Efficient and energy-saving continuous open-width bleaching and washing process for knitted fabric

Abstract

The invention discloses an efficient and energy-saving continuous open-width bleaching and washing process for knitted fabric. The process comprises the steps of fabric preparation, an efficient bleaching stage, bleaching treatment, a continuous open-width washing stage and drying treatment. The low-alkali bleaching finishing agent has the beneficial effects that low-alkali bleaching finishing of the fabric is realized, the output of heavy sewage is reduced, and the fabric has the advantages of good whiteness and strength, so that the problems that the energy utilization efficiency is low, and energy is wasted in each link from bleaching to washing to drying are solved.

Description

Technical Field

[0001] The invention relates to the technical field of fabric finishing, bleaching and washing, and in particular to a high-efficiency and energy-saving continuous open-width bleaching and washing process for knitted fabrics. Background Art

[0002] There are some problems that need to be solved in the current knitted fabric bleaching and washing process. Traditional processes are mostly intermittent, which leads to low equipment utilization and difficulty in improving production efficiency. In the bleaching process, the formula of chemical agents is not scientific and reasonable, and is often added based on experience, which not only causes waste of agents and increases costs, but may also damage fabric fibers due to excessive agents or poor reaction conditions. At the same time, the temperature control during the bleaching process is not precise enough, and heat loss is serious, further increasing energy consumption.

[0003] The washing process also has many shortcomings. Most of them use simple washing methods, such as single-stage washing or multi-stage downstream washing, which results in huge water consumption and poor removal of impurities such as residual bleach on the fabric. In addition, the traditional process does not recycle water resources enough, and a large amount of wastewater is directly discharged, which wastes resources and pollutes the environment. The energy utilization efficiency is low throughout the process, and there is energy waste in every link from bleaching to washing to drying, which makes the production cost high and does not meet the requirements of environmental protection and sustainable development. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the shortcomings of the prior art, the present invention provides a high-efficiency and energy-saving continuous open-width bleaching and washing process for knitted fabrics, which realizes low-alkali bleaching and finishing of fabrics and reduces the amount of heavy sewage generated. At the same time, the fabrics have the advantages of good whiteness and strength, thereby solving the problem of low energy utilization efficiency and energy waste in each link from bleaching to washing to drying.

[0006] (II) Technical solution

[0007] In order to achieve the above-mentioned low-alkali bleaching and finishing of fabrics, reduce the amount of heavy sewage generated, and at the same time, the fabrics have the advantages of good whiteness and strength, the specific technical scheme adopted by the present invention is as follows:

[0008] High-efficiency and energy-saving knitted fabric continuous open-width bleaching and washing process, including fabric preparation, high-efficiency bleaching stage, bleaching treatment, continuous open-width washing stage and drying treatment;

[0009] Fabric preparation includes inspection and smooth delivery.

[0010] Inspection stage: Check the surface of the knitted fabric section by section to see if there are any yarn breaks, holes, severe wrinkles, or impurities mixed in during the weaving process. Mark the defective parts. If the defective area is large or seriously affects the quality of the fabric, the problematic part will be cut off.

[0011] Flat conveying: The knitted fabrics that have passed the inspection are sent to the continuous flat-width processing equipment through the automatic conveying device. The conveying device is equipped with a tension adjustment system, which can automatically adjust the tension according to the material and thickness of the fabric to ensure that the fabric remains flat during the conveying process and avoid stretching deformation or wrinkles. A guide device is set at the feeding end to ensure that the fabric enters the bleaching process accurately.

[0012] The efficient bleaching stage includes bleaching liquid preparation and bleaching treatment.

[0013] Bleach solution configuration:

[0014] Adjustment of hydrogen peroxide concentration: The concentration of hydrogen peroxide is accurately determined according to the material of the fabric (such as pure cotton, polyester-cotton, spandex blended, etc.) and the initial color depth. For knitted fabrics with darker colors and pure cotton materials, the concentration of hydrogen peroxide is set to 4-5g / L; for fabrics with lighter colors or higher chemical fiber content in the blended ratio, the concentration can be reduced to 2-3g / L.

[0015] Stabilizer selection and dosage: Use environmentally friendly organic phosphonate stabilizers. The dosage is adjusted according to the hydrogen peroxide concentration and fabric material, generally 0.8-1.5g / L. During the preparation process, first fully dissolve the stabilizer in an appropriate amount of water to form a stable solution and then mix it with hydrogen peroxide.

