High-temperature edible oil filament nonwoven glueless filtration material and preparation method thereof

Abstract

The application discloses a kind of high-temperature edible oil filament nonwoven glueless filter material and preparation method thereof, based on spinning and air-laid technology, prepare PA6 / PBT bicomponent filament web, pulp fiber, PBT filament web sandwich structure of nonwoven filter material, filter material thickness is 0.6-1.5mm, grammage is 80-160gsm;The application guarantees the strength of filter material in structure, avoids the problem that hydrogen bond is invalid, fiber falls off and pollutes when glueless filter paper is used to treat large water content recycled edible oil, completely eliminates the problem of secondary pollution to filtered edible oil caused by fiber falling off;The processing technology of the application relies on heat bonding technology, overcomes the problem that general filter material is easily degraded at high temperature, and harmful components are separated out, and the high-temperature heat bonding process not only realizes material reinforcement, but also has significant high-temperature disinfection function, so that the filter material of the application meets the requirements of food-grade materials.

Description

TECHNICAL FIELD

[0001] The application relates to the field of edible oil filtration, in particular to a high-temperature edible oil filament non-woven glue-free filtration material and a preparation method thereof. BACKGROUND

[0002] With the continuous development of the food industry and the increasing demand of people for food safety and quality, the quality control of edible oil is becoming increasingly important. In the production and processing process of edible oil, especially in the high-temperature processing environment, the filtration link plays a key role in removing impurities and ensuring the purity and quality of edible oil.

[0003] The existing edible oil filtration materials mainly include metal filter screens and filter paper, and have the problems of low filtration precision, easy degradation of chemical binders in the filtration materials under high-temperature conditions, and release of harmful components, which pollute the edible oil and thus potentially threaten human health; and glue-free filtration materials are prone to hydrogen bond failure when encountering reused edible oil with high water content, resulting in fiber shedding of the filtration materials and secondary pollution of the filtered edible oil. SUMMARY

[0004] The purpose of the application is to provide a preparation method of a high-temperature edible oil filament non-woven glue-free filtration material to solve the problems in the background.

[0005] To achieve the above purpose, the application provides the following technical scheme:

[0006] A preparation method of a high-temperature edible oil filament non-woven glue-free filtration material, comprising the following steps:

[0007] 1) Low-melting-point PA6 chips and dried PBT chips are respectively melted, filtered and metered by a screw extruder, and then enter a spinning assembly to be spun into component A and component B;

[0008] 2) The component A and the component B are spun into a sheath-core type bi-component filament through the spinning assembly, wherein PA6 is used as the sheath layer and PBT is used as the core layer, and the mass ratio of PA6 is 10%-35%; then a narrow-slit drafting machine and a negative pressure suction fan are used to form a smooth PA6 / PBT filament web C with a grammage of 20-35gsm, and the PA6 / PBT filament web C enters an air-laid zone;

[0009] 3) The pulp fibers treated by the dry beating technology are added to the air-laid machine, the addition amount of the pulp fibers is 30-50gsm, the pulp fibers are deposited on the PA6 / PBT filament web C through the air-laid zone to form a composite web D, and then the composite web D is subjected to spray treatment, and the spray treatment is pure water mist spraying;

[0010] 4), the PBT chip after drying is melted by screw extruder, filtered, metered by metering pump, and then enters a spinning assembly to obtain PBT filaments, and the smooth PBT filament web is formed through a tubular drafting machine and a negative pressure suction fan, the web weight is 15-25gsm, and then is laid on the surface of the composite web D to form a sandwich structure;

[0011] 5), the composite web D is reinforced by hot air drying and light rolling drying, and a high-temperature edible oil filament non-woven glue-free filter material is obtained.

[0012] As a further scheme of the application, the bicomponent filament fineness in step 2 is 1.2D-3.5D, and the spinning speed is kept at 4000-5500m / min, and the single filament elongation at break is ≤85%.

[0013] As a further scheme of the application, the pure water mist spraying amount in step 3 is 20-50L / min.

[0014] As a further scheme of the application, the PBT filament diameter in step 4 is 1.5D-2.5D, and the overall thickness of the laid composite web D is controlled to be below 2mm.

[0015] As a further scheme of the application, the drying temperature in the hot air drying process in step 5 is kept at 160-200℃, the drying speed is kept at 15-25m / min, and the overall moisture content of the material after drying is controlled to be 3-5%.

[0016] As a further scheme of the application, the light rolling drying process in step 5 adopts three-roller rolling to dry and pretreat the composite web, wherein the 1-2# rolling distance is 0.3-1.1mm, the 2-3# pressure rolling adopts pressure rolling treatment, the pressure roller temperature is 120-160℃, the rolling pressure is 30-80N / mm, and the overall thickness of the material is not less than 1mm.

