Degradable white mulching film paper suitable for greenhouse planting and preparation method thereof
By preparing recycled fiber mulch paper, the problems of insufficient strength of white plastic mulch film and high cost of degradable mulch film are solved, and high strength and degradable mulch paper are achieved, reducing production costs and reducing environmental pollution.
Patent Information
- Application Number
- CN202510683567.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-26
- Publication Date
- 2025-07-18
AI Technical Summary
The existing white plastic plastic film has problems such as low dry and wet strength and no elasticity in greenhouse planting, which leads to damage and pollute the environment. At the same time, the degradable plastic film has high cost and poor functionality, making it difficult to promote.
The surface layer, core layer and bottom layer are prepared by recycled fibers. Through the pulping and bleaching process and in-pulp glue application technology, the preparation process includes pulping, impurity removal, bleaching, concentration, composite and drying steps to form a plastic film with high strength and degradability.
It realizes the high strength and degradability of mulch paper, reduces production costs, and can be naturally decomposed after use, does not pollute the soil, and has the functions of avoiding light, insulation, breathable and water absorption, reducing environmental pollution.
Smart Images
Figure CN120331072A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of the preparation technology of plastic mulch paper, in particular to a degradable white plastic mulch paper applicable to greenhouse planting and a preparation method thereof. Background Art
[0002] Agricultural plastic films (referred to as agricultural mulches for short) have been widely used in the past, but the long-term and large-scale use of agricultural mulches and the lack of effective recycling and treatment have led to the aggravation of "white pollution". Therefore, degradable mulch films have become a research hotspot.
[0003] The white plastic mulch films currently widely used in grape planting have a fast heating rate and a large heating range, but weeds are likely to grow inside the film. If the branches and vines do not block the ground enough in the middle period, the soil temperature inside the film may be too high, causing damage to the roots. This white mulch film is mainly a polyethylene mulch film. First of all, it is very difficult to recycle polyethylene mulch film 100%. The mulch film fragments cannot be degraded by soil microorganisms and cannot be absorbed and utilized by crops, causing serious soil pollution. Secondly, although there are already some degradable plastic mulch films, their dry and wet strengths are not high, they have no stretchability, and they cannot effectively reduce the environmental problems caused by mulch film breakage. Thirdly, the existing degradable paper mulch films currently have a high cost and poor functionality, and it is difficult to be widely promoted. Summary of the Invention
[0004] In order to improve the problem of environmental pollution caused by the breakage of plastic mulch films due to their low dry and wet strengths and lack of stretchability, and at the same time increase the degradation rate of white plastic mulch paper and reduce its production cost, the present application provides a degradable white plastic mulch paper applicable to greenhouse planting and a preparation method thereof.
[0005] A degradable white plastic mulch paper applicable to greenhouse planting and a preparation method thereof provided by the present application adopt the following technical solutions:
[0006] A degradable white plastic mulch paper applicable to greenhouse planting includes a surface layer, a core layer and a bottom layer. The surface layer is white recycled fiber, and both the core layer and the bottom layer are natural color recycled fiber.
[0007] A preparation method of a degradable white plastic mulch paper applicable to greenhouse planting includes:
[0008] S1. Prepare the surface layer pulp by using recycled office waste paper fiber through a pulping, bleaching and papermaking process;
[0009] S2. Prepare the core layer and bottom layer pulp by using recycled natural color corrugated paper fiber through a pulping and papermaking process;
[0010] S3. Apply internal sizing to the surface layer, core layer and bottom layer pulp obtained in S1 and S2, then enter a high-speed paper machine for compounding, pressing in the wet part, then enter the dryer section for drying, coating, supercalendering, and rewinding to produce finished products.
[0011] Preferably, the specific steps of preparing the surface layer pulp by using recycled office waste paper fibers through the pulping, bleaching and papermaking process in S1 are as follows:
[0012] S11. Pulping: Add office waste paper into a drum pulper for pulping to obtain high-concentration pulp.
[0013] S12. Removing impurities: Remove impurities in the high-concentration pulp.
