Textile wastewater treatment and electricity generation by Microbial Fuel Cell with freezing technology as pre-treatment (A No-water discharge approach).

Abstract: Textile wastewater contains very high concentration of color, COD, suspended solids and other pollutants. Methods such as reverse osmosis, nano-filtration and ultrafiltration are known to be effective to remove some pollutants but these methods are very expensive. A new treatment approach which is the combination of freezing technology and Microbial Fuel Cell technology has been studied in this thesis work and seems to have great potential to remove color and COD from textile wastewater. Freezing splits a diluted stream into two different streams; one stream in which water is transferred into ice with a low pollutant concentration leaving a concentrated stream with pollutants. Microbial fuel cell uses the concentrated stream to convert biochemical energy into electrical energy. Three different types of substrates, KMnO4 solution, municipal wastewater and orange juice, were studied. Freezing technology can produce high quality water by neutralizing pH-value; close to 7.0, removal of COD is more than 95% and separating color by almost 100%. Similarly MFC can remove color, and COD by 88.8% and 73.6% respectively. The maximum generation of electrical power by MFC was estimated to 1.03 mW/m2 of electrode area. The findings suggest that this new approach of textile wastewater treatment can be a costeffective way to remove pollutants from textile wastewater while generating some electricity.