Why is polyaluminum chloride a good coagulant for water treatment?

Polyaluminum chloride (PAC) is highly effective coagulant for water treatment over conventional coagulants because of low dosage requirement, shorter flocculation time, smaller amount of sludge, high efficiency and low aluminum residual in treated water .

Do polyaluminum chloride coagulant characteristics affect dissolved residual aluminum concentrations?

In this study, the effect of polyaluminum chloride (PACl) coagulant characteristics on dissolved residual aluminum concentrations after coagulation and filtration was investigated. The dissolved residual aluminum concentrations at a given coagulation pH differed among the PACls tested.

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.

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).

Which coagulation pH is a key to reducing residual aluminum concentration?

In their other data (Yan et al., 2007), 83%- and 73%-basicity PACls shows lower residual aluminum concentration than 53%-basicity PACl even though the coagulation pH values were slightly higher alkaline pH. Therefore, basicity >70% was suggested as a key for reducing residual aluminum concentration.

What is high-purity poly-aluminum chloride (PACL)?

Poly-aluminum chloride (PACl) is one of the common coagulants for water and wastewater treatment. A new Chinese national standard of PACl has been implemented, where the concentration of insoluble substances, iron and heavy metals is to be controlled strictly, then researches on the preparation of high–purity PACl are needed.