Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kin...Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics pa-rameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the mod-erate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (KS) were 0.0208-0.0642 L/(gMLSS)h and 0.44-0.59 (gCOD)/L respectively at 20 C-35 C. Activation energy (Ea) was 6.05104 J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment.展开更多
Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan p...Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan particles （FCCP）, was examined. The effects ofpH, stirring time, sedimentation time and temperature on color, COD, turbidity and NH3-N removal were determined. The optimum dosage of FCCP and the influence of individual factors on removal efficiency were tested. The optimum parameters determined using the L16 （45） orthogonal experiment were as follows： FCCP （weight ratio of chitosan to fly-ash 1：6） dosage, 4 g.L^-1; temperature, 35℃; pH, 4. The stirring time and sedimentation time were 20 min and 5 h, respectively. Under these optimum conditions, the color, COD and NH3-N removal ratios were 97%, 80% and 75%, respectively.展开更多
Since the azo dyes widely used in textile-dyeing industry are toxic, highly persistent, and ubiquitously distributed in the environment, their treatment efficiencies and fade in ecosystems have received worldwide atte...Since the azo dyes widely used in textile-dyeing industry are toxic, highly persistent, and ubiquitously distributed in the environment, their treatment efficiencies and fade in ecosystems have received worldwide attention. Due to the microbes play important roles in azo-dye degradation, exogenous nutrient addition is used as a promising biostimulation strategy to improve the treatment efficiencies of azo-dye wastewater. However, little is known about the effects of different kinds of exogenous nutrients on the azo-dye wastewater treatment directly. Here, three kinds of common nutrients, glucose, starch and yeast extract, were added to the sequencing batch reactors （SBR） for the treatment of wastewater containing acid red 73 to compare the biostimulation efficiencies by investigating the dye＇s removal efficiencies and the changes of related water qualities. Our results showed that the reactors added yeast extract had highest removal efficiencies and chemical oxygen demand （COD） as well, followed by glucose and starch. The removal rates of acid red 73 and COD were 90.63% and 8713% in the reactors added yeast extract, respectively, while 86.49% and 78.4% in those with glucose and 85.38% and 75.2% in those with starch. This study provided some useful information for the biostimulation strategy of azo-dye wastewater treatment and preliminarily suggested that yeast extract would be the optimal choice.展开更多
文摘Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics pa-rameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the mod-erate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (KS) were 0.0208-0.0642 L/(gMLSS)h and 0.44-0.59 (gCOD)/L respectively at 20 C-35 C. Activation energy (Ea) was 6.05104 J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment.
基金Supported by the Science and Technology Development Foundation of Foshan (No.2005060071)
文摘Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan particles （FCCP）, was examined. The effects ofpH, stirring time, sedimentation time and temperature on color, COD, turbidity and NH3-N removal were determined. The optimum dosage of FCCP and the influence of individual factors on removal efficiency were tested. The optimum parameters determined using the L16 （45） orthogonal experiment were as follows： FCCP （weight ratio of chitosan to fly-ash 1：6） dosage, 4 g.L^-1; temperature, 35℃; pH, 4. The stirring time and sedimentation time were 20 min and 5 h, respectively. Under these optimum conditions, the color, COD and NH3-N removal ratios were 97%, 80% and 75%, respectively.
基金supported by the National Natural Science Foundation of China(51308133)Guangdong Provincial National Natural Science Foundation(2014A030308019)+1 种基金Science and Technology Planning Project of Guangdong Province(2015A020215016)the support of Guangdong Institute of Microbiology
文摘Since the azo dyes widely used in textile-dyeing industry are toxic, highly persistent, and ubiquitously distributed in the environment, their treatment efficiencies and fade in ecosystems have received worldwide attention. Due to the microbes play important roles in azo-dye degradation, exogenous nutrient addition is used as a promising biostimulation strategy to improve the treatment efficiencies of azo-dye wastewater. However, little is known about the effects of different kinds of exogenous nutrients on the azo-dye wastewater treatment directly. Here, three kinds of common nutrients, glucose, starch and yeast extract, were added to the sequencing batch reactors （SBR） for the treatment of wastewater containing acid red 73 to compare the biostimulation efficiencies by investigating the dye＇s removal efficiencies and the changes of related water qualities. Our results showed that the reactors added yeast extract had highest removal efficiencies and chemical oxygen demand （COD） as well, followed by glucose and starch. The removal rates of acid red 73 and COD were 90.63% and 8713% in the reactors added yeast extract, respectively, while 86.49% and 78.4% in those with glucose and 85.38% and 75.2% in those with starch. This study provided some useful information for the biostimulation strategy of azo-dye wastewater treatment and preliminarily suggested that yeast extract would be the optimal choice.
