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2015 Vol. 33, No. 6
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2015, 33(6): 1-5.
doi: 10.13205/j.hjgc.201506001
Abstract:
With widely using of the nanotechnology，more and more nano-particles have entered into wastewater and sludge， which affect the anaerobic digestion process． Effects of nano-particles on anaerobic digestion process ( adsorption and reduction of harmful heavy metals，enhancing methane production as electron donor，degrading refractory organics and reducing hydrogen sulfide) and the impacts of nano-particles on anaerobic microorganisms ( releasing heavy metals toxicity，coating microbial cells by adsorption，damaging the cell membrane and DNA) were reviewed． In this paper，the strategies to reduce the harm of anaerobic microbes by nano-particles were discussed，in order to improve the anaerobic digestion of wastewater /sludge by taking advantage of nano-particles characteristics．
With widely using of the nanotechnology，more and more nano-particles have entered into wastewater and sludge， which affect the anaerobic digestion process． Effects of nano-particles on anaerobic digestion process ( adsorption and reduction of harmful heavy metals，enhancing methane production as electron donor，degrading refractory organics and reducing hydrogen sulfide) and the impacts of nano-particles on anaerobic microorganisms ( releasing heavy metals toxicity，coating microbial cells by adsorption，damaging the cell membrane and DNA) were reviewed． In this paper，the strategies to reduce the harm of anaerobic microbes by nano-particles were discussed，in order to improve the anaerobic digestion of wastewater /sludge by taking advantage of nano-particles characteristics．
2015, 33(6): 6-9.
doi: 10.13205/j.hjgc.201506002
Abstract:
Bioretention is a measure of LID with high efficiency to reduce rainwater from the source with decentralized approach and control the migration of pollutants． The status of foreign bioretention cell for urban stormwater runoff control in the aspect of hydrological effects，water treatment and models were reviewed． The prospects of domestic stormwater runoff control were as follows: Solving the dissolved N and granular suspended matter to meet the standard of water quality under proper hydraulic loading． The stability of bioretention under long running，including fillers such as secondary pollution and natural regeneration，should also be taken into consideration． Hydraulic and water quality models must be combined with the theoretical studies for reducing test cycles and optimizing the parameters of experiment．
Bioretention is a measure of LID with high efficiency to reduce rainwater from the source with decentralized approach and control the migration of pollutants． The status of foreign bioretention cell for urban stormwater runoff control in the aspect of hydrological effects，water treatment and models were reviewed． The prospects of domestic stormwater runoff control were as follows: Solving the dissolved N and granular suspended matter to meet the standard of water quality under proper hydraulic loading． The stability of bioretention under long running，including fillers such as secondary pollution and natural regeneration，should also be taken into consideration． Hydraulic and water quality models must be combined with the theoretical studies for reducing test cycles and optimizing the parameters of experiment．
2015, 33(6): 10-14.
doi: 10.13205/j.hjgc.201506003
Abstract:
The adsorption of molybdenum onto humus was studied by simulation． pH，time，temperature，dosing quantity and competitive anions were investigated during adsorption process． The adsorption mechanism was researched by the method of adsorption isotherm and kinetic model． The results showed that the removal efficiency of molybdenum from solution attached 90% at least，with pH ＜ 3，adsorptim time of 30 min，humus dosage 1 g，and a temperature of 25 ～ 30 ℃． The equilibrium adsorption capacity was 1. 014 mg/g at the optimum conditions． Phosphate appeared to compete strongly with MoO2 － 4 and the removal efficiency of molybdenum decreased from over 90% to 60% or so． Silicate and sulfate did a negligible effect on the sorption of MoO2 － 4 ． The Langmuir isotherm adsorption model and the pseudo second-order rate equation could fit the experimental data well． It meant that adsorption molybdenum onto humus was chemical adsorption and was controlled by chemical reactor． The conclusion showed that humus could be applied in adsorption of molybdenum in the future．
The adsorption of molybdenum onto humus was studied by simulation． pH，time，temperature，dosing quantity and competitive anions were investigated during adsorption process． The adsorption mechanism was researched by the method of adsorption isotherm and kinetic model． The results showed that the removal efficiency of molybdenum from solution attached 90% at least，with pH ＜ 3，adsorptim time of 30 min，humus dosage 1 g，and a temperature of 25 ～ 30 ℃． The equilibrium adsorption capacity was 1. 014 mg/g at the optimum conditions． Phosphate appeared to compete strongly with MoO2 － 4 and the removal efficiency of molybdenum decreased from over 90% to 60% or so． Silicate and sulfate did a negligible effect on the sorption of MoO2 － 4 ． The Langmuir isotherm adsorption model and the pseudo second-order rate equation could fit the experimental data well． It meant that adsorption molybdenum onto humus was chemical adsorption and was controlled by chemical reactor． The conclusion showed that humus could be applied in adsorption of molybdenum in the future．
2015, 33(6): 15-18.
doi: 10.13205/j.hjgc.201506004
Abstract:
During simulated dyeing and printing wastewater treatment，the characteristics of MBＲ five-pore hollow fiber membrane fouling in terms of hydraulics were studied． In order to test the changes of TMP，which was a key characteristic on membrane fouling，the experiment was carried out under the aeration intensity condition ranging from 25 L/h to 100 L/h and water flux condition ranging from 9 L/( m2·h) to 18 L/( m2·h) ． The results indicated that when the water flux was stable，the increasing of aeration intensity in a certain range could mitigate membrane fouling effectively and prolong the membrane running time; when aeration intensity was stable under sub-critical flux，the TMP's growth rate gradually reduced along with decreasing of water flux，namely the membrane running time was prolonged． This study provided valuable data of the membrane fouling control as well as the optimization of hydraulic conditions．
During simulated dyeing and printing wastewater treatment，the characteristics of MBＲ five-pore hollow fiber membrane fouling in terms of hydraulics were studied． In order to test the changes of TMP，which was a key characteristic on membrane fouling，the experiment was carried out under the aeration intensity condition ranging from 25 L/h to 100 L/h and water flux condition ranging from 9 L/( m2·h) to 18 L/( m2·h) ． The results indicated that when the water flux was stable，the increasing of aeration intensity in a certain range could mitigate membrane fouling effectively and prolong the membrane running time; when aeration intensity was stable under sub-critical flux，the TMP's growth rate gradually reduced along with decreasing of water flux，namely the membrane running time was prolonged． This study provided valuable data of the membrane fouling control as well as the optimization of hydraulic conditions．
2015, 33(6): 19-23.
