Method and special device for removing staining textile loose colour by multi-frequency ultrasound wave

[0035] The present invention will be further described below with reference to the specific drawings and embodiments.

[0036] The method for removing the floating color of dyed fabrics by multi-frequency ultrasonic wave comprises the following steps:

[0037] a. Install several ultrasonic vibration boxes in the washing container, the ultrasonic frequency that each ultrasonic vibration box can emit is 15-40KHz, and the ultrasonic frequency that each ultrasonic vibration box can emit is different;

[0038] b. Pour the washing liquid into the washing container, so that the washing liquid will submerge the ultrasonic vibration box;

[0039] c. Immerse the fabric to be washed in the washing solution and start each ultrasonic vibration box;

[0040] d. After washing, take out the fabric.

[0041] The ratio of the power of the ultrasonic waves emitted by any two ultrasonic vibration boxes is a fractional multiple (eg, 0.8 times) or a fractional multiple with an integer (eg, 1.2 times).

[0042] The special equipment for realizing the above-mentioned multi-frequency ultrasonic wave removal method of dyed fabric floating color, it includes a washing container 1, a plurality of ultrasonic vibration boxes 2 are arranged in the washing container 1, each ultrasonic vibration box 2 is provided with a wire tube 3, and the wire tube 3 is provided with a There is a connecting wire 4 connected with the ultrasonic vibration box 2 at one end, and the other end of the connecting wire 4 is connected with the ultrasonic generator, and the ultrasonic frequency that each ultrasonic vibration box 2 can emit is 15-40KHz, and each ultrasonic vibration box 2. 2 The ultrasonic frequencies that can be emitted are different, and the length of the ultrasonic vibration box 2 is adapted to the width of the washing container 1 .

[0043] Two upper and lower layers of cloth guide rollers 5 are arranged on the inner wall of the washing container 1 , and the ultrasonic vibration box 2 is arranged directly above the lower layer of cloth guide rollers 5 and parallel to the cloth guide rollers 5 . The ultrasonic vibration box 2 includes a vibration box 101, and several horizontal rows of ultrasonic transducers 102 are arranged on both sides of the vibration box 101). The top surface of the end is provided with a wire tube 3, and each wire tube 3 is provided with a connecting wire 4, and the two ends of the vibration box 101 are provided with installation parts 6, and the installation parts 6 are provided with installation holes 7. The ultrasonic transducers 102 in two adjacent horizontal rows are arranged in a staggered arrangement or in a longitudinal array. Moreover, the washing container 1 is arranged inside the bracket 8 , and a support leg 9 is provided at the outer edge and corner of the bottom end of the bracket 8 .

[0044] Advantages of Multi-frequency Ultrasonic Removal of Floating Color from Dyed Fabrics

[0045] Due to the diversity of fabrics, such as the color of the fabric, the thickness of the fabric, and the structure of the fabric, the fabric was washed with a single frequency of high-frequency (25khz-40khz) ultrasonic waves, and it was found that the washing effect was not very satisfactory. Thin dyed fabrics were washed The effect is good, and the washing effect of the thick dyed fabric surface is OK, but the washing effect of the floating color inside the fabric is not good. This is mainly the result of washing with a single ultrasonic frequency.

[0046] The washing device with multiple ultrasonic frequencies of the present invention can use two or three frequencies to alternately perform ultrasonic washing on textiles after pre-treatment during cleaning, or can simultaneously introduce dual or multiple frequencies into the same washing tank. The washing effect of single frequency, double frequency or multi frequency is much better than single frequency. For example, a dual-frequency ultrasonic with a frequency of 30khz and another frequency of 20khz is introduced into the washing tank. The ultrasonic wave with a low frequency has a longer wavelength and a larger force, which is easy to penetrate into the deep part of the fabric, while the high frequency Another ultrasonic wave has a good effect on the surface cleaning of the fabric, so using multi-frequency ultrasonic technology to pre-treat the fabric and wash it after dyeing has many advantages. Dual-frequency or multi-frequency operation also has the following advantages:

[0047] (1) It can eliminate the cleaning dead angle caused by the standing wave effect;

[0048] (2) It can reduce the corrosive effect of ultrasonic cavitation bubbles on the cleaned surface;

[0049] (3) It can be adapted to the washing of fabrics of different thicknesses;

[0050] (4) The critical value of ultrasonic power density in the cleaning solution can be increased.

