Method for high efficient purification of white water mixed micro-fines in papermaking by bio-enzyme assisted hydrophilic / hydrophobic material ordered adhesion

Abstract

The application discloses a high-efficiency purification method for ordered adhesion of papermaking white water mixed micro-fine adhesive substances by using bio-enzyme to assist hydrophilic / hydrophobic materials. The method comprises the following steps: firstly, recovering the fine components in the white water; then, adding bio-enzyme; and treating under the conditions of a constant temperature of 25-60 DEG C, a pH of 6.0-9.0 and a treatment time of 10-120 min on a constant temperature shaker; and stirring and adhering for 15-60 min by using a rotor coated with fixed hydrophilic materials under the conditions of a temperature of 25-90 DEG C and a rotating speed of 150-1000 r / min, and then stirring and adhering for 15-60 min by using a rotor coated with fixed hydrophobic materials, wherein the stirring and adhering of the hydrophilic materials and the hydrophobic materials is circular once or more. The removal efficiency of the micro-fine adhesive substances in the papermaking white water reaches 60 % or more by using the method, the harm of the adhesive substances to the whole papermaking process is fundamentally solved, the method does not interfere with the chemical environment of the papermaking system, and the method has the advantages of low cost, simple operation, high efficiency and the like, and is suitable for application in various paper mills.

Description

TECHNICAL FIELD

[0001] The present application relates to the adhesive, especially relates to the papermaking white water mixed micro-fine adhesive purification method, specifically relates to the biological enzyme assisted hydrophilic / hydrophobic material ordered adhesion papermaking white water mixed micro-fine adhesive efficient purification method, and belongs to the technical field of fiber recycling. BACKGROUND

[0002] Waste paper is an important raw material for pulp and paper industry. The proportion of waste paper pulp in the total pulp consumption is increasing year by year, and the recycling of waste paper is of great significance for saving resources, saving energy and reducing environmental pollution. Adhesive is a collective noun, which represents all substances with temporary or permanent adhesion in the papermaking process. In actual production, due to the wide source of papermaking raw materials, the source and chemical composition of adhesive are very complex. Adhesive has the characteristics of deformation, surface negative charge, adhesion, and surface hydrophilicity or hydrophobicity, and is easily affected by the environment, such as temperature, time, pH value, etc. Adhesive can be divided into pulp adhesive and white water adhesive according to its environment. The pulp adhesive is mainly large adhesive, which is easy to detect and analyze due to its large particle size, and a relatively complete detection standard and removal method has been established. White water adhesive exists in the form of micro-fine adhesive, and its composition is more complex after the prohibition of waste paper. The volume of micro-fine adhesive is smaller than that of pulp adhesive, which makes its characteristics more complex and variable, and it is often mixed with fine fibers, fillers and other fine components, which has a greater impact on the papermaking system environment, reduces the paper machine running rate, and affects the paper quality.

[0003] At present, there is no special unit for the purification and removal of adhesive in the waste paper pulping and papermaking process, and the removal of adhesive is assisted in the existing units. Large adhesive is generally removed by screening, purification, flotation and other methods; while micro-fine adhesive is small in size and easy to destabilize, lacking an effective method for control. The control method of waste paper adhesive mainly includes three types: physical method, chemical method and biological method.

[0004] Physical method, also known as mechanical method or process control method, mainly includes disintegration, screening, purification, washing, dispersion, etc. Traditional physical methods are mainly used for large adhesive or larger size micro-fine adhesive. The chemical method for treating adhesive is to stabilize the water sample by adding different surfactants or emulsifiers to prevent the adhesive from automatically settling on the mechanical surface during the treatment process, and then removing the adhesive by physical sedimentation.

[0005] The commonly used chemical methods are chemical adsorption method, chemical dispersion method and chemical fixation method. The chemical dispersion method is to disperse the adhesive substances to prevent the small particles from flocculating again. The dispersing agent generally includes anionic surfactant, nonionic surfactant and cationic surfactant. The chemical adsorption method is to change the viscosity of the adhesive substances by chemical modification adsorption to avoid deposition. The adhesive substance control agents of the adsorption type mainly include nonionic polymer, talc, bentonite and cationic surfactant. Although the chemical method and the biological method have certain removal effect, they have problems of low efficiency and serious pollution. The removal efficiency is often affected by factors such as the performance of the equipment.