doi: 10.13205/j.hjgc.201506005
Abstract:
With the control of point source pollution，non-point source ( NPS) pollution has become the dominant source which affects water quality due to its multi-source，wide distribution，controlling difficulties and so on． Production and transportation mechanism of NPS pollution is the basis of quantitative study，model simulation and pollution control． Moreover，it is also an important and difficult issue in the field of NPS pollution research． According to the previous researches，rainfall is the driving force of NPS pollution，and topography is the main influencing factor of NPS pollution． As for the two important factors，a lot of researches concerning their influence on the production and transportation of NPS pollution have been carried out at home and abroad nowadays． In this article，such researches were reviewed so as to provide a reference for related studies．
With the control of point source pollution，non-point source ( NPS) pollution has become the dominant source which affects water quality due to its multi-source，wide distribution，controlling difficulties and so on． Production and transportation mechanism of NPS pollution is the basis of quantitative study，model simulation and pollution control． Moreover，it is also an important and difficult issue in the field of NPS pollution research． According to the previous researches，rainfall is the driving force of NPS pollution，and topography is the main influencing factor of NPS pollution． As for the two important factors，a lot of researches concerning their influence on the production and transportation of NPS pollution have been carried out at home and abroad nowadays． In this article，such researches were reviewed so as to provide a reference for related studies．
2015, 33(6): 24-29.
doi: 10.13205/j.hjgc.201506006
Abstract:
In view of the increasingly serious pollution of urban inland river，a diversion scheme was developed and the corresponding experiments were conducted by taking Huancheng Ｒiver in the old city region of Chaohu as the object． According to the hydrology and water quality，six water quality monitoring stations were set up and Huancheng Ｒiver was divided into five sections． Based on the data of the hydrology and water quality，estimates were made in loads of nitrogen pollutants at different time in the five sections． Then preliminary studies were carried out on the load regularity of NH3－N and TN in each section． By comparing the removal efficiency of nitrogen pollutant loads in sections of upstream and downstream，factors affecting water diversion were analyzed in combination with the actual situation． As for the deficiencies in water diversion，four optimization suggestions about the program were proposed． And the effectiveness of the most viable option in them was verified．
In view of the increasingly serious pollution of urban inland river，a diversion scheme was developed and the corresponding experiments were conducted by taking Huancheng Ｒiver in the old city region of Chaohu as the object． According to the hydrology and water quality，six water quality monitoring stations were set up and Huancheng Ｒiver was divided into five sections． Based on the data of the hydrology and water quality，estimates were made in loads of nitrogen pollutants at different time in the five sections． Then preliminary studies were carried out on the load regularity of NH3－N and TN in each section． By comparing the removal efficiency of nitrogen pollutant loads in sections of upstream and downstream，factors affecting water diversion were analyzed in combination with the actual situation． As for the deficiencies in water diversion，four optimization suggestions about the program were proposed． And the effectiveness of the most viable option in them was verified．
2015, 33(6): 30-34.
doi: 10.13205/j.hjgc.201506007
Abstract:
Research on the microbial treatment of radioactive waste water and solide and its application have become to wide attention at home and abroad． Compared to solidification process，it is more efficient and more eco-friendly． The practice can be achieved by studying the behavior of microbial adsorption of radionuclides． The paper reviewed the radionuclide adsorption mechanisms，microbial factors which affect the adsorption behavior and adsorption behavior of microbial cells pretreated and other aspects of the nuclides，discussed the practical application of microbial adsorption of radionuclides currently
Research on the microbial treatment of radioactive waste water and solide and its application have become to wide attention at home and abroad． Compared to solidification process，it is more efficient and more eco-friendly． The practice can be achieved by studying the behavior of microbial adsorption of radionuclides． The paper reviewed the radionuclide adsorption mechanisms，microbial factors which affect the adsorption behavior and adsorption behavior of microbial cells pretreated and other aspects of the nuclides，discussed the practical application of microbial adsorption of radionuclides currently
2015, 33(6): 35-38.
doi: 10.13205/j.hjgc.201506008
Abstract:
Generally，because of karst growth， the velocity and direction of groundwater has great difference in space in the karst area． So the build-up of numerical model for simulating the groundwater flow and solute transport is very difficult． However，in practice，the movement rules of fissure water in the dolomite was found to conform to that in pore water． At the same time，solute transport mechanism conforms to basic conditions required for the diffusion theory． Taking an industrial site in Songtao County as an example，it was studied the dispersion parameter of groundwater quality in the dolomite formation and verified the numerical model through the field test． Visual MODFLOW computer software was used to establish the numerical model． Through the verification，the numerical method could simulate groundwater flow and solute transport in argillaceous dolomite stratum．
Generally，because of karst growth， the velocity and direction of groundwater has great difference in space in the karst area． So the build-up of numerical model for simulating the groundwater flow and solute transport is very difficult． However，in practice，the movement rules of fissure water in the dolomite was found to conform to that in pore water． At the same time，solute transport mechanism conforms to basic conditions required for the diffusion theory． Taking an industrial site in Songtao County as an example，it was studied the dispersion parameter of groundwater quality in the dolomite formation and verified the numerical model through the field test． Visual MODFLOW computer software was used to establish the numerical model． Through the verification，the numerical method could simulate groundwater flow and solute transport in argillaceous dolomite stratum．
2015, 33(6): 39-43.
doi: 10.13205/j.hjgc.201506009
Abstract:
In the research of optimizing the laying density of carbon fiber in remediation black-odorous water，with the help of the statistical software ( SIMCA-P) ，this paper explored the difference of the single indicator optimization method and principal component analysis method by using four factors ( COD，TP，NH3－N and TN) as analysis variables． The results showed that: Single indicator optimization method could confirm the best laying density of the four indicators respectively，while principal component analysis method could comprehensively analyze the information of four indicators and confirm the best carbon fiber laying density as 40 cm2 /L． The study could provide reference for the integrated use of carbon fiber．
In the research of optimizing the laying density of carbon fiber in remediation black-odorous water，with the help of the statistical software ( SIMCA-P) ，this paper explored the difference of the single indicator optimization method and principal component analysis method by using four factors ( COD，TP，NH3－N and TN) as analysis variables． The results showed that: Single indicator optimization method could confirm the best laying density of the four indicators respectively，while principal component analysis method could comprehensively analyze the information of four indicators and confirm the best carbon fiber laying density as 40 cm2 /L． The study could provide reference for the integrated use of carbon fiber．
2015, 33(6): 44-48.