[0014] S13. Flotation and low-concentration sand removal: Feed the pulp obtained after removing impurities in S12 into a flotation cell to remove impurities such as ink adhesives in the pulp.
[0015] S14. Low-concentration sand removal: Put the flotation pulp obtained in S13 into a low-concentration heavy-duty slag remover to remove other heavy impurities mainly composed of sand grains in the pulp and obtain de-slagged pulp.
[0016] S15. Fine screening: Put the de-slagged pulp obtained in S14 into a fine screening pressure screen for screening to remove fine impurities in the pulp and obtain clean pulp.
[0017] S16. Multi-tray concentration: Put the clean pulp obtained in S15 into a multi-tray concentrator for concentration to obtain concentrated pulp, and perform heat dispersion treatment on the concentrated pulp to refine the hot melts in the pulp.
[0018] S17. Oxidative bleaching: Perform hydrogen peroxide oxidative bleaching on the pulp obtained in S16.
[0019] S18. Reductive bleaching: After the pulp after oxidative bleaching in S17 is subjected to flotation and multi-tray concentration again, it enters a reductive bleaching tower.
[0020] S19. Transport to the surface layer stock tank: Transport the pulp after reductive bleaching in S18 to the surface layer stock tank.
[0021] Preferably, the specific steps of preparing the core layer and bottom layer pulp by using recycled natural box board paper fibers through the pulping and papermaking process in S2 are as follows:
[0022] S21. Pulping: Add recycled box board waste paper into a low-concentration vertical pulper for pulping to obtain high-concentration pulp.
[0023] S22. High-concentration sand removal: Put the high-concentration pulp in S21 into a high-concentration sand remover to remove heavy impurities mainly composed of metal in the high-concentration pulp and obtain low-concentration pulp.
[0024] S23. Coarse screening: Put the low-concentration pulp obtained in S22 into a coarse screening pressure screen for screening to separate large-sized impurities and obtain coarsely screened pulp.
[0025] S24, Low-concentration sand removal: Feed the coarsely screened pulp obtained in S23 into a low-concentration heavy impurity remover to remove other heavy impurities mainly composed of sand grains in the coarsely screened pulp, and obtain de-sanded pulp.
[0026] S25, Fine screening: Feed the de-sanded pulp obtained in S24 into a fine screening pressure screen for screening to remove fine impurities in the pulp, and obtain clean pulp.
[0027] S26, Multi-tray concentration: Feed the clean pulp obtained in S25 into a multi-tray concentrator for concentration to obtain concentrated pulp, and transport the concentrated pulp to the core layer and bottom layer forming pulp towers.
[0028] Preferably, the specific steps of sizing the surface layer, core layer, and bottom layer pulp obtained in S1 and S2 in S3, then entering a high-speed paper machine for wet-end lamination, pressing, then entering the dryer section for drying, coating, supercalendering, and rewinding to produce finished products are as follows:
[0029] S31, Dehydration and lamination: In the forming step, the pulp sent from S1 and S2 is formed, dehydrated, and laminated through the surface, core, and bottom forming meshes, increasing the pulp concentration from 0.5% - 1.0% to 20% - 25%.
[0030] S32, Pressing: Press the pulp from S31 to increase its concentration from 20% - 25% to 46% - 55%.
[0031] S33, Drying: Dry the pressed pulp from S32, increasing the pulp concentration from 46% - 55% to 90% - 95%.
[0032] S34, Finished product: Supercalender and rewind to produce finished products.
[0033] In summary, the present application includes the following beneficial technical effects:
[0034] 1. The present invention uses paper mulch films to produce organic crops. Natural fibers have functions such as light shielding, opacity, heat preservation, air permeability, water absorption, and moisture absorption, and do not require pesticides or herbicides.
[0035] 2. The surface layer of the paper mulch film in the present invention is white recycled fiber (white has good heat preservation and a reflective effect that can promote the early ripening of grapes), and the core layer and bottom layer are natural-colored recycled fibers (with light shielding, weed control, and heat preservation effects).
