The biological aerated filter （BAF） was used to treat the oil-field produced water. The removal efficiency for oil, COD, BOD and suspended solids （SS） was 76.3%-80.3%, 31.6%-57.9%, 8.6.3%-96.3% and76.4%--82.7%, re...The biological aerated filter （BAF） was used to treat the oil-field produced water. The removal efficiency for oil, COD, BOD and suspended solids （SS） was 76.3%-80.3%, 31.6%-57.9%, 8.6.3%-96.3% and76.4%--82.7%, respectively when the hydraulic loading rates varied from 016m·h^-1 to 1.4m·h^-1. The greatest partof removal, for example more than 80% of COD removal, occurred on the top 100cm of the media in BAF. The kinetic .performance of BAF indicated that the relationship of BOD removal efficiency with the hydraulic loadingrates, in biological aerated filters could be described by c1/c1=l-exp（-2.44/L^0.59）. This equation could be used topredict the B OD.removal efficiency at different hydraulic loading rates.展开更多
Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension...Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension and oil-field produced water. The bacterial strain was identified as Klebsiella sp. MYC according to its morphological and biochemical characteristics and 16SrDNA sequence. The optimal medium for bioflocculant production by this bacterial strain was composed of cane sugar 20 g L^-1, KH2PO4 2 g L^-1, K2HPO4 5 g L^- 1, （ NH4）2SO4 0.2 g L^-1, urea 0.5 g L^- 1 and yeast extract 0.5 g L^- 1, the initial pH being 5.5. When the suspension of kaolin clay was treated with0.5% of Klebsiella sp. MYC culture broth, the flocculating rate reached more than 90.0% in the presence of 500mg L^-1 CaCI2, while the flocculating rate for oil-field produced water was near 80.0% in a pH range of 7.0 - 9.0 with the separation of oil and suspended particles from the oil-field produced water under similar conditions. The environment-friendly nature of the bioflocculant and high flocculating rate of the strain make the bioflocculant produced by Klebsiella sp. MYC an attractive bioflocculant in oil-field produced water treatment.展开更多
In this paper, fouling mechanisms of mullite ceramic membranes for treatment of oily wastewaters in hybrid coagulation-microfiltration （MF） process presented. Hermia＇s models for cross flow filtration were used to ...In this paper, fouling mechanisms of mullite ceramic membranes for treatment of oily wastewaters in hybrid coagulation-microfiltration （MF） process presented. Hermia＇s models for cross flow filtration were used to investigate the fouling mechanisms of membranes with various coagulating chemicals concentrations. Four coagu lating chemicals （FeC12.4H20, FeSO4.7H20, A1C13-6H20 and A12（SO4）3.18H20） plus Ca（OH）2 of the same concen- tration were evaluated in the coagulation-MF hybrid process with different concentrations （0, 50 mg.L-1, 100 mg.L-1 and 200 mg.L-1）. To determine whether the data agree with models under consideration, the coefficients of determination （R2） of all models were compared with one another. In addition, average prediction errors of models were calculated. The results showed that cake filtration model can be applied for prediction of permeation flux decline for MF and coagulation-（MF） hybrid process with the best average error equal to 0.09%. Results indicated that pore blocking behavior changes as time of filtration increases, and one model cannot predict pore blocking behavior in all filtration time with very good precision.展开更多
Wastewater containing high concentrations of phenol and sodium sulfate is generated in sebacic acid （SA） industry. Castor oil acid, a raw material for producing SA, can be used to extract phenol from wastewater in o...Wastewater containing high concentrations of phenol and sodium sulfate is generated in sebacic acid （SA） industry. Castor oil acid, a raw material for producing SA, can be used to extract phenol from wastewater in order to reduce the amount of phenol used in the process and discharge of phenol. The results show that the extrac- tion mechanism is that hydroxyl group of phenol is linked to carboxyl group of castor oil acid by hydrogen bond. The extraction process approaches equilibrium in 30 min. Extraction ratio increases with the increase of sodium sulfate and castor oil acid, and decreases as phenol increases. When the oil-water ratio is 1 ： 3, the optimal distribu- tion coefficient of 40 is obtained. Phenol saturation concentration in castor oil acid is 1.03 mol.L-1 after extraction for 4 times. The equilibrium constant （Kex） at 25℃ is 8.41 and the endothermic enthalpy （AH） is 1.513 kJ.mo1-1. The Gibbs free energy （AG） is -5.277 kJ. tool-1 and the value of AS is calculated to be 22.3 J. mo1-1. K-1.展开更多
