Why PAC Quality Matters
Not all PAC is created equal. Substandard PAC can lead to poor coagulation, high residual aluminum in treated water, and regulatory non-compliance. Here are the key quality parameters every buyer should check.
1. Al2O3 Content (Alumina Percentage)
This is the single most important indicator of PAC quality. Higher Al2O3 content means more active coagulant per kilogram of product. Drinking water grade should have at least 28% Al2O3. Values below 26% suggest adulteration or poor manufacturing.
2. Basicity
Basicity indicates the degree of polymerization. Higher basicity (60-85%) generally means better coagulation performance and less pH depression. However, very high basicity (above 90%) can reduce shelf stability.
3. Water Insoluble Matter
This indicates impurities and manufacturing quality. Drinking water grade should be below 0.6%. Higher values mean more sludge and potential filter clogging.
4. Heavy Metal Content
Critical for drinking water applications. Key limits per WHO guidelines:
- Arsenic: under 5 mg/kg
- Lead: under 10 mg/kg
- Cadmium: under 2 mg/kg
- Mercury: under 1 mg/kg
- Chromium: under 10 mg/kg
5. pH of 1% Solution
Should be between 3.5 and 5.0. Values outside this range may indicate manufacturing issues or product degradation.
6. Physical Appearance
Drinking water grade PAC should be a uniform yellow to light yellow powder. Dark brown color or inconsistent granules suggest quality issues.
Quick Quality Check at Receiving
- Check COA against specification sheet
- Visual inspection for color uniformity
- Jar test with your source water
- Measure pH of 1% solution
- Compare settling time against benchmark
HydroChemix provides full COA and third-party testing with every shipment. Contact us for product samples and quality documentation.