Organic fertilizer coated paper mulching film and manufacturing method thereof

Abstract

The invention provides an organic fertilizer coated paper mulching film and a manufacturing method thereof, the organic fertilizer coated paper mulching film comprises a surface coating layer, core paper pulp and a bottom sizing layer which are stacked, the surface coating layer is mainly composed of starch, MFC type nanocellulose, sodium humate and urea according to the percentage of 10-30%: 10-30%: 30-50%: 10-30%, and the bottom sizing layer is mainly composed of starch, MFC type nanocellulose, sodium humate and urea according to the percentage of 10-30%: 10-30%: 30-50%: 10-30%. The core paper pulp is mainly composed of OCC pulp, and the bottom sizing layer is mainly composed of starch. The main raw materials of the organic fertilizer coated paper mulching film are starch, MFC type nanocellulose, sodium humate, urea and OCC slurry, the mulching film can be degraded by microorganisms in soil after being used for a certain period, pollution cannot be generated, 98% of decomposed products are natural single plant fibers, 0-2% of decomposed products are nitrogen fertilizers, the decomposed products can be absorbed by crops and provide nutrients for the crops, and the yield of the crops is increased. The use of chemical fertilizers is reduced, and the economic value is higher.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural materials, and in particular to an organic fertilizer coated paper mulch film and a method for manufacturing the organic fertilizer coated paper mulch film. Background Art

[0002] Agricultural plastic film (abbreviated as agricultural film) has been widely used in the past 40 years, but the long-term and large-scale use of agricultural film and the lack of effective recycling and treatment have led to the aggravation of "white pollution". At present, my country is the country with the largest use of mulch film and the largest area of ​​mulch film coverage in the world. The area of ​​mulch film covering crops is nearly 300 million mu, and about 1.5 million tons of mulch film are used every year. Because it is difficult to recycle and degrade, the massive amount of mulch film fragments has brought "white pollution" that cannot be ignored, and has greatly affected the ecological environment in some areas. In the cotton-growing area of ​​Xinjiang, the most intuitive feeling is that cotton can't be sown during sowing operations. Large pieces of mulch film fragments are wrapped around the film pressing wheel, causing the film pressing wheel to stop rotating, which seriously affects the efficiency of sowing operations. In addition, the residual pollution of agricultural mulch film will also affect the growth and development of soil organisms. Earthworms are one of the animal groups with the largest biomass in the soil, accounting for 60% of the total soil animal biomass. Studies have shown that high concentrations of microplastic pollution can cause earthworms to have a significant avoidance reaction in a short period of time, and seriously reduce the growth rate of earthworms and inhibit the number of offspring hatching.

[0004] After more than 10 years of research, biodegradable plastic mulch (double-degradable mulch) is a type of plastic made by combining photodegradation and biodegradation. Although this type of degradation degrades the mulch into small particles, it will not have a significant negative impact on crop growth in the short term. However, as the use time increases, the plastic particles in the soil gradually increase, and the pollution and damage to the soil still exist, and the plastic particles cannot be removed. Summary of the invention

[0005] The purpose of the present invention is to provide a degradable organic fertilizer coated paper mulch film with high economic value and a method for manufacturing the paper mulch film.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] The invention provides an organic fertilizer coated paper ground film, comprising a stacked top coating layer, a core pulp and a bottom sizing layer, the coating adopts a film transfer method, and the coating amount is 3-8g / m 2 The top coating layer is mainly composed of starch, MFC nanocellulose, sodium humate, urea and carbon black. The core pulp is mainly composed of OCC slurry, and the bottom sizing layer is mainly composed of starch.

[0008] In one embodiment, the weight of the top coating layer is 2 g / m 2 -3g / m 2The core pulp weight is 40g / m 2 -120g / m 2 The weight of the bottom glue layer is 1g / m 2 -3g / m 2 .