doi: 10.13205/j.hjgc.201506010
Abstract:
With the acceleration urbanization process，the quality of urban aquifer groundwater is gradually becoming worse． An important metropolis in North China was selected as the study object． The sptio-temporal variability properties of total hardness of aquifer groundwater at four time points( 1980， 1990， 2000 and 2010) were analyzed based on ArcGIS． The results showed that during 1980—2010，the phreatic aquifer area with high concentration of total hardness increased greatly in research area，and the worse trend of groundwater was very obvious． The old city zone went through two phases: The rapid increase during 1980—1990 and stable status with slight decline after 1990． For the extended area of the city，the total hardness in the phreatic aquifer generally presented sluggish early and quick later increasing trend as a whole．
With the acceleration urbanization process，the quality of urban aquifer groundwater is gradually becoming worse． An important metropolis in North China was selected as the study object． The sptio-temporal variability properties of total hardness of aquifer groundwater at four time points( 1980， 1990， 2000 and 2010) were analyzed based on ArcGIS． The results showed that during 1980—2010，the phreatic aquifer area with high concentration of total hardness increased greatly in research area，and the worse trend of groundwater was very obvious． The old city zone went through two phases: The rapid increase during 1980—1990 and stable status with slight decline after 1990． For the extended area of the city，the total hardness in the phreatic aquifer generally presented sluggish early and quick later increasing trend as a whole．
2015, 33(6): 49-53.
doi: 10.13205/j.hjgc.201506011
Abstract:
In order to study the rule of pollution parameter of water quality by municipal sludge leachate changed over times and temperatures，and the thermal effect of sludge under anaerobic digestion，the paper determinated the change of pH value， contents of dissolved oxygen ( DO) ，total nitrogen ( TN) and total organic carbon ( TOC) of sludge leachate under anaerobic digestion at 30 ℃，45 ℃ and 60 ℃ separately，and also analyzed the effect of leachate pollution parameter． The curve of TGDTA was drawn by thermogravimetry and differential thermal tests under the temperature of 45 ℃， and the thermal effect was discussed． pH of sludge leachate was 7. 50 at begining，as the anaerobic fermentation in 30 ℃，the pH increased by 25. 7% and DO，TN，TOC decreased by 90. 0%，90. 4%， 74. 9% separately． The higer ambient temperature was，the faster reaction rate was． By the curve of TG-DTA，the loss of weight was caused by water desorption and organic burning，along with absorption and release of heat．
In order to study the rule of pollution parameter of water quality by municipal sludge leachate changed over times and temperatures，and the thermal effect of sludge under anaerobic digestion，the paper determinated the change of pH value， contents of dissolved oxygen ( DO) ，total nitrogen ( TN) and total organic carbon ( TOC) of sludge leachate under anaerobic digestion at 30 ℃，45 ℃ and 60 ℃ separately，and also analyzed the effect of leachate pollution parameter． The curve of TGDTA was drawn by thermogravimetry and differential thermal tests under the temperature of 45 ℃， and the thermal effect was discussed． pH of sludge leachate was 7. 50 at begining，as the anaerobic fermentation in 30 ℃，the pH increased by 25. 7% and DO，TN，TOC decreased by 90. 0%，90. 4%， 74. 9% separately． The higer ambient temperature was，the faster reaction rate was． By the curve of TG-DTA，the loss of weight was caused by water desorption and organic burning，along with absorption and release of heat．
2015, 33(6): 54-58.
doi: 10.13205/j.hjgc.201506012
Abstract:
In order to study the adsorption efficiency of petroleum hydrocarbon by chemical modified walnut shell，this paper used modified walnut shell as adsorbent and discussed the effects of initial pH value，adsorption time and temperature on the process． The results showed that the maximal adsorption capacity was up to 12. 57 mg /g under the conditions of pH of 7. 0， adsorption time of 80 min，temperature of 298 K and 0. 2 g of modified walnut shell mixed with 100mL of 60 mg /L diesel solution． The pseudo-second order kinetic model could provide a better correlation to the adsorption，the coefficient was 0. 9999． The isothermal adsorption was tested under the three temperature ( i． e． 298，308，318 K) ，freundlich model was more suitable to describe the process rather than Langmuir model． The thermodynamics values indicated that the adsorption process was endothermic and spontaneous． To some extent，the adsorption capacity enhanced with the increasing of temperature．
In order to study the adsorption efficiency of petroleum hydrocarbon by chemical modified walnut shell，this paper used modified walnut shell as adsorbent and discussed the effects of initial pH value，adsorption time and temperature on the process． The results showed that the maximal adsorption capacity was up to 12. 57 mg /g under the conditions of pH of 7. 0， adsorption time of 80 min，temperature of 298 K and 0. 2 g of modified walnut shell mixed with 100mL of 60 mg /L diesel solution． The pseudo-second order kinetic model could provide a better correlation to the adsorption，the coefficient was 0. 9999． The isothermal adsorption was tested under the three temperature ( i． e． 298，308，318 K) ，freundlich model was more suitable to describe the process rather than Langmuir model． The thermodynamics values indicated that the adsorption process was endothermic and spontaneous． To some extent，the adsorption capacity enhanced with the increasing of temperature．
2015, 33(6): 59-62.
doi: 10.13205/j.hjgc.201506013
Abstract:
In order to find out the optimum range of pH value for anammox reaction，simulated wastewater was used to study the effect of different pH，DO concentration on the performance of anammox reactor for Nitrogen removal in an ASBＲ reactor． And it is investigated that the effect of higher DO concentration on the performance of anaerobic ammonia oxidation sludge for nitrogen removal and the resistance capacity of anammox sludge against high DO concentration． The result shows that the optimum range of pH value for anaerobic ammonia oxidation reactor is 7. 5 ～ 8. 0，and its nitrogen removal performance is good and stable within this range: the removal rate of NH + 4 －N reached 90. 2%，and the NO － 2 －N removal rate reached 91. 1%． And anammox bacteria are very sensitive to oxygen content． There is significant inhibition effect when the DO in water is too high，but anaerobic ammonia oxidation reactor nitrogen removal efficiency can rapidly recovered when DO concentration being under control．
In order to find out the optimum range of pH value for anammox reaction，simulated wastewater was used to study the effect of different pH，DO concentration on the performance of anammox reactor for Nitrogen removal in an ASBＲ reactor． And it is investigated that the effect of higher DO concentration on the performance of anaerobic ammonia oxidation sludge for nitrogen removal and the resistance capacity of anammox sludge against high DO concentration． The result shows that the optimum range of pH value for anaerobic ammonia oxidation reactor is 7. 5 ～ 8. 0，and its nitrogen removal performance is good and stable within this range: the removal rate of NH + 4 －N reached 90. 2%，and the NO － 2 －N removal rate reached 91. 1%． And anammox bacteria are very sensitive to oxygen content． There is significant inhibition effect when the DO in water is too high，but anaerobic ammonia oxidation reactor nitrogen removal efficiency can rapidly recovered when DO concentration being under control．
2015, 33(6): 63-66.
