Biodegradation of Black Liquor

Bacterial strains and yeast strains were screened for treatment of black liquor. 17 bacterial cultures of genus - arthrobacter, cellulomonas, chainia, pseudomonas and glucanobacter were used. 19 yeast cultures having genuskluyveromyces, pachysolen, pichia, rhodotorula, saccharomyces, candida and yerrowia were used for study. At pH 8.0, 58.33% sugar utilization, 16.14% phenol degradation, 37.81% decolorization was obtained by using Candida catanula NCIM 3337, C. brumptii 3402, Pseudomonas fluorescens 2653 respectively. 45.63% sugar utilization, 29.48% phenol degradation , 20.97% decolorization was observed by using Yerrowia lipolytica NCIM 3472, Pseudomonas fluorescens 2173, Yerrowia lipolytica 3589 respectively at pH 6.5. 63.49% sugar utilization was observed by Pseudomonas fluorescens 2141 at pH 4.5. 28.85% phenol degradation was done by Pachysolen tannophilus 3445 at pH 4.5. 63.26% decolorization was observed for Candida lambica 3532 at pH 4.5. Use of biomass for decolorization was attempted in this study. Fermentation of fruits was carried out. Sapota, fig, papaya, pineapple, banana, guava and tamarind were used for fermentation. Fermentation was done by using baker's yeast. Residue from ethanol fermentation was used for decolorization of black liquor. Decolorization was obtained by residue from banana and tamarind fermentation residue was higher. It was 63.79 and 65.62% decolorization for banana and tamarind fermentation residue respectively.