[0017] The application further provides a high-temperature edible oil filament non-woven glue-free filter material, which is prepared by the above preparation method, and has a material thickness of 0.6-1.5mm and a weight of 80-160gsm.

[0018] Compared with the prior art, the application has the following beneficial effects:

[0019] 1. This invention innovatively adopts a sandwich structure of PA6 / PBT filament web-pulp fiber-PBT filament web, which effectively ensures the strength of the filter material and avoids the problems of hydrogen bond failure and fiber shedding and contamination when non-adhesive filter paper is used to process recycled edible oil with high moisture content. At the same time, it can avoid damage caused by external force and fluid impact, achieve zero pulp fiber shedding, and completely eliminate the problem of secondary contamination of filtered edible oil caused by fiber shedding, thus effectively ensuring the purity and safety of the filtered product.

[0020] 2. The overall processing technology of this invention relies on thermal bonding technology, which overcomes the problem that chemical adhesives in general filter materials are prone to degradation and release harmful components at high temperatures. The minimum thermal bonding temperature of this invention is >120℃. This high-temperature thermal bonding process not only strengthens the material, but also has a significant high-temperature sterilization function, which can effectively kill bacteria and other microorganisms present on the filter material, so that the filter material of this invention meets the requirements of food-grade materials. Attached Figure Description

[0021] Figure 1 This is a flowchart of a method for preparing a high-temperature edible oil filament nonwoven adhesive-free filter material. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This application provides a high-temperature edible oil filament nonwoven adhesive-free filter material and its preparation method. The flowchart of the preparation method is shown below. Figure 1 As shown in the figure, the following describes the high-temperature edible oil filtration nonwoven material and its preparation method with reference to the embodiments.

[0024] A method for preparing a high-temperature edible oil filament nonwoven adhesive-free filter material involves first drying PBT chips to remove moisture, then melting them through a screw extruder, followed by filtration to remove impurities, and finally metering them with a metering pump before they enter the spinning assembly to obtain component A. Low-melting-point PA6 chips undergo a similar process, namely, melting in a screw extruder, filtration, metering with a metering pump, and then entering the spinning assembly to obtain component B. This step is to prepare for the subsequent preparation of core-sheath type bicomponent filaments.

[0025] Afterwards, component A and component B pass through the spinning assembly to obtain a sheath-core type bi-component filament, wherein PA6 is used as the sheath layer and PBT is used as the core layer, the mass ratio of PA6 is 10%-35%, the spinning speed is maintained at 4000-5500 m / min, the fineness of the bi-component filament is 1.2D-3.5D, and the elongation at break of the single filament is ≤85%; afterwards, a narrow-slit drafting machine and a negative pressure air blower are used to form a smooth and flat PA6 / PBT filament web C with a grammage of 20-35 gsm, and the PA6 / PBT filament web C enters the air-laying zone.

[0026] Meanwhile, the pulp fiber treated by the dry beating technology is added into the air-laying machine, the added amount of the pulp fiber is 30-50 gsm, the pulp fiber is deposited on the PA6 / PBT filament web C in the air-laying zone to form a composite web D, and afterwards, the composite web D is subjected to spray treatment, the spray treatment is spraying of pure water mist, and the spray amount is 20-50 L / min.

[0027] Afterwards, the dried PBT chips are melted, filtered and metered by a screw extruder, a metering pump and then enter the spinning assembly to obtain PBT filaments, the diameter of the PBT filaments is controlled at 1.5D-2.5D, and then the PBT filaments pass through a tubular drafting machine and a negative pressure air blower to form a smooth and flat PBT filament web, the grammage of the web is controlled at 15-25 gsm, and then the PBT filament web is laid on the surface of the composite web D to form a sandwich structure, and the overall thickness of the composite web D is controlled at below 2 mm.

[0028] Finally, the composite web D is subjected to reinforcement treatment by hot air drying and light rolling drying, and a high-temperature edible oil filament non-woven glue-free filter material is obtained, wherein the drying temperature in the hot air drying process is maintained at 160-200℃, the drying speed is maintained at 15-25 m / min, the overall water content of the material after drying is controlled at 3-5%, and the light rolling drying process adopts three-roller calendering to dry and calender the composite web, wherein the distance between the 1-2# calendering rollers is 0.3-1.1 mm, the 2-3# calendering rollers are subjected to pressure calendering treatment, the roller temperature is 120-160℃, the calendering pressure is 30-80 N / mm, and the overall thickness of the material is not less than 1 mm.

[0029] The high-temperature edible oil filament non-woven glue-free filter material prepared by the above-mentioned preparation method has a thickness of 0.6-1.5 mm and a grammage of 80-160 gsm.