[0009] In addition, the present invention also provides a method for preparing an organic fertilizer coated paper mulch film, which is used to prepare the above-mentioned organic fertilizer coated paper mulch film, comprising the following steps:

[0010] S1. Using waste paper to prepare core pulp through a papermaking process;

[0011] S2, coating and surface sizing the core pulp obtained in S1, forming a top coating layer and a bottom sizing layer on two surfaces of the core pulp, respectively, to form a base paper ground film;

[0012] S3, calendering / rolling the base paper ground film formed in S2 to obtain a finished paper ground film.

[0013] In one embodiment, S1, the step of preparing core pulp by using waste paper through a papermaking process specifically comprises the following steps:

[0014] S11, pulping: adding waste paper into a pulper for pulping to obtain a high-concentration pulp;

[0015] S12, remove impurities: remove impurities in high-concentration slurry;

[0016] S13, beating and storing: sending the pulp obtained after removing impurities in S12 to a high-consistency refiner for beating, and storing the pulp after beating in a pulping tower;

[0017] S14, sizing in the pulping tank: adding AKD and aluminum sulfate in the pulping tank to sizing the slurry of S13;

[0018] S15, flow conveying system: dilute the slurry of S14 to obtain a slurry with a concentration of 0.5%-1.0%, and add a wet strength agent and a dry strength agent;

[0019] S16, forming: the slurry sent from S15 is formed and dehydrated through a forming net to increase the slurry concentration from 0.5%-1.0% to 20%-25%;

[0020] S17, pressing: pressing the slurry from S16 to increase its concentration from 20%-25% to 46%-55%;

[0021] S18, drying: drying the pulp squeezed in S17, increasing the pulp concentration from 46%-55% to 90%-95% to form core pulp.

[0022] In one embodiment, S12, the step of removing impurities specifically includes the following steps:

[0023] S121, high-concentration sand removal: the high-concentration slurry in S11 is put into a high-concentration sand remover to remove heavy impurities, mainly metals, in the high-concentration slurry to obtain a low-concentration slurry;

[0024] S122, coarse screening: putting the low-concentration slurry prepared in S121 into a coarse screening pressure screen for screening to separate larger impurities and obtain coarse screening slurry;

[0025] S123, low-concentration sand removal: the coarse-screened slurry prepared in S122 is put into a low-concentration heavy-mass remover to remove other heavy impurities, mainly sand particles, in the coarse-screened slurry to obtain a sand-removed slurry;

[0026] S124, fine screening: putting the sand-removed mortar prepared in S123 into a fine screening pressure screen for screening to remove fine impurities in the slurry and obtain clean slurry;

[0027] S125, multi-disc concentration: the clean slurry obtained in S124 is put into a multi-disc concentrator for concentration to obtain a concentrated slurry.

[0028] In one embodiment, the step of removing impurities further includes the following steps: S126, thermal dispersion: performing thermal dispersion treatment on the concentrated slurry of S125 to refine the hot melt in the slurry.

[0029] The beneficial effects brought by the technical solution provided by the present invention are:

[0030] 1. The main raw materials of the organic fertilizer coated paper mulch of the present invention are starch, MFC type nanocellulose, sodium humate, urea and OCC slurry, which can be degraded by microorganisms in the soil after a certain period of use without causing pollution. 98% of the decomposed products are natural single plant fibers, and 0-2% are nitrogen fertilizers, which can be absorbed by crops and provide nutrients for crops, reducing the use of chemical fertilizers and having high economic value.

[0031] 2. The paper mulch is made of 100% recycled natural organic fibers (such as old corrugated cardboard boxes) and can be preserved for a long time.

[0032] 3. The organic fertilizer coating is a black coating that uses advanced and unique technology to produce natural organic fertilizer compounded with nanofibers. It has the functions of slow release, heat preservation and water retention. It also has the functions of improving soil fertility and soil repair, which is beneficial to the repair of saline-alkali land or polluted land.

