| Dissertation note |
Textile sector is one of the large exporting and the most important industrial sector of Pakistan. It accounts about 64% of the total export from our country. At present there are 650 textile processing units working in Pakistan. Textile industries consume large amount of water for wet processing of textile. Out of many contaminants present in wastewater, such as acids, bases, toxic organic and inorganic dissolved solids, and colors, Colors are considered the most undesirable and are mainly caused by dyes which are used in textile dying industry. The objective of the study was to decolorize the cotton industry waste water effluents by treatment with microorganisms like Trichoderma harzianum and Aspergillus flavus, an extent to make it least harmful to water habitats and also to make it fit for irrigation purposes. The influencing parameters that affect the percentage of decolorization rates are optimized in still culture fermentation. Spectrophotometric analysis method was used to estimate decolorization of textile industry effluent at its ?max (350nm). The optimal values of the parameters such as effluent to water ratio, fermentation time, pH, and carbon to nitrogen ratio are found to be 1:0, 72 hours, 4.0, and 1: 2.33 for Trichoderma harzianum and 1:1, 72 hours, 5.0, and 1: 2.33 for Aspergillus flavus respectively. The concentration of different ions like Ca+2, Mg+2 and H2PO4-1 were also optimized for maximum decolorization and the optimized conc. were 0.025%, 0.025% and 0.025% for Trichoderma harzianum and 0.05%, 0.1% and 0.05% for Aspergillus flavus respectively. The maximum percentage of decolorization at the optimized conditions on large scale was found to be 83.31% and 80.02 % with Trichoderma harzianum and Aspergillus flavus respectively.
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