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.

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 .

Does high-purity PACL reduce operating cost?

On the other hand, when the dose was greater than 4 mg L −1 as Al, the high-purity PACl showed great UV 254 -absorbance removal capacity; which was even much greater at high does (e.g., 10 mg L −1). Relative low dose requirement of high-purity PACl indicates the potential of the reduction of operating cost.

What is the basicity of high-purity PACL?

The basicity of high-purity PACl can be maintained at about 92% after the adjustment by calcium aluminate (Table 3), it has exceeded the national and international standards of PACl.

Is Pac better than aluminum sulfate & aluminum chloride for removing turbidity & nom?

Moreover, the performance of synthesized PAC was also very much higher as compared with aluminum sulfate and aluminum chloride for removing turbidity and NOM from synthetic water samples. The coagulant dose and the lime required of synthesized PAC were reduced more than two folds relative to aluminum sulfate and aluminum chloride doses.

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.