[0033] 4. Using paper instead of plastic and making full use of recycled fibers not only reduces land pollution, but also reduces the cost of recycling and processing plastics.

[0034] 5. The paper mulch produced by the present invention has a certain thickness, is light-proof and opaque, and can inhibit the growth of weeds after covering. Not using herbicides not only reduces the cost of herbicides, but also improves the ecological environment and food safety, and is the best choice for organic production.

[0035] 6. The paper mulch produced by the present invention has a certain thickness and has good functions of heat preservation, breathability, water absorption and moisture absorption. It can be used for planting in early spring or cold areas, inhibiting the sharp rise in soil temperature during the day in summer, and is breathable and ventilated to prevent condensation and seedling burning.

[0036] 7. The use of paper mulch in rice planting has good weed control effect, can increase water temperature, promote rice development, and shorten the maturity period. It is the preferred mulch for organic rice. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for describing the embodiments of the present invention are briefly introduced below.

[0038] Figure 1 A generalized flow chart of a method for manufacturing an organic fertilizer coated paper mulch film provided by one embodiment of the present invention;

[0039] Figure 2 A detailed flow chart of a method for manufacturing an organic fertilizer coated paper mulch film provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0040] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0041] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0042] The term "including" and its variations used herein are open inclusions, i.e., "including but not limited to". The term "connected" may be directly connected or indirectly connected through intermediate components (elements). The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0043] The present invention provides an organic fertilizer coated paper mulch film (hereinafter referred to as "paper mulch film"), which is used for laying on the soil surface during agricultural production to provide functions of heat preservation, shading and inhibiting weed growth.

[0044] The paper ground film comprises a stacked top coating layer, a core pulp and a bottom sizing layer, wherein the top coating layer is mainly composed of starch, MFC nanocellulose, sodium humate and urea in the ratio of 10%-30%: 10%-30%: 30%-50%: 10%-30%, the core pulp is mainly composed of OCC pulp, and the bottom sizing layer is mainly composed of starch. Among them, OCC pulp refers to pulp obtained after deinking of old corrugated containers (OCC).

[0045] In one embodiment, the weight of the top coating layer is 2 g / m 2 -3g / m 2 The core pulp weight is 40g / m 2 -120g / m 2 The weight of the bottom glue layer is 1g / m 2 -3g / m 2 .

[0046] Wherein, the top coating layer contains a variety of oxygen-containing functional groups. Preferably, the oxygen-containing functional groups include carboxyl, alcoholic hydroxyl, phenolic hydroxyl and the like.

[0047] The organic fertilizer coated paper mulch film of the present invention has the following characteristics:

[0048] 1. The main raw materials of the organic fertilizer coated paper mulch of the present invention are starch, MFC type nanocellulose, sodium humate, urea and OCC slurry, which can be degraded by microorganisms in the soil after a certain period of use without causing pollution. 98% of the decomposed products are natural single plant fibers, and 0-2% are nitrogen fertilizers (wherein humic acid is a mixture rich in natural macromolecular aromatics, hydroxyls, and carboxyls, and the main elements are carbon, hydrogen, oxygen, nitrogen and sulfur, and the nitrogen content is usually about 1%. The nitrogen content of urea is 46%.), which increases the nitrogen content in the soil, is absorbed by crops and provides nutrients for crops, reduces the use of chemical fertilizers, and has high economic value.

[0049] 2. The organic fertilizer coated paper mulch is produced from 100% recycled natural organic fibers (such as old corrugated paper boxes) and can be preserved for a long time.

[0050] 3. The organic fertilizer coating is a black coating, which is a natural organic fertilizer composited with nanofibers using an advanced and unique process. The coating contains various oxygen-containing functional groups such as carboxyl, alcohol hydroxyl, phenolic hydroxyl, etc. It has acidity, water-soaking properties, and cation exchange properties. It can adsorb, exchange ions, complex and redox with pollutants in the soil, thereby repairing and improving the degraded soil, which is beneficial to the restoration of saline-alkali land or contaminated land.

