A cashmere bio-based dyeing device

Abstract

The utility model belongs to textile printing and dyeing equipment technical field, concretely relates to a cashmere dyeing device suitable for adopting biological base dye. A cashmere biological base dyeing device, including pre-reduction unit, dyeing main part unit, dynamic balance unit, conveying pipeline unit. Pre-reduction unit is used for reducing dye into dyeing liquid, and dyeing main part unit is used for dyeing cashmere, and dynamic balance unit is located the upstream of dyeing main part unit, including mixing jar and pH sensor, and conveying pipeline unit includes the conveying pipeline for connecting pre-reduction unit and dynamic balance unit, the circulating pipeline for connecting dynamic balance unit and dyeing main part unit, and circulating pump is set up on circulating pipeline, and control valve is set up on circulating pipeline. The utility model can solve the contradiction between the alkaline reduction demand and the alkali-averse characteristics of cashmere faced by biological base dye in cashmere dyeing, effectively protect cashmere fibre quality while efficiently completing dyeing.

Description

Technical Field

[0001] This utility model belongs to the technical field of textile printing and dyeing equipment, specifically relating to a cashmere dyeing device suitable for using bio-based dyes. Background Technology

[0002] Cashmere fibers are highly prized for their softness, lightweight, and excellent warmth. However, the dense scaly structure on their surface and the inherent sensitivity of protein fibers to chemical environments make the dyeing process for cashmere extremely demanding. Traditional cashmere dyeing primarily uses acidic dyes, performed in an acidic bath. However, with the development of bio-based dyes (such as biomass indigo), their advantages in sustainability and environmental protection are becoming increasingly apparent. But these dyes typically require reduction to a water-soluble leuco form in an alkaline environment before they can be applied to the fibers, which fundamentally contradicts the alkali-sensitive nature of cashmere fibers.

[0003] In existing technologies, mechanical stirring is often used to promote uniform contact between dye and fiber during the dyeing process. For example, Chinese utility model patent CN223226320U discloses an acid dyeing device for cashmere. This device includes a dyeing tank, a receiving tank, a liquid pushing assembly, and a connecting assembly. Its working principle is as follows: a motor drives a threaded rod to rotate, which in turn moves a moving plate and its linked slider and pusher plate, pushing the dye from the square column into the receiving tank. This impacts the cashmere fibers inside the tank and simultaneously rotates the receiving tank. The aim is to promote the mixing and adsorption of dye and cashmere fibers through liquid flow impact and tank rotation without directly mechanically stirring the cashmere.

[0004] However, analysis revealed that this existing technology is not suitable for dyeing cashmere with bio-based dyes:

[0005] This device is designed for dyeing with conventional acid dyes. The entire dyeing process is completed in a single dyeing tank. It is difficult to achieve precise online monitoring and automatic control of dye addition, pH adjustment, oxidation process, etc., resulting in poor process reproducibility. Moreover, dye failure is easily caused during dye liquor transfer and dyeing, resulting in uneven dyeing or reduced color yield.

[0006] Therefore, there is an urgent need to develop specialized dyeing equipment suitable for bio-based dyes that can maximize the protection of cashmere fibers. Utility Model Content

[0007] To address the aforementioned problems, the purpose of this invention is to provide a cashmere bio-based dyeing device that aims to resolve the contradiction between the alkaline reduction requirements of bio-based dyes in cashmere dyeing and the alkali-sensitive nature of cashmere, thereby efficiently completing the dyeing process while effectively protecting the quality of cashmere fibers.

[0008] To achieve the above objectives, the technical solution of this utility model is as follows:

[0009] A cashmere bio-based dyeing device, comprising:

[0010] A pre-reduction unit, used to reduce dye into dyeing solution, includes a reduction vessel and a discharge valve disposed at the outlet of the reduction vessel;

[0011] The main dyeing unit, used for dyeing cashmere, includes a cylinder and a circulation pump;

[0012] A dynamic balancing unit, located upstream of the staining main unit, includes a mixing tank and a pH sensor;

[0013] The delivery pipeline unit includes a delivery pipeline for connecting the pre-reduction unit and the dynamic balancing unit, and a circulation pipeline for connecting the dynamic balancing unit and the staining main unit; the circulation pump is installed on the circulation pipeline, and a control valve is installed on the circulation pipeline.

