What is chemical coagulation

Chemical coagulation has been in practice for several decades to precipitate the soluble heavy metals present in the waste water, as hydroxides and facilitate their removal by physical separation through sedimentation process. Ferrous sulphate, hydrated lime, alum, etc. are the most common chemical coagulants being used in Industries. 

The inherent disadvantage of this process is the generation of large quantities of chemical sludge and its classification as hazardous waste, necessitating the need for seemed landfilling of hazardous solid wastes. 

Due to unavailability of suitable open area, the dumping of sludge is creating a problem. 

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