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Supercritical Fluid Dyeing

Supercritical CO2 Fluid Dyeing Equipment & Machine

Supercritical CO2 Fluid Dyeing Equipment


Supercritical Fluid Dyeing (SFD), also known as Waterless Dyeing.It is a new dyeing technology with good prospects.

Supercritical dyeing uses carbon dioxide as a medium. The solubility of supercritical carbon dioxide in organic matter varies with solute polarity, molecular weight, density, etc., and it is easy to dissolve organic substances with low polarity or weak polarity and small molecular weight.

Supercritical Fluid Dyeing Machine
Supercritical Fluid Dyeing Machine
Supercritical CO2 Fluid Dyeing Equipment
Supercritical CO2 Fluid Dyeing Equipment

Disperse dyes generally have a weak molecular polarity and a low molecular weight, and are therefore readily soluble in supercritical carbon dioxide. The dye molecules dissolved in supercritical carbon dioxide are scattered and scattered, so the dyeing in this state, the dye in the dye bath is active, can reach the surface of the fiber quickly, and then easily penetrate into the fiber to achieve the purpose of dyeing the dye.


The viscosity of the gas formed under supercritical conditions is low, the dye can be dissolved automatically and has high diffusivity; the solubility of the dye in the carbon dioxide fluid increases with the increase of the density of the fluid, and the density of carbon dioxide is controlled by pressure and temperature. Thereby controlling the solubility of the dye in the carbon dioxide fluid, increasing the temperature to reduce the fluid density and the number of dyes in the solution, and promoting the diffusion of the dye into the fiber, so the system control parameters can be adjusted more quickly than the conventional phase process.

The supercritical fluid has small viscosity, large relative density, large diffusion coefficient, low tension, excellent mass transfer performance, and low glass transition temperature of supercritical CO2. Due to these characteristics, supercritical CO2 has a good carrier effect and is suitable as a dye intermediate. Moreover, in the CO2 under supercritical conditions, the fabric will expand significantly, which is beneficial to the dyeing of the dye. Therefore, the technique is particularly suitable for hydrophobicity such as polyester fiber fabric and dense textured fabric, less dyeing genes, and poor moisture absorption performance. It is a small cloth that is puffed in water and is difficult to dye with a fabric dyed with a hydrophilic dye.

Supercritical Fluid Dyeing Machine
Supercritical Fluid Dyeing Machine

The supercritical dyeing process requires no additives, carbon dioxide is non-toxic and can be recycled; residual dyes can be recycled in powder state, no waste water and waste, no need for dyeing and drying after dyeing, energy saving can be about 80%, the dyeing speed of the process It is several times faster than the traditional process and has high dyeing efficiency. The dyeing process does not produce pollutants, which fully reflects the concept of cleaner production. Supercritical fluid dyeing technology can solve the environmental pollution problems of the industry in the same way.

Supercritical dyeing characteristics:

Supercritical carbon dioxide has high surface tension, low viscosity and high diffusion coefficient, as well as the dissipability of disperse dyes. This new dyeing method is a challenge to traditional dyeing methods. The difference between supercritical dyeing and traditional dyeing is that

1. The entire process is completely free of water, so there is no wastewater treatment problem;

2, because there is no water, so the textile does not dry after the dyeing process, saving energy;

3, no need to add surfactants or other additives;

4. Generally speaking, the color is more vivid than the traditional process dyeing. Compared with the traditional dyeing, the dye and carbon dioxide are easy to recover. Under the same conditions, the dyeing temperature is lower than the conventional dyeing temperature;

5. The whole process is simpler than the traditional process;

6. It is suitable for dyeing materials that are difficult to dye with water dyeing, such as polylactic acid fiber.


  Due to the inherent characteristics of supercritical CO2, it is used as a dyeing medium, with less dye, better dyeing quality, greatly simplified process, short printing time, no need to add additives, especially suitable for dense textured fabrics and military resistance. Dyeing of the cloth with radiation.

