Introduction to Printing and Dyeing Factory-Specific Polyacrylamide
Printing and dyeing factory-specific polyacrylamide is a composite polymer with versatile applications. It effectively clarifies coal washing water by enabling rapid agglomeration and settlement of fine particles in the water, thereby enhancing the recovery of sludge coal and achieving water conservation and pollution prevention. However, the disposal of sludge generated from printing and dyeing wastewater poses a significant challenge for manufacturers. Generally, printing and dyeing sludge contains a high proportion of inert materials, such as high sand content in sludge from denim garment washing and bleaching wastewater, with low levels of organics, pathogens, and thermal value. Additionally, compared to sludge from municipal wastewater treatment, printing and dyeing sludge typically contains higher concentrations of heavy metals. Due to variations in raw materials, product types, and processing methods used in the printing and dyeing industry, the sludge composition also differs. For instance, enterprises using sulfide dyes tend to have higher sulfide content in their sludge. Therefore, the selection and dosage of chemicals for treating printing and dyeing sludge must be tailored based on the sludge source, taking into account factors such as wastewater treatment capacity, sludge production, chemical availability, dosage rates, operating costs, and moisture content of the sludge cake, to ensure a practical and comprehensive approach suited to local conditions.
Specific Applications:
Printing and dyeing factory-specific polyacrylamide exhibits hygroscopicity, flocculation, adhesion, drag reduction, thickening, and excellent stability. Its molecules can bridge and adsorb suspended particles dispersed in solution, demonstrating a strong flocculating effect. Our polyacrylamide products are categorized into four series: anionic, cationic, and varying molecular weights and degrees of ionization. Given the scale limitations of domestic printing and dyeing factories, with wastewater volumes generally not exceeding 100,000 cubic meters per day, large-scale land-based natural drying or incineration facilities are impractical, especially in regions like Jiangsu and Zhejiang with rainy and humid climates. Instead, small-scale wastewater treatment plants are commonly used for treatment, where sludge undergoes initial conditioning followed by press dewatering. During the dehydration process, a substantial amount of flocculant is used as a sludge dewatering agent. Various flocculants, including aluminum sulfate, ferric chloride, ferrous sulfate, polyaluminum chloride, polysulfate aluminum, and polyacrylamide, are available, each with its specific application range, advantages, and disadvantages.
Usage Instructions:
Prepare a 0.01% to 0.03% concentration aqueous solution for use, preferably with neutral water free of saline impurities.
To dissolve, evenly sprinkle the polyacrylamide product into stirring water, controlling the stirring speed at 100 to 300 rpm. Mild heating (<60°C) can accelerate dissolution.
Adjust the pH of the treated liquid to optimize the effectiveness of the product (determine the optimal pH and product dosage through experimentation).
When adding the polyacrylamide solution, accelerate mixing with the treated liquid. Once flocculants form, reduce the stirring speed to facilitate floc growth and accelerated settlement.
Precautions:
Dissolution Temperature: The dissolution of polyacrylamide requires a certain temperature to expedite the process. However, excessively high temperatures can cause molecular chain breakage, reducing effectiveness. The optimal dissolution temperature range is 50-60°C.
Mixing Conditions: Avoid using excessively strong shear force during dissolution, as it can cause molecular chain breakage and impair effectiveness. Low-speed agitators, such as anchor, frame, and multi-layer paddle types, are preferable, operating at approximately 60 rpm. For transfer, avoid using high-speed centrifugal pumps; piston or diaphragm pumps are more suitable.
Uniform Dispersion and Feeding: Uniform dispersion is crucial for polyacrylamide dissolution. After starting the agitator, use a mechanical vibrating screen (with a mesh size of 10 mesh) for feeding to minimize the formation of large agglomerates or "fish-eye" particles, ensuring thorough dissolution and optimal performance.
Avoid Contact with Iron: In dissolution, mixing, transfer, and dosing systems, plastics, enamel, aluminum, stainless steel, and other materials are recommended.
This product offers a reliable solution for enhancing the efficiency and sustainability of printing and dyeing processes.