[0006] At present, the control of the micro-fine adhesive substances in the white water is mainly to make them exist stably in the white water or to make them solidify on the surface of the fibers to be taken out of the papermaking system. However, with the increase of the closed circulation degree of the white water and the increase of the recycling rate of the waste paper, the micro-fine adhesive substances solidified on the fibers will continuously return to the papermaking system with the waste paper, so that the micro-fine adhesive substances in the white water will accumulate more and more, and finally cause serious obstacle problems. Therefore, completely removing the micro-fine adhesive substances from the papermaking system and not participating in the flow of the waste paper recycling system is the fundamental way to solve the problem of the adhesive substances in the waste paper pulp.

[0007] The Chinese invention patent CN109024050B discloses a high-efficiency purification method for micro-fine adhesive substances in papermaking white water based on high-surface-roughness hydrophobic material. The method first recovers the fibers and part of the small components in the papermaking white water, uniformly stirs the white water suspension at 30-90℃ and a rotating speed of 50-2000r / min, and uses a high-surface-roughness hydrophobic material rotor to stir and adhere the micro-fine adhesive substances in the white water. The average removal rate of the adhesive substances is 29.58%, and the highest removal rate of the adhesive substances is 46.40%. However, this is the optimal case under various conditions of the purification method. Since the removal rate of the adhesive substances is lower than 50%, it is necessary to specially stop the machine to remove the micro-fine adhesive substances, which affects the continuity and stability of the production and prolongs the production cycle. SUMMARY

[0008] The purpose of the present application is to solve the problem of the continuous accumulation of mixed micro-fine adhesive substances in the closed circulation white water of the paper machine, which causes a series of serious obstacle problems. The present application provides a high-efficiency purification method for removing the micro-fine adhesive substances in the papermaking white water by using biological enzyme assisted hydrophilic / hydrophobic material to orderly adhere the mixed micro-fine adhesive substances in the papermaking white water, so as to fundamentally solve the harm of the adhesive substances to the entire papermaking process.

[0009] The purpose of the present application is achieved by the following technical solutions:

[0010] The high-efficiency purification method for biological enzyme assisted hydrophilic / hydrophobic material to orderly adhere the mixed micro-fine adhesive substances in the papermaking white water, characterized in that it comprises the following steps:

[0011] 1) recovering fibers in papermaking white water to obtain mixed micro-fines with particle size less than 100 μm, and a white water suspension to be treated containing fine fibers and fillers;

[0012] 2) adding biological enzymes into the white water suspension to be treated, the amount of biological enzymes being 40 U / L-80 U / L, and treating the white water suspension to be treated on a constant temperature shaker at a temperature of 25-60 ℃ and a pH of 6.0-9.0 for 10-120 min;

[0013] 3) stirring and adhering the white water treated in step 2) at a temperature of 25-90 ℃ and a rotating speed of 150-2000 r / min, first with a rotor coated with a hydrophilic material for 15-60 min, and then with a rotor coated with a hydrophobic material for 15-60 min, and repeating the stirring and adhering with the hydrophilic material first and then the hydrophobic material one or more times, so that the mixed micro-fines in the white water are adhered to the surfaces of the hydrophilic material and the hydrophobic material and then removed; the hydrophilic material has a static water contact angle ranging from 50° to 70°, and the hydrophobic material has a static water contact angle ranging from 100° to 120°.

[0014] To further achieve the purpose of the application, preferably, the main components of the glue in the papermaking white water are ethylene-vinyl acetate copolymer, alkyl alkene ketone dimer, polyacrylate polymer and / or styrene acrylate copolymer.

[0015] Preferably, the fibers in the papermaking white water are recovered by a dynamic filter instrument in a laboratory condition, and a multi-disc filter is used to recover the fibers and part of the fine fibers in the papermaking white water in production.

[0016] Preferably, the filter screen of the dynamic filter instrument is a standard screen, and the stirring speed is 200-1000 r / min; the filter screen of the multi-disc filter has a mesh range of 60-200.

[0017] Preferably, the biological enzyme is one or more of cellulase, hemicellulase, pectinase, amylase, lipase, esterase and laccase.

[0018] Preferably, the rotor is a symmetrical sheet, and the stirring mode is a convolute mode or a reciprocating mode.