Bioflocculants have received increasing attention in research because they are low cost,non-toxic,biodegradable,operationally simple and useful in many water and wastewater treatment applications.In this study,we focu...Bioflocculants have received increasing attention in research because they are low cost,non-toxic,biodegradable,operationally simple and useful in many water and wastewater treatment applications.In this study,we focused mainly on the screening of the flocculant-producing strain and its application in oily wastewater treatment.Bacteria strain B-6-1 was isolated by the pyridine screening method.UPC-1 reagent produced by B-6-1 had efficient flocculating activity.It was deduced that the main component of UPC-1 reagent was polysaccharide through purification and analysis.The influence of dosage of reagent,pH value,temperature and oil concentration on the flocculation effect of UPC-1 reagent was investigated.展开更多
Pulse electro-coagulation flotation was used to treat oil wastewater of high oil content.Different operational conditions were examined,including current density,reactive time,electrode distance,pH and pole switching ...Pulse electro-coagulation flotation was used to treat oil wastewater of high oil content.Different operational conditions were examined,including current density,reactive time,electrode distance,pH and pole switching time.Orthogonal tests were carried out to identify the optimal operational conditions for this technique.Considering the treatment cost and efficiency together,the optimal operational conditions were an electrode distance of 3.3 cm,pH of 4,current density of 49.38 mA/cm2,reaction time of 15 min and pole switching time of 10 s.The removal efficiency of oil wastewater under normal conditions reached up to 96.21%.The influences of different factors on removal efficiency were in the following decreasing sequence:pH> current density > pole switching time > reactive time > board distance.展开更多
The petroleum acids in crude oil were separated by extraction with column chromatogram and anion exchange resin. The separation effect and the related composition and structure of petroleum acids were obtained by usin...The petroleum acids in crude oil were separated by extraction with column chromatogram and anion exchange resin. The separation effect and the related composition and structure of petroleum acids were obtained by using IR (Infra-Red) spectra techniques. The separated petroleum acids can under special conditions react with methanol to form corresponding esters, which can be analyzed by CI (chemical ionization)-MS (mass spectrometry). The characteristic ion peaks m/z (M+15)+ of naphthenic acid esters combined with z-series formula CnH2n+zO2 of naphthenic acids can be used to classify naphthenic acids into fatty acids, mono-cyclic, bi-cyclic, tri-cyclic, and higher polycyclic acids. The analytical results can give the molecular weight and the carbon number distribution of petroleum acids contained in crude oil. The results of study indicate that this method is simple, rapid and easy in operation.展开更多
The concept of SBCR was put forward to treat sauce wastewater. Further study showed that adding appropriate amount of calcium chloride to SBR can improve the quality of effluent. The removal rate of COD and color was ...The concept of SBCR was put forward to treat sauce wastewater. Further study showed that adding appropriate amount of calcium chloride to SBR can improve the quality of effluent. The removal rate of COD and color was 84% and 80%, 36%, 96% higher than those of traditional SBR respectively. The results of continuous experiments and biophase observing showed that calcium chloride accumulation increased the sludge production slightly while the sludge dewatering characteristic was improved.展开更多
Experimental design was applied in the optimization of crude oil adsorption from saline waste water using raw bagasse.The application of response surface methodology(RSM) was presented with temperature,salinity of wat...Experimental design was applied in the optimization of crude oil adsorption from saline waste water using raw bagasse.The application of response surface methodology(RSM) was presented with temperature,salinity of water,pH,adsorbent dose,and initial oil content as factors.A quadratic model could be used to approximate the mathematical relationship of crude oil removal on the five significant independent variables.Predicted values and experimental values are found to be in good agreement with R2 of 97.44%.The result of optimization shows that the maximum crude oil removal is equal to 67.38% under the optimal condition of temperature of 46.53 °C,salinity of 37.2 g/L,pH of 3,adsorbent dose of 9 g/L and initial oil content of 300×10-6.展开更多