[0016] Addition of activator: The activator is tetraacetylethylenediamine, the dosage is 0.4-0.8g / L, and it is evenly mixed into the mixed solution of hydrogen peroxide and stabilizer. An appropriate amount of chelating agent (such as disodium ethylenediaminetetraacetate, the dosage is 0.2-0.5g / L) can be added to remove metal ions in the water.

[0017] Bleaching treatment: spraying and rolling system, temperature and time control and environmental control and energy saving measures,

[0018] Spraying and rolling system: The prepared bleaching liquid is evenly sprayed on the surface of the knitted fabric through a high-precision spraying system. The spraying system consists of multiple nozzles. The angle and spacing of the nozzles can be automatically adjusted according to the fabric width and the equipment running speed to ensure the uniform distribution of the bleaching liquid in the fabric width direction. Subsequently, the fabric is rolled by a roller. The pressure of the roller is automatically adjusted according to the thickness and density of the fabric, and the pressure is between 2-5kg / cm 2 , so that the bleaching liquid can fully penetrate into the fabric.

[0019] Temperature and time control: The bleaching process is carried out in a sealed bleaching box, and the temperature is maintained at 80-95°C through a temperature control system. For thicker or tight fabrics, the bleaching time can be extended to 25-30 minutes; for thinner or loose fabrics, the bleaching time is controlled at 20-25 minutes. A circulating heating system is set in the bleaching box to make the bleaching liquid temperature uniform.

[0020] Environmental control and energy-saving measures: The bleaching box uses high-efficiency thermal insulation materials to reduce heat loss. At the same time, an adjustable vent is set on the top of the bleaching box. When the gas generated during the bleaching process reaches a certain concentration, the vent can be automatically opened to exhaust a small amount of gas, ensuring the safety of the bleaching environment and avoiding excessive loss of heat and chemicals.

[0021] The continuous open width washing stage includes

[0022] Multi-stage countercurrent rinsing system:

[0023] The first stage of water washing: The first stage of water washing uses hot water at a temperature of 50-60℃. Dilute sulfuric acid with a concentration of 0.5-1g / L is added to the hot water as a neutralizer. A stirring device is set in the water washing tank. The stirring speed is automatically adjusted according to the running speed and type of the fabric, generally at 30-60r / min, so that the fabric is fully in contact with the hot water. The fabric stays in the first stage of water washing for 5-8 minutes. The alkaline bleaching liquid components on the surface and inside of the fabric are preliminarily removed through the scouring and neutralization of hot water.

[0024] Subsequent washing tank settings: The water temperature of the subsequent washing tanks decreases in sequence. The water temperature of the second washing tank is 40-45℃, the third is 30-35℃, and the fourth is 20-25℃. Each washing tank is equipped with an efficient filtration system. The filtration system consists of multiple layers of filter screens and activated carbon adsorption layers. The pore size of the filter screen gradually decreases from the outside to the inside. The activated carbon adsorption layer can absorb trace chemical substances remaining in the water to ensure the quality of washing. The fabric stays in each washing tank for 3-5 minutes.

[0025] Countercurrent rinsing principle and control: Countercurrent rinsing is achieved through a pipeline and water pump system, that is, the relatively clean water in the rear washing tank flows back to the front washing tank. The flow rate of the water pump is automatically adjusted according to the water level of the washing tank and the processing volume of the fabric. During the entire washing process, the water quality parameters in each washing tank are monitored in real time through sensors, and the amount of neutralizer and other additives added is automatically adjusted according to the monitoring results.

[0026] Softening treatment and water recycling: The last stage of washing uses room temperature water and adds softener (concentration is 1-2g / L). Cationic softener can be used as softener. During the washing process, a water recycling system is set up to recycle the filtered and treated water in the rear washing tank to the water storage tank. After further water quality adjustment, it is reused in the front washing tank. The water recycling system is equipped with a disinfection device.

[0027] Drying

[0028] Selection and parameter setting of drying equipment: After washing, the knitted fabrics are dried by high-efficiency and energy-saving drying equipment. Hot air circulation drying equipment is selected, and the drying temperature is controlled at 100-120℃. It can be fine-tuned according to the material and thickness of the fabric. For pure cotton fabrics, the drying temperature can be appropriately increased to 110-120℃; for fabrics containing chemical fiber components, the temperature is controlled at 100-110℃.

[0029] Hot air circulation and humidity control: The hot air circulation system consists of a fan, a heating device and an air duct. The fan sends air into the heating device for heating and then blows it evenly toward the fabric through the air duct. A guide plate is provided in the air duct. A humidity sensor and a temperature sensor are provided in the drying equipment. The humidity sensor monitors the humidity in the drying room in real time. When the humidity reaches the set value, the fan speed and heating power are increased to speed up the drying speed. The temperature sensor prevents the drying temperature from being too high to damage the fabric. When the temperature exceeds the upper limit, the power of the heating device is automatically adjusted to ensure the drying effect and avoid damage to the fabric.