[0014] As a further preferred embodiment of the present invention, the dynamic balancing unit further includes an acid injection port and an alkali injection port disposed on the mixing cylinder, an acid supply device and an alkali supply device respectively connected to the acid injection port and the alkali injection port, and a first metering pump and a second metering pump respectively disposed on the outlet of the acid supply device and the alkali supply device.

[0015] As a further preferred embodiment of this utility model, a buffer cylinder is connected in series on the conveying pipeline, and a metering valve is provided on the discharge port of the buffer cylinder.

[0016] As a further preferred embodiment of this utility model, it also includes a water pipeline unit, which is used to supply water to the pre-reduction unit and the buffer tank through a first pipeline and a second pipeline, respectively.

[0017] As a further preferred embodiment of this invention, the water pipeline unit is further provided with a third pipeline for supplying water to the dyeing main unit.

[0018] As a further preferred embodiment of this invention, the reduction vessel and the buffer cylinder are respectively provided with a first protective gas interface and a second protective gas interface.

[0019] As a further preferred embodiment of this invention, an oxidation gas inlet is provided at the bottom of the cylinder.

[0020] As a further preferred embodiment of this invention, a delivery pump located upstream of the buffer cylinder is also connected in series on the delivery pipeline.

[0021] As a further preferred embodiment of this invention, it also includes a controller electrically connected to the pH sensor, the first metering pump, the second metering pump, and the control valve.

[0022] As a further preferred embodiment of this invention, the controller is also electrically connected to the delivery pump and the metering valve.

[0023] The beneficial effects of this utility model are:

[0024] This invention achieves physical isolation between the strong alkaline reducing environment of dyes and the neutral dyeing environment of cashmere fibers by setting up independent pre-reduction units and dyeing main units. This fundamentally solves the problem of incompatibility between bio-based dyes (such as indigo) dyeing processes and the characteristics of cashmere fibers. Moreover, the dyeing process is carried out in a controllable neutral bath, avoiding hydrolytic damage to cashmere proteins by alkali.

[0025] This invention uses a dynamic balancing unit to monitor and automatically adjust the pH value of the dye bath in real time, ensuring that it is always in the optimal neutral range for cashmere safety, thus better maintaining the natural elasticity and soft feel of cashmere fibers. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of this utility model.

[0027] Figure description: Pre-reduction unit 100, dyeing main unit 200, dynamic balancing unit 300, buffer tank 500, water pipeline unit 600;

[0028] Discharge valve 110, conveying pump 120;

[0029] Circulating pump 210;

[0030] pH sensor 310, acid supply device 320, alkali supply device 330, first metering pump 340, second metering pump 350;

[0031] Delivery pipeline 41, circulation pipeline 42, control valve 430;

[0032] Metering valve 510;

[0033] First pipeline 61, second pipeline 62, third pipeline 63;

[0034] First protective gas interface 71, second protective gas interface 72, oxidation gas interface 73. Detailed Implementation

[0035] In the description of this utility model, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use, or the orientation or positional relationship that is commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0036] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0037] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; 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 a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0038] like Figure 1 As shown, this embodiment provides a cashmere bio-based dyeing device, which is particularly suitable for dyeing cashmere fibers with biomass indigo dye.

[0039] The device mainly includes: a pre-reduction unit 100, a dyeing main unit 200, a dynamic balancing unit 300, and a delivery pipeline unit and a water pipeline unit 600 connecting them.

