Exergy savings and exergy production in municipal wastewater treatment focus on thermodynamical concept and measurement devices.

Abstract: This report represents an overall view on thermodynamical studies of wastewater treatment plant, concepts like exergy, emergy and entropy. In addition, there has been an introduction of calorimetry. A common unit of measurement of organic contents in wastewater treatment facilities is COD. However, the unit of measurement which shows the sustainability of an industry is exergy and emergy. According to the calculations represented in this report it has been tried to make a correlation between the COD and exergy in order to make it easier to assess the sustainability of a treatment plant. The calorific measurement methods which have been used in the food science can also be used in wastewater treatment industry. Therefore, it is possible to replace COD and BOD measurement devices with online calorific measurements. It has been tried to find a correlation between exergy value and calorific contents. Accordingly, if the calorific values in wastewater input and output are known they can be transferred into exergy values. The energy and exergy production from wastewater has been observed in a Microbial Fuel Cell made in the laboratory and the measured values of current produced by the microbial activities has been analyzed in this report. For future studies, exergy can be used directly in modeling a wastewater treatment plant and improving an already made one.