After conducting a lot of screening experiments the appropriate flocculating formulations for treating high-concentration wastewater discharged from a certain refinery were selected. The oil removal rate and COD remov...After conducting a lot of screening experiments the appropriate flocculating formulations for treating high-concentration wastewater discharged from a certain refinery were selected. The oil removal rate and COD removal achieved by these flocculating formulations were better than that achieved by the conventional compound formulation consisting of polyaluminium chloride(PAC) and polyacrylamide(PAA) . Addition of an oil/water separating agent to the formulation could improve its oil removal performance to facilitate the oil/water separation of the oil-in-water emulsion in the high-concentration wastewater along with improved adaptability of the formulation to the wastewater containing high concentration of pollutants. This flocculating agent has promising prospects for commercial application.展开更多
The aim of this work is to assess the short term effect of OMWW （olive mill waste water） application on chemical and biological soil properties. A field experiment was carried out in southern Tunisia. OMWW applicati...The aim of this work is to assess the short term effect of OMWW （olive mill waste water） application on chemical and biological soil properties. A field experiment was carried out in southern Tunisia. OMWW application was done at rates equivalent to 0, 15, 30 and 45 m^3/ha. Results showed that increasing rates of OMWW enhance the soil fertility due to its richness in organic matter such as N and P. A rapid increase of microbial biomass （during 14 days of incubation） of OMWW amended soils occurred. However, a high increase in salinity values and phenolic compounds concentrations was observed during this experiment.展开更多
An economical and environmental sustainability of bioplastic production is dependent on the use of low cost and waste C-sources as raw materials. OMW （Olive Mill Wastewater） with its high organic load represents a d...An economical and environmental sustainability of bioplastic production is dependent on the use of low cost and waste C-sources as raw materials. OMW （Olive Mill Wastewater） with its high organic load represents a dangerous polluting waste. Herein the authors present an integrated process for the simultaneous recovery of polyphenols, high value natural antioxidants, production of PHAs （polyhydroxyalkanotes）, thermoplastic bio-polymers, in particular of PHB （poly-3-hydroxybutyrate） starting from OMW. The combination of membrane filtration and bacterial digestion of OMW resulted in very high yields of polyphenols （3 2.5 g/L） and PHB （31.4 mg/L.h） if compared with the state of the art. These results make the technical approach described here effective for reducing the polluting effect of OMW and maximizing the valuable product yield. Moreover the process is readily suitable for an industrial scale PHB production from OMW.展开更多
The aim of the present study was to implant an efficient strategy for controlling the level of the effluent-oily foam interface in a DAF （dissolved air flotation） chamber of a pilot-scale prototype. DAF has been suc...The aim of the present study was to implant an efficient strategy for controlling the level of the effluent-oily foam interface in a DAF （dissolved air flotation） chamber of a pilot-scale prototype. DAF has been successfully used in the treatment of oily water, which is one of the main environmental problems in different industrial facilities. Along with important operational parameters, such as microbubble size and flow rate, the control strategy for the automation of a DAF chamber may be an important tool for increasing efficiency. Controlling the level was the strategy chosen to enhance the separation efficiency in a pilot-scale DAF prototype, with monitoring performed using a computational program in LabVIEW （laboratory virtual instrument engineering workbench）. The findings demonstrate that it is possible to maintain the level of the fluid at a reference value established by the operator using the software program through the application of classic proportional integral derivative controllers. Using this control tool, the efficiency of water-oil separation in the pilot flotation chamber prototype was increased to nearly 98%.展开更多
基金Supported by the National Natural Science Foundation of China （No.59978020）.
文摘The biological aerated filter （BAF） was used to treat the oil-field produced water. The removal efficiency for oil, COD, BOD and suspended solids （SS） was 76.3%-80.3%, 31.6%-57.9%, 8.6.3%-96.3% and76.4%--82.7%, respectively when the hydraulic loading rates varied from 016m·h^-1 to 1.4m·h^-1. The greatest partof removal, for example more than 80% of COD removal, occurred on the top 100cm of the media in BAF. The kinetic .performance of BAF indicated that the relationship of BOD removal efficiency with the hydraulic loadingrates, in biological aerated filters could be described by c1/c1=l-exp（-2.44/L^0.59）. This equation could be used topredict the B OD.removal efficiency at different hydraulic loading rates.