[0030] Energy-saving measures and exhaust gas treatment: The heating device of the drying equipment adopts efficient energy-saving heating technology. A heat recovery device and a purification device are installed at the exhaust gas outlet of the drying equipment. The heat recovery device can recycle the waste heat in the exhaust gas.

[0031] (III) Beneficial effects

[0032] Compared with the prior art, the present invention provides a highly efficient and energy-saving knitted fabric continuous open-width bleaching and washing process, which has the following beneficial effects:

[0033] Improved production efficiency: The continuous processing method avoids the equipment start-up and stop and waiting time of intermittent processing, so that the entire production process can be carried out uninterruptedly. The fabric achieves seamless connection between the bleaching, washing and drying links, greatly improving the output per unit time. Compared with the traditional intermittent process, the production efficiency can be increased by more than 50%.

[0034] Energy saving: In the bleaching process, precise temperature control and optimized bleaching liquid formula reduce energy waste caused by overheating and ineffective chemical reactions. The countercurrent rinsing and water resource recycling system in the washing process significantly reduce the energy required for water heating and water supply. The energy-saving heating technology and heat recovery device in the drying process further improve energy utilization. Comprehensive calculation shows that this process can save 30%-50% of energy compared with traditional processes.

[0035] Quality improvement

[0036] Uniform and stable bleaching effect: The special bleaching liquid formula and precise process parameters ensure the effective decomposition and utilization of hydrogen peroxide, making the bleaching effect of the fabric uniform and consistent. Both the surface and the inside of the fabric can achieve the ideal whiteness, and the whiteness is stable, and there will be no yellowing after long-term storage.

[0037] Thorough removal of impurities: The combination of multi-stage countercurrent rinsing and efficient filtration system can completely remove residual bleach, impurities and salts produced by neutralization reaction on the fabric. After washing, the fabric is highly clean and odorless, providing a good foundation for subsequent processing and use.

[0038] Improved hand feel: The softener added in the final stage of washing forms a uniform protective film on the surface of the fabric, making the fabric soft and smooth, improving the wearing comfort and added value of the fabric. The physical performance indicators (such as strength, elongation, etc.) of the knitted fabric treated by this process meet the standards, and the product qualification rate reaches more than 95%.

[0039] Environmental benefits

[0040] Chemical agent reduction: The optimized bleaching liquid formula reduces the use of chemical agents and reduces wastewater pollution caused by excessive use of agents. At the same time, the recycling of water resources in the washing process reduces the total amount of wastewater discharge and reduces the load on the environment.

[0041] Clean energy utilization and tail gas emission reduction: The energy-saving technology and tail gas treatment device used in the drying process reduce greenhouse gas emissions and air pollution generated during energy consumption. The entire process focuses on environmental protection from the source to the end, which meets the sustainable development requirements of the modern textile printing and dyeing industry. DETAILED DESCRIPTION

[0042] To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0043] According to an embodiment of the present invention, a highly efficient and energy-saving continuous open-width bleaching and washing process for knitted fabrics is provided.

[0044] The present invention is now further described in conjunction with the accompanying drawings and specific embodiments. According to an embodiment of the present invention, a high-efficiency and energy-saving continuous open-width bleaching and washing process for knitted fabrics, a high-efficiency and energy-saving continuous open-width bleaching and washing process for knitted fabrics includes fabric preparation, a high-efficiency bleaching stage, a bleaching treatment, a continuous open-width washing stage and a drying treatment;

[0045] Fabric preparation includes inspection and smooth delivery.

[0046] Inspection stage: Check the surface of the knitted fabric section by section to see if there are any yarn breaks, holes, severe wrinkles, or impurities mixed in during the weaving process. Mark the defective parts. If the defective area is large or seriously affects the quality of the fabric, the problematic part will be cut off.

[0047] Flat conveying: The knitted fabrics that have passed the inspection are sent to the continuous flat-width processing equipment through the automatic conveying device. The conveying device is equipped with a tension adjustment system, which can automatically adjust the tension according to the material and thickness of the fabric to ensure that the fabric remains flat during the conveying process and avoid stretching deformation or wrinkles. A guide device is set at the feeding end to ensure that the fabric enters the bleaching process accurately.

[0048] The efficient bleaching stage includes bleaching liquid preparation and bleaching treatment.