[0051] 4. Using paper instead of plastic and making full use of recycled fibers not only reduces pollution, but also reduces the cost of recycling and processing plastics.

[0052] 5. The organic fertilizer coated paper mulch produced by the present invention has a certain thickness, is light-proof and opaque, and can inhibit the growth of weeds after covering. Not using herbicides not only reduces the cost of herbicides, but also improves the ecological environment and food safety, and is the best choice for organic production.

[0053] 6. The organic fertilizer coated paper mulch produced by the present invention has a certain thickness and has good functions of heat preservation, breathability, water absorption and moisture absorption. It can be used for planting in early spring or cold areas, inhibiting the sharp rise in soil temperature during the day in summer, and is breathable and ventilated to prevent condensation and seedling burning.

[0054] 7. The use of paper mulch in rice planting has good weed control effect, can increase water temperature, promote rice development, and shorten the maturity period. It is the preferred mulch for organic rice.

[0055] In addition, please combine Figure 1 and Figure 2 The present invention also provides a method for preparing an organic fertilizer coated paper mulch film, which is used to prepare the above-mentioned organic fertilizer coated paper mulch film, comprising the following steps:

[0056] S1. Use waste paper to prepare core pulp through a papermaking process.

[0057] The waste paper (mainly composed of natural organic fibers) is, for example, old corrugated paper boxes, which are de-inked to form OCC raw materials, and the core pulp is manufactured by using the OCC raw materials through a papermaking process.

[0058] S2. The core pulp obtained in S1 is coated and surface sized to form a top coating layer and a bottom sizing layer on two surfaces of the core pulp, respectively, so that the paper sheet has specific functions and forms a base paper film.

[0059] S3, calendering / rolling the base paper ground film formed in S2 to obtain a finished paper ground film.

[0060] In one embodiment, step S1 specifically includes the following steps:

[0061] S11. Pulping: Add waste paper (i.e. OCC raw material) into a pulper for pulping to obtain a high-concentration pulp.

[0062] S12. Remove impurities: remove impurities in high-concentration slurry.

[0063] S13, beating and storing: the pulp obtained after removing impurities in S12 is sent to a high-consistency refiner for beating, and the pulp after beating is stored in a pulping tower. The beating by the high-consistency refiner improves the degree of fiber hydrogen bonding, thereby improving the physical strength of the paper sheet.

[0064] S14, sizing in the pulping tank: AKD and aluminum sulfate are added in the pulping tank to sizing the S13 pulp to improve the water resistance of the pulp, so that the water resistance of the final paper mulch is improved.

[0065] S15, flow conveying system: dilute the pulp of S14 to obtain a pulp with a concentration of 0.5%-1.0%, and add chemicals such as wet strength agent and dry strength agent to improve the physical strength of the paper sheet.

[0066] S16, forming: the slurry sent from S15 is formed and dehydrated through a forming net to increase the slurry concentration from 0.5%-1.0% to 20-25%;

[0067] S17, pressing: pressing the slurry from S16 to increase its concentration from 20%-25% to 46%-55%.

[0068] S18, drying: drying the pulp squeezed in S17, increasing the pulp concentration from 46%-55% to 90%-95% to form core pulp.

[0069] In one embodiment, S12, the step of removing impurities specifically includes the following steps:

[0070] S121, high-concentration sand removal: the high-concentration slurry in S11 is put into a high-concentration sand remover to remove heavy impurities, mainly metals, in the high-concentration slurry to obtain a low-concentration slurry;

[0071] S122, coarse screening: putting the low-concentration slurry prepared in S121 into a coarse screening pressure screen for screening to separate larger impurities and obtain coarse screening slurry;

[0072] S123, low-concentration sand removal: the coarse-screened slurry prepared in S122 is put into a low-concentration heavy-mass remover to remove other heavy impurities, mainly sand particles, in the coarse-screened slurry to obtain a sand-removed slurry;

[0073] S124, fine screening: putting the sand-removed mortar prepared in S123 into a fine screening pressure screen for screening to remove fine impurities in the slurry and obtain clean slurry;

[0074] S125, multi-disc concentration: the clean slurry obtained in S124 is put into a multi-disc concentrator for concentration to obtain a concentrated slurry.

