High-temperature edible oil filament non-woven non-adhesive filtering material and preparation method thereof

Abstract

The invention discloses a high-temperature edible oil filament non-woven non-adhesive filtering material and a preparation method thereof, the non-woven filtering material with a sandwich structure of a PA6 / PBT (Polyamide 6 / Polybutylene Terephthalate) bi-component filament fiber web, pulp fiber and PBT filament fiber web is prepared based on a spunbond and air laying technology, the thickness of the filtering material is 0.6-1.5 mm, and the gram weight is 80-160gsm; the strength of the filtering material is structurally guaranteed, the problems that hydrogen bonds fail and fibers fall off to cause pollution when the non-adhesive filter paper treats the recycled edible oil with large water content are solved, and the problem that secondary pollution is caused to the filtered edible oil due to fiber falling is thoroughly eradicated; the processing technology depends on the heat bonding technology, the problems that a chemical bonding agent of a common filter material is prone to degradation and harmful components are separated out at high temperature are solved, material reinforcement is achieved in the high-temperature heat bonding process, the remarkable high-temperature sterilization function is achieved, and the filter material meets the requirements of food-grade materials.

Description

Technical Field

[0001] The present invention relates to the field of edible oil filtration, and specifically to a high-temperature edible oil filament non-woven glue-free filtration material and a preparation method thereof. Background Art

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

[0003] Existing edible oil filtration materials mainly include metal filter meshes, filter papers, etc. They have problems such as low filtration accuracy, and the chemical adhesives in the filtration materials are prone to degradation and harmful component precipitation under high-temperature conditions, resulting in pollution of edible oil and posing a potential threat to human health; while glue-free filtration materials maintain the strength of the material through hydrogen bonding. When encountering recycled edible oil with a relatively high moisture content, the hydrogen bonding is prone to failure, resulting in fiber shedding of the filtration material and causing secondary pollution to the filtered edible oil. Summary of the Invention

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

[0005] To achieve the above purpose, the present invention provides the following technical solutions: A preparation method of a high-temperature edible oil filament non-woven glue-free filtration material, comprising the following steps: 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 for spinning to obtain component A and component B; 2), Component A and component B pass through the spinning assembly to obtain a core-sheath type bicomponent filament, where 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 draw frame and a negative pressure suction fan are used to form a flat and smooth PA6 / PBT filament web C with a grammage of 20-35 gsm, and the PA6 / PBT filament web C enters the air-laying area; 3), The pulp fibers treated by the dry beating technology are added to an air-laying machine, and the addition amount of the pulp fibers is 30-50 gsm. The pulp fibers are deposited on the PA6 / PBT filament web C through the air-laying area to form a composite web D, and then the composite web D is subjected to a spraying treatment, and the spraying treatment is to spray pure water mist; 4), The dried PBT chips are melted, filtered, and metered by a metering pump through a screw extruder and then enter the spinning assembly to obtain PBT filaments. After passing through a tube drawing machine and a negative pressure suction fan, a smooth and flat PBT filament web is formed. The grammage of the web is 15-25 gsm, and then it is laid on the surface of the composite web D to form a sandwich structure; 5), The composite web D is strengthened by hot air drying and calendaring drying to obtain a non-woven adhesive-free filter material for high-temperature cooking oil filaments.

[0006] As a further scheme of the present invention: the fineness of the bicomponent filaments described in step 2 is 1.2D-3.5D, the spinning speed is maintained at 4000-5500 m / min, and the single filament breaking elongation rate ≤ 85%.

[0007] As a further scheme of the present invention: the pure water mist spraying amount described in step 3 is 20-50 L / min.

[0008] As a further scheme of the present invention: the diameter of the PBT filaments described in step 4 is 1.5D-2.5D, and the overall thickness of the laid composite web D is controlled below 2 mm.

[0009] As a further scheme of the present invention: during the hot air drying process in step 5, the drying temperature is maintained at 160-200 °C, the drying speed is maintained at 15-25 m / min, and the overall moisture content of the dried material is controlled at 3-5%.

[0010] As a further scheme of the present invention: in the calendaring drying process in step 5, a three-roll calender is used for drying and calendering pretreatment of the composite web. The nip between the 1-2# calender rolls is 0.3-1.1 mm, the 2-3# calender rolls are treated with pressure calendering, the calender roll temperature is 120-160 °C, the calendering pressure is 30-80 N / mm, and the overall thickness of the material is not less than 1 mm.

