CN107937993A - A kind of preparation method of long bamboo fiber - Google Patents

Abstract

The invention discloses a preparation method of long bamboo raw fibers, belongs to the technical field of plant fiber production, and solves the problems of low production efficiency, low yield and heavy waste water pollution in the existing preparation method. The method comprises the following steps: bamboo slicing, high temperature and high pressure treatment, tearing treatment, enzyme treatment, chemical treatment, drying and carding treatment. The bamboo raw fiber obtained by the present invention has the following characteristics: the average length of the fiber is 4-5 cm, the fineness is not less than 100 centimetres, and the yield is not less than 60%. In addition, it also has the beneficial effects of high production efficiency (the annual output of a production line is not less than 50,000 tons), light waste water pollution, and soft fibers.

Description

A kind of preparation method of long bamboo fiber

technical field

The invention relates to a preparation method of bamboo raw fibers, in particular to a preparation method of long bamboo raw fibers, and belongs to the technical field of plant fiber production.

Background technique

Bamboo is an important forest resource. my country is the country with the most abundant bamboo resources, with more than 500 species of bamboo and a planting area of 5 million hectares. Over the past 20 years, the industrialization of bamboo has developed rapidly, and the bamboo industry has become a new economic growth point for my country's forestry development. Bamboo fiber is another new type of fiber after cotton, hemp, wool and silk. According to different processing methods, bamboo fiber can be divided into regenerated bamboo fiber (viscose fiber) and natural bamboo fiber (also known as bamboo fiber). The regenerated bamboo fiber is obtained by chemically treating the bamboo material to remove lignin, hemicellulose, pectin, resin and other non-cellulose components in the bamboo material as much as possible to obtain the bamboo dissolving pulp, and further using alkaline carbon disulfide to process the bamboo dissolving pulp. After processing such as dissolving and spinning, the viscose fiber finally obtained has changed the original properties of bamboo. Bamboo raw fibers are usually removed from bamboo green, bamboo yellow and bamboo nodes, and then use gears or rollers to repeatedly roll and press the bamboo, and then use multiple processes such as cooking, drying, fiber opening and carding to remove lignin and hemicellulose in bamboo. And pectin and other substances, the extracted raw fiber, the obtained fiber chemical content is very low, it is a real pure natural fiber. After carding, the bamboo fiber can be divided into long bamboo fiber and short bamboo fiber. The original bamboo fiber maintains the excellent properties of the original ecological bamboo fiber such as moisture absorption, breathability, wear resistance, and antibacterial. Compared with regenerated fiber (viscose fiber), bamboo fiber has the characteristics of high yield, and can be used in many fields such as textile fiber, wood-plastic composite material, pipeline, automobile lining, bedding, etc., among which long bamboo fiber is usually used for Preparation of textile fibers.

The actual production process of traditional bamboo fiber includes bamboo material preparation, one-stage high-temperature chemical treatment, rolling, two-stage high-temperature chemical treatment, drying, fiber opening treatment, and carding treatment. In this process flow, the multi-stage rolling process uses double rollers, and is usually operated manually, resulting in low production efficiency. The biological treatment is placed after the chemical treatment. Although it has been washed with water, the degree of water washing should not be too strong, so as not to cause the fiber yield to be too low, which will bring toxicity problems to the subsequent biological treatment, resulting in poor biological treatment effect. In the chemical treatment process, in addition to the addition of alkali, various chemical additives such as softeners must be added, and the amount of alkali used in the two-stage chemical treatment process is relatively large, and the wastewater pollution in the fiber preparation process is relatively large. At the same time, the multi-stage carding process will also cause fiber loss, especially short fiber loss, so the final yield is low. The fiber yield of traditional bamboo fiber preparation methods is generally not higher than 40%, and the annual output is not higher than 50,000. Ton.

Patent CN104651953A discloses a production method of bamboo raw fibers, which includes the following steps: remove the green bamboo on the surface of the bamboo, then put it into flowing water and immerse it for 10 to 20 days, take it out, clean it, and then split it along the direction of the fiber into a width of 10. Bamboo slices of mm to 20 mm; put the prepared bamboo slices into a high-pressure steam pot, then add a cooking solution 5 to 8 times the volume of the bamboo slices, heat to 200°C to 210°C, and cook for 4 hours ～5 hours, take out, rinse with water, drain; Wherein, described cooking solution is made of sodium hydroxide, sodium silicate, sodium thiosulfate, sodium sulfide and water by mass ratio sodium hydroxide: sodium silicate: sulfur Sodium sulfite: sodium sulfide: water=6:0.1:0.06:0.06:100, mixed uniformly to make; the bamboo chip after processing is put into the fermented liquid of 6 times～10 times of described bamboo chip volume, controls fermentation The temperature is 35-45°C, fermented for 4-6 hours, taken out, rinsed with water, and drained; wherein, the fermented liquid is composed of ligninase, pectinase, hemicellulase, water according to the mass ratio of ligninase : pectinase: hemicellulase: water=1:1:2:100, mixed uniformly and prepared; the treated bamboo chips were bleached and softened to obtain.

