Differences Between Anionic and Cationic PAM

2025-10-08

Polyacrylamide (PAM) is a widely used flocculant in wastewater treatment, available in anionic PAM and cationic PAM types.

Anionic PAM is suitable for wastewater with high suspended solids and positive charges, such as mining wastewater, papermaking effluent, and textile dyeing wastewater.

Cationic PAM is ideal for organic-rich wastewater with negative charges, such as municipal sewage, food industry wastewater, pharmaceutical effluent, and slaughterhouse wastewater.

How to Select Polyacrylamide for Wastewater Plants

Municipal wastewater plants: Use cationic PAM for better sludge dewatering.

Industrial plants (textile, paper, mining): Use anionic PAM to remove suspended particles.

Food factories and slaughterhouses: Cationic PAM is more effective for organic pollutants.

High oil content wastewater: Often requires a combination of cationic PAM with inorganic coagulants like PAC.

Risks of Incorrect PAM Usage

1. Poor flocculation, resulting in turbid water.

2. Overdosing, leading to waste and possible secondary pollution.

3. High sludge moisture content, increasing disposal costs.

4. Pipe clogging and reduced system efficiency.

FAQ

Q1: How to distinguish anionic PAM from cationic PAM?
A1: Anionic PAM is for inorganic wastewater, while cationic PAM is for organic wastewater.

Q2: What determines the selection of polyacrylamide in wastewater treatment?
A2: Mainly the composition, charge characteristics, and industry type of the wastewater.

Q3: What happens if the wrong PAM type is used?
A3: It may cause poor flocculation, higher costs, and non-compliance with discharge standards.

Q4: Can PAM be combined with other chemicals?
A4: Yes, it is often used with PAC or iron salts to improve efficiency.

Q5: How is the PAM dosage determined?
A5: By laboratory tests and on-site adjustments according to wastewater characteristics.