How is polyaluminium chloride dosed?

This was dramatically improved, to over 90%, by dosing polyaluminium chloride. PAC is directly and continuously dosed from the containers in which it is delivered at a rate of about 0.1ml/m 3 of the circulation flow. (It is very important that it is not diluted with water as it will form a gel.)

What is polyaluminium chloride?

Polyaluminium chloride (PAC) is a pre-hydrolyzed inorganic polymeric coagulant that is being used widely in the treatment of water supply and wastewater by forming a hard and heavy Al (OH)3* precipitate, in addition to having a smaller effect on pH.

What is the coagulation removal rate of polyaluminium chloride (PAC)?

Without coagulation removal rates in a single pass of a medium-rate filter were about 50%. This was dramatically improved, to over 90%, by dosing polyaluminium chloride. PAC is directly and continuously dosed from the containers in which it is delivered at a rate of about 0.1ml/m 3 of the circulation flow.

How should Pac be dosed in a peristaltic pump?

PAC should be dosed continuously using a peristaltic pump. All grades of PAC should be dosed at a rate of 0.1ml/m 3 of the total flow rate. PWTAG Technical Note released in February 2014 about polyaluminium chloride (PAC) dosing. Continuous coagulation with PAC is recommended by PWTAG.

What is a normal dosing rate for pwtag PAC?

PWTAG recommends a normal dosing rate of 0.1ml/m 3 of the total flow rate, which it has also described as 0.005ml/m 3 as aluminium. There are now a number of different grades of PAC with aluminium concentrations between 9.5% and 18%. The concentration of aluminium is not the only consideration when selecting a grade of PAC to use.

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.