[0040] The main connections of the device are as follows: the pre-reduction unit 100 is connected to the downstream via a conveying pipeline 41. A conveying pump 120 and a buffer cylinder 500 are connected in series on the conveying pipeline 41. The outlet of the buffer cylinder 500, after passing through a metering valve 510, can be connected to the inlet of the dyeing main unit 200 (e.g., its auxiliary cylinder or directly into the main circulation). The dyeing main unit 200 consists of a circulating pump 210, a circulating pipeline 42, a control valve 430, a cylinder, and a yarn frame installed inside the cylinder, forming a closed dye liquor circulation loop. The dynamic balancing unit 300 is directly connected in series to the circulating pipeline 42. The water pipeline unit 600 is connected to the reduction vessel of the pre-reduction unit 100 via a first pipeline 61, to the buffer cylinder 500 via a second pipeline 62, and to the cylinder of the dyeing main unit 200 via a third pipeline 63. The reduction vessel and the buffer cylinder 500 are respectively equipped with a first protective gas interface 71 and a second protective gas interface 72 at their tops. The bottom of the cylinder 220 is equipped with an oxidation gas interface 73. The controller is connected to all power and actuator components, including pH sensor 310, delivery pump 120, metering valve 510, circulation pump 210, control valve 430, first metering pump 340, and second metering pump 350, via signal lines.

[0041] In this embodiment, the pre-reduction unit 100 is a dye activation center used to reduce the dye into a dyeing solution. It includes a sealed reduction vessel with a stirring and temperature control jacket. A feeding port is located at the top of the vessel, and a first protective gas interface 71 is also located at the top to receive a protective gas (such as nitrogen). An outlet is located at the bottom of the vessel, and a discharge valve 110 is installed on the outlet. Its function is to reduce water-insoluble biomass indigo dye powder into a soluble yellow-green indigo leuco concentrate under strongly alkaline conditions (such as the addition of NaOH) and a reducing agent (such as sodium hydrosulfite or through electrochemical methods). The entire process can be carried out under nitrogen protection to prevent oxidation of the reduction product. Stirring ensures uniform reaction, and the temperature control jacket maintains the reaction temperature within the optimal range of 50-60°C.

[0042] The dyeing unit 200 is used for dyeing cashmere and includes a pressure-resistant, sealed cylinder containing a yarn rack capable of holding multiple cashmere yarn packages. The circulation pump 210 provides the pressure and flow rate required to force the dye liquor to penetrate the tightly packed yarn. The control valve 430 is preferably an automatic reversing valve, which, according to a controller program, periodically changes the flow direction of the dye liquor in the circulation pipeline 420, achieving alternation between "forward circulation" (dye liquor penetrating the yarn packages from the outside in) and "reverse circulation" (dye liquor penetrating from the inside out), ensuring uniform dyeing.

[0043] The dynamic balancing unit 300 is connected in series at both ends in the circulation pipeline 420, ensuring that all circulating dye solutions must flow through it. Located upstream of the main dyeing unit 200, it includes a mixing tank and a pH sensor 310. The probe of the pH sensor 310 extends into the flow path within the mixing tank 360 to detect the pH value of the dye solution in real time. The mixing tank is equipped with an acid inlet and an alkali inlet, which are connected to the acid supply device 320 and the alkali supply device 330 respectively via pipelines. A first metering pump 340 and a second metering pump 350 are installed on the pipelines. When pH adjustment is required, the controller instructs the corresponding metering pump to start, injecting acid (such as dilute acetic acid) or alkali (such as dilute sodium carbonate solution) into the dye solution, quickly restoring the pH value to the set neutral point (such as pH 6.5~7.0) without stopping the circulation.

[0044] The delivery pipeline unit includes a delivery pipeline 41 for connecting the pre-reduction unit 100 and the dynamic balancing unit 300, and a circulation pipeline 42 for connecting the dynamic balancing unit 300 and the dyeing main unit 200; a circulation pump 210 is installed on the circulation pipeline 42, and a control valve 430 is installed on the circulation pipeline 42.