[0049] Bleach solution configuration:

[0050] Adjustment of hydrogen peroxide concentration: The concentration of hydrogen peroxide is accurately determined according to the material of the fabric (such as pure cotton, polyester-cotton, spandex blended, etc.) and the initial color depth. For knitted fabrics with darker colors and pure cotton materials, the concentration of hydrogen peroxide is set to 4-5g / L; for fabrics with lighter colors or higher chemical fiber content in the blended ratio, the concentration can be reduced to 2-3g / L.

[0051] Stabilizer selection and dosage: Use environmentally friendly organic phosphonate stabilizers. The dosage is adjusted according to the hydrogen peroxide concentration and fabric material, generally 0.8-1.5g / L. During the preparation process, first fully dissolve the stabilizer in an appropriate amount of water to form a stable solution and then mix it with hydrogen peroxide.

[0052] Addition of activator: The activator is tetraacetylethylenediamine, the dosage is 0.4-0.8g / L, and it is evenly mixed into the mixed solution of hydrogen peroxide and stabilizer. An appropriate amount of chelating agent (such as disodium ethylenediaminetetraacetate, the dosage is 0.2-0.5g / L) can be added to remove metal ions in the water.

[0053] Bleaching treatment: spraying and rolling system, temperature and time control and environmental control and energy saving measures,

[0054] Spraying and rolling system: The prepared bleaching liquid is evenly sprayed on the surface of the knitted fabric through a high-precision spraying system. The spraying system consists of multiple nozzles. The angle and spacing of the nozzles can be automatically adjusted according to the fabric width and the equipment running speed to ensure the uniform distribution of the bleaching liquid in the fabric width direction. Subsequently, the fabric is rolled by a roller. The pressure of the roller is automatically adjusted according to the thickness and density of the fabric, and the pressure is between 2-5kg / cm 2 , so that the bleaching liquid can fully penetrate into the fabric.

[0055] Temperature and time control: The bleaching process is carried out in a sealed bleaching box, and the temperature is maintained at 80-95°C through a temperature control system. For thicker or tight fabrics, the bleaching time can be extended to 25-30 minutes; for thinner or loose fabrics, the bleaching time is controlled at 20-25 minutes. A circulating heating system is set in the bleaching box to make the bleaching liquid temperature uniform.

[0056] Environmental control and energy-saving measures: The bleaching box uses high-efficiency thermal insulation materials to reduce heat loss. At the same time, an adjustable vent is set on the top of the bleaching box. When the gas generated during the bleaching process reaches a certain concentration, the vent can be automatically opened to exhaust a small amount of gas, ensuring the safety of the bleaching environment and avoiding excessive loss of heat and chemicals.

[0057] The continuous open width washing stage includes

[0058] Multi-stage countercurrent rinsing system:

[0059] The first stage of water washing: The first stage of water washing uses hot water at a temperature of 50-60℃. Dilute sulfuric acid with a concentration of 0.5-1g / L is added to the hot water as a neutralizer. A stirring device is set in the water washing tank. The stirring speed is automatically adjusted according to the running speed and type of the fabric, generally at 30-60r / min, so that the fabric is fully in contact with the hot water. The fabric stays in the first stage of water washing for 5-8 minutes. The alkaline bleaching liquid components on the surface and inside of the fabric are preliminarily removed through the scouring and neutralization of hot water.

[0060] Subsequent washing tank settings: The water temperature of the subsequent washing tanks decreases in sequence. The water temperature of the second washing tank is 40-45℃, the third is 30-35℃, and the fourth is 20-25℃. Each washing tank is equipped with an efficient filtration system. The filtration system consists of multiple layers of filter screens and activated carbon adsorption layers. The pore size of the filter screen gradually decreases from the outside to the inside. The activated carbon adsorption layer can absorb trace chemical substances remaining in the water to ensure the quality of washing. The fabric stays in each washing tank for 3-5 minutes.

[0061] Countercurrent rinsing principle and control: Countercurrent rinsing is achieved through a pipeline and water pump system, that is, the relatively clean water in the rear washing tank flows back to the front washing tank. The flow rate of the water pump is automatically adjusted according to the water level of the washing tank and the processing volume of the fabric. During the entire washing process, the water quality parameters in each washing tank are monitored in real time through sensors, and the amount of neutralizer and other additives added is automatically adjusted according to the monitoring results.

[0062] Softening treatment and water recycling: The last stage of washing uses room temperature water and adds softener (concentration is 1-2g / L). Cationic softener can be used as softener. During the washing process, a water recycling system is set up to recycle the filtered and treated water in the rear washing tank to the water storage tank. After further water quality adjustment, it is reused in the front washing tank. The water recycling system is equipped with a disinfection device.

