WO2017210974A1

WO2017210974A1 - Device and method for capturing sticky materials in pulping and papermaking system

Info

Publication number: WO2017210974A1
Application number: PCT/CN2016/092389
Authority: WO
Inventors: 张福山; 王祥槐; 杨春才
Original assignee: 瑞辰星生物技术（广州）有限公司
Priority date: 2016-06-06
Filing date: 2016-07-29
Publication date: 2017-12-14
Also published as: CN105887551B; CN105887551A

Abstract

A device for capturing sticky materials in a pulping and papermaking system, comprising a reaction vessel comprising an accommodating cavity (110) for accommodating a papermaking pulp; and an absorption test piece (200) having an absorption surface and used for adsorbing granular sticky materials in a papermaking pulp flowing through the absorption test piece, the absorption surface of the absorption test piece (200) being located inside the accommodating cavity (110). A method using the device comprises allowing a papermaking pulp at a pre-determined sampling point in the pulping and papermaking system to flow through the surface of the absorption test piece and have an adsorption reaction with the absorption test piece so that granular sticky materials in the papermaking pulp are adsorbed to the surface of the absorption test piece. The capturing device uses the reaction vessel to provide support for the absorption test piece and can withstand the impact of the flow of the papermaking pulp in every direction.

Description

Capturing device and method for glue in paddle papermaking system

Technical field

The present invention relates to the field of pulp and papermaking technology, and more particularly to a device and method for capturing glue in a pulp and paper system. Background technique

A growing problem facing the current pulp and paper industry is how to control the adverse effects of stickies deposited in the pulp on the production process and product quality. These stickies mainly come from three aspects: one is the lipophilic substances originally present in papermaking fibers, such as fatty acids, resin acids, fatty acid esters, alcohols and alcohol esters; the other is the introduction of waste paper itself when making paper on waste paper. Coating adhesives, printing inks, hot melt adhesives, pressure sensitive adhesives, etc.; Third, certain chemicals added during the pulping and papermaking process, such as reinforcing agents, sizing agents, defoamers and fillers.

When the stickies are deposited on the forming wire, it will block the mesh, which will make the water filtering difficult, and increase the shutdown cleaning time. If it is deposited on the press felt and the pressure roller, it will shorten the service life of the felt and affect the paper filter water; If the stickies adhere to the surface of the dryer, it will cause the paper to break or form paper holes and paper holes. If the stickies remain on the paper, it will form stains and increase the paper disease; if the stickies gather in the white water In the middle, it becomes "anionic garbage", which affects the use effect of cationic additives and hinders the recycling of white water.

Therefore, the pulp and paper industry applies various methods to control the adverse effects of stickies. These methods mainly include mechanical and chemical methods, as well as biochemical methods. Wherein, the mechanical method is to separate the glue particles from the papermaking slurry by using a process such as sieving, slag removal, washing, flotation, etc.; or to use a process such as hydrazine or dispersion to reduce the particle size of the stickies particles, thereby Reduce the harmfulness of stickies. The chemical method is to add a chemical agent with different functions such as a dispersing agent, a fixing agent, a debonding agent and an adsorbing agent in the papermaking slurry to reduce the harm of the adhesive substance; or directly apply the cleaning agent or the cleaning agent to the pulping. Surfaces of papermaking equipment, such as forming fabrics, press felts, dryers and dryers, etc., to remove deposits deposited on the surface of such equipment, or to prevent deposits from depositing on the surface of such equipment. Biochemical methods use bioenzymes to replace chemicals to degrade or passivate certain major components of the stickies, thereby impairing the hazard of stickies. For example, fat hydrolyzing enzyme can degrade fatty acid ester in the stickies, polyester hydrolase can hydrolyze polyvinyl acetate in the stickies, and amidase can hydrolyze polyamide hot melt in the stickies. .

Adhesives in pulp and paper systems can be divided into two broad categories according to their particle size: macrostickies of size >0.10mm or >0.15mm, and microstickies smaller than this size. (microstickies) o According to the way the glue is formed, it can be divided into primary stickles and secondary stickies. Primary stickies are those that come directly from the raw materials of pulp and paper; while secondary stickies are dispersed or dissolved stickies re-aggregate or with other components in the papermaking slurry ( It is formed by a combination of a sizing agent, a reinforcing agent, a retention aid filter, and a papermaking aid such as an antifoaming agent. In general, large stickies can be removed by sieving and slag removal. In addition to the removal of a part of the fine stickies by washing, it is often necessary to use chemical or biochemical methods to control their hazards.

In order to effectively control the hazards of glue in the pulp and paper process, it is often necessary to collect the stickies from the pulp and paper system, analyze their physical characteristics and chemical composition, and evaluate the degree of contamination of the pulp. Glue The material handling plan provides the basis. With regard to the method of collecting stickies from pulp, the most common method at present is to separate the stickies particles and fibers in the pulp using a mechanical sieve. For example, the American Pulp and Paper Association (TAPPI)'s method for analyzing "great stickies" in pulp, T277 om-07 (Macro stickies content in pulp: the "pick-up" method), International Association of Deinking Industries (International Association) Of Deinking Industry) Ingede Method 4 (Analysis of Macrostickies in Pulps), and International Standard 15360-2 (Recycled Pulp-Estimation of Stickies and Plastics-Part 2: Image Analysis Method), stipulates that the sieve is 0.1 mm. Or a 0.15mm slotted screen to separate the "great stickies" in the pulp. However, this method is limited to the detection of large stickies of particles having a large particle size of more than 0.1 mm or 0.15 mm, and the micro-adhesive particles having a particle size smaller than the parameters are not within the measurement range of this method. In addition, the method uses a mechanical sieve device to separate the adhesive particles in the papermaking slurry, which is inefficient and cumbersome, and is not suitable for carrying.

U.S. Patent No. 9,280,726 teaches a paper/whitewater large stick in-line analyzer and method. According to this method, a large class of glue particles in paper/white water is first separated by a slurry classifier, and then the stickies particle suspension is placed in water, and an image of the stickies particles suspended in the water is photographed with a camera. Finally, computer software was used to analyze the amount and total amount of stickies in the image. This method is also limited to the determination of large stickies, but not to fine stickies. Moreover, this method also uses mechanical means to separate the stickies of the binder in the papermaking slurry, which has the disadvantage of being cumbersome and expensive.

U.S. Patent No. 8,160,305 teaches a method and apparatus for measuring particulate contaminants in pulp and paper pulp. According to this method, first, after inserting a piece of substrate into the papermaking slurry for a certain period of time, the substrate is taken out, an image system is used to capture an image of the particle contaminant deposited on the substrate, and then the particles in the image are counted and measured, and finally An inhibitor is added to the slurry to treat the contaminants. The imaging system used in this method includes an optical scanner, a digital or film camera, or a digital or film camera for use with a reflective microscope. However, this method does not involve how to distinguish between different colored contaminant particles in the papermaking slurry. Moreover, this method has an obvious drawback: the use of "insertion" means that the substrate is suspended in the pulp, and the matrix is difficult to withstand the large shear forces generated by the flow of the pulp. For example, according to the description of this patent, the substrate is the middle portion of the sampling chamber inserted. In order to reduce the impact on the substrate during the flow of the slurry, the substrate has to be oriented parallel to the flow direction of the slurry in the sample chamber. This orientation is not conducive to sufficient contact of the substrate with the slurry, affecting the efficiency of the matrix to capture the stickies.

U.S. Patent No. 7,842,165 (China Patent No. CN101802605B) describes a quartz crystal microbalance (QCM) for determining the deposition rate of stickies in the paper industry. According to this method, the sensitivity of the sensor-induced stickies can be improved by using a non-swelling epoxy resin or a silicon-containing polymer as the surface coating of the sensor.

