS. 1 (A) and 1 (B), a pitch is previously attached (pitch attachment amount: 50).
0 mg / cm ² ) The surface of the paper making wire (wire) 1 was driven while spraying warm water from the warm water shower device 2, and the test felt 3 (100 cm ² ) was driven so as to make sliding contact with the wire 1. At this time, an aqueous solution of each pitch adhesion preventing agent shown in Table 2 was sprayed on the surface of the test felt 3 by the spraying device 9. In this way, the amount of pitch adhesion transferred from the wire 1 to the test felt 3 was measured. In FIG. 1, 4,5,6,7,8 are rolls. The above spraying conditions were set such that the amount of pitch adhesion preventive agent added was 0.05% of the total aqueous solution
/ M / min spray amount was sprayed for 5 hours. Then, after the spraying was completed, the pitch transferred to the surface of the test felt 3 was washed and extracted with toluene, and the weight thereof was weighed. The results are shown in Table 3 below.

[0030]

[Table 3]

From the results in Table 3 above, it is understood that the combination of A and B as the chemicals has the effect of preventing pitch adhesion because the pitch adhesion amount is small. Further, among the above combinations of A and B, it is found that the combination of the condensate A-2 and the cationic surfactant B-1 (f in Table 2) has a particularly high pitch adhesion preventing effect.

Next, in order to find a good mixing ratio of the condensate (A) and the cationic surfactant (B), particularly good results were obtained, and the condensate A-2 and the cationic surfactant B were obtained.
-1 combination (f in Table 2), the pitch adhesion inhibitor a _{21 in} which the compounding ratio (weight ratio) is appropriately changed
~ S ₂₁ was prepared. The mixing ratio is shown in Table 4 below.

[0033]

[Table 4]

A pitch adhesion test was conducted by using each of the pitch adhesion preventive agents a _{21 to} s ₂₁ obtained in the above mixing ratio.
It carried out by the machine shown in (A) and (B), and the weight of the pitch transferred to the surface of the test felt 3 was weighed in the same manner as above. The results are shown in Table 5 below.

[0035]

[Table 5]

From the results shown in Table 5 above, the blending ratio (weight ratio) of the condensate A-2 and the cationic surfactant B-1 was A-
It can be seen that the range of 2: B-1 = 1: 0.05 to 1: 2.5 is particularly good.

Next, a pitch adhesion preventing method in an actual machine test will be described.

[0038]

Example 1 The condensate A-2 and the polyalkylene polyamine B-1 were mixed in a weight ratio of A-2: B-1 = 1: 1.
A pitch adhesion preventive agent was prepared by mixing in a ratio of 5. Using this pitch adhesion preventing agent, the composition shown in FIG.
While spraying on a predetermined part of a papermaking machine (Duoformer F, papermaking speed 700 m / min) that manufactures core raw paper, papermaking [paper raw material (raw pulp slurry) flows in the direction of a thick arrow X] Produced base paper. That is, in the above papermaking machine, what is indicated by a dotted line is a wire,
What is indicated by the solid line is felt. Then, in the constituent portion a, the pitch adhesion inhibitor-containing aqueous solution was sprayed onto the felt surface by the shower 11 for spraying the felt surface which is in contact with the paper. In the constituent portion b, the pitch adhesion inhibitor-containing aqueous solution was sprayed on the felt surface by the shower 13 for spraying the felt surface in contact with the paper. Then, in the constituent portion c, the pitch adhesion preventing agent-mixed aqueous solution was sprayed onto the felt surface by the shower 15 for spraying the felt surface in contact with the paper. Further, in the constituent part d, the pitch adhesion inhibitor-containing aqueous solution was sprayed on the felt surface by the shower 16 for spraying the felt surface in contact with the paper. In FIG. 2, 18 is a suction box (suction / dewatering device), and 19 is a press shoe.
In addition, the above spraying conditions were set to 7 cc / m / min by setting the addition amount of the pitch adhesion preventing agent to 0.013% of the whole aqueous solution.
Was sprayed.