The above-mentioned bamboo fiber preparation method has problems such as low production efficiency, low yield, and serious waste water pollution, which limit the large-scale production and popularization of bamboo fiber.

Contents of the invention

The purpose of the present invention is to provide a method for preparing long bamboo raw fibers, which solves the problems of low production efficiency, low yield and heavy waste water pollution in the existing preparation method.

The technical scheme adopted in the present invention comprises the following steps:

Bamboo slices, high temperature and high pressure treatment, tearing treatment, enzyme treatment, chemical treatment, drying, carding treatment.

Specifically include the following steps:

Step 1, slicing: slice the bamboo;

Step 2, high-temperature and high-pressure treatment of bamboo slices: the bamboo slices obtained in step 1 are placed in a high-temperature (90-130° C.) high-pressure (1-3 MPa) container for steaming in a water bath for 20-90 minutes, and then drained for later use.

Step 3, bamboo chip tearing treatment: the bamboo chip processed in step 2 is subjected to 1-3 mechanical tearing treatments with a screw extrusion tearing machine to obtain bulky bamboo fiber bundles.

Step 4, enzyme treatment: the bulky bamboo fiber bundle obtained in step 3 is placed in a biological enzyme solution for treatment.

Step 5, chemical treatment: chemically treat the bamboo fiber bundles after the enzyme treatment in step 4, soften the bamboo fibers, and wash with water after the treatment.

Step 6, drying: the fibers obtained in Step 5 are dried using a convective flow dryer.

Step 7, carding: the fibers after drying in step 6 are combed by a carding machine to obtain short bamboo raw fibers.

go a step further:

The length 4-6 centimeter of the bamboo slice cut in the described step 1, thickness 2-3 millimeter. If the length of the bamboo slices is too long, the tearing machine is not easy to handle, and if the length is too short, it cannot meet the length requirements of long fibers. If the bamboo slices are too thick, the subsequent water bath treatment is not easy to soak, and the bamboo slices are too thin and easy to break.

The ratio of bamboo chips and water in the step 2 is that 1 kg of bamboo chips adds 3 liters of water.

The screw extrusion tearing machine that adopts in the described step 3 has a compression ratio of 4.

The biological enzyme used in step 4 is alkaline pectinase, the treatment temperature is 40-60°C, pH 7-9, the treatment time is 30-120 minutes, and the amount of alkaline pectinase is 5-20IU/kg dry The fiber has a mass concentration of 5-15% of the treated bamboo fiber bundles.

The chemical treatment in step 5 is carried out with alkaline sodium sulfite, the temperature is 80-130°C, the treatment time is 30-90 minutes, the amount of NaOH is 0.2-0.5% relative to the dry fiber mass, and the amount of Na ₂ SO ₃ is 0.3-0.5% % Relative to the absolute dry fiber mass, the mass concentration of the treated bamboo fiber bundles is 15-25%.

In the step 6, in the counterflow drying, the air temperature is 70-120° C., and the ratio of the fiber mass flow rate to the air mass flow rate is 0.02-0.06.

In the step 7, the fiber is carded 1-2 times by a carding machine. The number of carding is reduced, the cost is reduced, and the yield is increased. The more times of carding, the lower the yield of long fibers.

The present invention mainly replaces the traditional multi-roller rolling with the screw extrusion tearing machine, puts the biological treatment before the chemical treatment, replaces the traditional two-stage multiple chemical treatment with a single-stage alkaline sulfite treatment, removes the Fiber treatment, replacing traditional steam drying with impingement flow drying, and reducing the number of carding.

The invention adopts spiral tearing treatment to obtain looser bamboo fiber bundles, which is beneficial to the subsequent penetration of biological enzymes and chemicals, and can be continuously produced with high production efficiency. Putting biological treatment before chemical treatment avoids the toxicity problem caused by chemical treatment and improves the effect of biological treatment. The single-stage alkaline sulfite treatment replaces the traditional two-stage chemical treatment. Due to the sulfonation of lignin in the fiber, the bamboo fiber becomes hydrophilic and soft, which reduces the use of chemicals and reduces the amount of chemicals used while softening the fiber. Dosage. The impingement flow drying can completely separate the fiber bundles or fibers while realizing the fiber drying, replacing the traditional steam drying and fiber opening treatment.