[0063] Drying

[0064] Selection and parameter setting of drying equipment: After washing, the knitted fabrics are dried by high-efficiency and energy-saving drying equipment. Hot air circulation drying equipment is selected, and the drying temperature is controlled at 100-120℃. It can be fine-tuned according to the material and thickness of the fabric. For pure cotton fabrics, the drying temperature can be appropriately increased to 110-120℃; for fabrics containing chemical fiber components, the temperature is controlled at 100-110℃.

[0065] Hot air circulation and humidity control: The hot air circulation system consists of a fan, a heating device and an air duct. The fan sends air into the heating device for heating and then blows it evenly toward the fabric through the air duct. A guide plate is provided in the air duct. A humidity sensor and a temperature sensor are provided in the drying equipment. The humidity sensor monitors the humidity in the drying room in real time. When the humidity reaches the set value, the fan speed and heating power are increased to speed up the drying speed. The temperature sensor prevents the drying temperature from being too high to damage the fabric. When the temperature exceeds the upper limit, the power of the heating device is automatically adjusted to ensure the drying effect and avoid damage to the fabric.

[0066] Energy-saving measures and exhaust gas treatment: The heating device of the drying equipment adopts efficient energy-saving heating technology. A heat recovery device and a purification device are installed at the exhaust gas outlet of the drying equipment. The heat recovery device can recycle the waste heat in the exhaust gas.

[0067] Example 1

[0068] Fabric information, pure cotton knitted fabric, length 1000 meters, width 1.5 meters, fabric thickness is moderate, initial color is light yellow, with slight weaving impurities,

[0069] Process steps:

[0070] Fabric preparation: The fabric is carefully inspected on the inspection platform, and a small amount of parts with obvious impurities are marked and removed. The fabric is fed into the continuous flat-width processing equipment at a speed of 10m / min through an automatic conveyor. During the conveying process, the tension adjustment system keeps the fabric tension at 3kg / cm 2 ,

[0071] High-efficiency bleaching stage: prepare bleaching liquid with a hydrogen peroxide concentration of 3g / L, an organic phosphonate stabilizer of 1g / L, tetraacetylethylenediamine 0.5g / L, and disodium ethylenediaminetetraacetate 0.3g / L. Spray the bleaching liquid evenly on the fabric through a spraying system. The nozzle spacing is 20cm, the angle is 45°, and the roller pressure is set to 3kg / cm 2 The bleaching is carried out in a sealed bleaching box, the temperature is controlled at 85℃, the time is 25 minutes, the thermal conductivity of the insulation material of the bleaching box is 0.03W / (m·K), and the vents automatically exhaust a small amount of gas according to the gas concentration in the bleaching box.

[0072] Continuous open-width washing stage: the first stage of the washing tank has a hot water temperature of 55°C, a dilute sulfuric acid concentration of 0.8g / L, a stirring speed of 40r / min, and the fabric stays for 6 minutes. The subsequent washing tank temperatures are 42°C, 32°C, and 22°C, respectively, and each washing tank stays for 4 minutes. The filter mesh apertures in the filtration system are 0.5mm, 0.2mm, and 0.1mm from outside to inside, respectively. The thickness of the activated carbon adsorption layer is 10cm. The flow rate of the countercurrent rinsing water pump is automatically adjusted according to the water level of the washing tank to maintain a stable countercurrent speed. Finally, softener (cationic softener concentration 1.5g / L) is added to the room temperature water.

[0073] Drying treatment: hot air circulation drying equipment is used, the drying temperature is 110℃, the fan speed is automatically adjusted according to the humidity in the drying room, ranging from 1000-2000r / min, the heating device adopts heat pump technology, the heat recovery device has a recovery rate of 60%, and the purification device has a dust and odor removal rate of 90% in the exhaust gas. Example 2

[0074] Fabric information: Polyester-cotton blended (60% polyester, 40% cotton) knitted fabric, length 800 meters, width 1.2 meters, the fabric is thin, the initial color is light gray,

[0075] Process steps:

[0076] Fabric preparation: After checking the fabric, it is conveyed at a speed of 8m / min and the tension is maintained at 2kg / cm 2 ,

[0077] High-efficiency bleaching stage: 4g / L hydrogen peroxide, 1.2g / L stabilizer, 0.6g / L activator, 0.4g / L chelating agent in the bleaching solution, 15cm nozzle spacing, 60° angle, 2kg / cm roller pressure 2 , bleaching temperature 90℃, time 20 minutes, bleaching box is well insulated, vents are exhausted as needed,

