阅读说明：本技术 一种模塑制品用浆的制备方法 (Method for preparing pulp for molded product ) 是由 叶锦强 胡可一 周永锴 于 2021-08-13 设计创作，主要内容包括：本发明公开一种模塑制品用浆的制备方法,包括如下步骤：(1)将农林废弃物清洗备料后,加入生物酶进行预处理,得到酶解后的浆料A；(2)将步骤(1)中得到的浆料A进行臭氧浸渍处理,得到臭氧处理后的浆料B；(3)将步骤(2)中得到的浆料B进行高浓磨浆、低浓磨浆后,筛选净化得到所述模塑制品用浆。本发明以价格低廉的可降解农林废弃纤维资源为原料,将农林废弃纤维采用生物酶和臭氧浸渍处理结合,更好的润胀和软化纤维,极大程度的进行了木素的降解。(The invention discloses a preparation method of pulp for a molded product, which comprises the following steps: (1) cleaning and preparing agricultural and forestry waste, and adding biological enzyme for pretreatment to obtain slurry A after enzymolysis; (2) carrying out ozone dipping treatment on the slurry A obtained in the step (1) to obtain slurry B after ozone treatment; (3) and (3) carrying out high-concentration pulping and low-concentration pulping on the pulp B obtained in the step (2), and screening and purifying to obtain the pulp for the molded product. The invention takes the degradable agriculture and forestry waste fiber resource with low price as the raw material, combines the agriculture and forestry waste fiber by adopting biological enzyme and ozone impregnation treatment, better swells and softens the fiber, and greatly degrades the lignin.)

1. A method for preparing a slurry for a molded article, comprising the steps of:

(1) cleaning and preparing agricultural and forestry waste, and adding biological enzyme for pretreatment to obtain slurry A after enzymolysis;

(2) carrying out ozone dipping treatment on the slurry A obtained in the step (1) to obtain slurry B after ozone treatment;

(3) and (3) carrying out high-concentration pulping and low-concentration pulping on the pulp B obtained in the step (2), and screening and purifying to obtain the pulp for the molded product.

2. The method of preparing pulp for molded articles according to claim 1, wherein in the step (1), the agricultural and forestry residues include at least one of straw, reed, bagasse, bamboo.

3. The method for producing molded article pulp according to claim 1, wherein in the step (1), the bio-enzyme comprises at least one of cellulase, hemicellulase and lignin degrading enzyme, and the amount of the bio-enzyme added is 1 to 1.5 kg/ton of oven dried pulp; the pretreatment temperature is 40-50 deg.C, and the pretreatment time is 30-40 min.

4. The method of producing molded article pulp of claim 3, wherein the weight ratio of the cellulase, hemicellulase and lignin degrading enzyme is: cellulase: hemicellulase (b): lignin-degrading enzyme 4-6:1-2: 2-3.

5. The method of producing molded article pulp of claim 4, wherein the weight ratio of the cellulase, hemicellulase and lignin degrading enzyme is: cellulase: hemicellulase (b): lignin-degrading enzyme 6:1: 2.

6. The method for producing a pulp for molded articles as claimed in claim 1, wherein the specific process of the ozone impregnation treatment in the step (2) is: and adjusting the pH value and the slurry concentration of the slurry A, adding the slurry A into a reaction kettle, uniformly stirring, adjusting an ozone generator, and controlling the concentration and the dosage of introduced ozone to obtain a slurry B.

7. The process for producing a pulp for molded articles as claimed in claim 6, wherein in the step (2), the pH of the pulp A is 2 to 4; the pulp concentration of the pulp A is 10-15 wt%; the stirring temperature is 50-70 ℃, the concentration of ozone is 100-150mg/L, and the dosage of ozone is 0.5-1.0 wt% of oven-dried pulp.

8. The method of preparing pulp for molded articles as claimed in claim 7, wherein the concentration of ozone in the step (2) is 120mg/L and the amount of ozone used is 0.8 wt% of the oven dried pulp.

9. A molding syrup obtained by the process for producing a molding syrup as claimed in any of claims 1 to 8.

10. Use of the pulp for molded articles according to claim 9 for the preparation of environmentally friendly pulp molded articles.

