What is Poly Aluminium Chloride (PAC)?

Poly Aluminium Chloride (PAC) is a widely used inorganic polymer coagulant with the chemical formula Aln(OH)mCl3n−mAl_n(OH)_mCl_{3n-m}Aln​(OH)m​Cl3n−m​. It is produced by the controlled hydrolysis of aluminium chloride and is characterized by its high polymerization degree and positive charge density. PAC appears as a yellowish or off-white powder or liquid solution and is highly soluble in water.

PAC is primarily used as a coagulant and flocculant in water and wastewater treatment to remove suspended solids, turbidity, organic matter, and heavy metals. It works by neutralizing the negative charges on colloidal particles, allowing them to aggregate into larger flocs that can be easily separated by sedimentation or filtration.

Compared to traditional coagulants like alum or ferric chloride, PAC offers several advantages, including higher efficiency at lower doses, rapid settling rates, and less sludge production. Its performance is effective across a wide pH range and in both cold and warm water conditions.

Industrially, PAC finds extensive application not only in drinking water treatment but also in industrial wastewater treatment, paper manufacturing, dye removal, and sludge dewatering processes. It helps enhance water clarity and reduces the load on downstream filtration and disinfection.

Although PAC is generally safe when used as directed, concentrated solutions can be corrosive and may cause skin and eye irritation. Proper handling and protective equipment are recommended.

USES AND APPLICATIONS

INDUSTRIES

Poly Aluminium Chloride is widely applied in:

• Municipal drinking water treatment
• Industrial and municipal wastewater treatment
• Paper and pulp industry for wastewater clarification
• Dye and textile wastewater treatment
• Sludge conditioning and dewatering