Is polyaluminum ferric chloride an inorganic coagulant?

1. Introduction Polyaluminum ferric chloride (PAFC) is an efficient inorganic polymeric coagulant [1], [2]. Many studies [3], [4], [5] have demonstrated that inorganic polymeric coagulants were more effective than conventional inorganic coagulating salts in coagulation due to their resistances to the influence of wastewater initial pH.

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 turbidity of a PAC flocculated water?

The average PAC dose, since its introduction in December 2016, was 33.2 mg/l, with minimum and maximum dosages of 14.1 and 43.8 mg/l. Since PAC's introduction, the turbidity of the flocculated water has remained fairly stable, within the range 3.5 to 6.1 NTU. When alum was in use, the range was 2.0 to 6.4 NTU (Figure 4).

What is the optimal pH range for Pac coagulation?

The optimal pH range for PAC coagulation performance was 7.5 to 8.0. The coagulation process in conventional water treatment could be enhanced and the ensuing water pH decline reduced appreciably by applying the right dosage of polyaluminium chloride and appropriate process conditions of pH, fluid mixing speed matrix and residence time.

Do surface characteristics of PAFC and flocs affect coagulation mechanisms?

However, there was lack of systematic research on the surface characteristics of PAFC and the flocs generated in water treating process and their effect on the coagulation mechanisms.

How is PAFC synthesized?

PAFC was synthesized following two steps: First, 50 g of blast furnace dust was placed in a 500 mL three-necked round bottom flask equipped with stirrer and reflux device. Then, 2 g NaF, 150 mL of HCl diluted solution (36%, freshly diluted 1:1 with ultrapure water) and 5 mL of HNO 3 were added.