However, in general, all the methods of measuring stickies, to date, have some serious drawbacks, for example, or the equipment used is too bulky or too expensive, or The analysis process is too cumbersome or time consuming, or the analysis results lack sufficient accuracy and precision. For these reasons, it is difficult to use these methods as routine testing methods to monitor changes in stickies in pulp and paper systems. Also, in the existing methods, almost no method involves the analysis and identification of individual stickies particles. In addition, few people have noticed the value of preserving stickies as physical archives.

Therefore, it is very necessary to invent a high efficiency, economical and easy to use device and method to capture the pulp and paper system. Glue particles are provided to provide samples for routine monitoring of the system's stickies. Moreover, if desired, the stickies collected by such means and methods can be used to provide samples for the analysis and identification of individual stickies, or to provide physical data for easy storage and storage of records for the pulp and paper process. . Summary of the invention

Based on this, it is necessary to provide a device and a method for capturing glue in a pulp and paper system according to the above problems, and the device and the method can better capture large glue and fine glue in the pulp and paper system. Various stickies such as stickies are used for extensive monitoring purposes.

A glue capture device for a pulp and paper system, comprising

a reaction vessel comprising a containment chamber for containing a papermaking slurry;

The adsorption test piece has an adsorption surface for adsorbing particulate adhesive in the papermaking slurry flowing through the adsorption test piece, and the adsorption surface of the adsorption test piece is located in the accommodation cavity.

The above-mentioned sticking device for the glue in the pulp and paper system removes the granular stickies from the slurry of the pulp and paper system by adsorption. By using an adsorption method to capture the particulate stickies in the paper pulp sample, a series of troubles caused by the use of mechanical separation or chemical extraction can be avoided. For example, mechanical separation requires the use of bulky separation screens, which is time consuming and labor intensive; chemical extraction often requires the use of flammable and/or volatile organic solvents, and the procedures are rather cumbersome, resulting in a lack of representativeness. .

Moreover, the use of the above-mentioned glue-carrying device in the pulp and paper system provides support for the adsorption test piece by the reaction vessel, can withstand the impact of the paper slurry flow from all directions, and can accelerate the granular adhesive in the paper pulp slurry. The adsorption process shortens the adsorption reaction time, significantly improves the capture efficiency of the granular adhesive, and also improves the reproducibility of the experimental results.

In one embodiment, the adsorption test piece is a transparent adsorption test piece that allows visible light to pass through.

The inventors have recognized in research that the stickies in the papermaking slurry are often not a single color but are colorful. These different colored particulate stickies are often caused by their different origins and properties. If a single background is used to obtain an image of a granular stickies, that portion of the granular stickies similar to the background color may be lost. For example, if you only use a black background to scan a grainy stick image, black or dark particles may not be visible; conversely, if you only use a white background to scan a granular stick, white or shallow Particles of color may be lost.

Therefore, based on the above research, the above device uses a transparent adsorption test piece to adsorb the granular adhesive in the papermaking slurry, and then obtains an image of the transparent adsorption test piece under at least two preset background color conditions. It can improve the accuracy and sensitivity of monitoring glue. Both the light-colored and dark-colored granular stickies can be included by scanning the image of the granular stickies with a black and white background, respectively. Therefore, the above method can measure various stickies in a pulp and paper system by obtaining an image of a granular adhesive in different color backgrounds, and has the advantage of good monitoring effect.

In one embodiment, the adsorption test piece is in the form of a film or a sheet, and the adsorption test piece comprises a support layer and an adsorption layer coated on the surface of the support layer. Adsorption specimens in film or sheet form for easy image acquisition in different color backgrounds. In one embodiment, the material of the support layer is selected from the group consisting of: the support layer is selected from the group consisting of: a colorless transparent polymethyl methacrylate layer, a polycarbonate layer, and a polyethylene terephthalate layer. At least one of a polystyrene layer, a polyvinyl chloride layer, a polypropylene layer and a polyethylene layer, the adsorption layer being selected from the group consisting of: a polyacrylate layer, a styrene-butadiene latex layer, a polyvinyl acetate layer, and a polybutylene An olefin layer, a polyisoprene layer, an ethylene vinyl acetate layer, an epoxy acrylate layer, a styrene acrylic layer, a polyvinyl alcohol layer, a natural rubber layer, a resin acid layer, a fatty acid ester layer, a terpene resin layer, At least one of an animal wax layer, a vegetable wax layer, and a paraffin layer.

The support layer made of the above transparent polymer material has the characteristics of good light transmittance and high mechanicality. The above adsorbed layer has a special affinity for the stickies in the papermaking slurry, and can rapidly adsorb the particulate stickies from the slurry.

In one embodiment, if the pulp and paper system is based on recycled corrugated box paper (ie, OCC), the adsorption layer is selected from the group consisting of: a polyacrylate layer, a polyvinyl acetate layer, and an ethylene acetate. At least one of the vinyl ester layers;

Wherein the pulping and papermaking system is based on recycled magazine paper, the adsorption layer is selected from the group consisting of: a styrene butadiene latex layer, a polyvinyl acetate layer, and an ethylene vinyl acetate layer;

If the pulping and papermaking system is based on mixed recycled office waste paper and/or newspapers, the adsorption layer is selected from at least one of an epoxy acrylate layer, a styrene acrylic layer, and a polyacrylate layer. Species

If the pulping and papermaking system is based on chemical pulp, mechanical pulp and/or chemical mechanical pulp, the adsorption layer is selected from at least one of a resin acid layer, a fatty acid ester layer, and a terpene resin layer. Kind.

The adsorption of the adsorbent specimen to the granular stickies depends mainly on the chemical composition of the stickies and the adsorbent layer. According to the principle of similar compatibility, if the stickies and the adsorbent layer have similar chemical compositions, or their chemical compositions have similar properties, then the adsorption test piece has a strong adsorption force on the granular stickies. Therefore, according to the above arrangement, the adsorbent layer material having a good adsorption capacity with the particulate stickies to be monitored in the pulp and paper system is selected, and has a good adsorption effect.

In one embodiment, the sorbent test piece is fixed to the bottom of the accommodating cavity, and the sorbent test piece faces the inner cavity of the accommodating cavity with an absorbing surface. The adsorbent test piece is fixed to the bottom of the accommodating cavity so that the absorbing test piece has sufficient support to withstand the impact of the slurry flow from all directions. The adsorption test piece is directed toward the inner cavity of the accommodating cavity with the adsorption surface, and the adsorption reaction of the adsorption test piece and the papermaking slurry can be further promoted.

In one embodiment, the reaction vessel further includes an inlet tube and a liquid outlet tube, and the receiving chamber is a sealed receiving chamber having a liquid inlet and a liquid outlet, and the liquid inlet tube The liquid inlet is connected to the liquid outlet, the liquid inlet is disposed at an upper portion of the receiving cavity, and the liquid outlet is disposed at a side wall of the receiving cavity ; or

The reaction vessel also includes an agitator for maintaining the flow of the papermaking slurry within the containment chamber.

The in-line adsorption reaction can be carried out by using a reaction vessel having an inlet pipe and an outlet pipe, that is, a branch of the paper pulp slurry is taken out from a predetermined sampling point, introduced into the reaction vessel from the inlet pipe, and the paper pulp slurry is maintained to pass the adsorption test. The surface of the part is subjected to an adsorption reaction, and then the paper pulp slurry is discharged from the liquid discharge pipe.