[0051]The dyeing and finishing cleaning tank is generally a sound transmission medium with a limited boundary. When the sound wave (travelling wave) incident on the medium encounters the boundary, a reflected wave will be generated. Standing waves are formed by the superposition of traveling waves and reflected waves in the acoustic medium. After the standing wave is formed, the cleaning solution is divided into layers with an interval of about 1/4 wavelength (about 1 to 2 cm) in the propagation direction of the sound wave. Layers with high cleaning power and layers with very weak cleaning power are alternately distributed in these layers. In some areas, ultrasonic vibrations are almost completely canceled, creating dead spots for cleaning.

[0052] The principle of ultrasonic cleaning mainly relies on the cavitation bubbles in the cleaning solution. The formation process of cavitation bubbles is that, first of all, the suspended particles in the liquid or the special points in the liquid microstructure absorb the energy of the sound waves, so that the range of the special points becomes larger and the energy of the sound waves is more... A cavitation bubble with a very large energy-to-volume ratio is quickly formed there. Because the ratio of the energy carried by the cavitation bubble to its volume is extremely large, it can only exist for a short time before it explodes immediately. The explosion of cavitation bubbles forms many special points in the liquid microstructure around it, and these special points become the cores of new cavitation bubbles.... As can be seen, most of the cavitation bubbles in the cleaning liquid are Gathered together like a "tornado". The places where the "tornado" "scraped" formed excessive cleaning, and even had a corrosive effect on the surface to be cleaned; and the places that were "scraped" were not cleaned. Ultrasonic energy at a single frequency can also be excessively concentrated at the surface to be cleaned with special shapes and microscopic depressions, which can cause severe corrosion to these localized areas.

[0053] Frequent alternation of ultrasonic frequencies without a power multiple (or submultiple) relationship can produce different standing wave layers with complementary capabilities on the one hand, and on the other hand can greatly reduce harmful energy accumulation and corrosion on fabric surfaces. .

[0054] When the ultrasonic electric power applied to the transducer is small, the ultrasonic power density in the cleaning solution increases with the increase of the electric power. But when the electric power exceeds a certain critical point, the ultrasonic power density suddenly decreases. The reason is that when the electric power of the excitation transducer is small, the energy emitted from the surface of the sound source is relatively evenly distributed in the cleaning liquid, and the energy transfer process is in a balanced and stable state. When it increases to a certain value, the medium close to the surface of the sound source is excessively cavitated, and the acoustic resistance of this local medium increases with the increase of power, so part of the energy is intercepted in the thin medium layer on the surface of the sound source. , which aggravates the cavitation of the thin layer and increases the acoustic resistance of the thin layer... This is a positive feedback system. When the closed-loop gain of the system is greater than 1, the system loses stability, the acoustic resistance of the thin layer of medium on the surface of the sound source suddenly becomes large, and the ultrasonic power density in the cleaning solution suddenly decreases. After exceeding the critical point, part of the excess electrical power is converted into heat energy in the transducer, and another part is converted into heat energy in the thin dielectric layer on the surface of the sound source. Usually, even if the electric power of the excitation transducer is large, the degree of cavitation in the cleaning fluid cannot reach the maximum value before the critical point. The maximum value before this critical point is the so-called "ultrasonic power density critical value". Frequent alternation of ultrasonic frequency can reduce the effect of increasing the acoustic resistance of the thin layer of the medium on the surface of the sound source, thereby increasing the critical value of the ultrasonic power density in the cleaning solution, which is beneficial to remove the floating color of dyed fabrics.

