Emergy Analysis of Wastewater Treatment Technology

The article presents a brief description and criticism of the current state of the emergy analysis for wastewater treatment plants (WWTP) and a new index for the assessment of environmental facilities. As well as in the analysis of economic systems, the assessment of systems and plants for the protection of the environment, provided in the literature, is based on the calculation of basic emergy indices (the emergy yield ratio (EYR) isthe ratio of the sum of renewable kinds of emergy, non-renewable ones and purchased or free resources to the emergy of purchased resources; the environmental loading ratio (ELR) is defined as the ratio of the sum of nonrenewable and imported (purchased) emergy to renewable emergy; the emergy sustainability index (ESI) equal to the ratio of economy (EYR) to depletion (ELR) determines the degree of viability of the facility), which does not take into consideration a fundamental difference of production facilities and facilities designed to protect the environment from pollution. The environmental performance of the facilities, calculated as the ratio of the difference between the emergy estimates of preventable damage and caused damage to the preventable damage, must serve as the main emergy index for the assessment of treatment facilities.