The off-line adsorption reaction can be carried out by using a reaction vessel including a stirrer, that is, a paper pulp slurry of a predetermined sampling point is taken, placed in the above reaction vessel, and the paper pulp slurry in the reaction vessel is kept in a flowing state and adsorbed by mechanical stirring. The test piece reacted. In one embodiment, the receiving cavity comprises a cylindrical barrel, a sample holder and a base, the base is detachably mounted on the bottom of the barrel, and the sample holder passes through the base clamp Tightly fixed between the barrel and the base, the sample holder is provided with an adsorption mounting area for fixing the adsorption test piece. Through the above arrangement, the test piece frame is provided with the support for the impact of the paper pulp slurry, and the detachable installation of the base and the cylinder body can conveniently fix the test piece frame in the accommodating cavity body, thereby adsorbing The test piece is mounted in the receiving cavity.

In one embodiment, the solvent for accommodating the cavity is 20 ml to 20,000 ml; and the surface area of the adsorption test piece where the adsorption reaction can occur is 0.25 cm ² -600 cm ² .

The invention also discloses a method for capturing stickies in a pulp and paper system, comprising the following steps:

The papermaking slurry of the predetermined sampling point in the pulping and papermaking system is passed through an adsorption test piece capable of adsorbing the granular adhesive substance on the surface, and the adsorption test piece reacts with the adsorption test piece to adsorb the granular adhesive substance in the papermaking slurry. The surface of the test piece is adsorbed.

In one of the embodiments, the papermaking slurry is allowed to flow toward the adsorbent specimen at an angle of 45 to 90 degrees from the surface of the adsorbent test piece. The inventors have found that, in the conventional art, in order to reduce the impact of the flow of the papermaking slurry on the sampling device, the sampling device has to be oriented parallel to the flow direction of the papermaking slurry, but this orientation is not conducive to sufficient contact between the papermaking slurry and the sampling device. , affecting the capture efficiency of the sampling equipment to the glue. When the papermaking slurry and the surface of the adsorption test piece flow to the adsorption test piece at a certain angle, the papermaking slurry can be fully contacted with the adsorption test piece, thereby accelerating the adsorption process of the granular adhesive on the surface of the adsorption test piece. .

In one embodiment, the adsorption reaction comprises an off-line reaction and an on-line reaction,

The off-line reaction is: taking a paper slurry of a predetermined sampling point, placing it in a reaction vessel pre-installed with the adsorption test piece, and maintaining the papermaking slurry in the reaction vessel by mechanical stirring, shaking, rotating, and/or flipping. Reacting with the adsorbent test piece in a flowing state;

The on-line reaction is: taking a branch of the paper pulp slurry from a predetermined sampling point, and maintaining the papermaking slurry flowing through the surface of the adsorbent test piece to cause an adsorption reaction.

Different methods can be selected for sampling according to the needs of practical applications.

In one embodiment, the adsorption reaction takes 5 seconds to 4 hours; the adsorption reaction temperature is

1 ° C -99 ° C _; the adsorption reaction in the solid dry weight percentage, the paper pulp concentration of 0.05% - 15%. By adopting the above conditions, the adsorption reaction effect is better, and the adsorption of the granular adhesive can be promoted to adsorb the surface of the test piece.

Compared with the prior art, the present invention has the following beneficial effects:

The invention discloses a glue collecting device in a pulp and paper making system, and the adsorption method separates the granular adhesive from the slurry of the pulping and paper making system, and has the advantages of simple operation, accurate and reliable result. Moreover, the reaction vessel is provided as a support for the adsorption test piece, can withstand the impact of the paper slurry flow from all directions, can accelerate the adsorption process of the granular adhesive in the paper pulp, shorten the adsorption reaction time, and significantly improve the granularity. The capture efficiency of the stickies also improves the reproducibility of the experimental results.

Moreover, the device can also use a transparent adsorption test piece to adsorb the granular adhesive in the papermaking slurry, and then obtain an image of the transparent adsorption test piece under at least two preset background colors, and the monitoring glue can be improved. The accuracy and sensitivity of the stickies. Both the light-colored and dark-colored granular stickies can be included by scanning the image of the granular stickies with a black and white background, respectively. Therefore, the above method is obtained by obtaining granular adhesives in different colors. The image under the color background can measure various stickies in the pulp and paper system, and has the advantage of good monitoring effect. DRAWINGS

1 is a schematic structural view of a capture device for off-line reaction in the present invention;

2 is a schematic structural view of a capture device for an online reaction in the present invention;

3 is a schematic structural view of a detachable capture device of the base of the present invention;

4 is a schematic structural view of an image capture device according to the present invention;

Figure 5 is a schematic structural view of a flat type background platform according to the present invention;

6 is a schematic structural view of a disc type background platform according to the present invention;

Figure 7 is a schematic structural view of a conveyor belt type background platform according to the present invention;

Fig. 8 is a view showing the image of a granular adhesive on the adsorbent test piece in Example 3.

Wherein: 110. housing cavity; 111. cylinder; 112. base; 120. inlet tube; 130. outlet tube; 140. agitator; 150. specimen holder; 151. upper base plate; 152. lower base 160; sealing ring; 200. adsorption test piece; 310. image collector; 320. background platform; 321. background plate; 322. background turntable; 323. rotating shaft; 324. rotating roll; 325. background band; Background surface; 330. Light source; 410. Light-colored granular stickies; 420. Dark-granular stickies. detailed description

In order to facilitate the understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the understanding of the present disclosure will be more fully understood.

It should be noted that when an element is referred to as being "fixed" to another element, it may be directly on the other element or the element may be present. When an element is considered to be "connected" to another element, it can be directly connected to the other element.

All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to the invention. The terminology used in the description of the present invention is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

A device for capturing stickies in a pulp and paper system, comprising a reaction vessel and an adsorption test piece.

The reaction vessel includes a receiving cavity for containing a papermaking slurry;

The adsorption test piece is fixed in the accommodating cavity for adsorbing a granular adhesive substance flowing through the papermaking slurry of the adsorption test piece, and an adsorption surface of the adsorption test piece is located in the accommodating cavity.

Pulping processes suitable for use in the present invention include, but are not limited to, various chemical pulps, various mechanical pulps and chemical mechanical pulps, and various waste paper recycled pulps. Papermaking processes suitable for use in the present invention include, but are not limited to, packaging paper, boxboard, corrugated base paper, household paper, newsprint, uncoated printed writing paper, coated printing paper, white paperboard, and various specialty papers and paperboards. .

The inventors have noted in the study that the stickies in the papermaking slurry are often not a single color but a colorful For example, including red, blue, yellow, green, black or dark, white or light, and so on. These different colored particulate stickies are often caused by their different origins and properties. If only a single background is used to obtain an image of the granular stickies, some of the particulate stickies similar to the background color may be lost. For example, if you only use a black background to scan a grainy stick image, black or dark particles may not be visible; conversely, if you only use a white background to scan a granular stick, white or shallow Particles of color may be lost.

Therefore, based on the above research, preferably, the adsorption test piece is a transparent film that allows visible light to pass through. The transparent adsorption test piece is used to adsorb the granular adhesive in the paper pulp, and then the image of the transparent adsorption test piece under the condition of at least two preset background colors can be obtained, which can improve the precision and sensitivity of the glue. . Both the light-colored and dark-colored granular stickies can be included by scanning the image of the granular stickies with a black and white background, respectively. Therefore, the method of the present invention can determine various stickies in a pulp and paper system by obtaining images of granular adhesives in different color backgrounds, and has the advantage of good monitoring effect.

The glue sticking device and method in the pulp and paper making system of the invention is suitable for capturing various color granular adhesives, such as red, blue, yellow, green, black or dark colors. , white or light colors, etc. Also, the size of the suitable granular adhesive includes fine particle-shaped stickies having a particle size of less than 0.15 mm or 0.1 mm, and large-grained stickies having a particle size of more than 0.1 mm or 0.15 mm.

