ABSTRACT
When the ef€uent from secondary treatment does not meet regulatory requirements for discharge, additional treatment may be needed to reduce the levels of speci‹c contaminants. This is usually termed as advanced treatment or tertiary treatment. Advanced treatment processes are used for removal of nutrients such as nitrogen and phosphorus, removal of residual total suspended solids, removal of speci‹c heavy metals or inorganics, and removal of emerging contaminants of concern, among others. Advanced treatment processes may be incorporated within the primary or secondary treatment units, e.g. for biological nutrient removal, or they may be added separately following secondary treatment, e.g. for wastewater reclamation. These include chemical precipitation, carbon adsorption, granular media ‹ltration, and membrane ‹ltration, among others. A number of these processes will be discussed in detail in this chapter with regard to the types of contaminants that are removed by the processes. The focus of this chapter will be the removal of nitrogen, phosphorus, suspended and dissolved solids, and other inorganics from wastewater.