[0019] Preferably, the white water to be treated in step 3) is treated at a temperature of 30-60 ℃ and a rotating speed of 100-1000 r / min for 15-60 min.

[0020] Preferably, the hydrophilic material is cotton fiber, hydrophilic polyurethane or non-woven fabric, and the hydrophobic material is foamed copper, polyester fiber or epoxy resin plate.

[0021] Preferably, the coating fixation is to coat the whole rotor with hydrophilic or hydrophobic material and then adopt detachable fixation mode.

[0022] Preferably, the number of stirring and adhering cycles of the hydrophilic material and then the hydrophobic material is 1-3 times.

[0023] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0024] 1. The average efficiency of removing white water micro-fine stickies by the present application with the aid of biological enzyme and physical adhesion is 13.12% higher than that of the same purification method without biological enzyme treatment. Although the increase is only more than 10%, it is difficult to take further improvement measures to substantially improve the efficiency of removing mixed micro-fine stickies in papermaking white water by more than 40% in the field. The present application significantly improves the removal efficiency of micro-fine stickies by more than 50% to 60% with the aid of biological enzyme, by first adhering to the surface of the hydrophilic material and then adhering to the surface of the hydrophobic material. This is a huge increase of 10% in the field which already has such a high removal efficiency of micro-fine stickies. It may be because the biological enzyme affects the physical and chemical properties of the surface of the stickies particles, and the new surface after treatment is respectively compatible with the properties of the hydrophilic / hydrophobic material, effectively improving the removal efficiency of complex micro-fine stickies particles in various waste paper pulp making white water.

[0025] 2. The purification efficiency of removing white water micro-fine stickies by the present application with the aid of biological enzyme and physical adhesion is 62.60-70.28%, and the average purification efficiency is 65.60%, which is increased by 37.8%. It can be said that this is an unexpected improvement. Because in the prior art, no matter how optimized and regardless of the way to remove micro-fine stickies in papermaking white water, single treatment (to papermaking white water) is difficult to achieve more than 50%, and the removal efficiency of micro-fine stickies in white water after adhering to the surface of the hydrophilic / hydrophobic material is also difficult to achieve 60%.

[0026] 3. The adhesion purification treatment of the present application is a physical way which does not interfere with the chemical environment of the papermaking system. Only by controlling the temperature, speed and adhesion time, and according to the ordered adhesion of the adhesion material to different components of stickies, the most ideal removal degree is achieved, the high-efficiency purification of papermaking white water is realized without stopping, the continuity and stability of production are ensured, the stoppage cleaning period is prolonged by at least 2-3 times due to the interference of stickies in the prior art is avoided, the normal production and stable product quality are maintained, and the normal operation of the paper machine and the stable quality of the paper product are ensured.

[0027] 4. The method of the present application can significantly remove complex micro-fine stickies in various papermaking white water, especially in the case of multiple sources and complex components of stickies, the effect is better, the interference of the chemical environment of the white water is minimized, the stability of the system is maintained, the closed circulation use of papermaking white water is effectively promoted, and the use value is higher.

[0028] 5. The method of the present application has the advantages of simple operation, low cost and obvious advantages in production, and is suitable for application in various paper mills. DETAILED DESCRIPTION

[0029] In order to further understand the present application, the present application is further described below in conjunction with examples, but the embodiments of the present application are not limited thereto.

[0030] The present application is a method for high-efficiency purification of mixed micro-fine stickies in papermaking white water by using biological enzyme to assist ordered adhesion of hydrophilic / hydrophobic materials, which comprises the following steps: recovering fibers in papermaking white water to obtain mixed micro-fine stickies with a particle size less than 100 μm, and a white water suspension to be treated containing fine fibers and fillers; adding biological enzyme into the white water suspension to be treated, wherein the amount of the biological enzyme is 40 U / L-80 U / L, and the white water suspension to be treated is treated on a constant-temperature shaking table under the conditions of a temperature of 25-60 °C and a pH of 6.0-9.0 for 10-120 min; stirring and adhering the treated white water to be purified at a temperature of 25-90 °C and a rotation speed of 150-2000 r / min by using a rotor coated with a fixed hydrophilic material for 15-60 min, and then stirring and adhering the white water by using a rotor coated with a fixed hydrophobic material for 15-60 min, wherein the stirring and adhering of the hydrophilic material and the hydrophobic material are cycled once or more times, so that the mixed micro-fine stickies in the white water are adhered to the surfaces of the hydrophilic material and the hydrophobic material and then removed; the surface of the hydrophilic material has a static water contact angle in the range of 50°-70°; and the surface of the hydrophobic material has a static water contact angle in the range of 100°-120°. The present application only needs to be performed under the conditions of controlling the temperature and the rotation speed of the papermaking white water once, and belongs to single-time treatment.