Since the glue in the pulp and paper system has no fixed chemical composition, its chemical composition varies greatly depending on the papermaking raw materials and the production process, but the method of the present invention is also suitable for capturing most pulp and paper processes. Granular stickies encountered. Sources of these stickies include, but are not limited to, the following: pressure sensitive adhesives, hot melt adhesives, various natural and synthetic adhesives, coating adhesives, residual inks, natural resins, defoamers for papermaking, sizing Agents, or enhancers, and mixtures of these materials with fine fibers and/or inorganic particles. The inorganic particles further include: kaolin, talc, bentonite, calcium carbonate, titanium dioxide, or a synthetic silicate.

The above predetermined sampling points are selected from several sampling points in different parts of the system according to the purpose and requirements of the capture and the process flow characteristics of the pulp and paper system. The pulp and paper system described herein includes various stages from the pulping stage to the sheet drying section. Some system pulping sections are separate from the papermaking section, and some are joined together and are suitable for use in the method of the invention.

The above sampling points include, but are not limited to, the following parts of the pulp and paper system: pulper outlet, high concentration and low concentration cleaner, coarse sieve and fine sieve machine, fiber grading sieve, pulp concentrator, refiner, heat dispersion Machine, bleaching tower, flotation deinking equipment, air flotation tank, discharge tower, slurry storage tower, slurry pool, slurry tank, pressure screen, forming wire, headbox. The slurry of the present invention includes, but is not limited to, a feed port, a discharge port, a slag discharge port, and/or a papermaking slurry inside the sampling points taken from these sampling points, slurry, filtrate, white water, etc. .

The determination of a specific sampling point depends first on the purpose and requirements of capturing the stickies. Some capture missions are designed to monitor the distribution of stickies throughout the pulp and paper system, either to monitor the efficiency of a pulp and paper stage or the removal rate of stickies. For the former, the sampling points are distributed throughout the main parts of the system, while the latter only needs to determine a small number of sampling points around the part to be monitored.

The determination of the sampling point is also dependent on the process flow of the pulp and paper. The process flow of different pulp and paper systems is quite different. For example, the same is the OCC papermaking system, and some from the pulper to the headbox, including many stages, such as Fiber grading sieves, multi-stage fine screening, slag removal, thickeners, refiners, heat dispersion, etc., some only undergo simple slag removal and coarse screening. Obviously, if you want to monitor the distribution of the entire system's stickies, the former has more sampling points than the latter.

When the capture method of the present invention is used to capture a granular stick in a pulp and paper system, after the sampling point is determined, the next step is to adsorb the granular glue in the slurry of each sampling point by adsorption. The matter is separated.

In order to achieve the purpose of adsorbing the granular adhesive, the adsorbent test piece only needs to have a surface capable of adsorbing the granular adhesive, and its shape and size can be designed according to specific requirements. However, in view of convenience and feasibility in practice, it is preferable that the adsorption test piece is in the form of a film or a sheet, and the adsorption test piece comprises a support layer and an adsorption layer coated on the surface of the support layer. More preferably, the support layer is selected from the group consisting of: a colorless transparent polymethyl methacrylate (PMMA) layer, a polycarbonate (PC) layer, a polyethylene terephthalate (PET) layer, polyphenylene. At least one of a vinyl layer (PS) layer, a polyvinyl chloride (PVC) layer, a polypropylene (PP) layer, and a polyethylene (PE) layer, the adsorption layer being selected from the group consisting of: a polyacrylate (PA) layer, and a layer Benzene latex (SBR) layer, polyvinyl acetate (PVAc) layer, polybutadiene (PBD) layer, polyisoprene (PIP) layer, ethylene vinyl acetate (EVA) layer, epoxy acrylate (EA) a layer, a styrene acrylic acid (PSAA) layer, a polyvinyl alcohol (PVA) layer, a natural rubber layer, a resin acid layer, a fatty acid ester layer, a terpene resin layer, an animal wax layer, a vegetable wax layer, and a paraffin layer At least one.

The support layer made of the above transparent polymer material has the characteristics of good light transmittance and high mechanical strength. The above adsorbing layer has a special affinity for the stickies in the papermaking slurry, and can rapidly adsorb the particulate stickies from the slurry.

The above-mentioned adsorption test piece including the support layer and the adsorption layer can be prepared by various methods, and when the adsorption layer material is applied to the support layer, a solvent coating, a latex coating, or a hot melt adhesive coating method can be employed. Among them, the solvent coating method dissolves the material of the adsorption layer in an organic solvent, and then uniformly applies the resulting solution to the surface of the support layer. After the solvent was volatilized, it was further cut into the required size to form an adsorption test piece. In the latex coating method, the adsorbent layer material is emulsified in water, and the obtained emulsion is applied to the surface of the support layer, and after drying, the adsorbent test piece can be formed. The hot melt coating method heats the material of the adsorption layer to a liquid having a certain fluidity without the participation of water or an organic solvent, and then applies the molten liquid to the surface of the support layer, and then cools. , to solidify the coating. A suitable adsorption layer thickness may be selected between 1 μηι and 100 μηι, and a more suitable adsorption layer thickness is between 5 μηι and 50 μηι.

In accordance with the requirements of the present invention, the absorbent test pieces can often be replaced by various tape or film products available on the market. This is because most of these products have the essential features of the absorbent test pieces described in the present invention. These features include a suitable support layer and adsorption layer. The support layer (ie support medium) of many of these products is made of colorless and transparent polymer material, the thickness is usually between 0.05mm and 0.5mm, the width is from several millimeters to more than one meter, and the length can be up to several. Ten meters, even hundreds of meters. Moreover, the adsorption layer (i.e., the viscous coating) of these products often contains the components required for the adsorption layer of the present invention. Suitable products include, but are not limited to: BOPP tape, PE tape, PET tape, OPP tape, PVC tape, etc.

In general, the adsorption of the adsorbent specimen to the particulate stickies depends mainly on the chemical composition of the stickies and the adsorbent layer. According to the principle of similar compatibility, if the stickies and the adsorbent layer have similar chemical compositions, or their chemical compositions have similar properties, then the adsorption test piece has a strong adsorption force on the granular stickies.

Therefore, preferably, if the pulp and paper making system is based on recycled corrugated box paper (ie, OCC), the adsorption layer is selected from the group consisting of: a polyacrylate layer, a polyvinyl acetate layer, and ethylene vinyl acetate. At least one of the layers; Wherein the pulping and papermaking system is based on recycled magazine paper, the adsorption layer is selected from the group consisting of: a styrene butadiene latex layer, a polyvinyl acetate layer, and an ethylene vinyl acetate layer;

According to the above arrangement, the adsorption layer material having good adsorption capacity with the granular adhesive to be captured in the pulp and paper system is selected, and has a good adsorption effect.

It can be understood that in the sampling step, only the paper pulp slurry needs to flow through the surface of the adsorption test piece, so that the granular glue can be adsorbed, whereas in the conventional technology, the sampling device is usually used to reduce the flow of the paper pulp. For impact, the sampling device has to be oriented parallel to the flow of the papermaking slurry. However, this orientation is not conducive to sufficient contact between the papermaking slurry and the sampling equipment, affecting the capture efficiency of the sampling equipment for the glue. Preferably, the paper pulp slurry is flowed to the adsorption test piece at an angle of 45-90 degrees to the surface of the adsorption test piece, so that the paper pulp slurry can be sufficiently contacted with the adsorption test piece, thereby accelerating the granular adhesive material in the adsorption test. The adsorption process on the surface of the piece.

For the sampling method, it can be set according to the purpose and requirements of the capture. It is only necessary to make a sufficient amount of the papermaking slurry flow through the adsorption test piece to make the sampling representative.

For example, a sticker trapping device including a reaction vessel and a sorbent test piece including a accommodating cavity for accommodating a papermaking slurry, and a absorbing surface of the absorbing test piece may be employed Said to accommodate the cavity. It will be appreciated that when using the glue capture device, some necessary peripheral aids are required; these include, but are not limited to: necessary piping, pipe connections, pipe valves, fluid pumps, flow meters, mechanical mixing equipment or Shake the device and more.