Technical Field

The invention relates to the field of pulping, in particular to a preparation method of pulp for a molded product.

Background

The policy of 'forbidden plastic order' is continuously applied, the environmental pollution caused by plastic is increasingly serious, more and more people realize the harm of plastic, and the trend that the environment-friendly paper pulp molding product replaces the plastic product is inevitable. The national export series policy of 7 months in 2017 limits import of solid waste, the quantity of imported waste paper is sharply reduced, paper making raw materials are initiated, and the gap is as high as more than 2500 million t/a. At present, the agricultural and forestry waste fibers are more than 20 hundred million tons per year, mainly comprise straws, reeds, bagasse, waste wood, dried branches, brush wood, sawdust and the like, the resource conversion utilization rate is less than 20 percent, the main treatment mode is incineration, the environment is seriously polluted, fire disasters are easily caused, and the life and property safety is harmed.

At present, the problem of serious shortage of raw material supply exists in the traditional preparation of pulp molding products by taking waste paper as raw material, the pretreatment technology of the agricultural and forestry waste fiber is not mature at present, and the application in the pulp molding products is not promoted yet.

Disclosure of Invention

Based on this, the object of the present invention is to overcome the above-mentioned disadvantages of the prior art and to provide a process for the preparation of a pulp for molded articles.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a method for preparing a pulp for molded articles, comprising the steps of:

(1) cleaning and preparing agricultural and forestry waste, and adding biological enzyme for pretreatment to obtain slurry A after enzymolysis;

(2) carrying out ozone dipping treatment on the slurry A obtained in the step (1) to obtain slurry B after ozone treatment;

(3) and (3) carrying out high-concentration pulping and low-concentration pulping on the pulp B obtained in the step (2), and screening and purifying to obtain the pulp for the molded product.

The invention takes the degradable agriculture and forestry waste fiber resource with low price as the raw material, combines the agriculture and forestry waste fiber by adopting biological enzyme and ozone impregnation treatment, better swells and softens the fiber, and greatly degrades the lignin. After the thick liquids that obtain after the processing carries out the high-consistency refining, high-consistency refining equipment adopts utility model patent, application number 202022786736X's a high-efficient high-consistency refining device, and it is effectual to grind the thick liquid, and material fibre divides the silk to improve happy paper pulp quality. The invention adopts low-consistency pulp grinding after high-consistency pulp grinding, and the performance of the pulp for molding products can meet the requirements after the treatment of high-consistency and low-consistency two-stage pulp grinding. The beating degree of the pulp obtained after high-concentration pulping is 15-20 degrees SR, and the beating degree of the pulp obtained after low-concentration pulping is 25-30 degrees SR.

Preferably, in the step (1), the agricultural and forestry waste includes at least one of straw, reed, bagasse and bamboo. Because the country limits the imported waste paper, the paper-plastic fiber raw material with stable source and low price is paid attention by many people, the invention adopts agricultural and forestry waste as the raw material, reduces the degree of dependence of the paper pulp molding industry of China on the imported waste paper and the tank leftover material, effectively solves the problem of insufficient productivity caused by the shortage of the raw material in the paper pulp molding industry, and improves the market competitiveness of the environment-friendly paper pulp molded product.

Preferably, in the step (1), the biological enzyme comprises at least one of cellulase, hemicellulase and lignin degrading enzyme, and the addition amount of the biological enzyme is 1-1.5 kg/ton of oven-dried pulp; the pretreatment temperature is 40-50 deg.C, and the pretreatment time is 30-40 min. The invention selects cellulase, hemicellulase and lignin degrading enzyme to respectively hydrolyze cellulose, hemicellulose and lignin, promotes the swelling and loosening of fibers, and accelerates the swelling and softening of the fibers.

Preferably, the weight ratio of the cellulase to the hemicellulase to the lignin degrading enzyme is: cellulase: hemicellulase (b): lignin-degrading enzyme 4-6:1-2: 2-3. After a large amount of creative experiments, the inventor of the application finds that the performance of the prepared slurry is better in all aspects when the biological enzyme is in the selected range of the weight parts.