[0031] The technical measure is to find that the hydrophilic material surface is adhered first, and then the hydrophobic material surface is adhered; the sequence is repeated one or more times, and the purified papermaking white water mixed with micro-fine adhesive substances has an unexpected effect, even if the hydrophobic material surface is adhered first and then the hydrophilic material surface is adhered, the effect is far less than that of the present application, and the removal efficiency of the micro-fine adhesive substances in the papermaking white water is less than 50%. On the other hand, the biological enzyme treatment has a certain synergistic effect with the above-mentioned adhesion mode; generally speaking, after the purification of the papermaking white water mixed with micro-fine adhesive substances reaches more than 40% efficiency, it is difficult to have substantial improvement by taking further improvement measures. The present application significantly improves the removal efficiency of the micro-fine adhesive substances to more than 50% to 60% under the assistance of biological enzymes, which is a huge improvement of 10% in the field with such a high removal efficiency of micro-fine adhesive substances. It may be because the biological enzyme control method can disperse the adhesive substance particles into several small size particles, making it difficult for them to re-agglomerate in the system, and the biological enzymes have specificity and high efficiency, and the biological enzymes commonly used in the papermaking industry at present include cellulase, hemicellulase, pectinase, amylase, lipase, esterase, laccase, and compound enzymes. Among them, cellulase mainly hydrolyzes the glycosidic bond on the surface of fibers or fine fibers to promote the dispersion of adhesive substance particles into several small size particles; esterase acts on the ester bond that plays an adhesive role, which can reduce the viscosity of the adhesive substance, making it difficult to adhere and re-agglomerate; other enzymes also have their own action characteristics.

[0032] The hydrophilic material surface static water contact angle is in the range of 50°-70°; the hydrophobic surface static water contact angle is in the range of 100°-120°; the hydrophilic material is, for example, cotton fiber, hydrophilic polyurethane, non-woven fabric material, etc.; and the hydrophobic material is, for example, foamed copper, polyester fiber, epoxy resin plate material, etc.

[0033] The biological enzyme assistance of the present application is very friendly to the environment, the adhesion purification treatment is a physical method, which does not interfere with the chemical environment of the papermaking system, and the purified white water is reused in the papermaking system for continuous circulation.

[0034] Example 1

[0035] The label paper with pressure-sensitive adhesive and the copy paper are prepared into slurry according to the ratio of 1:49, then screened, and then filtered by a dynamic water filter instrument with a 200-mesh filter screen to recover the components containing fibers, fillers, etc. in it, to obtain laboratory papermaking white water containing fine fibers, micro-fine adhesive substances and fillers, etc. AKD is added to make the content of AKD in the white water 0.1%, so that the adhesive substances contained in the white water are: ethylene-vinyl acetate copolymer, AKD, polyacrylate substance. Then the white water is preheated, and part of the preheated white water is taken to measure the content of adhesive substances in it by a laser particle size instrument, which is 3.77mm 3 / mL.

[0036] The preheated white water is treated with cellulase, and the cellulase is added in an amount of 40 U / L. The white water is treated in a constant temperature shaker at a temperature of 25°C and a pH of 7.85 for 60 min, so that the cellulase and the white water are fully reacted, and the adhesive particles are dispersed into small particles.

[0037] The white water is treated with cellulase, and the cellulase is added in an amount of 40 U / L. The white water is treated in a constant temperature shaker at a temperature of 25°C and a pH of 7.85 for 60 min, so that the cellulase and the white water are fully reacted, and the adhesive particles are dispersed into small particles. 3 / mL, and the removal efficiency of the adhesive particles after the treatment is 63.16%.