[0036] 3. The present invention replaces plastics with paper, makes full use of recycled fibers, uses a production process with low comprehensive energy consumption, creates a new high-value-added paper-based material with a low carbon footprint, and plows it into the soil after harvesting. It will be naturally decomposed by microorganisms in the soil, and at the same time achieve the purpose of loosening the soil without causing pollution to the soil. Brief Description of the Drawings
[0037] Figure 1 It is a schematic flow chart of a degradable white plastic film paper applicable to greenhouse planting and its preparation method in the embodiments of the present application. Specific embodiments
[0038] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the solution in the embodiments of the present invention with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.
[0039] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation and specific orientation structure and operation. Therefore, it should not be construed as a limitation of the present invention; the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. In addition, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0040] The embodiments of the present application disclose a degradable white plastic film paper applicable to greenhouse planting and its preparation method. A degradable white plastic film paper applicable to greenhouse planting includes a surface layer, a core layer and a bottom layer. The surface layer is white recycled fiber, and both the core layer and the bottom layer are natural recycled fiber.
[0041] Referring to Figure 1 , a preparation method of a degradable white plastic film paper applicable to greenhouse planting includes:
[0042] S1. Prepare the surface layer pulp by using recycled office waste paper fiber through the pulping, bleaching and papermaking process;
[0043] S2. Prepare the core layer and the bottom layer pulp by using recycled natural corrugated paper fiber through the pulping and papermaking process;
[0044] S3. Apply internal sizing to the surface layer, core layer, and bottom layer pulp obtained in S1 and S2, then enter a high-speed paper machine for lamination, pressing, drying in the dryer section, coating, supercalendering, and reeling to produce the finished product.
[0045] Among them, the specific steps for preparing the surface layer pulp by using recycled office waste paper fibers through the pulping, bleaching, and papermaking process in S1 are as follows:
[0046] S11. Pulping: Add office waste paper into a drum pulper for pulping to obtain high-consistency pulp.
[0047] S12. Removing impurities: Remove impurities in the high-consistency pulp.
[0048] S13. Flotation and low-consistency sand removal: Feed the pulp obtained after removing impurities in S12 into a flotation cell to remove impurities such as ink adhesives in the pulp.
[0049] S14. Low-consistency sand removal: Feed the flotation pulp obtained in S13 into a low-consistency heavy-duty slag remover to remove other heavy impurities mainly composed of sand grains in the pulp and obtain de-slagged pulp.
[0050] S15. Fine screening: Feed the de-slagged pulp obtained in S14 into a fine screening pressure screen for screening to remove fine impurities in the pulp and obtain clean pulp.
[0051] S16. Multi-tray concentration: Feed the clean pulp obtained in S15 into a multi-tray concentrator for concentration to obtain concentrated pulp, and perform thermal dispersion treatment on the concentrated pulp to refine the hot melts in the pulp.
[0052] S17. Oxidative bleaching: Perform hydrogen peroxide oxidative bleaching on the pulp obtained in S16.
[0053] S18. Reductive bleaching: After the pulp obtained by oxidative bleaching in S17 undergoes flotation and multi-tray concentration again, enter the reductive bleaching tower.
[0054] S19. Transport to the surface layer stock tank: Transport the pulp obtained by reductive bleaching in S18 to the surface layer stock tank.
[0055] The specific steps for preparing the core layer and bottom layer pulp by using recycled unbleached corrugated paper fibers through the pulping and papermaking process in S2 are as follows:
[0056] S21. Pulping: Add recycled corrugated waste paper into a low-consistency vertical pulper for pulping to obtain high-consistency pulp.
[0057] S22. High-consistency sand removal: Feed the high-consistency pulp in S21 into a high-consistency sand remover to remove heavy impurities mainly composed of metal in the high-consistency pulp and obtain low-consistency pulp.