[0078] Continuous open-width washing stage: the first stage of washing is 58℃, dilute sulfuric acid 0.6g / L, stirring 50r / min, the fabric stays for 5 minutes, the subsequent water temperature is 43℃, 33℃, 23℃, the stay time is 3, 4, 3 minutes respectively, the filtration system operates normally, the countercurrent rinsing is stable, the softener concentration of room temperature water is 1.8g / L,

[0079] Drying treatment: drying temperature 105℃, fan speed 800-1500r / min, heating and exhaust gas treatment devices operate effectively,

[0080] Example 3

[0081] Fabric information: Spandex blended (spandex 10%, cotton 90%) knitted fabric, length 1200 meters, width 1.8 meters, the fabric is thick and tight, the initial color is dark gray,

[0082] Process steps:

[0083] Fabric preparation: After strict inspection of the fabric, it is transported at a speed of 12m / min and a tension of 4kg / cm 2 ,

[0084] High-efficiency bleaching stage: hydrogen peroxide 5g / L, stabilizer 1.5g / L, activator 0.8g / L, chelating agent 0.5g / L, reasonable distribution of nozzles, roller pressure 5kg / cm 2 , bleaching temperature 92℃, time 30 minutes, bleaching box environment stable,

[0085] Continuous open-width washing stage: the first stage of washing is 60℃, dilute sulfuric acid 1g / L, stirring 60r / min, the fabric stays for 8 minutes, the subsequent water temperature is 45℃, 35℃, 25℃, the stay time is 5, 5, 5 minutes, the filtration and countercurrent rinsing are good, the softener concentration is 2g / L,

[0086] Drying treatment: drying temperature is 115℃, and fans and other equipment work in coordination.