doi: 10.13205/j.hjgc.201506014
Abstract:
High flocculating activity strains were screened and cultivated from activated sludge，water sediment，plant roots soil and strawberry planting soil． The flocculating activity of the strains was investigated by changing fermentation liquid dosage，coagulant dosage，carbon and nitrogen sources，and applied in the heavy metal wastewater treatment． The results showed that the strain QB1 can reach the highest flocculation rate of 93%，when using glucose as carbon source and yeast extract as nitrogen source，with the bacteria liquid dosage of 0. 2 mL，and coagulant dosage of 0. 8 mL． The removal rate of lead ion from the wastewater can be as high as 99% above．
High flocculating activity strains were screened and cultivated from activated sludge，water sediment，plant roots soil and strawberry planting soil． The flocculating activity of the strains was investigated by changing fermentation liquid dosage，coagulant dosage，carbon and nitrogen sources，and applied in the heavy metal wastewater treatment． The results showed that the strain QB1 can reach the highest flocculation rate of 93%，when using glucose as carbon source and yeast extract as nitrogen source，with the bacteria liquid dosage of 0. 2 mL，and coagulant dosage of 0. 8 mL． The removal rate of lead ion from the wastewater can be as high as 99% above．
2015, 33(6): 67-70.
doi: 10.13205/j.hjgc.201506015
Abstract:
Diesel particulate filter( DPF) is one of the most effective after-treatment technologies for diesel exhaust particulate pollution． It is a important measure to meet strict automotive diesel engine emission regulations in the future． DPF purification mechanism was introduced in this paper． The research status of the regeneration technologies of DPF in recent years were discussed and various regeneration technologies principle and its existing problems were discussed． At last，the research direction of DPF regeneration technologies in the future was put forward
Diesel particulate filter( DPF) is one of the most effective after-treatment technologies for diesel exhaust particulate pollution． It is a important measure to meet strict automotive diesel engine emission regulations in the future． DPF purification mechanism was introduced in this paper． The research status of the regeneration technologies of DPF in recent years were discussed and various regeneration technologies principle and its existing problems were discussed． At last，the research direction of DPF regeneration technologies in the future was put forward
2015, 33(6): 71-75.
doi: 10.13205/j.hjgc.201506016
Abstract:
Climate，the basic requirement of as human survival activities and development，its change is also bound to influence the complex ecosystem combined with“social-economy-eco-environment subsystem”． At the same time，in the process of urban construction，population growth，economic development，and spatial expansion，resources such as energy consumption had some side effects on climate changes． Based on the combination of qualitative and quantitative analysis methods，the coupling relationship between indicators of climate change and urban system was established． Taking Nanjing as an example，using the Spearman correlation coefficient to construct a interaction model，the coupling relationship was revealed quantitatively．
Climate，the basic requirement of as human survival activities and development，its change is also bound to influence the complex ecosystem combined with“social-economy-eco-environment subsystem”． At the same time，in the process of urban construction，population growth，economic development，and spatial expansion，resources such as energy consumption had some side effects on climate changes． Based on the combination of qualitative and quantitative analysis methods，the coupling relationship between indicators of climate change and urban system was established． Taking Nanjing as an example，using the Spearman correlation coefficient to construct a interaction model，the coupling relationship was revealed quantitatively．
2015, 33(6): 76-79.
doi: 10.13205/j.hjgc.201506017
Abstract:
Environmental pollution of cement industry is extremely serious． The source and evaluation method of atmospheric pollutant from cement industry was reviewed and analyzed． Through the time-scale and space-scale comparison in cement industry，it was found that in the past decade，the emission of dust，SO2 and NOx from cement industry increased with the increasing of cement production． Atmospheric pollutant emission of cement industry in Eastern China was the largest in the seven regions，in which the emission of dust，SO2 and NOx contributed 31. 8%，31. 0% and 31. 8% to the total emission of the whole industry，respectively．
Environmental pollution of cement industry is extremely serious． The source and evaluation method of atmospheric pollutant from cement industry was reviewed and analyzed． Through the time-scale and space-scale comparison in cement industry，it was found that in the past decade，the emission of dust，SO2 and NOx from cement industry increased with the increasing of cement production． Atmospheric pollutant emission of cement industry in Eastern China was the largest in the seven regions，in which the emission of dust，SO2 and NOx contributed 31. 8%，31. 0% and 31. 8% to the total emission of the whole industry，respectively．
2015, 33(6): 80-83.
doi: 10.13205/j.hjgc.201506018
Abstract:
The treatment for PM2. 5 has been paid more and more attention all around the world for its characteristics，such as small size，strong adsorption ability，long transportation range，great effect on atmosphere and difficulties in trapping ． With silicon carbide ceramic membrane tube coated with alumina ( porosity: 28. 16%，the average pore diameter: 20 μm，filter area: 0. 28 m2 ) as filter element，an experimental device was set up for trapping PM2. 5 ． The relationship between the filter time，flux and pressure drop，collection efficiency，cleaning pressure and cleaning time were studied． The results showed that the flux reduced gradually，the pressure drop and the collection efficiency increased with the filter time，and the collection efficiency for PM2. 5 was up to 99. 9%． The optimization parameters for membrane fouling control were the cleaning pressure 0. 8 MPa，the cleaning interval 10 min and the cleaning time 14 s，respectively．
The treatment for PM2. 5 has been paid more and more attention all around the world for its characteristics，such as small size，strong adsorption ability，long transportation range，great effect on atmosphere and difficulties in trapping ． With silicon carbide ceramic membrane tube coated with alumina ( porosity: 28. 16%，the average pore diameter: 20 μm，filter area: 0. 28 m2 ) as filter element，an experimental device was set up for trapping PM2. 5 ． The relationship between the filter time，flux and pressure drop，collection efficiency，cleaning pressure and cleaning time were studied． The results showed that the flux reduced gradually，the pressure drop and the collection efficiency increased with the filter time，and the collection efficiency for PM2. 5 was up to 99. 9%． The optimization parameters for membrane fouling control were the cleaning pressure 0. 8 MPa，the cleaning interval 10 min and the cleaning time 14 s，respectively．
2015, 33(6): 84-88.
