Polyaluminium Chloride (PAC) in Water Treatment in Africa

Africa’s water sector is expanding fast – municipal supply, industrial wastewater, mine water and reuse. Polyaluminium chloride (PAC, CAS 1327-41-9) suits that environment well: it works across a wide pH range, is effective in cold water, forms flocs quickly and needs less pH correction than alum, which matters where alkalinity and chemical supply chains are constrained. This article looks at where PAC is used in African water treatment and what to specify when buying.

1. Why PAC suits African water projects

Wide pH window (roughly 5-9) – fewer pH swings when raw-water quality varies with season or source.
Works in cold water – important in southern African winters and in high-altitude sites.
Lower alkalinity consumption – less lime or caustic needed to hold pH, which cuts chemical spend and handling.
Fast, dense flocs – useful where clarifier capacity is limited and throughput matters.
Less sludge – lower sludge volume reduces dewatering and disposal cost.

2. Where it is used

Application	Role of PAC
Municipal drinking water	Primary coagulant for turbidity and colour removal (drinking-water grade)
Industrial wastewater	Coagulation ahead of flocculation and clarification
Textile and dyeing effluent	Colour and suspended-solids removal
Mine water and process water	Solids and turbidity removal before discharge or reuse
Paper and board mills	Retention and clarification

3. Grades for African projects

Grade	Al₂O₃ content	Use
Drinking-water grade (white / light)	Solid about 28-31%; liquid about 10-11%	Potable supply; tight heavy-metal limits
Industrial grade (yellow / pale yellow)	Solid about 28-30%; liquid about 10%	Wastewater, industrial and mining

The two numbers to confirm on any PAC quote are the Al₂O₃ content (what you are paying for) and the basicity (how pre-hydrolysed it is). Basicity typically runs about 40-80%; a higher basicity gives better performance in many waters but is not always the right choice – it depends on your water.

4. Dosing

As a starting point, PAC is dosed in the range of a few mg/L to a few tens of mg/L (as product or as Al₂O₃, depending on how the dose is quoted), always set by jar test on the actual water. Because PAC needs less pH correction, check your post-dose pH as well as turbidity when you optimise.

5. Packaging and delivery to Africa

Form	Packaging
Solid	25 kg bags and 1000 kg jumbo bags
Liquid	IBCs and bulk / tanker

We quote FOB or CIF to African ports including Durban, Mombasa, Dar es Salaam, Tema/Takoradi, Lagos/Apapa, Beira and Walvis Bay, with per-batch COA and SDS and third-party inspection on request. See export to Africa: packaging, ports and documents for a worked example of the supply package.

Frequently Asked Questions

Is PAC suitable for drinking water in Africa?

Yes – use the drinking-water grade and check its heavy-metal limits and any local approvals. It is widely used for potable supply.

Should I buy PAC as solid or liquid?

Liquid (IBC or tanker) cuts handling and dust but costs more to ship; solid (bags or jumbo bags) is common for export and is dissolved on site. Choose by your dosing setup and freight economics.

What basicity should PAC have?

Typically 40-80%. Higher basicity gives better performance in many waters, but the right value depends on your water – confirm by jar test.

Can you supply PAC to African ports?

Yes, FOB or CIF to Durban, Mombasa, Dar es Salaam, Tema/Takoradi, Lagos/Apapa, Beira, Walvis Bay and others.