The bamboo raw fiber obtained by the invention has the following characteristics: the average fiber length is 4-5 cm, the fineness is not less than 100 metric branches, and the yield is not less than 60%. In addition, it also has the beneficial effects of high production efficiency (the annual output of a production line is not less than 50,000 tons), light waste water pollution, and soft fibers.

Detailed ways

Example 1

The preparation method of flexible bamboo fiber, comprises the steps:

Step 1, slicing: slice the bamboo, the length of the bamboo slice is 4-6 cm, and the thickness is 2-3 mm.

Step 2, high-temperature and high-pressure treatment of bamboo chips: place the bamboo chips in a container at 110° C. and a pressure of 1.5 MPa for hot water pretreatment for 30 minutes. The ratio of wood chips to water is 1 kg of wood chips corresponds to 3 liters of water.

Step 3, bamboo chip tearing treatment: the bamboo chip after high temperature and high pressure treatment is subjected to two mechanical tearing treatments with a screw extrusion tearing machine with a compression ratio of 4, to obtain bulky bamboo fiber bundles.

Step 4, enzyme treatment: place the bulky bamboo fiber bundles at a temperature of 50°C and a pH 8.0 alkaline pectinase mixture for 90 minutes, the amount of alkaline pectinase is 15IU/kg dry fiber, The mass concentration of the treated bamboo fiber bundles is 10%.

Step 5, chemical treatment: the bamboo fiber bundle after the enzyme treatment is chemically treated with alkaline sodium sulfite, the temperature is 100 ° C, the treatment time is 60 minutes, the amount of _NaOH is 0.3% relative to the dry fiber mass, and the amount _of Na2SO3 is 0.4% % is relative to the absolute dry fiber mass, and the mass concentration of the treated bamboo fiber bundles is 15%. After the treatment, wash with water to soften the original bamboo fiber.

Step 6. Drying: The fibers obtained by the chemical treatment are dried by a counterflow dryer, the air temperature is 110° C., and the ratio of the fiber mass flow rate to the air mass flow rate is 0.05.

Step 7, carding: the dried fibers are carded twice on a carding machine to obtain raw bamboo fibers with a fiber yield of 65%, an average fiber length of 4.42 cm, and a fiber fineness of 105 centimetres.

Example 2

The preparation method of bamboo raw fiber, comprises the steps:

Step 1, slicing: slice the bamboo, the length of the bamboo slice is 4-6 cm, and the thickness is 2-3 mm.

Step 2, high-temperature and high-pressure treatment of bamboo chips: place the bamboo chips in a container at 120° C. and a pressure of 1.2 MPa for hot water pretreatment for 40 minutes. The ratio of wood chips to water is 1 kg of wood chips corresponds to 3 liters of water.

Step 3, bamboo chip tearing treatment: the bamboo chip after high temperature and high pressure treatment is subjected to two mechanical tearing treatments with a screw extrusion tearing machine with a compression ratio of 4, to obtain bulky bamboo fiber bundles.

Step 4. Enzyme treatment: place the bulky bamboo fiber bundles in an alkaline pectinase mixture with a temperature of 55° C. and a pH of 8.5 for 80 minutes. The amount of alkaline pectinase is 18 IU/kg dry fiber. The mass concentration of the treated bamboo fiber bundles is 12%.

Step 5, chemical treatment: carry out chemical treatment with alkaline sodium sulfite through the bamboo fiber bundle after enzyme treatment, temperature 120 ℃, treatment time 40 minutes, NaOH consumption is 0.2% relative to absolute dry fiber quality, Na ₂ SO _The consumption is 0.3% relative to the absolute dry fiber mass, the mass concentration of the treated bamboo fiber bundles is 15%. After the treatment, wash with water to soften the original bamboo fiber.

Step 6. Drying: The fibers obtained by the chemical treatment are dried by a counterflow dryer, the air temperature is 100° C., and the ratio of the fiber mass flow rate to the air mass flow rate is 0.04.

Step 7, carding: the dried fibers are carded once on a carding machine to obtain raw bamboo fibers with a fiber yield of 73%, an average fiber length of 4.85 cm, and a fiber fineness of 112 metric branches.

Example 3

The preparation method of bamboo raw fiber, comprises the steps:

Step 1, slicing: slice the bamboo, the length of the bamboo slice is 4-6 cm, and the thickness is 2-3 mm.

Step 2, high-temperature and high-pressure treatment of bamboo slices: place the bamboo slices in a container at 125° C. and a pressure of 1.0 MPa for hot water pretreatment for 20 minutes. The ratio of wood chips to water is 1 kg of wood chips corresponds to 3 liters of water.

