Method for removing residual silicone oil in spandex

Abstract

The invention discloses a method for removing residual silicone oil in spandex, which is characterized by comprising the following steps: S1, putting the spandex into a closed ultrasonic cleaning machine, pouring a solvent and enabling the liquid level of the solvent to completely immerse the spandex; s2, an ultrasonic cleaning machine is started for cleaning, and after cleaning, the spandex containing the solvent is subjected to filter pressing to remove the solvent; s3, putting the spandex into a vacuum tank, heating and vacuumizing; s4, after vacuumizing is stopped, vacuum is slowly relieved, the vacuum tank is opened, and the spandex is taken out. The method has the advantages that 1, the silicone oil removal rate is high, and the amount of residual silicone oil is small; 2, silicone oil is removed by adopting a solvent method, and the operation process is high in safety; and 3, the method has few post-treatment procedures and is environment-friendly.

Description

Technical Field

[0001] The invention belongs to the field of waste silk recycling and reuse, and particularly relates to a method for removing silicone oil remaining in spandex. Background Art

[0002] The wide application of spandex is well known to everyone. After the spandex is formed into yarn through the spray hole, silicone oil must be attached to its surface to facilitate the next spinning process. However, some waste yarns will inevitably be generated in the high-temperature spinning process. Silicone oil has been attached to the surface of these waste yarns. The presence of these silicone oils will affect the redissolution of spandex - the high-temperature spinning process. The residual silicone oil will decompose into silica at high temperature and clog the spray hole, affecting the spinning effect and industrial efficiency.

[0003] The current method for dealing with residual silicone oil in spandex waste is to use steam stripping. Steam is introduced into the spandex waste in a closed container, and the residual silicone oil is discharged along with the steam. However, a small amount of about 1.5% of silicone oil will still adhere to the spandex, and the discharged steam also contains silicone oil. Part of the silicone oil in the water after condensation will emulsify, causing additional costs for wastewater treatment.

[0004] In summary, in the existing industrial treatment process, wastewater containing silicone oil is produced during the removal of silicone oil, resulting in high costs and high energy consumption for wastewater treatment. Summary of the invention

[0005] The purpose of the invention is to provide a method for removing silicone oil remaining in spandex to solve the problems in the prior art.

[0006] The present invention is achieved through the following technical solution: a method for removing silicone oil remaining in spandex, characterized in that: S1: Place the spandex into a closed ultrasonic cleaning machine, pour in the solvent and make sure the solvent level completely submerges the spandex; S2: Starting an ultrasonic cleaning machine for cleaning, after cleaning, filtering the spandex containing the solvent to remove the solvent; S3: Put spandex into a vacuum tank, heat it up and evacuate it; S4: After stopping the vacuuming, slowly remove the vacuum and open the vacuum tank to take out the spandex.

[0007] Wherein: in step S1, the solvent is n-heptane or isooctane.

[0008] Wherein: in step S1, the mass of the solvent is 3-5 times the mass of the spandex.

[0009] Wherein: in step S2, the ultrasonic cleaner is turned on for a duration of more than 30 minutes.

[0010] Wherein: in step S3, after the vacuum tank is heated to 70°C-100°C, the vacuum pump is turned on until the vacuum degree in the vacuum tank is 0.07Mpa-0.09Mpa, the vacuum pump is turned off, and the vacuum pump is turned on again after the vacuum degree decreases, and the cycle is repeated several times until the vacuum degree does not decrease within 1 hour.

[0011] The advantages of the present invention are: The method of the present invention has the following advantages: 1. High silicone oil removal rate and little residual silicone oil; 2. The solvent method is used to remove silicone oil, and the operation process is highly safe; 3. The method has few post-processing steps and is environmentally friendly. DETAILED DESCRIPTION

[0012] The present invention provides a method for removing silicone oil remaining in spandex, which comprises the following steps: S1: Put spandex (referring to spandex waste, the same below) into a closed ultrasonic cleaning machine, pour in the solvent and make the solvent liquid surface completely immerse the spandex; at this time, the mass of the solvent is 3-5 times the mass of the spandex; S2: Start the ultrasonic cleaning machine for cleaning for more than 30 minutes (usually 30-90 minutes). After cleaning, remove the solvent from the spandex containing the solvent by filtering; S3: Put spandex into a vacuum tank, heat it up and evacuate it; S4: After stopping the vacuuming, slowly remove the vacuum and open the vacuum tank to take out the spandex.