With the stick catching device, the sticking efficiency of the stickies can be improved, and the trapping device has a simple structure, a low cost, and is easy to operate. Thus, multiple such capture devices can be used simultaneously to capture the stickies in the paper pulp slurry of a plurality of paper sampling points in a pulp and paper system, thereby reducing the cost of daily monitoring of the stickiness distribution of the pulp and paper system. Operational difficulty.

For the volume of the receiving chamber containing the papermaking slurry, it can be understood that, if an off-line reaction is adopted, a larger receiving cavity is required to ensure the representativeness of the sampling, such as the method of online reaction, which is relatively small. The chamber can be accommodated to meet the demand. In the present invention, the volume of the accommodating cavity is selected from the range of 20 ml to 20,000 ml, and the suitable volume of the accommodating cavity is selected from the range of 50 ml to 5000 ml, and a more suitable accommodating cavity volume is selected from 100 ml to 2000 ml. Between the ranges. And the shape of the receiving cavity is selected from the group consisting of a cylindrical shape, an elliptical cylindrical shape, a square cylindrical shape, a rectangular prism shape, or any suitable geometric shape, and a suitable receiving cavity shape is selected from a cylindrical shape or a square cylindrical shape. The material from which the receiving cavity is made is selected from the group consisting of metal, glass and/or plastic, and a suitable reaction vessel material is selected from plastics.

It can be understood that the adsorption test piece used in the present invention can be installed at any position in the accommodating cavity, and as long as the adsorption test piece has sufficient support, it can withstand the impact of the slurry flow from various directions to ensure the adsorption of the adsorption test piece during the adsorption reaction. The surface energy can be sufficiently in contact with the papermaking slurry, but a suitable position is to mount the adsorption test piece at the bottom of the accommodating cavity, parallel to the bottom of the accommodating cavity, and to face the absorbing surface facing the inside of the accommodating cavity, such that It can be ensured that the paper pulp slurry is in sufficient contact with the adsorption layer of the adsorption test piece during the adsorption reaction, and the adsorption efficiency of the stickies is improved. From a practical point of view, the sorbent test piece can be mounted directly below an opening in the bottom of the accommodating cavity. The shape of the opening is substantially the same as that of the adsorbent test piece, but the size is slightly smaller. In order to increase the mechanical endurance of the adsorbent test piece, a support plate may be added under the adsorbent test piece. Another method of installing the sorbent test piece is to first fix the sorbent test piece in a frame and then mount the frame with the sorbent test piece at the bottom of the accommodating cavity. The shape of the frame used to fix the adsorption test piece is roughly the same as that of the adsorption test piece, and the outer size is slightly larger than that of the adsorption test piece, but the middle opening is slightly smaller than the adsorption test piece. The preferred frame should have two upper and lower pieces. This allows the absorbent test piece to be sandwiched between the two frames.

In order to make stickies particulate adsorption test piece having a sufficient adsorption reaction zone, the area of the adsorption test piece used in the present invention is in the range of 0.25 cm ^² -600cm ^2, more suitable adsorbent selected area of the specimen Between the range of 2 cm ² to 100 cm ^2d , a more suitable adsorption test piece area is selected from the range of 5 cm ² to 50 cm ² . The shape of the adsorbent test piece may be selected from a square, a rectangle, a circle, an ellipse, or any suitable geometric shape.

For sampling scenarios, including offline reactions and/or online reactions,

The off-line reaction is: taking a paper pulp slurry of a predetermined sampling point, placing it in a reaction vessel pre-installed with the adsorption test piece, and maintaining the papermaking slurry in the reaction vessel in a flowing state to react with the adsorption test piece. For example, the paper slurry can be maintained in a mechanically agitated, shaken, rotated, and/or inverted manner.

When sampling in an off-line reaction, it may be sampled using the glue capture device shown in FIG. 1, the capture device including a reaction vessel and a sorption test piece, the reaction vessel including a accommodating cavity 110 for accommodating a papermaking slurry, the adsorption test The adsorption surface of the piece 200 is located within the receiving cavity 110. The reaction vessel should also include an agitator 140 for maintaining the flow of papermaking slurry within the containment chamber 110. Specifically, the accommodating cavity 110 of the reaction vessel is a cylinder with two ends open. The bottom of the accommodating cavity 110 is composed of two upper and lower base plates. The upper base plate 151 is connected to the bottom of the receiving cavity, and the upper base plate 151 has an opening in the middle thereof. The opening of the upper base plate 151 may be circular, square, rectangular, or other shape; the area may be equal to or smaller than the reaction container. The internal cross-sectional area. The lower base plate 152 is fixed to the lower side of the upper base plate 151 by a fixing screw or the like. The adsorption test piece 200 is sandwiched between the upper and lower base plates, and its adsorption layer faces the inside of the reaction vessel. A paddle agitator 140 is disposed above the adsorption test piece 200, and the agitator shaft is perpendicular to the surface of the adsorption test piece. During the adsorption reaction, due to the chemical attraction of the adsorption layer and the mechanical driving force generated by the stirring action, the adsorption of the granular adhesive in the slurry on the surface of the adsorbent specimen is accelerated and enhanced, thereby increasing the capture granularity. The efficiency of the stickies.

When sampling in the online reaction, it can be sampled by the glue trapping device shown in FIG. 2, the capturing device comprising a reaction vessel and a absorbing test piece, the reaction vessel comprising a accommodating cavity 110 for accommodating the papermaking slurry, the absorbing test The adsorption surface of the piece 200 is located within the receiving cavity 110. The reaction container further includes an inlet pipe 120 and a liquid outlet pipe 130. The accommodating cavity 110 is a closed accommodating cavity, and is provided with a liquid inlet port and a liquid outlet port, and the liquid inlet pipe 120 and the inlet pipe 120 The liquid outlet is connected to the liquid outlet, and the liquid inlet is disposed at an upper portion of the receiving cavity 110, such as a top or a sidewall, and the liquid outlet is disposed at the The side wall of the cavity 110 is received. The bottom structure of the reaction vessel is substantially the same as that shown in Figure 1. During the adsorption reaction, a branch slurry is taken from the pulping and papermaking system and flows into the adsorption reaction vessel through the feed port, and flows out from the discharge port after coming into contact with the adsorption layer. Due to the dual action of the chemical attraction of the adsorption layer and the mechanical driving force generated by the slurry flow, the granular adhesive in the slurry is accelerated and strengthened in the adsorption test piece table. The adsorption of the surface thus increases the efficiency of capturing particulate stickies.

In order to facilitate the installation of the adsorption test piece, the bottom of the adsorption reaction vessel may be open or have an opening, and a removable base is attached. For example, the accommodating cavity includes a cylindrical barrel, a sample holder and a base, the base is detachably mounted on the bottom of the cylinder, and the specimen holder is clamped and fixed to the Between the cylinder and the base, the sample holder is provided with an adsorption mounting area for fixing the adsorption test piece. Specifically, as shown in Fig. 3, the accommodating cavity of the device is mainly composed of a cylindrical cylinder 111 and a disk-shaped base 112. In use, the adsorbent test piece 200 is first mounted on a circular test piece holder 150, and then the test piece holder 150 is mounted on the base 112 of the receiving cavity, and then the sealing ring 160 is attached, and finally the threaded connection is The cylinder 111 is mounted on the base 112. The circular specimen holder 150 has the same area and shape as the outer cross section of the cylinder 111, but has an opening in the middle. The shape of the opening may be circular, square, rectangular, or other shape; its area is slightly smaller than the absorbent test piece so that the absorbent test piece can cover the entire opening.