[0087] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An efficient and energy-saving knitted fabric continuous open-width bleaching and washing process, comprising fabric preparation, an efficient bleaching stage, a bleaching treatment, a continuous open-width washing stage and a drying treatment; the characteristics are: Fabric preparation includes inspection and smooth delivery. Inspection stage: Check the surface of the knitted fabric section by section to see if there are any yarn breaks, holes, severe wrinkles, or impurities mixed in during the weaving process. Mark the defective parts. If the defective area is large or seriously affects the quality of the fabric, the problematic part will be cut off. Flat conveying: The knitted fabrics that have passed the inspection are sent to the continuous flat-width processing equipment through the automatic conveying device. The conveying device is equipped with a tension adjustment system, which can automatically adjust the tension according to the material and thickness of the fabric to ensure that the fabric remains flat during the conveying process and avoid stretching deformation or wrinkles. A guide device is set at the feeding end to ensure that the fabric enters the bleaching process accurately. The efficient bleaching stage includes bleaching liquid preparation and bleaching treatment. Bleach solution configuration: Adjustment of hydrogen peroxide concentration: The concentration of hydrogen peroxide is accurately determined according to the material of the fabric (such as pure cotton, polyester-cotton, spandex blended, etc.) and the initial color depth. For knitted fabrics with darker colors and pure cotton materials, the concentration of hydrogen peroxide is set to 4-5g / L; for fabrics with lighter colors or higher chemical fiber content in the blended ratio, the concentration can be reduced to 2-3g / L. Stabilizer selection and dosage: Use environmentally friendly organic phosphonate stabilizers. The dosage is adjusted according to the hydrogen peroxide concentration and fabric material, generally 0.8-1.5g / L. During the preparation process, first fully dissolve the stabilizer in an appropriate amount of water to form a stable solution and then mix it with hydrogen peroxide. Addition of activator: The activator is tetraacetylethylenediamine, the dosage is 0.4-0.8g / L, and it is evenly mixed into the mixed solution of hydrogen peroxide and stabilizer. An appropriate amount of chelating agent (such as disodium ethylenediaminetetraacetate, the dosage is 0.2-0.5g / L) can be added to remove metal ions in the water. Bleaching treatment: spraying and rolling system, temperature and time control and environmental control and energy saving measures, Spraying and rolling system: The prepared bleaching liquid is evenly sprayed on the surface of the knitted fabric through a high-precision spraying system. The spraying system consists of multiple nozzles. The angle and spacing of the nozzles can be automatically adjusted according to the fabric width and the equipment running speed to ensure the uniform distribution of the bleaching liquid in the fabric width direction. Subsequently, the fabric is rolled by a roller. The pressure of the roller is automatically adjusted according to the thickness and density of the fabric, and the pressure is between 2-5kg / cm 2 , so that the bleaching liquid can fully penetrate into the fabric. Temperature and time control: The bleaching process is carried out in a sealed bleaching box, and the temperature is maintained at 80-95°C through a temperature control system. For thicker or tight fabrics, the bleaching time can be extended to 25-30 minutes; for thinner or loose fabrics, the bleaching time is controlled at 20-25 minutes. A circulating heating system is set in the bleaching box to make the bleaching liquid temperature uniform. Environmental control and energy-saving measures: The bleaching box uses high-efficiency thermal insulation materials to reduce heat loss. At the same time, an adjustable vent is set on the top of the bleaching box. When the gas generated during the bleaching process reaches a certain concentration, the vent can be automatically opened to exhaust a small amount of gas, ensuring the safety of the bleaching environment and avoiding excessive loss of heat and chemicals. The continuous open width washing stage includes Multi-stage countercurrent rinsing system: The first stage of water washing: The first stage of water washing uses hot water at a temperature of 50-60℃. Dilute sulfuric acid with a concentration of 0.5-1g / L is added to the hot water as a neutralizer. A stirring device is set in the water washing tank. The stirring speed is automatically adjusted according to the running speed and type of the fabric, generally at 30-60r / min, so that the fabric is fully in contact with the hot water. The fabric stays in the first stage of water washing for 5-8 minutes. The alkaline bleaching liquid components on the surface and inside of the fabric are preliminarily removed through the scouring and neutralization of hot water. Subsequent washing tank settings: The water temperature of the subsequent washing tanks decreases in sequence. The water temperature of the second washing tank is 40-45℃, the third is 30-35℃, and the fourth is 20-25℃. Each washing tank is equipped with an efficient filtration system. The filtration system consists of multiple layers of filter screens and activated carbon adsorption layers. The pore size of the filter screen gradually decreases from the outside to the inside. The activated carbon adsorption layer can absorb trace chemical substances remaining in the water to ensure the quality of washing. The fabric stays in each washing tank for 3-5 minutes. Countercurrent rinsing principle and control: Countercurrent rinsing is achieved through a pipeline and water pump system, that is, the relatively clean water in the rear washing tank flows back to the front washing tank. The flow rate of the water pump is automatically adjusted according to the water level of the washing tank and the processing volume of the fabric. During the entire washing process, the water quality parameters in each washing tank are monitored in real time through sensors, and the amount of neutralizer and other additives added is automatically adjusted according to the monitoring results. Softening treatment and water recycling: The last stage of washing uses room temperature water and adds softener (concentration is 1-2g / L). Cationic softener can be used as softener. During the washing process, a water recycling system is set up to recycle the filtered and treated water in the rear washing tank to the water storage tank. After further water quality adjustment, it is reused in the front washing tank. The water recycling system is equipped with a disinfection device. Drying Selection and parameter setting of drying equipment: After washing, the knitted fabrics are dried by high-efficiency and energy-saving drying equipment. Hot air circulation drying equipment is selected, and the drying temperature is controlled at 100-120℃. It can be fine-tuned according to the material and thickness of the fabric. For pure cotton fabrics, the drying temperature can be appropriately increased to 110-120℃; for fabrics containing chemical fiber components, the temperature is controlled at 100-110℃. Hot air circulation and humidity control: The hot air circulation system consists of a fan, a heating device and an air duct. The fan sends air into the heating device for heating and then blows it evenly toward the fabric through the air duct. A guide plate is provided in the air duct. A humidity sensor and a temperature sensor are provided in the drying equipment. The humidity sensor monitors the humidity in the drying room in real time. When the humidity reaches the set value, the fan speed and heating power are increased to speed up the drying speed. The temperature sensor prevents the drying temperature from being too high to damage the fabric. When the temperature exceeds the upper limit, the power of the heating device is automatically adjusted to ensure the drying effect and avoid damage to the fabric. Energy-saving measures and exhaust gas treatment: The heating device of the drying equipment adopts efficient energy-saving heating technology. A heat recovery device and a purification device are installed at the exhaust gas outlet of the drying equipment. The heat recovery device can recycle the waste heat in the exhaust gas.