[0075] In one embodiment, S12, the step of removing impurities also includes the following steps: S126, thermal dispersion: performing thermal dispersion treatment on the concentrated slurry of S125 to refine the oil wax substances and other hot melts in the slurry to obtain a purer slurry.

[0076] The main technical indicators of using recycled boxboard to produce pulp with impurities removed according to the above process and making organic fertilizer coated paper mulch on a high-speed fourdrinier paper machine are as follows:

[0077] 1. Basis weight of base paper: 45g / m 2 –120g / m 2 ;

[0078] 2. Tightness: <0.55-0.7g / cm 3 ;

[0079] 3. Burst resistance index: >1.4-5.0kPa.m 2 / g;

[0080] 4. Tensile index: >10-75N.m / g;

[0081] 5. Water absorption (60 seconds): <20-40g / m 2

[0082] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0083] Example 1

[0084] This embodiment is mainly prepared by the following operations:

[0085] Weigh 400g of recycled pulp made of 13# US waste paperboard, add 300g of recycled pulp made of 11# and 12# US waste paperboard, and add 300g of domestic waste noodle paperboard, use a pulper to crush all the pulp boards into pulp at a concentration of 5%, then use a high-concentration desander and a pressure screen to remove impurities and stickies in turn, then use a fine screen and a low-concentration desander to further remove impurities in the pulp, finally use a multi-disc concentrator to concentrate the pulp, and reduce the pulp freeness to 350ml through disc heat dispersion and double-disc grinding, and pour the screened and ground pulp into a pulping tank.

[0086] After the obtained slurry is poured into the pulping tank, 6kg aluminum sulfate, 30g wet strength agent PAE, 10g sizing agent AKD, and 0.15g retention aid CPAM are added to the slurry in sequence. The mixed slurry passes through the pre-net pressure screen (to remove impurities) and enters the headbox (i.e., the flow conveying system) and enters the high-speed fourdrinier paper machine for forming. The net concentration is 1.2%, the paper machine speed is 1000m / min, and then it is pressed, with a line pressure of 100N / m 2 , second pressure line pressure 110N / m 2 , three-line pressure 1100N / m 2 , the dryness after pressing is 48-52%. Then it is dried, the pressure of the drying cylinder in the drying section is: 30-350kPa in the first stage; 40-400kPa in the second stage, the moisture content of the finished paper is 8%, the concentration of the organic coating storage tank is 30%, and the concentration of the working tank is 10%.

[0087] In addition, a method for preparing an organic fertilizer coating is also provided, which is specifically as follows (preparing 2000 ml of coating):

[0088] (1) 56 kg of corn starch was stirred at a concentration of 10% at room temperature using a disperser at a speed of 500 r / min for 30 minutes to uniformly disperse the starch.

[0089] (2) Add 986 ml of water, then slowly add 110 kg of absolute dry sodium humate, and continue stirring at 1000 r / min for 30 min.

[0090] (3) Add 38 kg of water and 4 kg of absolute dry MFC nanocellulose, and continue stirring at a speed of 2000 r / min for 30 minutes.

[0091] (4) Add 258 kg of water and 28 kg of urea, and continue stirring at 2000 r / min for 30 minutes.

[0092] (5) Add 2 kg of carbon black and continue stirring at 5000 r / min for 25 min to fully disperse the pigment.

[0093] The organic fertilizer coating is combined with the core pulp to form a top coating layer, and then a bottom sizing layer mainly made of starch is coated on the bottom of the core pulp layer to form the organic fertilizer coating paper mulch film of the present invention. Since coating the coating layer and sizing layer on the upper and lower surfaces of the core pulp layer is a mature process, it will not be described in detail here.

