The physical–chemical precipitation is simple to implement,
reliable and efficient but presents several disadvantages such as
increased operating costs due to the consumption of chemical
reagents and corrosiveness of some of the coagulants which may
lead to other problems . Besides, excess sludge production
through coagulation, flocculation and precipitation may be lead to
problem in terms of disposal unless the sludge produced is able to
be recycled for other purposes.