It can be understood that the adsorption reaction of the glue with the adsorption test piece requires a certain reaction time, and the reaction time of the suitable adsorption reaction is selected from 5 seconds to 4 hours, and the suitable adsorption reaction time is selected from 10 seconds to 20 minutes. Between the ranges, a more suitable adsorption reaction time is selected from the range of 20 seconds to 10 minutes. The length of time required for the adsorption reaction depends mainly on the concentration of the slurry and the temperature of the adsorption reaction. The concentration of the slurry referred to herein means the percentage of the dry weight of the solid in the slurry. The concentration of the pulp or the concentration of the slurry described in the present invention means the percentage of the dry weight of the solid in the slurry.

The suitable paper pulp concentration ranges from 0.05% to 10%, and the suitable slurry concentration ranges from 0.2% to 5%. The more suitable slurry concentration range is between 0.5% and 4%. When the concentration of the slurry is too low, the adsorption rate of the granular stickies is slow, which affects the adsorption efficiency. Conversely, if the concentration of the slurry is too high, the fluidity of the slurry in the reaction vessel is poor, which is not conducive to the adsorption of granular stickies. .

The suitable adsorption reaction temperature ranges from 1 °C to 99 °C, and the suitable reaction temperature range is between 10 °C and 60 °C. The more suitable reaction temperature range is between 20 °C and 50 °C. . Too high or too low a temperature of the papermaking slurry is detrimental to the adsorption of the particulate stickies on the surface of the adsorbent specimen.

After the end of the adsorption reaction, the adsorbent sample to which the particulate adherend is adsorbed is subjected to appropriate rinsing to remove the fibers and the unrelated foreign matter adhering to the test piece, and after drying, it can be used for further use.

These further uses include, but are not limited to, image acquisition and processing techniques or gravimetric analysis of the relative amount of stickies in the slurry; observation of the morphology, color, size, etc. of the particulate stickies using an optical microscope; Corresponding chemical analysis techniques, such as micro-infrared spectroscopy and laser micro-Raman spectroscopy, to identify the chemical composition of individual granular adhesives; or, as a physical data storage process for pulp and paper production, for future recovery check.

In the present invention, the relative content of the stickies in the slurry is analyzed by image acquisition and processing techniques, specifically to obtain an image of the adsorbed test piece under at least two preset background color conditions; and further analyzed by an image processing system. And measuring the nature and quantity of granular stickies. Finally, the relative content of the particulate stickies at each sampling point is listed to obtain the distribution of the stickies in the pulp and paper system.

It will be appreciated that what is directly obtained by the process of the present invention is the stickies of the harmful portion of the papermaking slurry, rather than the total stickies. For a pulp and paper system, not all of the stickies in the system can be harmful to the papermaking process. For example, when the stickies are treated with the stickifier control agent, the chemical properties of the surface change, and thus no longer deposit on the surface of the paper machine, which is harmful to production. So, from a practical point of view, in the monitoring system The full amount of glue is not significant. Effective monitoring should focus on monitoring the harmful parts of the glue, that is, focusing on the part of the glue that poses a hazard to the paper production process. This makes sense for the control of the glue in the pulp and paper process. This is the case with the method of the invention. What is captured by the process of the invention is the portion of the harmful stickies particles in the pulp and paper system.

For the selection of the background color, it is preferable to use a complementary color complementary to the color of the granular adhesive as the background color, which can significantly improve the quality of the scanned image and improve the resolution of the scanning. Or the background color includes at least white and black. The white and black background colors have good versatility, which can highlight the light and dark granular adhesives in the image, improve the quality of the scanned image, and improve the scanning resolution.

When analyzing and processing the image of the particulate stickies, it further includes filtering the image processing results to remove the stickies that are not particulate. For example, the most common non-stick particles are fibers or fine fibers. These objects are adsorbed on the surface of the adsorbent test piece, indicating that their surfaces are more or less sticky with impurities. Therefore, these objects are sometimes considered as part of the composition of the glue. However, it is sometimes necessary to remove them from the detected particles. These fibers and fine fiber particles generally have a relatively small roundness and a relatively large particle aspect ratio due to the particulate stickies. If it is desired to remove particles from these objects, an image processing system can be applied to filter the image of the particles based on the selected parameters. The content of the granulated stickies was calculated by discarding the papermaking fibers having a circularity of less than 0.1 and/or an aspect ratio of more than 10 as judged by the image processing system.

In order to improve the simplicity of the operation, in the detecting step, the image of the adsorption test piece under the preset background color condition is preferably acquired by the image acquisition device, and the image collection device comprises an image collector and a background platform, and the image collector uses And collecting an image of the adsorption test piece, wherein the background platform is used to cooperate with the adsorption test piece, for example, the adsorption test piece is placed on a background platform, and the image acquisition device obtains an image from above the adsorption test piece, or covers the adsorption by the background platform. The test piece, and the image capture device acquires an image from under the adsorbent test piece. The background platform includes a background surface of at least two preset background colors, and at least two of the background surfaces are switchable from each other.

The image capture device further includes a light source for providing illumination to the image collector; the light source suitable for use in the image capture device of the present invention includes but is not limited to: LED (Light Emitting Diode), fluorescent lamp, halogen lamp, metal halide Lights, neon lights. The illumination of the light source can be transmissive, specular or diffuse.

The structure and working principle of the above image collecting device are shown in Fig. 4. A absorbing test piece 200 with a frame-shaped test piece holder 150 adsorbs sticky particles of different color glues from the paper pulp slurry (light-colored granular adhesive) The object 410 and the dark granular adhesive 420) are placed on a background platform 320 having black and white colors. Light emitted by the light source 330 is incident on the adsorption test piece 200, thereby causing diffuse reflection and/or specular reflection to be accepted by the image collector 310 (camera) and forming an image.

In order to reduce the difficulty of operation, it is convenient and quick to realize the conversion of different color backgrounds, and a dedicated background platform can be used. For example, the background platform can be selected from the group consisting of: a flat background platform, a disc background platform, or a conveyor belt background platform.

As shown in FIGS. 4-5, the flat background platform includes a slidable background plate, and the background plate is provided with a background 329 surface of at least two colors. The background platform has a slider (noted out) that allows the background platform to slide back and forth along the horizontal direction, changing the color of the background. When the adsorption test piece 200 fixed to the sample holder 150 is placed on the background platform, the same group of granular adhesives (light-colored granular adhesive 410 and dark granular adhesive 420) , respectively Different images with white and black backgrounds are produced.

As shown in FIG. 6, the disc-type background platform includes a background turntable 322 and a rotating shaft 323. The background turntable 322 is mounted on the rotating shaft 323 and rotatable around the rotating shaft 323. The background surface 329 of at least two colors (four in the figure); driving the background turntable by electric or mechanical means to rotate the axis to a certain angle, the color of the background can be changed, and the same group of granular glue Stickies (light granules of glue 410 and dark granules of glue 420) produce different images with different color backgrounds 329 as backgrounds, respectively.

As shown in FIG. 7, the conveyor belt background platform includes a rotating roller 324 and a background belt 325. The background belt 325 can be rotated around the rotating roller 324 by the rotating roller 324. The background belt 325 is provided with at least two. The color of the background surface 329. One of the two rotating rollers 324 is driven electrically or mechanically, and the rotating roller drives the multicolor background strip 325 a certain distance to convert the background from one color to another. Multicolor background strips can be available in black and white only, or as needed, with a wider variety of colors to make the same set of granular stickies (light granules of sticky material 410 and dark granules) The glue 420) produces different images with different color background faces 329 as backgrounds.

An image capture device suitable for use in the image capture device of the present invention is a camera selected from a black and white or color line array camera having a resolution of more than 500 pixels, or a black and white or color line array camera having a resolution of more than 200,000 pixels. A camera suitable for use in the present invention includes a CCD (Charge Coupled Device) camera and a CMOS (Complementary Metal-Oxide Semiconductor) camera.