[0058] S23. Coarse screening: The low-concentration pulp obtained in S22 is put into a coarse screening pressure screen for screening to separate large-sized impurities and obtain coarse-screened pulp;
[0059] S24. Low-concentration sand removal: The coarse-screened pulp obtained in S23 is put into a low-concentration heavy impurity remover to remove other heavy impurities mainly composed of sand grains in the coarse-screened pulp and obtain sand-removed pulp;
[0060] S25. Fine screening: The sand-removed pulp obtained in S24 is put into a fine screening pressure screen for screening to remove fine-sized impurities in the pulp and obtain clean pulp;
[0061] S26. Multi-tray concentration: The clean pulp obtained in S25 is put into a multi-tray concentrator for concentration to obtain concentrated pulp, and the concentrated pulp is transported to the core layer and bottom layer forming pulp towers.
[0062] In S3, the surface layer, core layer, and bottom layer pulp obtained from S1 and S2 are subjected to in-pulp sizing, then enter a high-speed paper machine for wet part lamination, pressing, and then enter the dryer section for drying, coating, supercalendering, and rewinding to produce finished products. The specific steps are as follows:
[0063] S31. Dehydration and lamination: In the forming step, the pulp sent from S1 and S2 is formed, dehydrated, and laminated through the surface, core, and bottom forming meshes, and the pulp concentration is increased from 0.5% - 1.0% to 20% - 25%;
[0064] S32. Pressing: Press the pulp from S31 to increase its concentration from 20% - 25% to 46% - 55%;
[0065] S33. Drying: The pulp after pressing in S32 is dried, and the pulp concentration is increased from 46% - 55% to 90% - 95%;
[0066] S34. Finished product: Supercalendering and rewinding to produce finished products.
[0067] Example 1
[0068] The purpose of this example is to provide a single-sided white plastic mulch paper with a quantitative degradability of 100 g / m2 in 2 - 4 months, which is mainly prepared through the following operations:
[0069] 1) Weigh 40 g of office waste paper, shred it into pulp at a concentration of 5% using a pulper, then successively use a high - consistency sand remover and a pressure screen to remove impurities and adhesives. After that, pass it through a fine screen and a low - consistency sand remover to further remove impurities in the pulp. Finally, use a multi - disk concentrator to concentrate the pulp to a concentration of 40%, heat it to 85°C, and successively add 0.1% EDTA, 3% sodium silicate, 2.5% sodium hydroxide, and 3% hydrogen peroxide. After stirring with a spiral agitator, carry out an oxidative bleaching reaction for 1 hour. Dilute the oxidatively bleached pulp to a concentration of 1% and then carry out flotation, and multi - disk concentrate it to a concentration of 10%. Add 1% FAS at 75°C for reductive bleaching for 1 hour. Control the whiteness after bleaching at 70 - 75%. Wash the bleached pulp and send it to the surface - layer bleaching and pulp - making tank.
[0070] 2) Weigh 60 g of recycled pulp board made from 13# US waste paper board, shred all the pulp board into pulp at a concentration of 5% using a pulper, then successively use a high - consistency sand remover and a pressure screen to remove impurities and adhesives. After that, pass it through a fine screen and a low - consistency sand remover to further remove impurities in the pulp. Finally, use a multi - disk concentrator to concentrate the pulp, and reduce the freeness of the pulp to 350 ml through disk - type thermal dispersion and double - disk refining. Pour the well - screened and well - refined pulp into the core - layer and bottom - layer pulp - making tanks.
[0071] 3) Pour the pulp obtained from each layer into a pulp - mixing tank, at a basis weight of 100 g / m2 (where the surface layer is 40 g / m2, the core layer is 30 g / m2, and the bottom layer is 30 g / m2), and successively add 6 kg of aluminum sulfate, 30 g of PAE, 10 g of AKD, and 0.15 g of retention aid CPAM in the pulp. Pass the mixed pulp through a head - box pressure screen (to remove impurities) and into the head - box. The forming concentration is 1.2%, the paper machine speed is 1000 m / min, the first press nip pressure is 100 N / m2, the second press nip pressure is 110 N / m2, the third press nip pressure is 1100 N / m2, the dryness after pressing is 48 - 52%, the pressure of the drying section entering the dryer cylinder: the first stage is 30 - 350 kPa, the second stage is 40 - 400 kPa, the moisture content of the formed paper is 8%, the calendering line pressure of the super - calender is 40 N / m2, and after rewinding, produce a single - sided white plastic mulch paper with a basis weight of 100 g / m2.
