Polyacrylamide (PAM) produced by Chinese manufacturers is the most widely used organic polymeric flocculant and clarifier in the field of industrial wastewater treatment.
PAM works through a triple mechanism of charge neutralization, adsorption bridging, and net-like sweeping. This achieves rapid destabilization, coagulation, sedimentation, and deep clarification of suspended colloids and fine particulate matter. PAM is widely used in solid-liquid separation, pretreatment, advanced treatment, and sludge dewatering.
As industries upgrade towards resource utilization, low carbon emissions, and intelligent processes, novel modified PAM, coupled processes, and intelligent dosing technologies have become core supports for treating highly challenging industrial wastewater.
1. Working Principle
- Charge Neutralization: Neutralizes the surface charge of colloids, disrupting the double-layer structure and rapidly destabilizing stable pollutants;
- Adsorption Bridging: Long-chain molecules simultaneously adsorb multiple particles, forming dense, high-sedimentation-performance flocs;
- Net-like Sweeping: The flocs trap fine impurities during sedimentation, achieving deep clarification.
2. Product Types and Operating Conditions
- Anionic (APAM): Negatively charged, suitable for neutral/alkaline wastewater with predominantly inorganic suspended solids, used in mineral processing, sand washing, steelmaking, and electroplating.
- Cationic (CPAM): Positively charged, suitable for wastewater containing organic colloids and negatively charged pollutants, used in printing and dyeing, pharmaceuticals, food processing, and sludge dewatering.
- Nonionic (NPAM): Electroneutral, resistant to strong acids, suitable for acidic mine water and special chemical wastewater.
- Amphoteric (AmPAM): Bipolar charged, suitable for complex mixed wastewater with large fluctuations in water quality, used in oil fields and fine chemicals.
3. Typical Industrial Application Cases
- Mining/Sand Washing Wastewater (APAM): APAM+PAC combined, dosage 3~5g/ton, effluent turbidity ≤5NTU, reuse rate ≥90%.
- Dyeing/Chemical Wastewater (CPAM): Dense, unbroken flocs, sedimentation speed increased 5~10 times, decolorization rate ≥95%.
- Electroplating/Circuit Board Wastewater (chelated APAM): Heavy metal effluent ≤0.05mg/L, sludge reduction 60%.
- Food/Pharmaceutical Sludge Dewatering (CPAM): Sludge cake moisture content ≤60%, clear filtrate, significantly reduced treatment costs.
- Acidic Mine Wastewater (NPAM): Stable flocculation in strongly acidic environments, suspended solids removal rate ≥90%.
4. Standardized Application Process
- Solution Preparation: Concentration 0.1%~0.3%, dissolve at room temperature (10~40℃), stir at low speed for 30~60 minutes.
- Dosage Specifications: Add PAC first, then PAM, to the flocculation reaction tank.
- Dosage Control: 1~10g/ton of wastewater, in small amounts multiple times to avoid colloid restabilization.
5. Technical Advantages
Highly efficient clarification, low dosage, low sludge production, wide adaptability, and can be coupled with new process upgrades.
6. Storage, Transportation, and Operation Specifications
Store in a sealed, dry, and cool place. Dry addition is strictly prohibited. Take necessary safety precautions during operation.
7. Latest Research Progress (2024-2026)
- PAM Technology Innovation: Iteration of water-in-water type, heavy metal chelation type, and ultra-high molecular weight products; AI-powered intelligent dosing reduces costs by 20-40%;
- Coupled New Processes: PAM + magnetic flocculation, electrocoagulation, membrane separation, and evaporation, supporting zero emissions;
- Industry Frontiers: Synthetic bio-enhanced, advanced oxidation, low-carbon ZLD, and digital twin intelligent operation and maintenance;
- High-end Applications: Lithium recovery rate > 95% in lithium battery wastewater, COD compliance in coking wastewater, and resource utilization of high-salinity wastewater.