[0038] The preheated white water is treated with cellulase, and the cellulase is added in an amount of 40 U / L. The white water is treated in a constant temperature shaker at a temperature of 25°C and a pH of 7.85 for 60 min, so that the cellulase and the white water are fully reacted, and the adhesive particles are dispersed into small particles. 3 / mL, and the removal efficiency of the adhesive particles after the treatment is 63.16%.

[0039] Example 2

[0040] The preheated white water is treated with cellulase, and the cellulase is added in an amount of 40 U / L. The white water is treated in a constant temperature shaker at a temperature of 25°C and a pH of 7.85 for 60 min, so that the cellulase and the white water are fully reacted, and the adhesive particles are dispersed into small particles.

[0041] The white water treated by cellulase was subjected to adhesion stirring at a temperature of 90°C and a rotation speed of 150 r / min. The adhesion materials were first bound to the rotor. Hydrophilic cotton fiber materials were first used for stirring for 60 min, and then hydrophobic nylon materials were used for stirring for 60 min. Sampling was performed. A laser particle size instrument and a lipophilic fluorescent tracer were used to detect the number and size of micro-fine adhesive particles in the white water in a unit volume. The total volume content of the micro-fine adhesive particles in the white water in a unit volume was calculated to be 1.29 mm 3 / mL. The adhesion removal efficiency of the micro-fine adhesive particles after treatment was calculated to be 65.91%.

[0042] Example 3

[0043] The white water after filtration treatment in Example 1 was treated by using cellulase and esterase in a ratio of 1:1. The amount of biological enzyme (cellulase and esterase) added was 60 U / L. The treatment was performed on a constant temperature shaker at a temperature of 40°C and a pH of 7.95 for 60 min. The cellulase and the micro-fine adhesive particles mixed in the white water were allowed to fully react, so as to promote the dispersion of the adhesive particles into a plurality of small-size particles.

[0044] The white water after treatment by the compounded enzyme was subjected to adhesion stirring at a temperature of 25°C and a rotation speed of 150 r / min. The adhesion materials were first bound to the rotor. Hydrophilic cotton fiber materials were first used for stirring for 15 min, and then hydrophobic nylon materials were used for stirring for 15 min. Sampling was performed. A laser particle size instrument and a lipophilic fluorescent tracer were used to detect the number and size of micro-fine adhesive particles in the white water in a unit volume. The total volume content of the micro-fine adhesive particles in the white water in a unit volume was calculated to be 1.12 mm 3 / mL. The adhesion removal efficiency of the micro-fine adhesive particles after treatment was calculated to be 70.28%.

[0045] Example 4

[0046] The white water after filtration treatment in Example 1 was treated by using hemicellulase. The amount of hemicellulase added was 40 U / L. The treatment was performed on a constant temperature shaker at a temperature of 60°C and a pH of 7.4 for 60 min. The cellulase and the micro-fine adhesive particles mixed in the white water were allowed to fully react, so as to promote the dispersion of the adhesive particles into a plurality of small-size particles.

[0047] The white water after treatment by hemicellulase was subjected to adhesion stirring at a temperature of 90°C and a rotation speed of 150 r / min. The adhesion materials were first bound to the rotor. Hydrophilic cotton fiber materials were first used for stirring for 60 min, and then hydrophobic nylon materials were used for stirring for 60 min. Sampling was performed. A laser particle size instrument and a lipophilic fluorescent tracer were used to detect the number and size of micro-fine adhesive particles in the white water in a unit volume. The total volume content of the micro-fine adhesive particles in the white water in a unit volume was calculated to be 1.30 mm 3 / mL, the adhesion removal efficiency of the micro-fine stickies after treatment was 65.71%.

[0048] Example 5

[0049] The white water after filtration treatment in Example 1 was treated by using esterase, and the white water was treated for 60 min on a constant temperature shaker at a temperature of 40℃, a cellulase addition amount of 80 U / L, and a pH of 6, so that the cellulase and the micro-fine stickies mixed in the white water fully reacted and the stickies particles were dispersed into several small size particles.

[0050] The white water after esterase treatment was subjected to adhesion stirring at a temperature of 60℃ and a rotation speed of 150 r / min, and the adhesion material was first bound to the rotor. Hydrophilic cotton fiber material was first used for stirring for 60 min, and then hydrophobic nylon material was used for stirring for 60 min. Sampling was performed, and the number and size of the micro-fine stickies particles in the white water per unit volume were detected by using a laser particle size instrument and a lipophilic fluorescent tracer. The total volume content of the micro-fine stickies particles in the white water per unit volume was 1.41 mm3 / mL, and the adhesion removal efficiency of the micro-fine stickies after treatment was 62.60%.

