Difference and application comparison between spray and plate frame polyaluminum chloride

2025-11-24

Spray-dried polyaluminum chloride (PAC) and plate-and-frame polyaluminum chloride (PAC) are two Water Treatment flocculants produced using different processes. The main differences are as follows:

I. Production Process and Product Form

Spray-dried PAC

Process: Liquid raw materials are pressure filtered and then atomized and dried at high temperature in a spray drying tower to form an extremely fine powder.

Form: White or light yellow ultrafine powder, uniform in size, porous, and dissolves quickly.

Plate and Frame PAC

Process: Liquid raw materials are separated into solid and liquid phases using a plate and frame filter press, then dried and pulverized using a drum dryer.

Form: Yellow or yellowish-brown solid powder/granules, with relatively coarse particles.

Ⅱ、 Performance and Effect Comparison

Index	PAC PAC spray	Plate and frame PAC
Alumina content	Higher (28%-30%)	High (26%-30%)
Water-insoluble matter	≤0.3% (low impurities)	≤1.5% (slightly higher)
Dissolution rate	Extremely fast (porous structure, easily soluble)	Slower
Flocculation effect	Large and dense flocs settle quickly, resulting in low turbidity in the effluent.	Flocs form quickly, but sedimentation is relatively slow.
Applicable pH range	5.0-9.0 (wider)	5.0-9.0
Low temperature adaptability	Stable (remains highly efficient even at low temperatures)	generally

III. Application Scenarios

Spray PAC:

Drinking Water Treatment: Due to its low impurity content and high safety, it complies with national standard GB15892-2020.

High-precision applications: Such as papermaking, pharmaceutical, and food industries.

Plate and frame PAC:

Industrial wastewater treatment: Such as dyeing, coal washing, and metallurgical wastewater.

Domestic sewage treatment: Low cost, suitable for large-scale applications.

IV. Economic Efficiency and Operation

Dosage: Spray-applied PAC requires approximately 50% less dosage than plate-and-frame PAC, especially for highly polluted water.

Cost: Spray-applied PAC is more expensive (approximately 1650-2500 RMB/ton), while plate-and-frame PAC is more economical (approximately 880-1650 RMB/ton).

Ease of Operation: Spray-applied PAC dissolves quickly and does not clump, reducing the labor intensity for workers.

V. Selection Recommendations

Spray PAC: Suitable for drinking water, low-temperature, low-turbidity water, and high-purity applications.

Panel/Frame PAC: Suitable for industrial wastewater and projects with limited budgets.

Note: Actual selection requires a small-scale test based on a water quality report.