Journal of Water and Climate Change (Aug 2021)
Conventional and zero liquid discharge treatment plants for textile wastewater through the lens of carbon footprint analysis
Abstract
Effluent treatment plants act as the last line of defense against the discharge of pollutants from industrial effluents. The higher resource consumption, variety of dyes, and auxiliary chemicals used for textile manufacturing classify it as a highly polluting industry. Standards for color, organics, and dissolved solids are becoming more stringent with time, and local regulators are forced to insist on the establishment of zero liquid discharge (ZLD) units. However, the application of the ZLD concept has the major limitation of high energy consumption when compared with the conventional wastewater treatment plant. The application of carbon footprint analysis to both units would provide a comprehensive solution to the carbon footprint computation and bring out the advantages of the ZLD. The carbon footprint of a typical ZLD treatment facility in south India was found to be 10,598 tons of carbon dioxide equivalent per year (tCO2eq/year), which is only one-third more than that of a conventional treatment plant. The carbon footprint of a given ZLD treatment facility can effectively be used as a performance indicator to limit the overall energy consumption. HIGHLIGHTS Comparative evaluation of the carbon footprint between conventional and zero liquid discharge (ZLD) treatment plants for textile wastewater is the first of its kind.; Comprehensive carbon emission quantification by the inclusion of carbon footprint due to the discharge of treated effluent into water bodies/land and ground water extraction within the system boundaries.; Carbon footprint of the ZLD treatment plant was found to be nearly 35% higher than the carbon footprint of the conventional treatment plant with a capacity of 4.4 million liters per day.; The application of carbon footprint analysis is a novel performance analysis tool for comparing the different industrial wastewater treatment plants including the ZLD system.;
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