Save dyes: the absorption rate of dyes can reach more than 90%, and the unused dyes can be easily recovered by separating them from CO2 gas;

Saving auxiliaries: Due to the excellent mass transfer characteristics of supercritical CO2, it is not necessary to add various surfactants such as dispersing agents, adhesive agents, suspending agents, etc. as in the conventional process.

Significant reduction process: This process eliminates the need for multiple rinsing and time-consuming drying processes, which will be completed in several steps, such as desizing, degreasing, dyeing and drying.

Printing and dyeing time is significantly shortened: the traditional dyeing process takes 2 hours, and the whole dyeing process takes about 3 to 5 days. The dyeing process using the supercritical CO2 process takes only 20 minutes, and all the dyeing and finishing processes can be completed in one day.

The dyeing quality is good: the dyeing with supercritical CO2 as the medium, the color fastness, the soaping fastness and the friction degree can reach 4 or even 5.

Cost saving: After rough calculation, the use of waterless dyeing technology can reduce the dyeing cost by 50% and the energy consumption by more than 60%. It can bring significant economic benefits to enterprises; at the same time, water-free dyeing cloth reduces the use of water resources of enterprises, greatly reduces the pollution to the environment, and completely solves the problem of sewage treatment in enterprises, so it adopts supercritical dyeing technology for enterprises. Come to far-reaching social benefits.


1. Volume: Dyeing tank: Volume 1L-500L, dye pot: Volume 0.5L-100L, Separation tank: Volume 600mL-250L, maximum design temperature 150°C

2. Pressure:

Dyeing kettle: maximum design pressure 50MPa

Dye kettle: maximum design pressure 50MPa

Separation kettle: maximum design pressure 20MPa

3. Design temperature:

Dyeing kettle: room temperature -150 ° C

Dye kettle: room temperature -150 ° C

Separation kettle: room temperature -85 ° C


Device size        

Dyeing tank effective volume          

Design Features



The most complete system configuration parameters are the most extensive, and are most widely used for supercritical dyeing and small-scale scientific research needs of various materials;

Process pipelines can be changed and expanded at any time according to user needs;

It is equipped with safety devices of various principles to protect the experimental operators, and the system is safe and reliable;

The device has excellent performance, which makes the operation simple and the experimental data is stable and reliable;

Use a variety of high-quality fittings to avoid cross-contamination of dyes, easy to clean, maintain, maintain and replace parts, suitable for laboratory test.

Pilot production


The unique design of the dyeing kettle structure, the feeding cloth and the dyeing work mode make the fabric dye evenly;

The process layout is scientific and reasonable, the operating parameters are designed and selected, the heat and mass transfer efficiency is high, and the energy consumption is low;

It is equipped with safety devices of various principles to protect the experimental operators, and the system is safe and reliable;

Uniquely designed quick-opening structure, good airtightness, simple and reliable operation;

Use a variety of high-quality fittings to avoid cross-contamination of dyes;

High self-control level, stable and reliable product quality and experimental data, suitable for industrial amplification to obtain design basis;

Industrial production


Because the project belongs to high-tech development, including high-pressure quick opening, pressure vessel, chemical machinery, system optimization and amplification, electrical instrumentation, automatic control and other professional technologies, it is necessary to carry out process research, dye development and equipment structure for various fabrics. The design will be based on the actual needs of the customer to design a specific process route and configuration plan, and then industrialized amplification implementation.

The supercritical dyeing complete set includes dyeing system, separation system, pressurization system, heat exchange system, heating system, refrigeration system, safety system, electrical system, instrument automatic control system, data transmission remote monitoring system, recovery system, inflation system, pipeline Various functional systems such as valves and auxiliary systems, each set is designed according to the process route and operating parameters of different reaction materials. The specific configuration and process plan will be adjusted according to the different needs of customers to achieve the most Good value for money.