2. The high-efficiency and energy-saving knitted fabric continuous open-width bleaching and washing process according to claim 1, characterized in that: Fabric information, pure cotton knitted fabric, length 1000 meters, width 1.5 meters, fabric thickness is moderate, initial color is light yellow, with slight weaving impurities, Process steps: Fabric preparation: The fabric is carefully inspected on the inspection platform, and a small amount of parts with obvious impurities are marked and removed. The fabric is fed into the continuous flat-width processing equipment at a speed of 10m / min through an automatic conveyor. During the conveying process, the tension adjustment system keeps the fabric tension at 3kg / cm 2 , High-efficiency bleaching stage: prepare bleaching liquid with a hydrogen peroxide concentration of 3g / L, an organic phosphonate stabilizer of 1g / L, tetraacetylethylenediamine 0.5g / L, and disodium ethylenediaminetetraacetate 0.3g / L. Spray the bleaching liquid evenly on the fabric through a spraying system. The nozzle spacing is 20cm, the angle is 45°, and the roller pressure is set to 3kg / cm 2 The bleaching is carried out in a sealed bleaching box, the temperature is controlled at 85℃, the time is 25 minutes, the thermal conductivity of the insulation material of the bleaching box is 0.03W / (m·K), and the vents automatically exhaust a small amount of gas according to the gas concentration in the bleaching box. Continuous open-width washing stage: the first stage of the washing tank has a hot water temperature of 55°C, a dilute sulfuric acid concentration of 0.8g / L, a stirring speed of 40r / min, and the fabric stays for 6 minutes. The subsequent washing tank temperatures are 42°C, 32°C, and 22°C, respectively, and each washing tank stays for 4 minutes. The filter mesh apertures in the filtration system are 0.5mm, 0.2mm, and 0.1mm from outside to inside, respectively. The thickness of the activated carbon adsorption layer is 10cm. The flow rate of the countercurrent rinsing water pump is automatically adjusted according to the water level of the washing tank to maintain a stable countercurrent speed. Finally, softener (cationic softener concentration 1.5g / L) is added to the room temperature water. Drying treatment: hot air circulation drying equipment is used, the drying temperature is 110℃, the fan speed is automatically adjusted according to the humidity in the drying room, ranging from 1000-2000r / min, the heating device adopts heat pump technology, the heat recovery device has a recovery rate of 60%, and the purification device has a dust and odor removal rate of 90% in the exhaust gas.

3. The high-efficiency and energy-saving knitted fabric continuous open-width bleaching and washing process according to claim 1, characterized in that: Fabric information: Polyester-cotton blended (60% polyester, 40% cotton) knitted fabric, length 800 meters, width 1.2 meters, the fabric is thin, the initial color is light gray, Process steps: Fabric preparation: After checking the fabric, it is conveyed at a speed of 8m / min and the tension is maintained at 2kg / cm 2 , High-efficiency bleaching stage: 4g / L hydrogen peroxide, 1.2g / L stabilizer, 0.6g / L activator, 0.4g / L chelating agent in the bleaching solution, 15cm nozzle spacing, 60° angle, 2kg / cm roller pressure 2 , bleaching temperature 90℃, time 20 minutes, bleaching box is well insulated, vents are exhausted as needed, Continuous open-width washing stage: the first stage of washing is 58℃, dilute sulfuric acid 0.6g / L, stirring 50r / min, the fabric stays for 5 minutes, the subsequent water temperature is 43℃, 33℃, 23℃, the stay time is 3, 4, 3 minutes respectively, the filtration system operates normally, the countercurrent rinsing is stable, the softener concentration of room temperature water is 1.8g / L, Drying treatment: drying temperature is 105℃, fan speed is 800-1500r / min, heating and exhaust gas treatment devices operate effectively.

4. The high-efficiency and energy-saving knitted fabric continuous open-width bleaching and washing process according to claim 1, characterized in that: Fabric information: Spandex blended (spandex 10%, cotton 90%) knitted fabric, length 1200 meters, width 1.8 meters, the fabric is thick and tight, the initial color is dark gray, Process steps: Fabric preparation: After strict inspection of the fabric, it is transported at a speed of 12m / min and a tension of 4kg / cm 2 , High-efficiency bleaching stage: hydrogen peroxide 5g / L, stabilizer 1.5g / L, activator 0.8g / L, chelating agent 0.5g / L, reasonable distribution of nozzles, roller pressure 5kg / cm 2 , bleaching temperature 92℃, time 30 minutes, bleaching box environment stable, Continuous open-width washing stage: the first stage of washing is 60℃, dilute sulfuric acid 1g / L, stirring 60r / min, the fabric stays for 8 minutes, the subsequent water temperature is 45℃, 35℃, 25℃, the stay time is 5, 5, 5 minutes, the filtration and countercurrent rinsing are good, the softener concentration is 2g / L, Drying treatment: drying temperature is 115℃, and fans and other equipment work in coordination.