Further preferably, the weight ratio of the cellulase to the hemicellulase to the lignin degrading enzyme is: cellulase: hemicellulase (b): lignin-degrading enzyme 6:1: 2. After a large amount of creative experiments, the inventor of the application finds that the performance of the prepared slurry reaches the best in all aspects within the selection range of the weight parts of the biological enzyme.

Preferably, in the step (2), the specific process of the ozone impregnation treatment is as follows: and adjusting the pH value and the slurry concentration of the slurry A, adding the slurry A into a reaction kettle, uniformly stirring, adjusting an ozone generator, and controlling the concentration and the dosage of introduced ozone to obtain a slurry B. Further preferably, in the step (2), the pH value of the slurry A is 2-4; the pulp concentration of the pulp A is 10-15 wt%; the stirring temperature is 50-70 ℃, the concentration of ozone is 100-150mg/L, and the dosage of ozone is 0.5-1.0 wt% of oven-dried pulp. The safe ozone bleaching experimental device disclosed by the invention patent, application number 201710940280.8, is used for carrying out ozone dipping treatment, accurately controlling the generation amount and the addition amount of ozone, ensuring the timeliness of reaction, and being convenient and flexible to operate, safe and reliable.

Preferably, in the step (2), the concentration of the ozone is 120mg/L, and the amount of the ozone is 0.8 wt% of the oven-dried pulp. After a large amount of creative experiments, the inventor of the application finds that the performance of the prepared slurry reaches the best in all aspects within the selection range of the weight parts of the biological enzyme.

In addition, the invention provides the molding pulp prepared by the preparation method of the molding pulp. Further, the invention provides application of the pulp for the molded product in preparing an environment-friendly pulp molded product. The process for preparing the environment-friendly pulp molded product is shown in figure 2.

Compared with the prior art, the invention has the beneficial effects that: the invention creatively combines the fiber green environment-friendly production technology and the pulp molding processing technology to produce the environment-friendly pulp molding product, and the technology belongs to the leading level of the industry.

Drawings

FIG. 1 is a flow chart of a process for preparing a pulp for molded articles;

FIG. 2 is a process flow diagram of an environment-friendly pulp molded product.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to the accompanying drawings and specific embodiments. In the examples, the experimental methods used were all conventional methods unless otherwise specified, and the materials, reagents and the like used were commercially available without otherwise specified.

The preparation method of the pulp for the molded product comprises the following steps, and the preparation process flow chart of the pulp for the molded product is shown in figure 1:

(1) cleaning and preparing agricultural and forestry waste, and adding biological enzyme for pretreatment to obtain slurry A after enzymolysis; the agricultural and forestry waste comprises at least one of straw, reed, bagasse and bamboo; the biological enzyme comprises at least one of cellulase, hemicellulase and lignin degrading enzyme, and the addition amount of the biological enzyme is 1-1.5 kg/ton of oven-dried pulp; the pretreatment temperature is 40-50 ℃, and the pretreatment time is 30-40 min;

(2) carrying out ozone dipping treatment on the slurry A obtained in the step (1) to obtain slurry B after ozone treatment; in the ozone dipping treatment process, the pH value of the slurry A is 2-4; the pulp concentration of the pulp A is 10-15 wt%; the stirring temperature is 50-70 ℃, the concentration of ozone is 100-150mg/L, and the dosage of ozone is 0.5-1.0 wt% of oven-dried pulp;

(3) after high-concentration pulping and low-concentration pulping are carried out on the pulp B obtained in the step (2), screening and purifying to obtain pulp for the molded product; the beating degree of the pulp obtained after high-concentration pulping is 15-20 degrees SR, and the beating degree of the pulp obtained after low-concentration pulping is 25-30 degrees SR.