The image of the granular adhesive obtained by the above apparatus and method can be saved as a graphic record of the pulp and paper production process or as a graphic data of the experimental results. This increases the reliability and credibility of production records and experimental results.

Preferably, the properties of the particles in the image are analyzed by an image processing system selected from the group consisting of a PC Based system, a PLC system, or an embedded system. The analysis process includes a pre-processing, an image measurement, and a classification step; the pre-processing step includes: at least one of brightness correction, color extraction, contrast conversion, edge enhancement, and binarization processing;

The image measuring steps include: particle positioning, spot determination, edge determination, area measurement, point-to-point distance measurement, point-to-edge distance measurement, edge-to-edge distance measurement, circle diameter measurement, angle measurement, roundness measurement, and length At least one of width ratio measurements;

In the classification step, classification is performed by particle size, particle roundness, and/or particle aspect ratio.

It can be understood that the papermaking fibers can be excluded by analyzing the roundness of the particles and/or the aspect ratio of the particles after the image measuring step, as needed;

The properties of the particles in the image are analyzed by the image processing system described above, including but not limited to: total number of particles, area of each particle, circle diameter of each particle, roundness of each particle, length of each particle, width of each particle, each Particle aspect ratio, total particle area, average particle area, average particle diameter, average particle length, average particle width, average roundness of particles, average aspect ratio of particles, particle size distribution, particle roundness distribution, particle length distribution , particle aspect ratio distribution, total particle area percentage, etc. Example 1

First, the experimental conditions.

1. Prepare a capture device for the glue in the pulp and paper system.

The sticking device for the glue in the pulp and paper making system of the embodiment comprises a reaction vessel, a absorbing test piece and a power agitator, the reaction vessel comprising a accommodating cavity for accommodating the papermaking slurry, the absorbing test piece being fixed at the Said to accommodate the cavity.

The accommodating cavity comprises a cylindrical barrel, a sample holder and a base, and the base is detachably mounted on the bottom of the cylinder by a screw connection, and the specimen holder is clamped and fixed by the base Between the cylinder and the base, the sample holder is provided with an adsorption mounting area for fixing the adsorption test piece.

The inner diameter of the cylinder in this embodiment is 100 mm, the height is 150 mm, and the adsorption test piece is "3M long" of about 60 mm.

Scotch Packaging Tape" (purchased from: Costco store in the United States, the support layer is polypropylene film, the adsorption layer is polyacrylate adhesive) instead, the transparent sealing tape is pasted in the middle opening area is 54mm x 40mm Below the rack, the specimen holder to which the transparent sealing tape is pasted is screwed to the bottom of the cylinder through the screw of the base and the cylinder, and the adsorption layer is facing upward toward the inner cavity of the cylinder. Then, a test piece is mounted above the adsorption test piece. A paddle stirrer (model: JB90-D, Shanghai Specimen Model Factory), a 50mm diameter four-blade slurry agitator, wherein the distance between the stirring paddle and the surface of the adsorbent test piece is about 10mm, that is, the pulping and papermaking system A capture device for medium glue.

2. Preparation of pulp.

Take the country's waste corrugated paper (OCC) and add enough tap water to grind it with PL12-00 high-concentration hydraulic pulper (Xianyang Taisite) for 10 minutes to obtain a concentration of about 13% (as a percentage of solid dry weight) Pulp; diluted with tap water to 1% concentration.

3. Adsorption test.

The sample of the paper pulp to be tested is adjusted to the desired pulp consistency. 600 g of the above papermaking slurry was placed in the above reaction vessel to which the test piece was attached. Then, the slurry in the reaction vessel was agitated at room temperature under the desired stirring speed and stirring time. After the end of the adsorption reaction, the adsorbent test piece was taken out, and the fibers attached to the test piece and the non-related matter were gently washed away with a washing bottle. After the test piece is air-dried, it is used for the next image acquisition.

4. Image acquisition and analysis.

The image acquisition device used in this implementation was modified with a Canon L1DE120 scanner. The modified part replaced the original cover of the scanner with a flat background platform. The black and white two-color background consisted of black and white plastic sheets. When collecting the glue image, insert the processed adsorption test piece into the window of the special image acquisition device, and collect the image with the parameters of the following image acquisition: The background is black and white, the color mode is black and white, and the image area is 2500x1800 pixels. The image resolution is 1200dpi. When scanning with a black background, the threshold is 40, and the resulting image is mainly white or light-colored granular adhesive; while scanning with a white background, the threshold is 128, and the resulting image is mainly black or dark granular. Stickies.

After image acquisition was completed, the number and area of particles in the image were measured using image analysis software imageJ 1.49v. Then, calculate the relative amount of stickies of the pulp according to the following formula:

Sen

C ⁼ X 1.0^ (ppm) Where: A _p is the total area of the particles in the scanned image (pixels); ^ is the scanned area of the adsorbent specimen.

Second, the experimental method

This example examines the effect of the adsorption reaction time on the adsorption efficiency when the capture device of the present invention is used to capture the stickies in the papermaking slurry.

In a series of adsorption reactions, the stirring speed was fixed at 450 rpm, but the reaction time varied from 30 seconds to 300 seconds. Third, the experimental results.

The experimental results are shown in the table below.

Table 1. Effect of adsorption reaction time on adsorption efficiency

As can be seen from the above results, the capturing device of the present invention has a relatively high efficiency, and even if only 30 seconds of stirring time, 2,100 particulate stickies have been captured from the test slurry, and the amount of the stickies is 35,800 ppm. . As the adsorption reaction time increases, the stickies captured by the adsorbent specimens also increase accordingly. Example 2

First, the experimental conditions.

Refer to Example 1.

Second, the experimental method.

This example examines the effect of agitation speed on the adsorption efficiency when the capture device of the present invention is used to capture the stickies in the papermaking slurry.

In a series of adsorption reactions, the adsorption reaction time is fixed at 120 seconds, but the stirring speed is from 150 rpm to

Between 1400 rpm.

Third, the experimental results.

The experimental results are shown in the table below.

Table 2. Effect of stirring speed on adsorption efficiency

It can be seen from the above results that the gentle rotation speed is advantageous for the adsorption test piece to capture the granular adhesive. The stirring speed is too fast and the captured glue is lowered. Example 3

First, the experimental conditions.

1. Prepare a glue capture device.

The stick catching apparatus of this embodiment includes a reaction vessel and a absorbing test piece, and the reaction vessel includes a accommodating cavity for accommodating the pulping slurry, and the absorbing test piece is fixed in the accommodating cavity.

Considering that the adsorption test piece should have a certain impact resistance against paper pulp, a pair of frame-shaped test piece holders are provided, and the outer diameter of the frame-shaped test piece frame is 70 mm x 70 mm, and the opening between them is 54 mm x 54 mm.

The adsorption test piece comprises a support layer and an adsorption layer coated on the surface of the support layer, and is made of "Ming Ting" transparent sealing tape (purchased from: Wal-mart shop, the support layer is polypropylene, and the adsorption layer is polyacrylate adhesive) Conjunction) Replacement. .

The transparent sealing tape is used as the adsorption test piece, and a transparent sealing tape with a length of about 60 mm is attached to the opening in the middle of one of the test piece holders, and then another test piece holder is mounted to make the upper and lower test pieces The middle of the rack is covered with tape, and the specimen is attached to the specimen rack.

The above-mentioned sample holder on which the adsorption test piece was mounted was mounted on the bottom of the accommodating chamber of a reaction container having a volume of 600 ml, thereby obtaining a sticker trapping device.

