Energy-Wastewater Treatment and Solids Disposal

Recently there has been an increase in the use and promotion of so-called advanced wastewater treatment and solids handling methods to meet discharge standards. The total energy consumption, by any wastewater treatment or disposal process, is proposed as an index for measuring the impact on the total environment. Two specific comparisons, based on the experiences of the City of Los Angeles, are presented: (1) Biological versus Chemicophysical process for wastewater treatment: and (2) ocean versus land disposal for wastewater solids. The chemicophysical processes required five times more energy then the biological process; and land disposal of solids required 16 - 35 times more energy than ocean disposal. This indicates that in some cases so-called advanced wastewater treatment processes as well as land disposal of wastewater sludges may not necessarily result in the least overall environmental impact (degradation).