[0051] In Example 1, the enzyme treatment temperature was 25℃, the pH value was 7.85, and the treatment time was 60 min, and the removal efficiency of the micro-fine stickies reached more than 60%, which was very high. In Example 3, the enzyme treatment temperature was 40℃, the pH value was 7.95, and the treatment time was 60 min, and the removal efficiency of the micro-fine stickies reached more than 70%. The enzyme treatment time and pH value were the same in Example 1, Example 3, and Example 4, and the temperatures were 25℃, 40℃, and 60℃, respectively. The removal efficiency of the micro-fine stickies first increased and then decreased, but as the temperature increased, the removal efficiency of the micro-fine stickies in the white water increased to a certain extent, and the content of the micro-fine stickies in the white water significantly decreased. Cellulase was used in Example 1-3, hemicellulase was used in Example 4, and esterase was used in Example 5. The removal efficiency of the micro-fine stickies in the white water after treatment by different enzymes and then using different materials for adhesion changed little, which indicated that the effect of the ordered adhesion of different biological enzymes and hydrophilic and hydrophobic materials was good.

[0052] Example 6

[0053] The white water after filtration treatment in Example 1 was treated by using esterase, and the white water was treated for 60 min on a constant temperature shaker at a temperature of 40℃, a cellulase addition amount of 80 U / L, and a pH of 6, so that the cellulase and the micro-fine stickies mixed in the white water fully reacted and the stickies particles were dispersed into several small size particles.

[0054] The white water after cellulase treatment is subjected to adhesion stirring at a temperature of 25 DEG C and a rotating speed of 150 r / min, the adhesion materials are all bound to the rotor, the hydrophilic cotton fiber material is first used for stirring for 60 min, then the hydrophobic nylon material is used for stirring for 60 min, sampling is carried out, the number and size of the micro fine adhesive particles in the white water in unit volume are detected by using a laser particle size instrument and a lipophilic fluorescent tracer, and the total volume content of the micro fine adhesive particles in unit volume is calculated as 1.29 mm 3 / mL, and the adhesion removal efficiency of the micro fine adhesive particles after treatment is calculated as 65.93%.

[0055] In the present application, in Example 1, the removal efficiency of the micro fine adhesive particles in the white water without adding biological enzyme treatment is 52.48%, and the adhesion removal efficiency of the micro fine adhesive particles is 63.16%; the other examples are similar; compared with the same purification method without adding biological enzyme treatment, the average efficiency of removing the micro fine adhesive particles in the white water by using biological enzyme assisted physical adhesion is improved by 13.12%, which is more than 10%, but after the micro fine adhesive particles in the white water reach an efficiency of more than 40%, it is difficult to take further improvement measures to have substantial improvement, and it is difficult to effectively remove the micro fine adhesive particles in the white water after the removal efficiency of the micro fine adhesive particles in the white water reaches 40%. In the present application, under the assistance of biological enzyme, the removal efficiency of the micro fine adhesive particles by using hydrophilic material surface adhesion and then using hydrophobic material surface adhesion is increased from more than 50% to 60%, which is a great improvement of 10% in the field with such a high removal efficiency of the micro fine adhesive particles.

[0056] The highest removal efficiency of the micro fine adhesive particles in the white water by using single biological enzyme is 27.2% in the master thesis of Tang Yanan, "Unstable characteristics and purification of white water micro fine adhesive particles under the action of biological enzyme", and it is known by those skilled in the art that single treatment is difficult to reach more than 40%; the purification efficiency of removing the micro fine adhesive particles in the white water by using biological enzyme assisted physical adhesion is 62.60-70.28%, and the average purification efficiency is 65.60%, which is improved by 37.8%. It can be said that this is an unexpected improvement, because in the prior art, no matter how to optimize or remove the micro fine adhesive particles in the white water, single treatment (to the white water) is difficult to reach more than 50%, and the removal efficiency of the micro fine adhesive particles in the white water after adhesion of the hydrophilic / hydrophobic material is also difficult to reach 60%.