[0013] Preferably: in step S3, the vacuum tank is first heated to 70°C-100°C, and then the vacuum pump is turned on until the vacuum degree in the vacuum tank is 0.07Mpa-0.09Mpa, the vacuum pump is turned off, and the vacuum pump is turned on again when the vacuum degree drops to 0.06Mpa, and the cycle is repeated 2-5 times until the vacuum degree is maintained at 0.07Mpa-0.09Mpa and no longer decreases within 1 hour.

[0014] Preferably: in step S1, the solvent is n-heptane or isooctane.

[0015] The present invention is further described below by means of specific embodiments: Example 1: Under the condition of ventilation kitchen and ventilation, use a 2-liter ultrasonic cleaning machine, weigh 400g spandex and put it into the tank of the ultrasonic cleaning machine, add 1200ml of n-heptane, cover the lid, and start the ultrasonic cleaning machine in a sealed state to keep cleaning for 30 minutes. After cleaning, take it out and remove part of the solvent by manually tightening the fiber, then put it into a filter press to remove most of the solvent, take it out and put it into a vacuum tank, raise the temperature in the vacuum tank to 90°C, turn on the vacuum pump until the vacuum degree is 0.09Mpa and stop, when the vacuum degree is reduced to 0.06-0.07Mpa, turn on the vacuum pump to 0.09Mpa, circulate until the vacuum degree no longer changes significantly after 20 minutes, slowly remove the vacuum, and take out the spandex. And take samples of the treated spandex to measure the silicone oil content.

[0016] The silicone oil content of this embodiment was detected to be reduced from 4.5% before treatment to 1.02%; Embodiment 2: The difference from Embodiment 1 is that the ultrasonic cleaning machine is turned on and the cleaning is maintained for 50 minutes.

[0017] After sampling and testing, the spandex treated in Example 2 showed that the silicone oil content was reduced to 0.50%; Example 3: The steps in Example 1 were repeated, except that isooctane was used as the solvent. After the treated spandex was sampled and tested, the silicone oil content was reduced to 0.83%; Example 4: The steps in Example 2 were repeated, except that isooctane was used as the solvent. After sampling and testing of the treated spandex, the silicone oil content was reduced to 0.31%.

[0018] In summary, the silicone oil content of the spandex treated by this method is greatly reduced, which greatly improves the spinning effect of the regeneration process, while avoiding the treatment of a large amount of wastewater and improving environmental protection. The used solvent can be reused after distillation, and the heavy component of the bottom of the tower is the silicone oil component, which can also be reused. There is no discharge of three wastes in the whole process.

Claims

1. A method for removing silicone oil remaining in spandex, characterized in that: The steps include: S1: Place the spandex into a closed ultrasonic cleaning machine, pour in the solvent and make sure the solvent level completely submerges the spandex; S2: Starting an ultrasonic cleaning machine for cleaning, after cleaning, filtering the spandex containing the solvent to remove the solvent; S3: Put spandex into a vacuum tank, heat it up and evacuate it; S4: After stopping the vacuuming, slowly remove the vacuum and open the vacuum tank to take out the spandex.

2. A method for removing silicone oil remaining in spandex according to claim 1, characterized in that: In step S2, the ultrasonic cleaner is turned on for a duration of more than 30 minutes.

3. A method for removing silicone oil remaining in spandex according to claim 1, characterized in that: In step S3, after the vacuum tank is heated to 70°C-100°C, the vacuum pump is turned on until the vacuum degree in the vacuum tank is 0.07Mpa-0.09Mpa, the vacuum pump is turned off, and the vacuum pump is turned on again after the vacuum degree decreases. This cycle is repeated several times until the vacuum degree does not decrease within 1 hour.

4. A method for removing silicone oil remaining in spandex according to claim 1, characterized in that: In step S1, the solvent is n-heptane or isooctane.

5. The method for removing silicone oil remaining in spandex according to claim 1, characterized in that: In step S1, the mass of the solvent is 3-5 times the mass of the spandex.