文摘Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension and oil-field produced water. The bacterial strain was identified as Klebsiella sp. MYC according to its morphological and biochemical characteristics and 16SrDNA sequence. The optimal medium for bioflocculant production by this bacterial strain was composed of cane sugar 20 g L^-1, KH2PO4 2 g L^-1, K2HPO4 5 g L^- 1, （ NH4）2SO4 0.2 g L^-1, urea 0.5 g L^- 1 and yeast extract 0.5 g L^- 1, the initial pH being 5.5. When the suspension of kaolin clay was treated with0.5% of Klebsiella sp. MYC culture broth, the flocculating rate reached more than 90.0% in the presence of 500mg L^-1 CaCI2, while the flocculating rate for oil-field produced water was near 80.0% in a pH range of 7.0 - 9.0 with the separation of oil and suspended particles from the oil-field produced water under similar conditions. The environment-friendly nature of the bioflocculant and high flocculating rate of the strain make the bioflocculant produced by Klebsiella sp. MYC an attractive bioflocculant in oil-field produced water treatment.
文摘In this paper, fouling mechanisms of mullite ceramic membranes for treatment of oily wastewaters in hybrid coagulation-microfiltration （MF） process presented. Hermia＇s models for cross flow filtration were used to investigate the fouling mechanisms of membranes with various coagulating chemicals concentrations. Four coagu lating chemicals （FeC12.4H20, FeSO4.7H20, A1C13-6H20 and A12（SO4）3.18H20） plus Ca（OH）2 of the same concen- tration were evaluated in the coagulation-MF hybrid process with different concentrations （0, 50 mg.L-1, 100 mg.L-1 and 200 mg.L-1）. To determine whether the data agree with models under consideration, the coefficients of determination （R2） of all models were compared with one another. In addition, average prediction errors of models were calculated. The results showed that cake filtration model can be applied for prediction of permeation flux decline for MF and coagulation-（MF） hybrid process with the best average error equal to 0.09%. Results indicated that pore blocking behavior changes as time of filtration increases, and one model cannot predict pore blocking behavior in all filtration time with very good precision.
基金Supported by the National Natural Science Foundation of China （21006057） and the National Science Foundation for Post-doctoral Scientists of China （20100470351）.
文摘Wastewater containing high concentrations of phenol and sodium sulfate is generated in sebacic acid （SA） industry. Castor oil acid, a raw material for producing SA, can be used to extract phenol from wastewater in order to reduce the amount of phenol used in the process and discharge of phenol. The results show that the extrac- tion mechanism is that hydroxyl group of phenol is linked to carboxyl group of castor oil acid by hydrogen bond. The extraction process approaches equilibrium in 30 min. Extraction ratio increases with the increase of sodium sulfate and castor oil acid, and decreases as phenol increases. When the oil-water ratio is 1 ： 3, the optimal distribu- tion coefficient of 40 is obtained. Phenol saturation concentration in castor oil acid is 1.03 mol.L-1 after extraction for 4 times. The equilibrium constant （Kex） at 25℃ is 8.41 and the endothermic enthalpy （AH） is 1.513 kJ.mo1-1. The Gibbs free energy （AG） is -5.277 kJ. tool-1 and the value of AS is calculated to be 22.3 J. mo1-1. K-1.
基金Funded by the scientific research and technological development project of China national petroleum corporation(No. 2006A50302)
文摘Bioflocculants have received increasing attention in research because they are low cost,non-toxic,biodegradable,operationally simple and useful in many water and wastewater treatment applications.In this study,we focused mainly on the screening of the flocculant-producing strain and its application in oily wastewater treatment.Bacteria strain B-6-1 was isolated by the pyridine screening method.UPC-1 reagent produced by B-6-1 had efficient flocculating activity.It was deduced that the main component of UPC-1 reagent was polysaccharide through purification and analysis.The influence of dosage of reagent,pH value,temperature and oil concentration on the flocculation effect of UPC-1 reagent was investigated.
基金Funded by the Natural Science Foundation of Chongqing(No.2006BB6183)
文摘Pulse electro-coagulation flotation was used to treat oil wastewater of high oil content.Different operational conditions were examined,including current density,reactive time,electrode distance,pH and pole switching time.Orthogonal tests were carried out to identify the optimal operational conditions for this technique.Considering the treatment cost and efficiency together,the optimal operational conditions were an electrode distance of 3.3 cm,pH of 4,current density of 49.38 mA/cm2,reaction time of 15 min and pole switching time of 10 s.The removal efficiency of oil wastewater under normal conditions reached up to 96.21%.The influences of different factors on removal efficiency were in the following decreasing sequence:pH> current density > pole switching time > reactive time > board distance.