doi: 10.13205/j.hjgc.201506019
Abstract:
The removal efficiency of NO has become the bottleneck of the development of double towers system for simultaneous biological removal of SO2 and NOx ． In order to increase the microbial removal rates of NO and NOx from the flue gas，a solution of FeSO4·7H2O was added into the desulfurizing tower， and a certain concentration solution of NaNO2 was added into the denitrification tower，which were investigated on the effects on double towers system． The results demonstrated that the mean removal rates ( Abbrev． rates) of NO was 61. 04% when the dosage of FeSO4·7H2O was 0. 23 g /L， increasing by 25. 73% compared with blank test; the removal rates of NOx was 62. 16% in desulfurizing tower，which increased 31. 06% than the blank test; and the capacity of purifying NOx of double towers system improved from 61. 8% to 86. 9%． The concentration gradient experiment results showed that the suitable concentration of FeSO4·7H2O was 0. 23 g /L． Besides， the removal rate of NO by denitrification tower increased from 39. 92% to 52. 11% with the dosage of NaNO2 being 0. 5 g /L; and the NOx removal rate increased from 47. 67% to 58. 90%． Meanwhile，the removal rate of NOx in the double towers system was 79. 32%，while the blank test was 70. 75%． Verification tests for many times proved that adding FeSO4 and NaNO2 could enhance the microbial purification efficiency of NO and NOx in simulated flue gas．
The removal efficiency of NO has become the bottleneck of the development of double towers system for simultaneous biological removal of SO2 and NOx ． In order to increase the microbial removal rates of NO and NOx from the flue gas，a solution of FeSO4·7H2O was added into the desulfurizing tower， and a certain concentration solution of NaNO2 was added into the denitrification tower，which were investigated on the effects on double towers system． The results demonstrated that the mean removal rates ( Abbrev． rates) of NO was 61. 04% when the dosage of FeSO4·7H2O was 0. 23 g /L， increasing by 25. 73% compared with blank test; the removal rates of NOx was 62. 16% in desulfurizing tower，which increased 31. 06% than the blank test; and the capacity of purifying NOx of double towers system improved from 61. 8% to 86. 9%． The concentration gradient experiment results showed that the suitable concentration of FeSO4·7H2O was 0. 23 g /L． Besides， the removal rate of NO by denitrification tower increased from 39. 92% to 52. 11% with the dosage of NaNO2 being 0. 5 g /L; and the NOx removal rate increased from 47. 67% to 58. 90%． Meanwhile，the removal rate of NOx in the double towers system was 79. 32%，while the blank test was 70. 75%． Verification tests for many times proved that adding FeSO4 and NaNO2 could enhance the microbial purification efficiency of NO and NOx in simulated flue gas．
2015, 33(6): 89-911.
doi: 10.13205/j.hjgc.201506020
Abstract:
The characteristics of flue gas desulfurization using modified double-recycling and multi-stage water film tower was evaluated in this paper． In order to increase the SO2 removal efficiency，contact probability of liquid phase and flue gas was enlarged through using multi-point pH control and multi-stage water film． Factors such as flue gas velocity，pH of upper and lower tower section，ratio of liquid-flue gas and inlet SO2 concentration were selected to research the desulfurization effect． The result showed that SO2 removal efficiency kept above 93% when the inlet SO2 concentration was less than 5 000 mg /m3 ． There was no aggradation of CaSO4 or CaSO3 under the optimized pH condition of 6. 0 and 5. 0 for the upper and lower section of the tower，and 15 of L/G． The system has a favorable future of application，and a considerable reference for debugging and running of spot desulfurization equipments．
The characteristics of flue gas desulfurization using modified double-recycling and multi-stage water film tower was evaluated in this paper． In order to increase the SO2 removal efficiency，contact probability of liquid phase and flue gas was enlarged through using multi-point pH control and multi-stage water film． Factors such as flue gas velocity，pH of upper and lower tower section，ratio of liquid-flue gas and inlet SO2 concentration were selected to research the desulfurization effect． The result showed that SO2 removal efficiency kept above 93% when the inlet SO2 concentration was less than 5 000 mg /m3 ． There was no aggradation of CaSO4 or CaSO3 under the optimized pH condition of 6. 0 and 5. 0 for the upper and lower section of the tower，and 15 of L/G． The system has a favorable future of application，and a considerable reference for debugging and running of spot desulfurization equipments．
2015, 33(6): 92-97.
doi: 10.13205/j.hjgc.201506021
Abstract:
Cement molding and sintering of MSW fly ash were carried out，and XＲD/SEM were applied to seek the sintering mechanism and the effect of fluxing agent． The results showed that Na2CO3 could accelerate fly ash solidification during the early phase of cement molding，but showed negative influence with the solidification time increased; With a curing time of 2 d， the compressive strength of cement solidified body reached 1. 91 MPa，completely meeting the intensity requirements of making bad body; XＲD and SEM analysis results showed that the solidified body mainly produced gehlenite and calcium silicate during sintering，and Na2B4O7·10H2O had obvious fusion effect; The leaching concentrations of Ni，Cu，Pb and Cd reduced with sintering temperature increased，and leaching concentration of Cu and Cd increased with dosage of Na2B4O7·10H2O increased，but Pb decreased． The leaching experiment results showed that the leaching content of Ni，Cu，Pb and Cd were lower than the national standard limit．
Cement molding and sintering of MSW fly ash were carried out，and XＲD/SEM were applied to seek the sintering mechanism and the effect of fluxing agent． The results showed that Na2CO3 could accelerate fly ash solidification during the early phase of cement molding，but showed negative influence with the solidification time increased; With a curing time of 2 d， the compressive strength of cement solidified body reached 1. 91 MPa，completely meeting the intensity requirements of making bad body; XＲD and SEM analysis results showed that the solidified body mainly produced gehlenite and calcium silicate during sintering，and Na2B4O7·10H2O had obvious fusion effect; The leaching concentrations of Ni，Cu，Pb and Cd reduced with sintering temperature increased，and leaching concentration of Cu and Cd increased with dosage of Na2B4O7·10H2O increased，but Pb decreased． The leaching experiment results showed that the leaching content of Ni，Cu，Pb and Cd were lower than the national standard limit．
2015, 33(6): 98-101.
