Printing and dyeing factories often use polyacrylamide (PAM) in the production process.

The following is its specific application in printing and dyeing factories and other related content: Application function

Wastewater treatment flocculation and sedimentation: Printing and dyeing wastewater contains a large amount of pollutants such as dyes, slurries, and additives, and the water quality is complex. Polyacrylamide can condense the suspended particles and colloidal substances in the wastewater into larger flocs through adsorption bridging and electrical neutralization, accelerate precipitation, thereby achieving solid-liquid separation, removing most of the suspended matter and some soluble pollutants in the wastewater, and reducing the turbidity and chemical hydrogen demand (COD) of the wastewater

Sludge dehydration: In the sludge treatment link of printing and dyeing wastewater treatment, polyacrylamide can improve the dehydration performance of the sludge, making it easier to separate the water in the sludge, forming a mud cake with a higher dryness, which is convenient for subsequent sludge disposal and transportation.

Thickening of printing and dyeing auxiliaries: As a printing thickener, it can increase the viscosity of the printing paste, so that the paste maintains good stability and rheological properties during the printing process, prevent the paste from flowing and seeping, ensure the clarity and accuracy of the printed pattern, and help achieve fine printing and multi-color overprinting. Dispersion: It helps the dye to be evenly dispersed in the printing and dyeing liquid, prevents the aggregation and precipitation of dye particles, and enables the dye to be evenly in contact with the fabric fiber, improves the uniformity and color fastness of dyeing, and avoids problems such as uneven dyeing and color spots. Color fixation: It can improve the binding force between the dye and the fabric to a certain extent, play a color fixation role, reduce the shedding of the dye during the washing process, and improve the color fastness of the printing and dyeing products, especially for some reactive dyes, direct dyes, etc., which can effectively improve their fixation rate on the fabric.

Selection considerations

Water quality characteristics: The water quality of printing and dyeing wastewater varies depending on the printing and dyeing process and the dyes used. If the wastewater is alkaline and contains more anionic pollutants, cationic polyacrylamide is selected to achieve better flocculation effect by utilizing the electrostatic attraction between its cationic groups and cationic pollutants: nonionic or cationic polyacrylamide is more suitable for dry acidic wastewater or wastewater containing more nonionic pollutants.

Dye type: If the printing and dyeing factory mainly uses anionic dyes such as reactive dyes and direct dyes, anionic or nonionic polyacrylamide can be given priority in wastewater treatment and printing and dyeing auxiliaries to avoid charge conflict with the dye; while for the use of cationic dyes, cationic polyacrylamide can be selected to help improve the adsorption and fixation effect of the dye. Process requirements: In the printing process, screen printing requires color paste with higher viscosity, and anionic polyacrylamide with higher molecular weight and better thickening effect can be selected; digital printing has higher requirements on the fluidity and permeability of the color paste, and generally nonionic or zwitterionic polyacrylamide with moderate molecular weight and good fluidity is selected.

Hengfeng is committed to providing high-quality water treatment solutions and technical services for the selection and on-site application of printing and dyeing wastewater. Looking forward to your consultation