[0072] Example 2
[0073] The purpose of this example is to provide a single - sided white plastic mulch paper that can be degraded within 3 - 6 months and has a basis weight of 125 g / m2, which is mainly prepared through the following operations:
[0074] 1) Weigh 45 g of office waste paper, break it into pulp at a concentration of 5% using a pulper, then successively use a high-consistency sand remover and a pressure screen to remove impurities and adhesives. After that, pass it through a fine screen and a low-consistency sand remover to further remove impurities in the pulp. Finally, use a multi-disk concentrator to concentrate the pulp to a concentration of 40%, heat it to 85 °C, and successively add 0.1% EDTA, 3% sodium silicate, 2.5% sodium hydroxide, and 3% hydrogen peroxide. After stirring with a spiral agitator, carry out an oxidative bleaching reaction for 1 hour. Dilute the oxidized and bleached pulp to a concentration of 1% and then carry out flotation. Concentrate it to a concentration of 10% with a multi-disk concentrator, add 1% FAS at 75 °C for reductive bleaching for 1 hour, control the brightness after bleaching at 70 - 75%, and send the bleached pulp to the surface layer bleaching and pulp making tank after washing.
[0075] 2) Weigh 80 g of recycled pulp board made from 13# US waste paper board, break all the pulp boards into pulp at a concentration of 5% using a pulper, then successively use a high-consistency sand remover and a pressure screen to remove impurities and adhesives. After that, pass it through a fine screen and a low-consistency sand remover to further remove impurities in the pulp. Finally, use a multi-disk concentrator to concentrate the pulp, reduce the freeness of the pulp to 350 ml through disk thermal dispersion and double disk refining, and pour the well-screened and well-refined pulp into the core layer and bottom layer pulp making tanks.
[0076] 3) Pour the pulp obtained from each layer into a pulp mixing tank, at a basis weight of 125 g / m² (where the surface layer is 45 g / m², the core layer is 40 g / m², and the bottom layer is 40 g / m²), and successively add 6 kg of aluminum sulfate, 30 g of PAE, 10 g of AKD, and 0.15 g of retention aid CPAM in the pulp. Pass the mixed pulp through a headbox pressure screen (to remove impurities) and into the headbox. The forming consistency is 1.2%, the paper machine speed is 1000 m / min, the first press nip pressure is 100 N / m², the second press nip pressure is 110 N / m², the third press nip pressure is 1100 N / m², the dryness after pressing is 48 - 52%, the pressure of the drying section entering the dryer cylinder: the first stage is 30 - 350 kPa, the second stage is 40 - 400 kPa, the moisture content of the formed paper is 8%, the supercalender nip pressure is 50 N / m², and after rewinding, produce a single-sided white plastic film paper with a basis weight of 125 g / m².
[0077] Finally, it should be noted that the above description is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements should also be regarded as within the protection scope of the present invention.
Claims
1. A degradable white plastic film paper suitable for greenhouse planting, characterized in that: It includes a surface layer, a core layer and a bottom layer. The surface layer is made of white recycled fibers, and both the core layer and the bottom layer are made of natural-color recycled fibers.
2. The preparation method of a degradable white plastic film paper applicable to greenhouse planting according to claim 1, characterized in that: It includes: S1. Prepare the surface layer pulp by using recycled office waste paper fibers through a pulping, bleaching and papermaking process; S2. Prepare the core layer and bottom layer pulp by using recycled natural-color corrugated paper fibers through a pulping and papermaking process; S3. Apply internal sizing to the surface layer, core layer and bottom layer pulp obtained in S1 and S2, then enter a high-speed paper machine for lamination, pressing at the wet end, and then enter the dryer section for drying, coating, supercalendering, and rewinding to obtain the finished product.