doi: 10.13205/j.hjgc.201506022
Abstract:
Solid wastes co-processing using cement kilns becomes an effective way in building a resource-saving and eco friendly city． As a new technology，it combines the advantages of cement production and waste disposal together，and plays a important role in dealing with municipal waste． This article compares the difference of the co-processing status between China and Japan． It shows that China still have a long way to go in the field of waste category being co-processed，the substitute fuel level，regulations established and the government managerial system． According to the actual situation of China，some reasonable suggestions are put forward，such as promoting the development of concerning technologies，putting more emphasis on scientific research，improving the managerial system，etc．
Solid wastes co-processing using cement kilns becomes an effective way in building a resource-saving and eco friendly city． As a new technology，it combines the advantages of cement production and waste disposal together，and plays a important role in dealing with municipal waste． This article compares the difference of the co-processing status between China and Japan． It shows that China still have a long way to go in the field of waste category being co-processed，the substitute fuel level，regulations established and the government managerial system． According to the actual situation of China，some reasonable suggestions are put forward，such as promoting the development of concerning technologies，putting more emphasis on scientific research，improving the managerial system，etc．
2015, 33(6): 102-106.
doi: 10.13205/j.hjgc.201506023
Abstract:
This paper was designed to study the tendency of membrane fouling by using membrane critical flux． The response surface model was used to study different factors，such as sludge concentration，space between membranes and aeration rate， affecting membrane fouling of the upper and lower layer membrane module． It was found that the model was fitting and significant，moreover，the sludge concentration，space between membranes and aeration rate had a significant impact on the upper and lower membrane fouling． Meanwhile，it was also observed that the critical flux of both upper and lower layer membrane module sharply decreased with the increase of sludge concentration． However，the different variation tendency of membrane fouling between upper and lower layer membrane module was detected due to the change of space between membranes and aeration rate under different sludge concentration． Finally，optimum operating parameters under different sludge concentration simulated by response surface model were successfully applied to the process of using flat-sheet membrane for four-stage sludge thickening．
This paper was designed to study the tendency of membrane fouling by using membrane critical flux． The response surface model was used to study different factors，such as sludge concentration，space between membranes and aeration rate， affecting membrane fouling of the upper and lower layer membrane module． It was found that the model was fitting and significant，moreover，the sludge concentration，space between membranes and aeration rate had a significant impact on the upper and lower membrane fouling． Meanwhile，it was also observed that the critical flux of both upper and lower layer membrane module sharply decreased with the increase of sludge concentration． However，the different variation tendency of membrane fouling between upper and lower layer membrane module was detected due to the change of space between membranes and aeration rate under different sludge concentration． Finally，optimum operating parameters under different sludge concentration simulated by response surface model were successfully applied to the process of using flat-sheet membrane for four-stage sludge thickening．
2015, 33(6): 107-111.
doi: 10.13205/j.hjgc.201506024
Abstract:
A strain of Thiobacillus ferrooxidans ( T． f) was successfully isolated from the acidic sediment of a pyrite mine in Tianjin． And the strain was identified by its morphology and DNA sequence． Moreover，the paper researched bioleaching of heavy metals in estuarine sediment． The results demonstrated that T． f could start bioleaching quickly and heavy metals could be removed efficiently by bioleaching technology． And with 7 g /L of ferrous sulfate，15% of sludge-inoculation ratio，30 ℃ of temperature，and 3 g /L of sulfur，the maximum removal efficiencies of Cu，Zn and Hg were 80. 6%，63. 9% and 82. 5% respectively．
A strain of Thiobacillus ferrooxidans ( T． f) was successfully isolated from the acidic sediment of a pyrite mine in Tianjin． And the strain was identified by its morphology and DNA sequence． Moreover，the paper researched bioleaching of heavy metals in estuarine sediment． The results demonstrated that T． f could start bioleaching quickly and heavy metals could be removed efficiently by bioleaching technology． And with 7 g /L of ferrous sulfate，15% of sludge-inoculation ratio，30 ℃ of temperature，and 3 g /L of sulfur，the maximum removal efficiencies of Cu，Zn and Hg were 80. 6%，63. 9% and 82. 5% respectively．
2015, 33(6): 112-115.
doi: 10.13205/j.hjgc.201506025
Abstract:
A simulation of atmospheric dispersion of air pollutants in Hainan Province was carried out by employing CALPUFF model， and the atmospheric environmental capacity of SO2 and PM10 was estimated based on the results of model simulation and using multi-objective linear programming optimization． The results indicated that the air pollution in Hainan province was significantly related to the pollution sources outside of Hainan province in spring， autumn and winter，and the pollution source inside of Hainan province in spring and summer had higher contribution than that in autumn and winter． To meet the requirement of ambient air quality standard， the environmental capacities of PM10 and SO2 in major industrial park of Hainan province were only 7. 32 × 104 t and 6. 38 × 104 t， respectively．
A simulation of atmospheric dispersion of air pollutants in Hainan Province was carried out by employing CALPUFF model， and the atmospheric environmental capacity of SO2 and PM10 was estimated based on the results of model simulation and using multi-objective linear programming optimization． The results indicated that the air pollution in Hainan province was significantly related to the pollution sources outside of Hainan province in spring， autumn and winter，and the pollution source inside of Hainan province in spring and summer had higher contribution than that in autumn and winter． To meet the requirement of ambient air quality standard， the environmental capacities of PM10 and SO2 in major industrial park of Hainan province were only 7. 32 × 104 t and 6. 38 × 104 t， respectively．
2015, 33(6): 116-120.