[0055] Preliminary research has found that ultrasonic waves can strengthen the washing process after desizing, scouring, bleaching, dyeing, printing, finishing, etc., which can reduce processing time, reduce chemical consumption, steam consumption and water consumption, and improve product quality. When single-frequency ultrasound is used to act on the washing water in the sink, due to the influence of the standing wave field, the ultrasound field in the sink is not uniform, some places are strong, and some places are weak, resulting in poor washing effect at weak ultrasonic fields. At the same time, due to the different types of fabrics, the high-frequency ultrasonic waves are easily absorbed by the thick fabrics due to the short wavelength, and the ultrasonic attenuation is large, which makes the thick fabrics unclean. However, high-frequency ultrasonic has a better cleaning effect on the surface of the fabric due to its high vibration frequency.

[0056] As shown in Figures 1 and 2, the special equipment for realizing the multi-frequency ultrasonic wave removal method of dyed fabric floating color of the present invention is mainly used for various washing treatments of textiles. It includes a washing container 1, legs 9, a bracket 8, a cloth guide roller 5 and an ultrasonic vibration box 2. The washing container 1 is placed in the bracket 8 and can have multiple components. Multiple washing containers 1 can be arranged in front and back. 1. The fabrics to be washed are connected by rollers. There are seven cloth guide rollers 5 in each washing container 1. The cloth guide rollers 5 are divided into upper and lower rows. The fabric 10 goes around each cloth guide roller 5 from top to bottom and then from bottom to top. , an ultrasonic vibration box 2 is arranged above the downward cloth guide roller 5, and the washing liquid 11 completely immerses the ultrasonic vibration box 2 in it during washing.

[0057] The ultrasonic vibration box 2 is composed of a combination of an ultrasonic transducer 102 and an ultrasonic generator. It can radiate a variety of ultrasonic waves with the same power and different frequencies in the washing container 1, so that an ultrasonic field with uniform intensity is formed in the washing container 1. powerful. Ultrasonic waves of various frequencies act on the fabric 10, so that the mechanical effects of the ultrasonic waves (such as mechanical quantities such as particle vibration displacement, velocity, acceleration, sound pressure, etc. of the sound transmission medium) and thermal effects (part of the energy of the sound wave is absorbed by the medium during the propagation process). Under the action of these three effects, the liquid gas core in the washing container 1 expands and grows, and is filled with the surrounding liquid vapor or gas. Due to the disparity of internal and external pressure, the cavity collapses. Rupture, the concentrated sound field energy is released in a very short time and in a very small space, so that the medium locally forms a high temperature environment of hundreds to thousands of K and a high pressure environment of more than hundreds of atmospheres, and produces a strong impact force , to separate the residual dye floating color from the washed fabric, so as to achieve the purpose of removing the floating color of dyed fabric. In order to improve the treatment effect, the washing container 1 equipped with three ultrasonic vibration boxes 2 can be used in series to achieve the best treatment effect.

[0058] As shown in Figures 3 and 4, the multi-frequency ultrasonic transducer is composed of a vibrating box 101, an ultrasonic transducer 102 and a wire tube 3, etc. The wire tube 3 is provided with a connecting wire 4, and stainless steel is welded on the back of the radiating surface of the vibrating box 101. Screw, the front cover of the ultrasonic transducer 102 is coated with epoxy resin and then tightened with the screw. The ultrasonic transducer 102 is connected with a wire and then drawn out through a wire threading tube, and then connected to the multi-frequency ultrasonic generator.

[0059] In the present invention, the high-power ultrasonic vibration box 2 sends powerful multi-frequency ultrasonic waves to the water fabric through the ultrasonic transducer 102 . Under the premise of ensuring the washing effect of the fabric 10, some technical indicators for removing the floating color of the dyed fabric 10 are improved, and the processing temperature of the washing container 1 is lowered from the original 95 to 100 ° C to below 50 ° C, and the low temperature replaces the high temperature. Pre-treatment of dyed fabrics, resulting in significant savings in steam consumption and washing water consumption. It works as follows:

[0060] The treated fabric 10 enters the washing container 1 through the cloth guide roller 5. When the fabric 10 enters the ultrasonic vibration box 2, one side of the fabric is subjected to the frequency f. 1 , f 2 Ultrasound intensity w 1 When the fabric passes through the second cloth guide roller 5, it is subjected to the frequency f again 1 , f 2 Ultrasound intensity w 1 The ultrasonic direct radiation of , can also be of frequency f 3 , f 4 Ultrasound intensity w 1 The ultrasonic direct radiation of the 1 , f 2 Ultrasound intensity w 1 The ultrasonic direct radiation of , can also be of frequency f 5 , f 6 Ultrasound intensity w 1 Therefore, after entering the water tank, the fabric can obtain a variety of ultrasonic radiation, and the sound field of the entire water tank is synthesized by ultrasonic sound fields of multiple frequencies, so it is not easy to form standing waves, and the sound field is relatively uniform. The effect of cleaning the fabric is obvious, and the fabric is cleaned by ultrasonic waves of different frequencies of low frequency, medium frequency and high frequency, so that the cleaning effect of the thick material and the thin material is the same.

[0061] Installation and use of this special equipment:

[0062] 1. Equipment installation

[0063] After the dyeing process is completed, the current method of washing and removing floating color in industrial production is to use a series of continuous washing boxes that can be heated by steam. Multi-frequency ultrasonic does not change this basic structure, only a multi-frequency ultrasonic device is installed in the washing box to maintain the original production route, but only to change the temperature of the water in the washing box without heating the water to complete the washing process.

[0064] 2. Application in pre-treatment washing production

[0065] The production process uses standard singeing, cold heaping, flat washing, scouring, bleaching, and dyeing processes to treat cotton fabrics. The flat washing adopts conventional washing and ultrasonic washing, and then measures the wool efficiency, whiteness and other indicators of the washed fabrics. And compared with the conventional washing fabric to observe the use effect of ultrasonic washing device.

[0066] (1) Production process flow

[0067] Fabric pre-treatment process: singeing→cold heap→flat washing→scouring→bleaching.

[0068] In the flat washing process, we use steam heating water washing (conventional process) and ultrasonic normal temperature water washing (ultrasonic process), and other processes and process conditions are consistent.

[0069] (2) Test results of washing effect indicators

[0070] From the comparative analysis of the test results, it can be concluded that the wool effect and whiteness of the fabric after ultrasonic washing are slightly better than those of the conventional washing fabric, and the hand feel is also good. Ultrasonic water washing eliminates the need for heated steam and brings considerable economic benefits.

[0071] 3. Application in the production of washing to remove floating color after dyeing

[0072] (1) Production process flow

[0073] ①Regular washing

[0074] Padding liquid → drying → steaming (baking) → cold water washing for 1 grid → hot water washing for 4 grids at 85°C → soaping for 4 grids above 95 °C → cold water washing for 1 grid → drying

[0075] ②Ultrasonic washing

[0076] Padding liquid → drying → steaming (baking) → washing at room temperature for 5 grids → ultrasonic washing at room temperature for 3 grids → soaping for 1 grid above 95°C → washing in cold water for 1 grid → drying

[0077] (2) Test results

[0078] From the comparative analysis of the results, it can be concluded that the rubbing fastness and soaping fastness of the ultrasonically washed fabrics are better than those of the conventionally washed fabrics, and the product quality is stable. Ultrasonic washing saves steam and has better economic benefits.

[0079] Factory use economic benefits

[0080] The pre-treated and dyed fabrics are washed with ultrasonic waves at room temperature or by heating the temperature of 1-2 tanks to 40-50 ℃, and the washing effect reaches the effect of high-temperature washing at 95 ℃ in the original process. The ultrasonic wave itself also has a thermal effect. With the extension of the boot time, the water temperature of the water tank will gradually rise, so it is completely normal temperature washing after 1 to 2 hours. The original high-temperature washing line consumes 15 tons of steam per day (calculated as 20 hours) (each ton of steam is calculated at 140 yuan), a total of 2,100 yuan. The current ultrasonic washing line is calculated as 20 hours a day, and consumes 20 kilowatts of electricity per hour. Calculated at 0.6 yuan per kilowatt, the daily energy cost is: 0.6×20×20=240 yuan, the energy cost can be saved by 1860 yuan per day, and the annual energy cost can be saved by 1860×300=558,000 yuan. Each multi-frequency ultrasonic washing device is calculated at a price of 280,000 yuan, and the cost can be recovered in half a year.