[0011] The present invention also provides a non-woven adhesive-free filter material for high-temperature cooking oil filaments, which is prepared by the above preparation method. The thickness of the material is 0.6-1.5 mm, and the grammage is 80-160 gsm.

[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention innovatively adopts a sandwich structure of PA6 / PBT filament web - pulp fiber - PBT filament web in terms of structure, effectively ensuring the strength of the filter material, avoiding the problems of hydrogen bond failure and fiber shedding pollution of the non - adhesive filter paper when treating recycled edible oil with high moisture content. At the same time, it can avoid damage caused by external force and fluid impact, achieving zero shedding of pulp fibers and completely eliminating the problem of secondary pollution of the filtered edible oil caused by fiber shedding, effectively ensuring the purity and safety of the filter product. 2. The overall processing technology of the present invention relies on thermal bonding technology, overcoming the problem that chemical binders in general filter materials are prone to degradation and release of harmful components at high temperatures. The minimum thermal bonding temperature of the present invention is > 120 °C. This high - temperature thermal bonding process not only realizes material reinforcement but also has a significant high - temperature disinfection function, which can effectively kill bacteria and other microorganisms existing on the filter material, making the filter material of the present invention meet the requirements of food - grade materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a flow chart of a preparation method of a high - temperature edible oil filament non - woven non - adhesive filter material. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. 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 efforts shall fall within the protection scope of the present invention.

[0015] This application provides a high - temperature edible oil filament non - woven non - adhesive filter material and its preparation method. The flow chart of the preparation method is as Figure 1 shown. Next, the high - temperature edible oil filter non - woven material and its preparation method will be described in conjunction with the embodiments.

[0016] A preparation method of a high - temperature edible oil filament non - woven non - adhesive filter material. First, the PBT chips are dried to remove the moisture therein, then melted by a screw extruder, followed by filtration to remove impurities, and then accurately metered by a metering pump and fed into the spinning assembly to obtain component A; the low - melting - point PA6 chips also undergo a similar process, that is, melted by a screw extruder, filtered, metered by a metering pump and then fed into the spinning assembly to obtain component B. This step is to prepare for the subsequent preparation of core - sheath type bicomponent filaments.

[0017] Afterwards, Component A and Component B are passed through a spinning pack to obtain a core-sheath type bicomponent filament, where PA6 serves as the sheath and PBT serves as the core. The mass ratio of PA6 is 10% - 35%. The spinning speed is maintained at 4000 - 5500 m / min. The fineness of the bicomponent filament is 1.2D - 3.5D, and the single filament breaking elongation rate ≤ 85%. Afterwards, a narrow slit drawframe and a negative pressure suction fan 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 area.

[0018] Meanwhile, the pulp fibers treated by the dry beating technology are added into the air-laying machine. The addition amount of the pulp fibers is 30 - 50 gsm. The pulp fibers are deposited on the PA6 / PBT filament web C through the air-laying area to form a composite web D. Afterwards, the composite web D is subjected to spray treatment, and the spray treatment is to spray pure water mist, and the spray amount is 20 - 50 L / min.

[0019] Afterwards, the dried PBT chips are melted, filtered, and metered by a metering pump through a screw extruder and then enter the spinning pack to obtain PBT filaments. The diameter of the PBT filaments is controlled at 1.5D - 2.5D. Then, through a tube drawframe and a negative pressure suction fan, a smooth and flat PBT filament web is formed. The grammage of the web is controlled at 15 - 25 gsm. Afterwards, it 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 below 2 mm.

[0020] Finally, the composite web D is strengthened by hot air drying dehydration and calendering drying to obtain a high-temperature edible oil filament non-woven adhesive-free filter material. During the hot air drying process, the drying temperature is maintained at 160 - 200 °C, the drying speed is maintained at 15 - 25 m / min, and the overall moisture content of the dried material is controlled at 3 - 5%. During the calendering drying process, a three-roll calender is used to perform drying and calendering pretreatment on the composite web. The nip between the 1st - 2nd calender rolls is 0.3 - 1.1 mm, the 2nd - 3rd calender rolls are subjected to pressure calendering treatment, the calender roll temperature is 120 - 160 °C, the calendering pressure is 30 - 80 N / mm, and the overall thickness of the material is not less than 1 mm.

