Municipal Wastewater Treatment

This chapter begins with a description of the nature of wastewater commonly known as sewage. Subsequently, modern wastewater treatment is discussed including primary, secondary and tertiary treatment, and the removal of microbial pathogens by sewage treatment processes. Particular emphasis is placed on secondary treatment including trickling filters and conventional activated sludge as well as new technologies such as the Bardenpho process. Treatment via oxidation ponds and septic tanks is also described. Subsequently, land application of wastewater is discussed, including wetlands and aquaculture systems. Also presented are technologies for sludge processing to produce Class B biosolids including stabilization technologies such as aerobic and anaerobic digestion. Finally, technologies to produce Class A biosolids are described including composting, lime and heat treatment.