3. The preparation method of a degradable white plastic film paper applicable to greenhouse planting according to claim 2, characterized in that: The specific steps of preparing the surface layer pulp by using recycled office waste paper fibers through a pulping, bleaching and papermaking process in S1 are as follows: S11. Pulping: Add office waste paper into a drum pulper for pulping to obtain high-concentration pulp; S12. Remove impurities: Remove impurities in the high-concentration pulp; S13. Flotation and low-concentration sand removal: Feed the pulp obtained after removing impurities in S12 into a flotation cell to remove impurities such as ink adhesives in the pulp; S14. Low-concentration sand removal: Feed the flotation pulp obtained in S13 into a low-concentration heavy-duty slag remover to remove other heavy impurities mainly composed of sand grains in the pulp to obtain de-slagged pulp; S15. Fine screening: Feed the de-slagged pulp obtained in S14 into a fine screening pressure screen for screening to remove fine-sized impurities in the pulp to obtain clean pulp; S16. Multi-tray concentration: Feed the clean pulp obtained in S15 into a multi-tray concentrator for concentration to obtain concentrated pulp, and perform heat dispersion treatment on the concentrated pulp to refine the hot melts in the pulp; S17. Oxidative bleaching: Perform hydrogen peroxide oxidative bleaching on the pulp obtained in S16; S18. Reductive bleaching: After the pulp after oxidative bleaching in S17 undergoes flotation and multi-tray concentration again, enter a reductive bleaching tower; S19. Transport to the surface layer pulp tank: Transport the pulp after reductive bleaching in S18 to the surface layer pulp tank.
4. The preparation method of a degradable white plastic film paper applicable to greenhouse planting according to claim 2, characterized in that: The specific steps of preparing the core layer and bottom layer pulp by using recycled natural-color corrugated paper fibers through a pulping and papermaking process in S2 are as follows: S21. Pulping: Add recycled corrugated waste paper into a low-concentration vertical pulper for pulping to obtain high-concentration pulp; S22. High-concentration sand removal: Feed the high-concentration pulp in S21 into a high-concentration sand remover to remove heavy impurities mainly composed of metal in the high-concentration pulp to obtain low-concentration pulp; S23. Coarse screening: Feed the low-concentration pulp obtained in S22 into a coarse screening pressure screen for screening to separate large-sized impurities to obtain coarsely screened pulp; S24. Low-concentration sand removal: Feed the coarsely screened pulp obtained in S23 into a low-concentration heavy-duty slag remover to remove other heavy impurities mainly composed of sand grains in the coarsely screened pulp to obtain de-slagged pulp; S25. Fine screening: Feed the de-slagged pulp obtained in S24 into a fine screening pressure screen for screening to remove fine-sized impurities in the pulp to obtain clean pulp; S26. Multi-tray concentration: Feed the clean pulp obtained in S25 into a multi-tray concentrator for concentration to obtain concentrated pulp, and transport the concentrated pulp to the core layer and bottom layer pulp towers.
5. The preparation method of a degradable white plastic film paper applicable to greenhouse planting according to claim 2, characterized in that: In step S3, the surface layer, core layer, and bottom layer pulp obtained in S1 and S2 are sized in the pulp, and then enter a high-speed paper machine for composite, pressing in the wet part, and then enter the dryer section for drying, coating, supercalendering, and rewinding to produce the finished product. The specific steps are as follows: S31. Dehydration and composite: In the forming step, the pulp sent from S1 and S2 is formed, dehydrated, and composite through the surface, core, and bottom forming meshes, so that the pulp concentration is increased from 0.5%-1.0% to 20%-25%; S32. Pressing: Press the pulp from S31 to increase its concentration from 20%-25% to 46%-55%; S33. Drying: Dry the pressed pulp in S32, and the pulp concentration is increased from 46%-55% to 90%-95%; S34. Finished product: Supercalender and rewind to produce the finished product.