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 .

Are pre-polymerized aluminum salts a good coagulant for water treatment?

Although the pre-polymerized aluminum salts (PACl) show better coagulation performance in some cases in comparison with conventional coagulants , their applications in water treatment are still limited due to the high cost of raw materials . Therefore, it is urgently required to develop more cost-effective coagulants for water treatment.

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.

What is the coagulation time for aluminum sulfate and aluminum chloride coagulants?

However, for aluminum sulfate and aluminum chloride coagulants the coagulation time and settling time were reached to 15 and 35 min, respectively. The results revealed that the residual aluminum concentration in the treated water was very small for synthesized PAC coagulant which was <0.2 mg L −1.

Do polyelectrolyte composite coagulants improve coagulation performance?

El Foulani, Mohamed. Tahiri & Polyaluminum chloride (PAC)/natural polyelectrolyte composite coagulants have received considerable attention recently due to their exceptional properties in drinking water treatment. However, the criteria for selecting polyelectrolytes grafted into the PAC to improve coagulation performance are not yet well defined.

Which coagulants are used for water treatment?

Aluminum sulfate, ferric chloride, ferric sulfate and polyaluminum chloride are inorganic based chemicals which can be used for water treatment . Aluminum based coagulants have higher color and turbidity removal efficiencies, in comparison with ferric based coagulants .