Application Comparison Of Solid And Liquid Polyaluminum Chloride

2025-12-09

Solid and liquid polyaluminum chloride (PAC) are two distinct physical forms of the same chemical substance, widely used as flocculants in Water Treatment. They differ significantly in application methods, transportation, cost, and storage. The following is a detailed comparative analysis:

Ⅰ.Main Differences

contrast dimension	Solid polyaluminum chloride	Liquid polyaluminum chloride
Form and Packaging	White or pale yellow powder, usually packaged in 25kg woven bags	Yellowish to brownish liquid, requires specialized tankers for transportation
Transportation methods and costs	It can be transported by ordinary trucks, which is convenient and low-cost; it is suitable for long-distance distribution.	Specialized tankers are required for transportation, resulting in high unit transportation costs (approximately 2–3 tons of liquid per ton of solid), and are typically economically viable only for deliveries within a 100-kilometer radius.
quality guarantee period	Long shelf life, up to 1 year	The shelf life is short, usually six months.
preconditioning	It must be dissolved into a liquid before use, requiring solvent preparation equipment and calculated ratios, which increases labor and operational complexity.	It can be added directly without dilution, making it more convenient to use and saving labor.
effective content	The effective component (Al2O3 content) is higher after drying, and the processing efficiency is relatively stronger.	High Water Content, low concentration of active ingredients, but low price
price	The unit price is high, but the concentration is high, so it may be more economical to convert based on the actual usage.	The unit price is low, but the actual effective ingredient is less because it contains a lot of water, and the comprehensive cost is higher when transported over long distances

Ⅱ.Summary of Advantages and Disadvantages

✅ Solid polyaluminum chloride

Advantages: low transportation cost, suitable for long-distance distribution; stable storage, long shelf life; high content of active ingredient per unit, strong processing ability.

Disadvantages: It needs to be dissolved before use, which increases the equipment investment and labor cost; the operation process is complicated, and there may be problems of uneven dissolution or residue.

✅ Liquid polyaluminum chloride

Advantages: Direct use, easy to add, high degree of automation; good solubility, fast reaction speed, uniform mixing; low initial purchase price.

Disadvantages: The transportation is dependent on tank car, the cost is high, the scope of application is limited; the shelf life is short, the sedimentation or deterioration is easy; the actual carrying of the effective ingredients is less, the "cost performance" may not be as good as the solid.

Ⅲ.How to choose?

The selection of solid or liquid polyaluminum chloride should be determined based on a comprehensive evaluation of practical application scenarios, treatment scale, transportation distance, and management capabilities.

usage scenario	Recommended type	account
Large-scale water treatment plant, long-term stable operation, equipped with chemical dissolution devices	✅ solid body	Low overall cost, easy to store, suitable for large-scale application
Small-scale wastewater treatment plants, temporary projects, and lack of specialized equipment	✅ liquid	Easy to use and requires no additional system configuration
More than 100 km from the supplier	✅ solid body	High cost of liquid transportation, not economical
Local supply, small volume, frequent use	✅ liquid	Reduce steps and improve efficiency

📌 Important note: Regardless of the formulation used, the substance must be added in liquid form before entering the treatment system. The key considerations are whether on-site dissolution conditions are available and an assessment of overall operational costs.

Conclusion

From the development trend, liquid polyaluminum chloride is widely used in local area because of its convenience.

However, from the perspective of economy and versatility, solid polyaluminum chloride (PAC) remains the predominant choice, particularly for medium to large-scale water treatment projects.

Users should choose the appropriate method according to their own conditions and avoid wasting transportation or using resources because of cheapness.