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.

Is polyaluminium chloride better than alum?

Application of polyaluminium chloride under the recommended process conditions produces relatively better quality treated water than alum application. Freshwater is finite and required for human and ecosystem survival.

Does PAC inhibit filamentous bulking of activated sludge?

Results showed that PAC addition significantly decreases the relative abundance of filamentous bacteria, indicating its potential in inhibiting the filamentous bulking of activated sludge. Thus, the much higher SVI (Sludge Volume Index) in SBR3 than other SBRs had little to do with filamentous bulking, but mainly due to the charge reversal of the sludge flocs.

Why are aluminium based polymers used in water treatment?

These shortfalls in the use of alum have led to the synthesis of improved, aluminium-based polymers, which have been used extensively, over the few last decades, for treating water due to their high efficiency at lower dosages, and wider pH and temperature application ranges (Sahu & Chaudhari 2013).