[0030] The application has a sandwich structure of PA6 / PBT filament net-pulp fiber-PBT filament net, has excellent synergistic effect, effectively guarantees the strength of the filter material, and the PA6 / PBT bi-component fiber has adhesion, PA6 can penetrate into the internal structure of the pulp fiber and fill the gap between the fibers in the melting process, and when PA6 cools and solidifies, it is equivalent to forming a "physical adhesive" in the pulp fiber, which can combine the pulp fiber more tightly, this combination mode does not depend on hydrogen bond, but through the physical adhesion of PA6, avoids the problem of hydrogen bond failure and fiber shedding pollution when the glue-free filter paper is used to treat the recycled edible oil with high water content, and can maintain a stable physical structure when facing complex filtering conditions, avoids damage caused by external force or fluid impact, realizes zero shedding of pulp fiber, completely eliminates the problem of secondary pollution of filtered edible oil caused by fiber shedding, and effectively guarantees the purity and safety of the filtering product.

[0031] The overall processing technology of the application mainly relies on heat bonding technology, and the minimum heat bonding temperature is greater than 120 DEG C. The high-temperature heat bonding process is not only a key step to realize material reinforcement, but also ensures the close combination between the layers of the filter material and makes the structure more stable and durable, and has a significant high-temperature sterilization function. Under this temperature condition, bacteria and other microorganisms existing on the filter material can be effectively killed, so that the filter material of the application completely meets the requirements of food-grade materials, and overcomes the problem that the chemical adhesive of general filter materials is easily degraded and harmful components are separated out at high temperature.

[0032] Although the application is described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions described in the foregoing embodiments or make equivalent replacement to part of the technical features, and any modification, equivalent replacement, improvement, etc. within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A method for preparing a high-temperature edible oil filament nonwoven adhesive-free filter material, characterized in that, Includes the following steps: 1) Low-melting-point PA6 chips and dried PBT chips are melted by a screw extruder, filtered, metered by a metering pump, and then fed into the spinning assembly to obtain component A and component B; 2) Components A and B are used to obtain a core-sheath bicomponent filament through a spinning assembly, in which PA6 is used as the sheath and PBT is used as the core. The mass ratio of PA6 is 10%-35%. Then, a smooth PA6 / PBT filament web C with a basis weight of 20-35 gsm is formed by using a narrow slit drawing machine and a negative pressure fan. The PA6 / PBT filament web C enters the airflow web forming zone. 3) The pulp fibers processed by dry pulping technology are added to the air-flow web forming machine. The amount of pulp fibers added is 30-50 gsm. The pulp fibers are deposited on the PA6 / PBT filament web C in the air-flow web forming zone to form a composite web D. Then, pure water mist is sprayed onto the composite web D. 4) After drying, the PBT chips are melted by a screw extruder, filtered, metered by a metering pump, and then fed into the spinning assembly to obtain PBT filaments. After passing through a tubular drawing machine and a negative pressure fan, a smooth and flat PBT filament web is formed with a web weight of 15-25 gsm. Then, it is laid on the surface of the composite web D to form a PA6 / PBT filament web-pulp fiber-PBT filament web sandwich structure. 5) The composite fiber web D is reinforced by hot air drying and dehydration and light calendering drying to obtain a high-temperature edible oil filament nonwoven glue-free filter material. The light calendering drying process uses a three-roll calendering to dry and pre-treat the composite fiber web. The spacing between the 1-2# calendering rolls is 0.3-1.1mm, and the 2-3# calendering rolls are pressure calendered. The calendering roll temperature is 120-160℃, and the calendering pressure is 30-80N / mm.

2. The preparation method of a high-temperature edible oil filament nonwoven adhesive-free filter material according to claim 1, characterized in that, The fineness of the bicomponent filaments mentioned in step 2 is 1.2D-3.5D, the spinning speed is maintained at 4000-5500m / min, and the breaking elongation of the single filament is ≤85%.

3. The method for preparing a high-temperature edible oil filament nonwoven adhesive-free filter material according to claim 2, characterized in that, The spray treatment described in step 3 has a spray rate of 20-50 L / min.

4. The preparation method of a high-temperature edible oil filament nonwoven adhesive-free filter material according to claim 3, characterized in that, The PBT filament diameter mentioned in step 4 is 1.5D-2.5D, and the overall thickness of the composite fiber web D after laying is controlled below 2mm.

5. The preparation method of a high-temperature edible oil filament nonwoven adhesive-free filter material according to claim 4, characterized in that, During the hot air drying process described in step 5, the drying temperature is maintained at 160-200℃, the drying speed is maintained at 15-25m / min, and the overall moisture content of the material after drying is controlled at 3-5%.

6. A high-temperature edible oil filament nonwoven adhesive-free filter material, characterized in that, It is prepared by the preparation method described in any one of claims 1-5, and the material thickness is 0.6-1.5 mm and the basis weight is 80-160 gsm.

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