doi: 10.13205/j.hjgc.201506026
Abstract:
The release of nitrogen and phosphorus from upland is an important factor which leads to the eutrophication in aquatic ecosystems． The phosphate ores distributed in Xiangxi Ｒiver Watershed，west of Hubei，posed a serious impact on water quality of Xiangxi Ｒiver． The purposes of this study were to investigate the intrinsic relationship between soil enzyme activity and inorganic phosphorus ( IP) forms in the phosphorus-rich area of the Xiangxi Ｒiver watershed，and explore the feasibility of using soil enzyme system characterization of the magnitude of soil phosphorus pollution． Ｒesults showed that there was a significant relationship between soil enzyme activities and IP forms． The activities of catalase，sucrase and urease were significantly correlated to IP forms，while polyphenol oxidase and alkaline phosphatase activities were significantly and negatively correlated to IP forms． The activities of soil catalase，polyphenol oxidase，sucrase，urease and alkaline phosphatase showed different degrees of correlation with IP forms． The findings suggest that soil enzyme activity might be used as an indicator for the magnitude of soil phosphorus pollution in the phosphorus mineral region．
The release of nitrogen and phosphorus from upland is an important factor which leads to the eutrophication in aquatic ecosystems． The phosphate ores distributed in Xiangxi Ｒiver Watershed，west of Hubei，posed a serious impact on water quality of Xiangxi Ｒiver． The purposes of this study were to investigate the intrinsic relationship between soil enzyme activity and inorganic phosphorus ( IP) forms in the phosphorus-rich area of the Xiangxi Ｒiver watershed，and explore the feasibility of using soil enzyme system characterization of the magnitude of soil phosphorus pollution． Ｒesults showed that there was a significant relationship between soil enzyme activities and IP forms． The activities of catalase，sucrase and urease were significantly correlated to IP forms，while polyphenol oxidase and alkaline phosphatase activities were significantly and negatively correlated to IP forms． The activities of soil catalase，polyphenol oxidase，sucrase，urease and alkaline phosphatase showed different degrees of correlation with IP forms． The findings suggest that soil enzyme activity might be used as an indicator for the magnitude of soil phosphorus pollution in the phosphorus mineral region．
2015, 33(6): 121-124.
doi: 10.13205/j.hjgc.201506027
Abstract:
The paper established assessment indicator system with 17 indicators． The indicators could reflect the level of regional water resources carrying capacity based on natural geography and social economic conditions of Xiangyang City，the middle reaches of Hanjiang Ｒiver． Vector norm method was used to evaluate the water resources carrying capacity of Xiangyang during 2000 to 2012． The results indicated that the water resources carrying capacity leval of Xiangyang was relatively low， which varied from 0. 2939 to 0. 4114，but had a tendency of improvement． As the middle route of Chinese south-to-north water transfer project achieved water diversion for the first time in 2014，the contradiction between supply and demand of water resources would more prominent due to the reduction of discharged water． Ｒesearch results could provide theoretical reference and practical guiding for Xiangyang to use water resources appropriately and enhance ecological environment construction，so as to decrease the negative influence of water diversion and achieve sustainable development．
The paper established assessment indicator system with 17 indicators． The indicators could reflect the level of regional water resources carrying capacity based on natural geography and social economic conditions of Xiangyang City，the middle reaches of Hanjiang Ｒiver． Vector norm method was used to evaluate the water resources carrying capacity of Xiangyang during 2000 to 2012． The results indicated that the water resources carrying capacity leval of Xiangyang was relatively low， which varied from 0. 2939 to 0. 4114，but had a tendency of improvement． As the middle route of Chinese south-to-north water transfer project achieved water diversion for the first time in 2014，the contradiction between supply and demand of water resources would more prominent due to the reduction of discharged water． Ｒesearch results could provide theoretical reference and practical guiding for Xiangyang to use water resources appropriately and enhance ecological environment construction，so as to decrease the negative influence of water diversion and achieve sustainable development．
2015, 33(6): 125-128.
doi: 10.13205/j.hjgc.201506028
Abstract:
Continuous，online measurement of atmospheric greenhouse gases is not only an important part of research on global and regional carbon cycle as well as its climatic and environmental effects，but also the basis work of greenhouse gases emission reduction policy making and evaluation on effects of emission reduction in various regions． In this paper，in-situ monitoring methods of atmospheric greenhouse gases were summarized in terms of their principles and applications，and developing trend of greenhouse gas monitoring methods was put forward and discussed，which will provide reference for further development of greenhouse gas monitoring and methodological standardization．
Continuous，online measurement of atmospheric greenhouse gases is not only an important part of research on global and regional carbon cycle as well as its climatic and environmental effects，but also the basis work of greenhouse gases emission reduction policy making and evaluation on effects of emission reduction in various regions． In this paper，in-situ monitoring methods of atmospheric greenhouse gases were summarized in terms of their principles and applications，and developing trend of greenhouse gas monitoring methods was put forward and discussed，which will provide reference for further development of greenhouse gas monitoring and methodological standardization．
2015, 33(6): 129-132.
doi: 10.13205/j.hjgc.201506029
Abstract:
The paper proposed a noise evaluation model，NEM，aiming at large-scale area． The discrepancy caused by the noise in exposed crowds and varieties of noise environmental function areas was considered comprehensively and was made a hierarchical representation according to environmental quality standard for noise in city and the impact on people’s health by noise in the NEM model． Furthermore，in case study，an evaluation of Guangzhou’s noise condition was presented using NEM model． Contrasted with NPI method and NII method，the comparison of evaluation results indicated that to evaluate noise in environmental large-scale area the NEM model is scientific and reasonable，and reliable to get the conclusion．
The paper proposed a noise evaluation model，NEM，aiming at large-scale area． The discrepancy caused by the noise in exposed crowds and varieties of noise environmental function areas was considered comprehensively and was made a hierarchical representation according to environmental quality standard for noise in city and the impact on people’s health by noise in the NEM model． Furthermore，in case study，an evaluation of Guangzhou’s noise condition was presented using NEM model． Contrasted with NPI method and NII method，the comparison of evaluation results indicated that to evaluate noise in environmental large-scale area the NEM model is scientific and reasonable，and reliable to get the conclusion．
2015, 33(6): 133-138.
doi: 10.13205/j.hjgc.201506030
Abstract:
In this paper，the correlation between band combinations of Landsat5 /TM image and chlorophyll-a concentration has been studied after the image pre-processing of the TM of 23rd July，2009，and the correlation was low． Then the Wuliangsuhai Lake was divided into two areas according to water conservancy conditions and own characteristics of the lake， and the correlation between ( TM1 + TM2 + TM4) /TM3 ＆ TM4 /TM3 and chlorophyll-a concentration was high． Finally， chlorophyll-a concentration of Wuliangsuhai Lake was inversed by low error model which was established by ( TM1 + TM2 + TM4) /TM3． The model could accurately estimate chlorophyll-a concentration of Wuliangsuhai Lake， and satisfy the requirement for a real-time and rapid monitoring of chlorophyll-a concentration． This research will provide theoretical basis to dynamic monitoring and early warning of“Huang tai”algal bloom．
In this paper，the correlation between band combinations of Landsat5 /TM image and chlorophyll-a concentration has been studied after the image pre-processing of the TM of 23rd July，2009，and the correlation was low． Then the Wuliangsuhai Lake was divided into two areas according to water conservancy conditions and own characteristics of the lake， and the correlation between ( TM1 + TM2 + TM4) /TM3 ＆ TM4 /TM3 and chlorophyll-a concentration was high． Finally， chlorophyll-a concentration of Wuliangsuhai Lake was inversed by low error model which was established by ( TM1 + TM2 + TM4) /TM3． The model could accurately estimate chlorophyll-a concentration of Wuliangsuhai Lake， and satisfy the requirement for a real-time and rapid monitoring of chlorophyll-a concentration． This research will provide theoretical basis to dynamic monitoring and early warning of“Huang tai”algal bloom．
2015, 33(6): 139-143.