Step 3, bamboo chip tearing treatment: the bamboo chip after high temperature and high pressure treatment is subjected to three mechanical tearing treatments with a screw extrusion tearing machine with a compression ratio of 4, to obtain bulky bamboo fiber bundles.

Step 4, enzyme treatment: place the bulky bamboo fiber bundles in an alkaline pectinase mixture with a temperature of 60°C and a pH of 8.0 for 70 minutes, and the amount of alkaline pectinase is 10IU/kg dry fiber, The mass concentration of the treated bamboo fiber bundles is 10%.

Step 5, chemical treatment: carry out chemical treatment with alkaline sodium sulfite through the bamboo fiber bundle after enzyme treatment, temperature 130 ℃, treatment time 30 minutes, NaOH consumption is 0.4% relative to absolute dry fiber quality, Na ₂ SO _The consumption is 0.3% relative to the absolute dry fiber mass, the mass concentration of the treated bamboo fiber bundle is 20%. After the treatment, wash with water to soften the original bamboo fiber.

Step 6. Drying: The fibers obtained by the chemical treatment are dried with a counterflow dryer, the air temperature is 80° C., and the ratio of the fiber mass flow rate to the air mass flow rate is 0.02.

Step 7, carding: the dried fibers are carded twice on a carding machine to obtain raw bamboo fibers with a fiber yield of 62%, an average fiber length of 4.27 centimeters, and a bamboo fiber with a fiber fineness of 130 centimetres.

The bamboo raw fiber prepared by the invention has high yield, light waste water pollution in the preparation process, and high production efficiency.

Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments we have described are only illustrative, rather than used to limit the scope of the present invention. Equivalent modifications and changes made by skilled personnel in accordance with the spirit of the present invention shall fall within the protection scope of the claims of the present invention.

Claims (9)

1. A kind of 1. preparation method of long bamboo fiber, it is characterised in that：Comprise the following steps：Bamboo wood section, high temperature high pressure process, Tear processing, enzymatic treatment, chemical treatment, drying, combing processing.
2. 2. the preparation method of long bamboo fiber according to claim 1, it is characterised in that：Specifically include following steps：

   Step 1, section：Bamboo is cut into slices；

   Step 2, bamboo chip high temperature high pressure process：The bamboo chip that step 1 is obtained is placed in 90-130 DEG C of high temperature, the container of high pressure 1-3MPa Middle progress water-bath boiling 20-90 minutes, it is then drained and standby；

   Step 3, bamboo chip tear processing：Bamboo chip after step 2 is handled is carried out at 1-3 roads mechanical tear with screw extrusion shredder Reason, obtains the bamboo fiber bundle of bulk shape；

   Step 4, enzymatic treatment：The bulk shape bamboo fiber bundle that step 3 is obtained, which is placed in biological enzyme liquid, to be handled；

   Step 5, chemical treatment：Bamboo fiber bundle after step 4 enzymatic treatment is chemically treated, softens bamboo fibre, processing Finish and washed；

   Step 6, drying：The fiber utilization impinging stream drying machine that step 5 obtains is dried；

   Step 7, comb：By the dried fiber of step 6 up to long bamboo fiber after carding machine combs.
3. 3. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：The bamboo being cut into the step 1 4-6 centimetres of leaf length, 2-3 millimeters of thickness.
4. 4. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：Bamboo chip and water in the step 2 Ratio for 1kg bamboo chips add 3 liters of water.
5. 5. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：Used in the step 3 Screw extrusion shredder, its compression ratio are 4.
6. 6. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：Used in the step 4 Biology enzyme is alkaline pectase, and treatment temperature is 40-60 DEG C, pH 7-9, processing time 30-120 minute, alkaline pectin enzyme dosage For 5-20IU/kg bone dry fibers, the bamboo fiber bundle mass concentration of processing is 5-15%.
7. 7. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：In the step 5 at chemistry Reason is carried out using alkaline sodium sulfite, and temperature is 80-130 DEG C, and processing time 30-90 minute, NaOH dosages are 0.2-0.5% phases For bone dry fiber quality, Na₂SO₃Dosage is dense relative to bone dry fiber quality, the bamboo fiber bundle quality of processing for 0.3-0.5% Spend for 15-25%.
8. 8. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：Head-on collision drains off in the step 6 The drying condition of dry machine is：70-120 DEG C of gas flow temperature, the ratio between fibre mass flow and gas mass flows are 0.02-0.06.
9. 9. the preparation method of long bamboo fiber according to claim 2, it is characterised in that：Fiber passes through in the step 7 Carding machine combs 1-2 times.