[0045] A buffer cylinder 500 is also connected in series on the delivery pipeline 41. The buffer cylinder 500 is a sealed container with a second protective gas interface 72. Its installation height is usually lower than the outlet of the reduction vessel and higher than its own outlet (at the metering valve 510), which facilitates gravity-assisted delivery and venting. Its function is to safely receive the leucocyanide concentrate from the pre-reduction unit 100, acting as a "transfer station" or "pre-dilution station" to prevent the concentrate from directly impacting the dyeing system.

[0046] A transfer pump 120 located upstream of the buffer tank 500 is also connected in series on the transfer pipeline 41. The transfer pump 120 provides power to pump the concentrate from the reduction vessel into the buffer tank 500 through the transfer pipeline 41.

[0047] During the transport process, nitrogen gas is introduced through the first protective gas interface 71 and the second protective gas interface 72 to form an inert atmosphere in the pipeline and buffer cylinder 500, thereby achieving "anti-oxidation transport".

[0048] Furthermore, a metering valve 510 is installed at the outlet of the buffer tank 500 to smoothly add the leuco concentrate into the circulating dyeing solution of the dyeing system.

[0049] The water piping unit 600 includes independent pipes (61, 62, 63) leading to the pre-reduction unit 100, the buffer tank 500, and the dyeing main unit 200, each controlled by a solenoid valve. It provides the required process water (cold or hot water) to each station.

[0050] Furthermore, the bottom of the dyeing main unit 200 is provided with an oxidation gas interface 73, which is connected to the workshop compressed air pipeline. After dyeing is completed, air is blown into the cylinder 220 to oxidize the indigo leuco pigment adsorbed on the cashmere into insoluble blue indigo, thus completing the color fixation.

[0051] The controller can be a commonly used device in the field (such as a PLC), and it is electrically connected to the pH sensor 310, the first metering pump 340, the second metering pump 350, the control valve 430, the transfer pump 120, and the metering valve 510. More specifically, the controller receives the real-time signal from the pH sensor 310, compares it with a preset process curve, and outputs commands to control the start, stop, and frequency of the first metering pump 340 and the second metering pump 350. It is also programmed to control the interlocking action of the transfer pump 120 and the metering valve 510, the start, stop, and speed of the circulating pump 210, the timed switching of the control valve 430, and the opening and closing sequence of the valves in the water and gas circuits, thereby achieving full-process automation.

[0052] The working process of this device is as follows:

[0053] S1. Close the discharge valve 110 and inject a certain amount of water into the reduction vessel of the pre-reduction unit 100 through the first pipeline 61, and add a calculated amount of caustic soda (NaOH) and biomass indigo dye.

[0054] S2. Open the first protective gas port 71 to introduce nitrogen to replace the air, start stirring and heating, add reducing agent (or start electrochemical reduction), and carry out the reduction reaction at 50~60℃ under nitrogen protection until a clear yellow-green leuco concentrate is obtained.

[0055] S3. Start the delivery pump 120 and turn on the nitrogen protection of the delivery pipeline 41 and the buffer cylinder 500.

[0056] S4. Open the discharge valve 110 to transfer the leucocyanide concentrate in the reduction vessel to the buffer tank 500 for temporary storage, and maintain a nitrogen atmosphere.

[0057] S5. Load the cashmere yarn into the bobbin of the dyeing main unit 200 and keep the bobbin sealed.

[0058] S6. Inject an appropriate amount of clean water into the cylinder through the third pipeline 63, start the circulation pump 210, and establish basic circulation.

[0059] S7. Slowly open the metering valve 510 at the bottom of the buffer tank 500 in proportion to steadily add the leuco concentrate into the circulating dyeing solution of the dyeing system. At the same time, add water to the system through the second pipeline 62 to achieve the process bath ratio.