[0094] In the organic fertilizer coated paper mulch obtained in this embodiment, the weight of the top coating layer is 3-4 g / m 2 , the core pulp weight is 80g / m 2 The weight of the bottom glue layer is 1-3g / m 2 . The paper weight is 80g / m 2The mulch paper can be degraded in 2-4 months, and the nitrogen content in the soil increases by 0.2679g / m 2 .

[0095] Example 2

[0096] This embodiment is mainly prepared by the following operations:

[0097] Weigh 600g of recycled pulp made of 13# US waste cardboard, add 400g of recycled pulp made of 11#-12# US waste cardboard, use a pulper to crush all the pulp boards into pulp at a concentration of 5%, then use a high-concentration desander and a pressure screen to remove impurities and stickies in turn, then use a fine screen and a low-concentration desander to further remove impurities in the pulp, finally use a multi-disc concentrator to concentrate the pulp, and use disc heat dispersion and double-disc grinding to reduce the pulp freeness to 320ml, and pour the screened and ground pulp into a pulping tank.

[0098] The obtained slurry was poured into a pulping tank, and 6kg aluminum sulfate, 60g wet strength agent PAE, 30g AKD, and 0.30g retention aid CPAM were added to the slurry in sequence. The mixed slurry was passed through a pre-net pressure screen (to remove impurities) and then into a headbox. The net concentration was 1.2%, the paper machine speed was 1000m / min, and the first pressure line pressure was 100N / m 2 , second pressure line pressure 110N / m 2 , three-line pressure 1100N / m 2 , the dryness after pressing is 48-52%. The pressure of the drying cylinder in the drying section: 30-350kPa in the first stage; 40-400kPa in the second stage, the moisture content of the finished paper is 8%, the concentration of the organic coating storage tank is 30%, and the concentration of the working tank is 10%.

[0099] In addition, a method for preparing an organic fertilizer coating is also provided, which is specifically as follows (preparing 2000 ml of coating):

[0100] (1) 56 kg of corn starch was stirred at a concentration of 10% at room temperature using a disperser at a speed of 500 r / min for 30 minutes to uniformly disperse the starch.

[0101] (2) Add 986 ml of water, then slowly add 110 kg of absolute dry sodium humate, and continue stirring at 1000 r / min for 30 min.

[0102] (3) Add 38 kg of water and 4 kg of absolute dry MFC nanocellulose, and continue stirring at a speed of 2000 r / min for 30 minutes.

[0103] (4) Add 258 kg of water and 28 kg of urea, and continue stirring at 2000 r / min for 30 minutes.

[0104] (5) Add 2 kg of carbon black and continue stirring at 5000 r / min for 25 min to fully disperse the pigment.

[0105] The organic fertilizer coating is combined with the core pulp to form a top coating layer, and then a bottom sizing layer mainly made of starch is coated on the bottom of the core pulp layer to form the organic fertilizer coating paper mulch film of the present invention. Since coating the coating layer and sizing layer on the upper and lower surfaces of the core pulp layer is a mature process, it will not be described in detail here.

[0106] In the organic fertilizer coated paper mulch provided in this embodiment, the weight of the top coating layer is 4 g / m 2 , the core pulp weight is 120g / m 2 The weight of the bottom glue layer is 1-3g / m 2 The paper weight is 120g / m 2 The mulch paper can be degraded in 6-8 months. After degradation, the nitrogen content in the soil increases by 0.2858g / m 2 .

[0107] Example 3

[0108] This embodiment is mainly prepared by the following operations:

[0109] Weigh 300g of recycled pulp made of 13# US waste cardboard, add 700g of recycled pulp made of 11#-12# US waste cardboard, use a pulper to crush all the pulp boards into pulp at a concentration of 5%, then use a high-concentration desander and a pressure screen to remove impurities and stickies in turn, then use a fine screen and a low-concentration desander to further remove impurities in the pulp, finally use a multi-disc concentrator to concentrate the pulp, and reduce the freeness of the pulp to 380ml through disc heat dispersion and double-disc grinding, and pour the screened and ground pulp into a pulping tank.

