Study On Biodegradation Of Vat Scarlet R And Blue Salt VB

Wastewater that is emissed from dye manufacturing and textile industry is difficult to be treated, too much water consumption and emission, futhermore, complicated component, high color and strong toxicity. This paper studied the biodegradation of dyes in wastewater: Blue Salt VB's decoloralization and degradation stains VB-12, A-7 were isolated separately; Vat Scarlet R's decoloralization and degradation stains R-4, N-8 were isolated separately. A new decoloralized gene engineering stain H2(based on the strain VB-12 and R-4 ) was created through protoplast fusion technique. A new degradated gene engineering stain J1(based on the strain A-7 and N-8) was created through protoplast fusion technique. The optimum process conditions of strains were determined and the results were showed as follows:1. Blue Salt VB's high effective decoloralization stain VB-12 and Vat Scarlet R's high effective decoloralization stain R-4 were screened based on decoloralization rates, and Blue Salt VB's high effective degradation stain VB-12 and Vat Scarlet R's high effective degradation stain R-4 were screened based on degradation rates of CODCr. after enrichment and isolation. Based on their phenotypic characteristics, physiological and biochemical tests,VB-12, R-4, A-7, N-8 were preliminarily identified as Citrobacter.sp , Pseudmonas.sp, Xanthomonas.sp, Pseudmonas.sp. respectively.2. The four stains'auxotroph mutants were obtained, including V-12 mutated to glycocoll auxotroph QV, A-7 mutated to histidine auxotroph QA, R-4 mutated to arginine auxotroph QR and N-8 mutated to astartate auxotroph QN. The four strains'optimal conditions of protoplast preparation and reproduction were obtained by Orthogonal experiments. Using auxotroph mutants as the marks of protoplast fusion, the excellent fusants H2 and J1 were constructed. H2 can decolorlize Blue Salt VB and Vat Scarlet R, while J1 can degrade products of decolarization. H2 and J1 had stable heredity.3. Optimal treatment conditions were determined by orthogonal experiment in anaerobic-aerobic treatment process. The optimum conditions of high effective stains were as follows: inoculation 5g/L, HRT 46h, influent CODCr 1800mg/L, aeration volume 0.52L/min. Under these conditions, decolorization and degradation rates were above 87%. The optimum conditions of gene engineering stains were as follows: inoculation 5g/L, HRT 38h, influent 1800mg/L, aeration volume 0.52L/min. Under these conditions, decolorization and degradation rates were above 92%. Comparing gene engineering stains with high effective stains, gene engineering stains were multi-functional, adaptable. They highly increased the decolorization and degradation rates.