[0060] S8, pH sensor 310 starts working. Because the concentrate is highly alkaline, the pH of the dye bath will rise. The controller immediately starts the first metering pump 340 based on the feedback, injecting dilute acetic acid into the mixing tank of the dynamic balancing unit 300. The acid solution mixes rapidly in the dye bath, accurately neutralizing and stabilizing the overall pH of the dye bath within the preset neutral range (pH 7.0±0.3).

[0061] S9 and circulating pump 210 operate continuously, while control valve 430 switches direction periodically according to a program, ensuring uniform penetration of the dye liquor into the yarn. The dyeing temperature is maintained at a safe level of 75-85℃ for cashmere by the temperature control system of the main dyeing unit 200. The dyeing time is set according to the required color depth (e.g., 30-60 minutes). During this period, the dynamic balancing unit 300 operates continuously to compensate for any factors that may cause pH fluctuations.

[0062] S10. After dyeing is completed, drain the dye solution. Inject clean water through the third pipe 63 and open the oxidation gas interface 73 to blow compressed air into the cylinder of the dyeing main unit 200. Circulate for a certain period of time to allow the leuco pigments on the cashmere to fully oxidize and turn blue.

[0063] S11. Proceed with standard post-treatment steps such as soap boiling, hot water washing, and cold water washing.

[0064] Through the above process, this utility model device successfully achieves efficient, high-quality, and low-damage dyeing of biomass indigo onto cashmere. The entire system has the advantages of clear structure and high degree of automation.

[0065] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A cashmere bio-based dyeing device, characterized in that: include: The pre-reduction unit (100) is used to reduce the dye into a dyeing solution, and includes a reduction vessel and a discharge valve (110) disposed on the discharge port of the reduction vessel. The dyeing main unit (200) for dyeing cashmere includes a cylinder and a circulation pump (210). A dynamic balancing unit (300), located upstream of the staining main unit (200), includes a mixing tank and a pH sensor (310). The delivery pipeline unit includes a delivery pipeline (41) for connecting the pre-reduction unit (100) and the dynamic balancing unit (300), and a circulation pipeline (42) for connecting the dynamic balancing unit (300) and the dyeing main unit (200); the circulation pump (210) is provided on the circulation pipeline (42), and the circulation pipeline (42) is provided with a control valve (430).

2. The cashmere bio-based dyeing device according to claim 1, characterized in that: The dynamic balancing unit (300) further includes an acid injection port and an alkali injection port provided on the mixing cylinder, an acid supply device (320) and an alkali supply device (330) respectively connected to the acid injection port and the alkali injection port, and a first metering pump (340) and a second metering pump (350) respectively provided on the outlet of the acid supply device (320) and the alkali supply device (330).

3. The cashmere bio-based dyeing device according to claim 1, characterized in that: A buffer cylinder (500) is connected in series on the conveying pipeline (41), and a metering valve (510) is provided on the outlet of the buffer cylinder (500).

4. The cashmere bio-based dyeing device according to claim 3, characterized in that: It also includes a water pipeline unit (600), which supplies water to the pre-reduction unit (100) and the buffer tank (500) through a first pipeline (61) and a second pipeline (62), respectively.

5. The cashmere bio-based dyeing apparatus according to claim 4, characterized in that: The water pipeline unit (600) is also provided with a third pipeline (63) for supplying water to the dyeing body unit (200).

6. The cashmere bio-based dyeing apparatus according to claim 3, characterized in that: The reduction vessel and the buffer cylinder (500) are respectively provided with a first protective gas port (71) and a second protective gas port (72).

7. The cashmere bio-based dyeing apparatus according to claim 1, characterized in that: An oxidation gas inlet (73) is provided at the bottom of the cylinder.

8. The cashmere bio-based dyeing apparatus according to claim 3, characterized in that: The delivery pipeline (41) is also connected in series with a delivery pump (120) located upstream of the buffer cylinder (500).

9. A cashmere bio-based dyeing apparatus according to claim 2, characterized in that: It also includes a controller electrically connected to the pH sensor (310), the first metering pump (340), the second metering pump (350), and the control valve (430).

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