As a result, the amount of pitch adhered to the felt portion was considerably large before the spraying of the pitch adhesion inhibitor-containing aqueous solution. When this pitch adhesion inhibitor-containing aqueous solution was sprayed for 20 consecutive days, the felt surface was Almost no pitch adhered to it, and there was no need to stop the operation of this paper machine to wash the felt portion.

[0040]

Example 2 In the preparation of the above pitch adhesion preventive agent, the mixing ratio (weight ratio) of the condensate A-2 and the polyalkylene polyamine B-1 was set to a ratio of A-2: B-1 = 1: 0.05. Replaced with. Further, the addition amount of the pitch adhesion preventing agent was changed to 0.005% of the whole aqueous solution. Other than that, the core raw paper was manufactured under the same conditions as in Example 1 by the paper machine having the configuration shown in FIG.

As a result, the amount of pitch adhered to the felt portion was considerably large before the spraying of the pitch adhesion preventing agent-containing aqueous solution. When the pitch adhesion preventing agent containing aqueous solution was continuously sprayed for 20 days, the felt surface was Almost no pitch adhered to it, and there was no need to stop the operation of this paper machine to wash the felt portion.

[0042]

Example 3 In the preparation of the above-mentioned pitch adhesion preventive agent, the mixing ratio (weight ratio) of the condensate A-2 and the polyalkylene polyamine B-1 was set to a ratio of A-2: B-1 = 1: 2.5. Replaced with. Other than that, the core raw paper was manufactured under the same conditions as in Example 1 by the paper machine having the configuration shown in FIG.

As a result, before the spray of the pitch-adhesion-preventing agent-containing aqueous solution, the amount of pitch adhered to the felt portion was considerably large, but when this pitch-adhesion-preventing agent-containing aqueous solution was sprayed for 20 consecutive days, the felt surface Almost no pitch adhered to it, and there was no need to stop the operation of this paper machine to wash the felt portion.

[0044]

Example 4 The condensate A-2 and the polyalkylene polyamine B-1 were mixed in a weight ratio of A-2: B-1 = 1: 1.
A pitch adhesion preventive agent was prepared by mixing in a ratio of 5. Using this pitch adhesion preventing agent, the composition shown in FIG.
Paper was manufactured (the raw pulp slurry flows in the direction of the thick arrow Y) while spraying onto a predetermined portion of a paper manufacturing machine (papermaking speed: 700 m / min) that manufactures the printing base paper. That is, in the above papermaking machine, what is indicated by the dotted line is a wire, and what is indicated by the solid line is a felt. Then, in the constituent portion a ′, the pitch adhesion inhibitor mixture aqueous solution was sprayed onto the felt surface by the spraying shower 20 at one location. Further, in the constituent part b ′, the pitch adhesion inhibitor mixed aqueous solution was sprayed onto the felt surface by the spraying shower 21 at one place. Then, in the constituent portion c ′, the pitch adhesion preventing agent-containing aqueous solution was sprayed onto the felt surface by the spraying shower 22 at one place. Further, in the constituent portion d ′, the pitch adhesion inhibitor mixture aqueous solution was sprayed onto the felt surface by the spraying shower 23 at one place. In FIG. 3, 24 is a suction box (suction / dewatering device), 25 is a press roll, and 26 is a center roll. Further, the above spraying conditions are such that the addition amount of the pitch adhesion preventing agent is 0.01
%, And sprayed at a spray rate of 5 cc / m / min.

As a result, the top plate 2 of the suction box 24 shown in FIG.
The pitch adhered to 4a, and the felt caused hair loss due to it, but when this pitch adhesion inhibitor mixture aqueous solution was sprayed, there was almost no pitch adhesion to the top plate 24a, and hair loss occurred. There was no trouble caused by.

[0046]

Example 5 In the preparation of the above pitch adhesion preventive agent, the mixing ratio (weight ratio) of the condensate A-2 and the polyalkylene polyamine B-1 was set to a ratio of A-2: B-1 = 1: 0.05. Replaced with. Further, the addition amount of the pitch adhesion preventing agent was changed to 0.005% of the whole aqueous solution. Except for this, the printing base paper was manufactured under the same conditions as in Example 4 using the paper machine having the configuration shown in FIG.