[0057] The method does not interfere with the chemical environment of the papermaking system, and after the removal efficiency of the fine colloidal substance in the papermaking white water reaches more than 50%, the fine colloidal substance can be removed without stopping the machine, the repeated stopping of the machine to remove the fine colloidal substance in the papermaking white water in the production process can be avoided, the normal operation of the production can be maintained, the product quality is stable, the smooth operation of the papermaking system is ensured, the purification efficiency of the biological enzyme auxiliary physical adhesion removal of the fine colloidal substance in the white water is more than 60%, the harm of the colloidal substance to the production and the product quality is fundamentally solved or alleviated, the machine stopping and cleaning period caused by the colloidal substance obstacle is avoided, the production period is shortened by more than 2-3 times compared with the prior art. Moreover, the method is simple in operation and low in cost, and has obvious advantages in production.

[0058] The protection scope of the present application is not limited by the above examples, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present application shall be equivalent alternative methods, and all shall be included in the protection scope of the present application.

Claims

1. A method for the efficient purification of white water from papermaking by bio-enzyme assisted ordered adhesion of hydrophilic / hydrophobic materials to fine-sized stickies, characterized in that The method comprises the following steps: 1) recovering fibers in papermaking white water to obtain a mixed fine adhesive substance with a particle size less than 100 μm, and a white water suspension to be treated containing fine fibers and fillers; the main components of the adhesive substance in the papermaking white water are ethylene-vinyl acetate copolymer, alkyl alkene ketone dimer, polyacrylate polymer and / or styrene acrylate copolymer; 2) adding a biological enzyme to the white water suspension to be treated, the amount of the biological enzyme being 40 U / L to 80 U / L, and treating the white water suspension to be treated on a constant-temperature shaking table at a temperature of 25-60 °C and a pH of 6.0-9.0 for 10-120 min; the biological enzyme is one or more of cellulase, hemicellulase, pectinase, amylase, lipase, esterase and laccase; 3) stirring and adhering the white water to be purified after the treatment in step 2) at a temperature of 25-90 °C and a rotating speed of 150-2000 r / min, first using a rotor with a surface coated with a hydrophilic material to stir and adhere for 15-60 min, and then using a rotor with a surface coated with a hydrophobic material to stir and adhere for 15-60 min, the stirring and adhering of the hydrophilic material first and then the hydrophobic material being repeated one or more times, so that the mixed fine adhesive substance in the white water is adhered to the surfaces of the hydrophilic material and the hydrophobic material and then removed; the surface of the hydrophilic material has a static water contact angle ranging from 50° to 70°, and the surface of the hydrophobic material has a static water contact angle ranging from 100° to 120°; the hydrophilic material is cotton fiber, hydrophilic polyurethane or non-woven fabric; and the hydrophobic material is foamed copper, polyester fiber or epoxy resin plate.

2. The bio-enzyme assisted hydrophilic / hydrophobic material ordered adhesion purification method for papermaking white water mixed micro-fine stickies according to claim 1, characterized in that: The fibers in the papermaking white water are recovered by using a dynamic filter in a laboratory, and the fibers and part of the fine fibers in the papermaking white water are recovered by using a multi-disc filter in production.

3. The bio-enzyme assisted hydrophilic / hydrophobic material ordered adhesion method for purifying papermaking white water mixed micro-fines and stickies with high efficiency according to claim 2, characterized in that: The filter screen of the dynamic filter is a standard screen, and the stirring speed is 200-1000 r / min; the filter screen of the multi-disc filter has a mesh range of 60-200.

4. The bio-enzyme assisted hydrophilic / hydrophobic material ordered adhesion purification method of papermaking white water mixed micro-fine stickies according to claim 1, characterized in that: The rotor is symmetrical and in the form of a sheet; and the stirring mode is a convolute mode or a reciprocating mode.

5. The bio-enzyme assisted hydrophilic / hydrophobic material ordered adhesion purification method for fine and sticky substances in papermaking white water mixture according to claim 1, characterized in that The hydrophilic material or the hydrophobic material is coated on the entire rotor, and then detachably fixed.

6. The bio-enzyme assisted hydrophilic / hydrophobic material ordered adhesion purification method for papermaking white water mixed micro-fine stickies according to claim 1, characterized in that The number of times of the stirring and adhering of the hydrophilic material first and then the hydrophobic material is 1-3.