[0110] The obtained slurry was poured into a pulping tank, and 4kg aluminum sulfate, 10g PAE, 5g AKD, and 0.10g CPAM were added to the slurry in sequence. The mixed slurry was passed through a pre-net pressure screen (to remove impurities) and then into a headbox. The net concentration was 1.2%, the paper machine speed was 1000m / min, and the first pressure line pressure was 100N / m 2 , second pressure line pressure 110N / m 2 , three-line pressure 1100N / m 2 , the dryness after pressing is 48-52%. The pressure of the drying cylinder in the drying section: 30-350kPa in the first stage; 40-400kPa in the second stage, the moisture content of the finished paper is 8%, the concentration of the organic coating storage tank is 30%, and the concentration of the working tank is 10%.

[0111] In addition, a method for preparing an organic fertilizer coating is also provided, which is specifically as follows (preparing 2000 ml of coating):

[0112] (1) 56 kg of corn starch was stirred at a concentration of 10% at room temperature using a disperser at a speed of 500 r / min for 30 minutes to uniformly disperse the starch.

[0113] (2) Add 986 ml of water, then slowly add 110 kg of absolute dry sodium humate, and continue stirring at 1000 r / min for 30 min.

[0114] (3) Add 38 kg of water and 4 kg of absolute dry MFC nanocellulose, and continue stirring at a speed of 2000 r / min for 30 minutes.

[0115] (4) Add 258 kg of water and 28 kg of urea, and continue stirring at 2000 r / min for 30 minutes.

[0116] (5) Add 2 kg of carbon black and continue stirring at 5000 r / min for 25 min to fully disperse the pigment.

[0117] The organic fertilizer coating is combined with the core pulp to form a top coating layer, and then a bottom sizing layer mainly made of starch is coated on the bottom of the core pulp layer to form the organic fertilizer coating paper mulch film of the present invention. Since coating the coating layer and sizing layer on the upper and lower surfaces of the core pulp layer is a mature process, it will not be described in detail here.

[0118] The weight of the top coating layer is 2 g / m 2 , the core pulp weight is 60g / m 2 The weight of the bottom glue layer is 1-3g / m 2 The paper weight is 60g / m 2 The mulch paper can be degraded in 1-2 months. After degradation, the nitrogen content in the soil increases by 0.1429g / m 2 .

[0119] According to the above examples, the organic fertilizer coated paper mulch film of the present invention can meet the needs of agricultural production. The paper mulch film covering is gradually decomposed by microorganisms in the field and does not need to be collected. 2 The finished paper will be completely degraded in about 50-60 days, and the longest degradation time is 120g / m 2 It takes 180-240 days for the paper mulch to be made into paper. The paper mulch will rot and will not pollute the soil. It can be used for a variety of crops with different operation times. The products after the decomposition of the paper mulch can increase the nitrogen content of the soil, which can be absorbed by crops and provide nutrients for crops, reduce the use of chemical fertilizers, and provide a more economical and sustainable solution for agricultural production.

[0120] The above description is only a preferred embodiment of the present invention and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present invention is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above inventive concept. For example, the above features are replaced with the technical features with similar functions invented in the present invention (but not limited to) to form a technical solution.

[0121] Although the subject matter has been described in language specific to structural features and / or methodological logical actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. On the contrary, the specific features and actions described above are merely example forms of implementing the claims.

Claims

1. An organic fertilizer coated paper mulch film, comprising a top coating layer, a core pulp and a bottom sizing layer stacked in layers, characterized in that: The top coating layer is mainly composed of starch, MFC type nanocellulose, sodium humate and urea in the percentages of 10%-30%: 10%-30%: 30%-50%: 10%-30%, the core pulp is mainly composed of OCC pulp, and the bottom sizing layer is mainly composed of starch.