[0021] The high-temperature edible oil filament non-woven adhesive-free filter material prepared by the above method for preparing a high-temperature edible oil filament non-woven adhesive-free filter material has a material thickness of 0.6 - 1.5 mm and a grammage of 80 - 160 gsm.

[0022] In terms of structure, the present invention innovatively adopts a sandwich structure of PA6 / PBT filament web - pulp fiber - PBT filament web, which has excellent synergistic effects. It not only effectively ensures the strength of the filter material, but also the PA6 / PBT bicomponent fibers take into account the bonding effect. During the melting process, PA6 can penetrate into the internal structure of the pulp fibers and fill the gaps between the fibers. When PA6 cools and solidifies, it is equivalent to forming a kind of "physical binder" inside the pulp fibers, binding the pulp fibers more closely together. This bonding method does not rely on hydrogen bonds, but through the physical bonding effect of PA6, avoiding the problems of hydrogen bond failure and fiber shedding pollution when the gum-free filter paper is used to treat recycled cooking oil with high moisture content. At the same time, when facing complex filtration conditions, it can maintain a stable physical structure, avoid being damaged by external forces or fluid impacts, achieve zero shedding of pulp fibers, and completely eliminate the problem of secondary pollution of the filtered cooking oil caused by fiber shedding, effectively ensuring the purity and safety of the filtration product.

[0023] The overall processing technology of the present invention mainly relies on thermal bonding technology, and its minimum thermal bonding temperature > 120°C. This high-temperature thermal bonding process is not only a key step to realize material reinforcement, ensuring the tight combination between layers of the filter material and making its structure more stable and durable, but also has a significant high-temperature disinfection function. Under this temperature condition, it can effectively kill bacteria and other microorganisms existing on the filter material, making the filter material of the present invention fully meet the requirements of food-grade materials, and at the same time overcoming the problem that chemical binders in general filter materials are prone to degradation and release harmful components at high temperatures.

[0024] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a high-temperature edible oil filament nonwoven glue-free filter material, characterized in that: The following steps are involved: 1) The low melting point PA6 slices and the dried PBT slices are melted, filtered and metered by a screw extruder and then enter the spinning assembly to obtain component A and component B; 2) Component A and component B are passed through a spinning assembly to obtain a sheath-core bicomponent filament, 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 drawing machine and a negative pressure suction fan are used to form a flat and smooth PA6 / PBT filament web C with a gram weight of 20-35gsm. The PA6 / PBT filament web C enters the airflow forming area; 3) Pulp fibers treated by dry beating technology are added to the air-laid machine, and the amount of pulp fibers added is 30-50gsm. The pulp fibers are deposited on the PA6 / PBT filament web C through the air-laid area to form a composite web D. The composite web D is then sprayed with pure water mist. 4) The dried PBT slices are melted, filtered and metered by a screw extruder, and then enter the spinning assembly to obtain PBT filaments. After passing through a tubular drawing machine and a negative pressure suction fan, a smooth and flat PBT filament web is formed. The web weight is 15-25gsm, and then it is stacked on the surface of the composite web D to form a 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 non-glue filter material.

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

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

4. The method for preparing a high-temperature edible oil filament nonwoven glue-free filter material according to claim 3, characterized in that: The diameter of the PBT filaments described in step 4 is 1.5D-2.5D, and the overall thickness of the composite fiber web D after stacking is controlled to be less than 2 mm.

5. The method for preparing a high-temperature edible oil filament nonwoven glue-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° C., the drying speed is maintained at 15-25 m / min, and the overall moisture content of the material after drying is controlled at 3-5%.

6. The method for preparing a high-temperature edible oil filament nonwoven glue-free filter material according to claim 5, characterized in that: The light calendering drying process described in step 5 uses three-roll calendering to dry and calender the composite fiber web for pre-treatment, wherein the spacing of the 1-2# calendering rollers is 0.3-1.1mm, the 2-3# calendering rollers use pressure calendering treatment, the pressure roller temperature is 120-160℃, the calendering pressure is 30-80N / mm, and the overall material thickness is not less than 1mm.

7. A high-temperature edible oil filament nonwoven non-adhesive filter material, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 6, and the material thickness is 0.6-1.5 mm and the gram weight is 80-160 gsm.

Images