As a result, the top plate 2 of the suction box 24 shown in FIG.
The pitch adhered to 4a, and the felt caused hair loss due to it, but when this pitch adhesion inhibitor mixture aqueous solution was sprayed, there was almost no pitch adhesion to the top plate 24a, and hair loss occurred. There was no trouble caused by.

[0048]

Example 6 In the preparation of the above pitch adhesion preventing agent, the mixing ratio (weight ratio) of the condensate A-2 and the polyalkylene polyamine B-1 was set to the ratio of A-2: B-1 = 1: 2.5. Replaced with. Further, the addition amount of the pitch adhesion preventing agent was changed to 0.005% of the whole aqueous solution. Except for this, the printing base paper was manufactured under the same conditions as in Example 4 using the paper machine having the configuration shown in FIG.

As a result, the top plate 2 of the suction box 24 shown in FIG.
The pitch adhered to 4a, and the felt caused hair loss due to it, but when this pitch adhesion inhibitor mixture aqueous solution was sprayed, there was almost no pitch adhesion to the top plate 24a, and hair loss occurred. There was no trouble caused by.

[0050]

INDUSTRIAL APPLICABILITY As described above, the pitch adhesion preventive agent of the present invention contains a specific cationic condensate (component A) and a cationic surfactant (component B). It has an excellent effect of suppressing the occurrence of pitch defects in machines and equipment. Then, by spraying the pitch adhesion preventive agent on the papermaking machine and the tools, the adhesion of the pitch to the papermaking machine and the tools can be significantly suppressed. Thus, by using the pitch adhesion prevention method of the present invention, it is possible to suppress the occurrence rate of damage to papermaking equipment and tools due to pitch adhesion, and in the past, in order to remove the adhered pitch,
Although it was necessary to stop the operation and wash the paper machine during a short period of operation, it is not necessary to stop the operation and perform the washing, which greatly improves the workability of manufacturing. Therefore, the quality of the pulp and paper products obtained by the pitch adhesion preventing method of the present invention is improved and the practical value is very high.

[Brief description of drawings]

FIG. 1A is a side view showing a machine used for a pitch adhesion prevention test, and FIG. 1B is a plan view thereof.

FIG. 2 is a schematic diagram showing the configuration of a papermaking machine that manufactures core raw paper.

FIG. 3 is a schematic diagram showing a configuration of a papermaking machine that manufactures printing base paper.

FIG. 4 is a cross-sectional view showing a suction box which is a component of the papermaking machine.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Daiji Tanigasaki 98-43 Jimbohara, Kamisato-cho, Kodama-gun, Saitama (72) Inventor Katsuya Ogawa 2-11-7-306 Minami-cho, Warabi-shi, Saitama

Claims (5)

[Claims] 1. A pitch adhesion preventing agent comprising the following component (A) and component (B). (A) Condensation product of dicyandiamide and polyalkylene polyamine. (B) Cationic surfactant. 2. The number of nitrogen atoms in the polyalkylene polyamine used as the component (A) is 2 to 5.
The described pitch adhesion preventing agent. 3. The cationic surfactant as the component (B) is at least one cationic surfactant selected from the group consisting of alkyldimethylbenzylammonium chloride, alkyltrimethylammonium chloride and alkyldimethylethylammonium ethylsulfate. The pitch adhesion preventive agent according to claim 1 or 2. 4. The mixing ratio of the component (A) and the component (B) is
By weight ratio, A component: B component = 1: 0.05 to 1: 2.5
The pitch adhesion preventive agent according to any one of claims 1 to 3, which is set in the range of. 5. When producing pulp or paper, the pitch anti-adhesion agent-containing solution according to any one of claims 1 to 4 is provided in at least a part of a papermaking machine that comes into contact with the pulp or paper raw material. A method for preventing pitch adhesion, which comprises spraying.