2. The organic fertilizer coated paper mulch film according to claim 1, characterized in that: The weight of the top coating layer is 2 g / m 2 -3g / m 2 The core pulp weight is 40g / m 2 -120g / m 2 The weight of the bottom glue layer is 1g / m 2 -3g / m 2 .

3. The organic fertilizer coated paper mulch film according to claim 1, characterized in that: The topcoat layer contains a variety of oxygen-containing functional groups.

4. The organic fertilizer coated paper mulch film according to claim 3, characterized in that: The oxygen-containing functional groups include carboxyl, alcoholic hydroxyl and phenolic hydroxyl.

5. A method for manufacturing an organic fertilizer coated paper mulch film, characterized in that: The method for preparing the organic fertilizer coated paper mulch film according to any one of claims 1 to 4 comprises the following steps: S1. Using waste paper to prepare core pulp through a papermaking process; S2, coating and surface sizing the core pulp obtained in S1, forming a top coating layer and a bottom sizing layer on two surfaces of the core pulp, respectively, to form a base paper ground film; S3, calendering / rolling the base paper ground film formed in S2 to obtain a finished paper ground film.

6. The method for manufacturing the organic fertilizer coated paper mulch film according to claim 5, characterized in that: S1. The step of preparing core pulp by using waste paper through a papermaking process specifically comprises the following steps: S11, pulping: adding waste paper into a pulper for pulping to obtain a high-concentration pulp; S12, remove impurities: remove impurities in high-concentration slurry; S13, beating and storing: sending the pulp obtained after removing impurities in S12 to a high-consistency refiner for beating, and storing the pulp after beating in a pulping tower; S14, sizing in the pulping tank: adding AKD and aluminum sulfate in the pulping tank to sizing the slurry of S13; S15, flow conveying system: dilute the slurry of S14 to obtain a slurry with a concentration of 0.5%-1.0%, and add a wet strength agent and a dry strength agent; S16, forming: the slurry sent from S15 is formed and dehydrated through a forming net to increase the slurry concentration from 0.5%-1.0% to 20%-25%; S17, pressing: pressing the slurry from S16 to increase its concentration from 20%-25% to 46%-55%; S18, drying: drying the pulp squeezed in S17, increasing the pulp concentration from 46%-55% to 90%-95% to form core pulp.

7. The method for manufacturing the organic fertilizer coated paper mulch film according to claim 6, characterized in that: S12, the step of removing impurities specifically includes the following steps: S121, high-concentration sand removal: the high-concentration slurry in S11 is put into a high-concentration sand remover to remove heavy impurities, mainly metals, in the high-concentration slurry to obtain a low-concentration slurry; S122, coarse screening: putting the low-concentration slurry prepared in S121 into a coarse screening pressure screen for screening to separate larger impurities and obtain coarse screening slurry; S123, low-concentration sand removal: the coarse-screened slurry prepared in S122 is put into a low-concentration heavy-mass remover to remove other heavy impurities, mainly sand particles, in the coarse-screened slurry to obtain a sand-removed slurry; S124, fine screening: putting the sand-removed mortar prepared in S123 into a fine screening pressure screen for screening to remove fine impurities in the slurry and obtain clean slurry; S125, multi-disc concentration: the clean slurry obtained in S124 is put into a multi-disc concentrator for concentration to obtain a concentrated slurry.

8. The method for manufacturing organic fertilizer coated paper mulch film according to claim 7, characterized in that: The step of removing impurities also includes the following steps: S126, thermal dispersion: The concentrated slurry of S125 is subjected to thermal dispersion treatment to refine the hot melt in the slurry.

9. The method for manufacturing organic fertilizer coated paper mulch film according to claim 6, characterized in that: In S16, the forming step, the slurry delivered from S15 is formed by a forming net.

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