doi: 10.13205/j.hjgc.201506031
Abstract:
As a high energy-consuming industry，the energy loss reductions of communication base stations in telecom industry are attracting more attentions． Aiming at this problem，in this paper，a novel ventilation cooling system is proposed to reduce energy consumption，which combinates the chimney ventilation and the air-condition cooling． 3-D thermal-fluid field calculation is emploded to analyze the key factors affecting the ventilation． And orthogonal experiment is used to optimize the cooling structure parameters of the stations． To maximize to lower the operating temperature in the base stations，so as to reduce communication base stations operating cost．
As a high energy-consuming industry，the energy loss reductions of communication base stations in telecom industry are attracting more attentions． Aiming at this problem，in this paper，a novel ventilation cooling system is proposed to reduce energy consumption，which combinates the chimney ventilation and the air-condition cooling． 3-D thermal-fluid field calculation is emploded to analyze the key factors affecting the ventilation． And orthogonal experiment is used to optimize the cooling structure parameters of the stations． To maximize to lower the operating temperature in the base stations，so as to reduce communication base stations operating cost．
2015, 33(6): 144-147.
doi: 10.13205/j.hjgc.201506032
Abstract:
To avoid the oxidation of nano-Fe0 in the air，nanoparticles were immobilized in sodium alginate /β-cyclodextrin gelbeads． The effects of the ratio of raw materials and cross-linker concentration et al． on gel-beads properties were investigated． Optimal reactivity was received with the nano-Fe0 immobilized by 1. 5% SA，0. 5% β-CD and with 4. 0% CaCl2 as the crosslinker． Much higher removal efficiency was obtained in Pb2 + removal compared with Cd2 + ． Pb2 + ( 200 mg /L) with 99. 3% removal ratio was obtained after 4 h． Pb2 + was removed by gel-beads combined with Fe0 ． High reactivity was still achieved after 120 days with the immobilized nano-Fe0 ．
To avoid the oxidation of nano-Fe0 in the air，nanoparticles were immobilized in sodium alginate /β-cyclodextrin gelbeads． The effects of the ratio of raw materials and cross-linker concentration et al． on gel-beads properties were investigated． Optimal reactivity was received with the nano-Fe0 immobilized by 1. 5% SA，0. 5% β-CD and with 4. 0% CaCl2 as the crosslinker． Much higher removal efficiency was obtained in Pb2 + removal compared with Cd2 + ． Pb2 + ( 200 mg /L) with 99. 3% removal ratio was obtained after 4 h． Pb2 + was removed by gel-beads combined with Fe0 ． High reactivity was still achieved after 120 days with the immobilized nano-Fe0 ．
2015, 33(6): 148-152.
doi: 10.13205/j.hjgc.201506033
Abstract:
Phytoremediation is an effective approach for remediation and comprehensive control of heavy metal contamination in mining area． The research progress abroad in phytoremediation technology of heavy metal contaminations in mine degraded soils including phytostabilization，phytoextraction，phytovolatilisation，phytofiltration started early，while China fall far behind in the related research fields． Ｒecently，studies in China and abroad about the ecological remediation of rare earth mining are scarce，which should be strengthened in future．
Phytoremediation is an effective approach for remediation and comprehensive control of heavy metal contamination in mining area． The research progress abroad in phytoremediation technology of heavy metal contaminations in mine degraded soils including phytostabilization，phytoextraction，phytovolatilisation，phytofiltration started early，while China fall far behind in the related research fields． Ｒecently，studies in China and abroad about the ecological remediation of rare earth mining are scarce，which should be strengthened in future．
2015, 33(6): 153-157.
doi: 10.13205/j.hjgc.201506034
Abstract:
A biosurfactant-producing strain，named XJBM，was isolated from the oil contaminated soil of Karamay of field in Xinjiang，with crude oil as the sole carbon and energy source via enrichment culture． XJBM was identified as Pseudomonas Aeruginosa based on morphology，physiological and biochemical characteristics and the analysis of Biolog system． Glycolipid was found as the main components of the produced biosrfactant，which was examined by thin-layer chromatography． Under the optimal fermentation conditions，the yield of biosurfactant produced by XJBM could reach 2. 25 g /L． This biosurfactant could reduce the surface tension of culture broth from 68. 20mN/m to 32. 50 mN/m and emulsify paraffin oil to an appreciable level ( E24 = 81. 8%) ． The results of the single factor experiments showed that the optimum degradation conditions for strain XJBM were as follows: initial pH of 7. 5，temperature of 30 ℃，salt concentration of 5 g /L and inoculation amount of 10%． Under that condition，the degradation rate of strain XJBM for oil concentration with 1 g /L was 63. 78% after 7 days at shaking rate of 150 r /min．
A biosurfactant-producing strain，named XJBM，was isolated from the oil contaminated soil of Karamay of field in Xinjiang，with crude oil as the sole carbon and energy source via enrichment culture． XJBM was identified as Pseudomonas Aeruginosa based on morphology，physiological and biochemical characteristics and the analysis of Biolog system． Glycolipid was found as the main components of the produced biosrfactant，which was examined by thin-layer chromatography． Under the optimal fermentation conditions，the yield of biosurfactant produced by XJBM could reach 2. 25 g /L． This biosurfactant could reduce the surface tension of culture broth from 68. 20mN/m to 32. 50 mN/m and emulsify paraffin oil to an appreciable level ( E24 = 81. 8%) ． The results of the single factor experiments showed that the optimum degradation conditions for strain XJBM were as follows: initial pH of 7. 5，temperature of 30 ℃，salt concentration of 5 g /L and inoculation amount of 10%． Under that condition，the degradation rate of strain XJBM for oil concentration with 1 g /L was 63. 78% after 7 days at shaking rate of 150 r /min．