文摘The petroleum acids in crude oil were separated by extraction with column chromatogram and anion exchange resin. The separation effect and the related composition and structure of petroleum acids were obtained by using IR (Infra-Red) spectra techniques. The separated petroleum acids can under special conditions react with methanol to form corresponding esters, which can be analyzed by CI (chemical ionization)-MS (mass spectrometry). The characteristic ion peaks m/z (M+15)+ of naphthenic acid esters combined with z-series formula CnH2n+zO2 of naphthenic acids can be used to classify naphthenic acids into fatty acids, mono-cyclic, bi-cyclic, tri-cyclic, and higher polycyclic acids. The analytical results can give the molecular weight and the carbon number distribution of petroleum acids contained in crude oil. The results of study indicate that this method is simple, rapid and easy in operation.
文摘The concept of SBCR was put forward to treat sauce wastewater. Further study showed that adding appropriate amount of calcium chloride to SBR can improve the quality of effluent. The removal rate of COD and color was 84% and 80%, 36%, 96% higher than those of traditional SBR respectively. The results of continuous experiments and biophase observing showed that calcium chloride accumulation increased the sludge production slightly while the sludge dewatering characteristic was improved.
文摘Experimental design was applied in the optimization of crude oil adsorption from saline waste water using raw bagasse.The application of response surface methodology(RSM) was presented with temperature,salinity of water,pH,adsorbent dose,and initial oil content as factors.A quadratic model could be used to approximate the mathematical relationship of crude oil removal on the five significant independent variables.Predicted values and experimental values are found to be in good agreement with R2 of 97.44%.The result of optimization shows that the maximum crude oil removal is equal to 67.38% under the optimal condition of temperature of 46.53 °C,salinity of 37.2 g/L,pH of 3,adsorbent dose of 9 g/L and initial oil content of 300×10-6.
文摘After conducting a lot of screening experiments the appropriate flocculating formulations for treating high-concentration wastewater discharged from a certain refinery were selected. The oil removal rate and COD removal achieved by these flocculating formulations were better than that achieved by the conventional compound formulation consisting of polyaluminium chloride(PAC) and polyacrylamide(PAA) . Addition of an oil/water separating agent to the formulation could improve its oil removal performance to facilitate the oil/water separation of the oil-in-water emulsion in the high-concentration wastewater along with improved adaptability of the formulation to the wastewater containing high concentration of pollutants. This flocculating agent has promising prospects for commercial application.
文摘The aim of this work is to assess the short term effect of OMWW （olive mill waste water） application on chemical and biological soil properties. A field experiment was carried out in southern Tunisia. OMWW application was done at rates equivalent to 0, 15, 30 and 45 m^3/ha. Results showed that increasing rates of OMWW enhance the soil fertility due to its richness in organic matter such as N and P. A rapid increase of microbial biomass （during 14 days of incubation） of OMWW amended soils occurred. However, a high increase in salinity values and phenolic compounds concentrations was observed during this experiment.
文摘An economical and environmental sustainability of bioplastic production is dependent on the use of low cost and waste C-sources as raw materials. OMW （Olive Mill Wastewater） with its high organic load represents a dangerous polluting waste. Herein the authors present an integrated process for the simultaneous recovery of polyphenols, high value natural antioxidants, production of PHAs （polyhydroxyalkanotes）, thermoplastic bio-polymers, in particular of PHB （poly-3-hydroxybutyrate） starting from OMW. The combination of membrane filtration and bacterial digestion of OMW resulted in very high yields of polyphenols （3 2.5 g/L） and PHB （31.4 mg/L.h） if compared with the state of the art. These results make the technical approach described here effective for reducing the polluting effect of OMW and maximizing the valuable product yield. Moreover the process is readily suitable for an industrial scale PHB production from OMW.
文摘The aim of the present study was to implant an efficient strategy for controlling the level of the effluent-oily foam interface in a DAF （dissolved air flotation） chamber of a pilot-scale prototype. DAF has been successfully used in the treatment of oily water, which is one of the main environmental problems in different industrial facilities. Along with important operational parameters, such as microbubble size and flow rate, the control strategy for the automation of a DAF chamber may be an important tool for increasing efficiency. Controlling the level was the strategy chosen to enhance the separation efficiency in a pilot-scale DAF prototype, with monitoring performed using a computational program in LabVIEW （laboratory virtual instrument engineering workbench）. The findings demonstrate that it is possible to maintain the level of the fluid at a reference value established by the operator using the software program through the application of classic proportional integral derivative controllers. Using this control tool, the efficiency of water-oil separation in the pilot flotation chamber prototype was increased to nearly 98%.