2. Adsorption test.

The paper slurry sample to be tested is adjusted to the desired slurry concentration and preheated to the desired temperature. 500 g of the above papermaking slurry was placed in the above-mentioned reaction vessel (i.e., a sticker trapping device) to which the adsorbent test piece was attached. Then, keep the reaction for a certain period of time by shaking. After the end of the adsorption reaction, the paper pulp slurry in the reaction vessel was removed, the adsorbent test piece was taken out, and the fibers attached to the test piece and the unrelated foreign matter were gently washed away with a wash bottle. After the test piece is air-dried, it is used for the next image acquisition.

3. Image acquisition and analysis.

Refer to Example 1.

Second, the experimental method.

In this embodiment, when the capture device of the present invention is used to capture the glue in the papermaking slurry, the transparent adsorption test piece is matched with different background colors to obtain an image of the granular adhesive under different background color conditions.

The pulp used in this example consisted of 90% old corrugated paper (OCC) and 10% shredded paper powder containing hot melt adhesive.

OCC is "Mei 12#" waste paper; shredded paper is recycled from waste paper with hot melt adhesive and pulverized by micro-pulverizer FT102 (Tianjin Taister).

The two raw materials are mixed with deionized water in a certain ratio, and then added to a PL12-00 high-concentration hydraulic pulper (Xianyang Taisite). After 15 minutes, the pulp is prepared to have a concentration of about 13%. The pulp was diluted to 4% concentration (as a percentage of solid dry weight) with deionized water. The adsorption reaction experiment was carried out by taking 500 g of 4% slurry pulp at 35 ° C for 10 minutes. The image is captured in white and black, the color mode is black and white, the image area is 2500x2400 pixels, and the image resolution is 1200dpi. The white background scan has a threshold of 40 and the black background scan has a threshold of 140.

Third, the experimental results.

The experimental results are shown in Figure 8 and the table below. As can be seen from the figure, the images captured on a black background are mainly white or light-colored granular stickies, while the images captured on a white background. It is mainly a black or dark colored granular stickies. That is, a corresponding amount of light-colored and dark-colored granular stickies are present in this slurry sample.

Table 3. Adhesive concentration

It can be further seen from the above results that the image analysis results between the two experiments have better reproducibility, whether it is an image of a white background or an image of a black background. Therefore, the method and apparatus of the present invention are used to obtain an image of the stickies in the papermaking slurry, which has relatively high reliability. The technical features of the above-described embodiments may be arbitrarily combined. For the sake of brevity of description, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be considered as the scope of this manual.

The above-described embodiments are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but is not to be construed as limiting the scope of the invention. It should be noted that a number of variations and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be determined by the appended claims.

Claims

claims

1. A device for capturing adhesives in a pulping and papermaking system, characterized by comprising:

Reaction vessel, including a holding cavity for holding papermaking slurry;

The adsorption test piece has an adsorption surface for adsorbing granular stickies in the papermaking slurry flowing through the adsorption test piece. The adsorption surface of the adsorption test piece is located in the accommodation cavity.

2. The adhesive capture device in the pulp and papermaking system according to claim 1, characterized in that the adsorption test piece is a transparent adsorption test piece that allows visible light to pass through.

3. The device for capturing adhesives in a pulping and papermaking system according to claim 2, characterized in that the adsorption test piece is in the form of a film or a sheet, and the adsorption test piece includes a support layer and a layer coated on the support. adsorption layer on the surface.

4. The adhesive capturing device in the pulping and papermaking system according to claim 3, characterized in that the material of the support layer is selected from: The support layer is selected from: Colorless and transparent polymethacrylate At least one of ester layer, polycarbonate layer, polyethylene terephthalate layer, polystyrene layer, polyvinyl chloride layer, polypropylene layer and polyethylene layer, the adsorption layer is selected from: polyethylene Acrylate layer, styrene-butadiene latex layer, polyvinyl acetate layer, polybutadiene layer, polyisoprene layer, ethylene vinyl acetate layer, epoxy acrylate layer, styrene acrylic layer, polyvinyl alcohol layer, At least one of a natural rubber layer, a resin acid layer, a fatty acid ester layer, a terpene resin layer, an animal wax layer, a plant wax layer and a paraffin wax layer.

5. The adhesive capture device in the pulping and papermaking system according to claim 4, characterized in that, if the pulping and papermaking system uses recycled corrugated box paper as the main raw material, the adsorption layer is selected from: At least one of a polyacrylate layer, a polyvinyl acetate layer, and an ethylene vinyl acetate layer;

If the pulping and papermaking system uses recycled magazine paper as the main raw material, the adsorption layer is selected from: at least one of a styrene-butadiene latex layer, a polyvinyl acetate layer, and an ethylene vinyl acetate layer;

If the pulping and papermaking system uses mixed recycled office waste paper and/or newspapers as the main raw material, the adsorption layer is selected from: at least one of an epoxy acrylate layer, a styrene acrylic layer, and a polyacrylate layer. kind;

If the pulping and papermaking system uses chemical pulp, mechanical pulp and/or chemical mechanical pulp as the main raw material, the adsorption layer is selected from at least one of: a resin acid layer, a fatty acid ester layer, and a terpene resin layer. kind.

6. The device for capturing adhesives in a pulping and papermaking system according to claim 1, wherein the adsorption sample is fixed on the bottom of the accommodation cavity, and the adsorption sample faces the adsorption surface. The internal cavity of the accommodation cavity is described.

7. The device for capturing adhesives in a pulping and papermaking system according to claim 6, wherein the reaction vessel further includes a liquid inlet pipe and a liquid outlet pipe, and the accommodation cavity is a closed accommodation cavity, It is provided with a liquid inlet and a liquid outlet, the liquid inlet pipe is connected to the liquid inlet, the liquid outlet pipe is connected to the liquid outlet, and the liquid inlet is located in the accommodation cavity. The upper part of the liquid outlet is located on the side wall of the accommodation cavity;

or

The reaction vessel further includes a stirrer for maintaining flow of the papermaking slurry in the accommodation cavity.

8. The device for capturing adhesives in a pulping and papermaking system according to claim 1, wherein the accommodation cavity includes a cylindrical body, a specimen rack and a base, and the base is detachable. Installed at the bottom of the cylinder, the specimen rack is clamped and fixed between the cylinder and the base through the base. The specimen rack is provided with an adsorption installation area for fixing and adsorbing the specimen.

9. A method for capturing adhesives in a pulping and papermaking system, characterized by comprising the following steps: making the papermaking slurry at a predetermined sampling point in the pulping and papermaking system flow through an adsorption test with a surface capable of adsorbing granular adhesives The adsorption reaction occurs with the adsorption test piece, allowing the granular sticky substances in the papermaking slurry to be adsorbed on the surface of the adsorption test piece.

10. The method of capturing adhesives in a pulping and papermaking system according to claim 9, characterized in that the papermaking slurry flows toward the adsorption sample at an angle of 45-90 degrees with the surface of the adsorption sample.

11. The method for capturing sticky substances in a pulping and papermaking system according to claim 10, characterized in that the adsorption reaction includes an offline reaction and an online reaction,

The offline reaction is as follows: taking the papermaking slurry at a predetermined sampling point, placing it in a reaction container with an adsorption sample pre-installed, and maintaining the papermaking slurry in the reaction container by mechanical stirring, shaking, rotating, and/or turning over. React with the adsorbed sample in a flowing state;

The online reaction is: drawing a branch stream of papermaking slurry from a predetermined sampling point, and maintaining the papermaking slurry flowing through the surface of the adsorption sample to allow an adsorption reaction to occur.

12. The method of capturing adhesives in a pulping and papermaking system according to claim 10, characterized in that the time of the adsorption reaction is 5 seconds to 4 hours; the temperature of the adsorption reaction is 1°C-99 ° C _; in the adsorption reaction, the concentration of the papermaking slurry is 0.05%-15% based on the solid dry weight percentage.