In the process for producing a syrup for molded articles described in examples 1 to 6 of the present invention, the parameters were selected as shown in Table 1:

table 1 examples each parameter selection

Meanwhile, the invention sets up the comparative example, in the preparation method of the pulp for molded products described in comparative examples 1-6 of the invention, each parameter is selected as shown in table 2, when the bio-enzyme treatment of comparative example 1, no lignin-degrading enzyme is contained, and the rest components, parts by weight and preparation method are completely the same as example 2; comparative example 2 in the case of the bio-enzyme treatment, the amount of cellulase used was less than the specific range provided by the present invention, and the remaining components, parts by weight, and preparation methods were completely the same as those in example 2; comparative example 3 in the case of the bio-enzyme treatment, the amount of cellulase used was more than the specific range provided by the present invention, and the remaining components, parts by weight, and preparation methods were completely the same as those in example 2; comparative example 4 ozone treatment, ozone concentration is less than the specific range provided by the present invention, and the remaining components, parts by weight, preparation method are exactly the same as example 2; comparative example 5 ozone treatment, ozone concentration is greater than the specific range provided by the present invention, and the remaining components, parts by weight, preparation method are completely the same as example 2; comparative example 6 ozone treatment, the amount of ozone used was less than the specific range provided by the present invention, and the remaining components, parts by weight, and preparation method were exactly the same as in example 2; comparative example 7 ozone treatment, ozone amount is greater than the specific range provided by the present invention, and the remaining components, parts by weight, preparation method and example 2 are completely the same;

table 2 selection of parameters in comparative examples

Test example 1 mechanical Properties of slurry

Test standards: according to GB/T2677.2-2011, measuring the moisture of a sample; quantitative determination: GB/T22811-2008; determination of tensile Strength: GB/T22364-2018; determination of tear Strength: GB/T455-2008; taking a certain amount of the pulp of the examples and the comparative examples, papermaking 80g of the pulp, and carrying out mechanical property test on the paper.

And (3) test results: as shown in tables 3 and 4 below;

table 3 mechanical property test results of examples

Table 4 comparative example mechanical property test results

As can be seen from the above table, the tensile index and burst index of the slurry prepared in the examples of the present invention are significantly higher than those of the slurry prepared in the comparative examples of the present invention. Comparative example 1 does not contain lignin-degrading enzyme, cannot well remove wood-plastic and swelling fibers in the process of biological enzyme treatment, and finally obviously reduces the tensile index and the burst index. The dosage of the cellulase in the comparative example 2 is less than the specific range provided by the invention, and the dosage of the cellulase in the comparative example 3 is more than the specific range provided by the invention, so that the tensile index and the burst index are obviously reduced, which shows that the selection of the dosage of the biological enzyme is obtained by a great amount of tests of the inventor, and the effect is obviously deteriorated when the mixture ratio is not in the protection range of the invention. Comparative examples 4 to 6 are the tensile index and burst index were significantly reduced when the ozone concentration or the amount of ozone used in the ozone treatment process was outside the range of the present invention.

Test example 2 egg tray performance test

The test process comprises the following steps: the molded pulp for the molded goods prepared in the examples and the comparative examples is prepared into the environment-friendly pulp molded product-egg tray according to the preparation process of the process flow chart of the environment-friendly pulp molded product shown in figure 2, and the processes for preparing the egg tray are completely the same as the processes for preparing the molded pulp for the goods only in the examples and the comparative examples.

Test standards: testing the weight, moisture, water resistance, compression resistance and brittleness of the sample according to a BB/T0015-1999 pulp molding egg tray;

and (3) test results: as shown in table 5 below; wherein, the qualified water resistance means that the water is not leaked after 48 hours; the qualified compression resistance means that the deformation is less than 3mm when the material is pressed for 830N; the brittleness is qualified, namely 4 corner holes respectively bear a weight of 0.5kg and are kept for 1min, and no breakage or crack exists;

table 5 test results of the properties of the environmentally friendly pulp molded product, egg tray

As can be seen from Table 5, the slurry for molded articles prepared in the embodiment of the present invention is prepared to obtain the environmentally friendly pulp molded article, i.e., the egg tray, according to the preparation process of the process flow diagram of the environmentally friendly pulp molded article shown in FIG. 2. The pulp for the molded products prepared by the comparative example of the invention is also tested by the applicant, and the strength performance of the pulp cannot meet the requirement well, so that the prepared egg tray has unqualified water resistance, pressure resistance, brittleness and the like and cannot reach the use standard.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.