Is polyaluminium chloride a safe coagulant?

Polyaluminium Chloride is a safer alternative to several other chemical coagulants. For instance, aluminium sulphate has been widely used as coagulant for many years. It removes contaminates and general turbidity from water during the water treatment process.

Do coagulants increase aluminum concentrations in treated water?

1. Introduction Alum and polyaluminum chloride (PACl) coagulants are widely used at water treatment plants to remove turbidity and dissolved substances from water. However, concerns have been raised that the use of such coagulants may increase aluminum concentrations in treated water (Miller et al., 1984; Ohno et al., 2009).

Is polyaluminium chloride better than polyelectrolyte – alum-based coagulation?

At the Barekese Water Treatment Plant in Ghana, an alternative, the polyelectrolyte – polyaluminium chloride (PAC) is also used in coagulation but limited information is available on the operating conditions required to achieve better performance than alum-based coagulation.

What is the difference between Alum and polyaluminium coagulants?

For water treatment applications, instead of Alum, now there are several alternative aluminium-based coagulants. Polyaluminium coagulants (PACl) consume considerably less alkalinity than Alum. Compared to Alum, PACl works effectively over a broader pH range (5.0 to 8.0).

What pH should aluminum sulfate be used for coagulation?

The optimal pH range of aluminum sulfate is between 5 and 7.5, which means the coagulant performs at its best in slightly acidic or neutral solutions. Ferric chloride may be a better option for coagulation below this level of pH, while ferrous sulfate may be suitable for the treatment of more alkaline water.

Can aluminum sulfate be used for water coagulation?

Sold in blocks and easily stored, aluminum sulfate has proved a viable option for water coagulation and treatment in third-world countries, as well as in the United States. The optimal pH range of aluminum sulfate is between 5 and 7.5, which means the coagulant performs at its best in slightly acidic or neutral solutions.