[0081] In addition, production practice has proved that the ultrasonic washing technology after dyeing reduces water consumption. Each washing production line can save 30,000 tons of water per year, directly save 120,000 yuan in water costs, and reduce sewage discharge by 30,000 tons.

[0082]In the present invention, a high-power multi-frequency ultrasonic generator emits powerful multi-frequency ultrasonic waves to the water fabric in transmission through the multi-frequency transducer. Under the premise of ensuring that the floating color of the dyed fabric is removed and the dyeing fastness indexes reach the fastness index of the original washing process, the temperature of the washing water in the sink is lowered from 95 °C in the original washing process to 50 °C, and the low temperature washing process is replaced by high temperature washing. At the same time, it reduces the washing water, thereby greatly saving steam consumption and water consumption, and has certain social and economic benefits.

[0083] 1. Production application of pre-treatment washing

[0084] The production process is based on the standard singeing→cold heap→flat washing→scouring→bleaching→mercerizing process to treat cotton fabrics, in which the flat washing adopts ultrasonic washing, and other process parameters remain unchanged, and then the wool effect, Whiteness and other indicators, and compared with conventional washing fabrics, to obtain the effect of ultrasonic washing equipment.

[0085] 1. Production process:

[0086] Ultrasonic washing production process: singeing → cold heap → flat washing (ultrasonic) → scouring → bleaching

[0087] Among them, in the flat washing process, we use steam heating water washing (conventional process) and ultrasonic normal temperature water washing (ultrasonic process), and the process conditions of other processes are kept the same.

[0088] Table 1 Production process flow/parameter comparison

[0089] Flat washing process

[0090] 2. Production product index test:

[0091] Table 2 Comparison of the test results of various indicators after the pretreatment is completed

[0092]

[0093] It can be seen from the comparative analysis of the test results that the wool effect and whiteness of the cloth after ultrasonic washing are slightly better than those of the cloth washed with conventional water. And feel good too. Ultrasonic washing eliminates the need for heated steam, and because of the enhanced washing effect, the exchange rate of water is reduced, water resources are saved, and considerable economic benefits are brought.

[0094] Second, dyeing and washing production application

[0095] 1. Production process:

[0096] (1) Conventional washing:

[0097] Padding liquid → drying → steaming (baking) → cold water washing for 1 grid → hot water washing for 4 grids at 85°C → soaping for 4 grids above 95 °C → cold water washing for 1 grid → drying

[0098] (2) Ultrasonic washing

[0099] Padding liquid → drying → steaming (baking) → normal temperature washing 5 grids → normal temperature ultrasonic washing (soap washing) 3 grids → normal temperature washing 1 grid → cold water washing 1 grid → drying

[0100] 2. Production product index test

[0101] Table 3 Comparison of test results of various indicators after dyeing

[0102]

[0103] Table 4 Comparison of test results of various indicators after dyeing

[0104]

[0105] 100% cotton featherproof

[0106] It can be seen from the comparative analysis of the results that the rubbing fastness and soaping fastness indexes of the cloth after ultrasonic washing are close to those of conventional water washing, and some indicators are slightly better than those of conventional water washing. Moreover, fluctuations in product quality due to changes in steam temperature are reduced. Ultrasonic washing saves heated steam, reduces the exchange frequency of washing water, saves water resources, and brings greater economic benefits.

[0107] After the ultrasonic washing technology is used, it has achieved remarkable results in reducing steam costs, and at the same time, it is also effective in reducing water consumption, improving washing efficiency, and reducing waste water discharge. From August 2007 to January 2008, our company has produced 8.5 million meters of cotton products, saving 8,500 tons of steam, saving (emission reduction) water: 20,000 tons, and the annual cost saving is 1.05 million yuan .

[0108] In short, under the current country's strong requirement for enterprises to complete the task of energy saving and emission reduction, ultrasonic dyeing and washing technology is undoubtedly of great significance to printing and dyeing enterprises with large energy consumption.