[Background]The previous studies suggest that radioactive elements like Cs and Sr may adversely affect marine ecosystems and the fishing industry.Traditional treatment systems for radioactive wastewater like the Advan...[Background]The previous studies suggest that radioactive elements like Cs and Sr may adversely affect marine ecosystems and the fishing industry.Traditional treatment systems for radioactive wastewater like the Advanced Liquid Processing System(ALPS)and Kurion have faced challenges in limiting concentration and achieving safety criteria.Studies suggest potential long-term impacts on benthic organisms and seafood networks due to radioactive elements like Cs and Sr from the discharged radioactive wastewater,which may hinder post-disaster recovery and provoke economic losses in the fishing industry both domestically and internationally.A series of studies indicate that there are issues of Cs and Sr pollution migration in soil and water conservation in Fukushima.[Methods]To provide feasible solutions,the main article includes five nuclear wastewater treatment technologies,and soil and water conservation measures for different media(water and soil)were evaluated through reviewing the previous fifteen years'articles.To provide feasible solutions,the main articles,the phytoextraction technologies in Cs and Sr treatment within different land use areas were wildly analyzed(Camellia japonica,Arabidopsis halleri and other local species).[Results]1)A 99.9%removal rate for Cs^(+)and 99.5%for Sr^(2+)was achieved by the KFe[Fe(CN)_(6)]and BaSO_(4)co-precipitation method.2)For membrane filtration,Sr^(2+)and Cs^(+)were removed using metal-organic framework(MOF/graphene oxide)and ion exchange techniques using inorganic materials like titanosilicates.The absorption efficiency of membrane filtration for Sr^(2+)and Cs^(+)was at least 92%and 94%,respectively.The study analyzed soil and water conservation technologies in different land uses,river basins and catchments.3)The underground water treatment mainly were completed via the membrance technologies like reverse osmosis and Permeable Reactive Barriers(PRB)technologies.The ^(90) Sr concentration decreased 77%-91%compared to the initial concentration by PRB technology.These diverse methods offered effective strategies for radioactive wastewater treatment,especially the co-precipitation method may be feasible remediation measures to ensure ecological safety surrounding nuclear power utilizing areas.Soil and water conservation measures for soil pollution treatment mainly focused on the use of stabilizers to hinder the migration of Cs and Sr in the soil and the effects of wind erosion such as interpolyelectrolyte complexes.[Conclusions]We evaluated the pollution of Cs and Sr in the Fukushima nuclear radiation soil and water to provide solutions for the treatment of nuclear wastewater and to prevent radionuclide pollutants from migrating into the soil and water.展开更多
The experimental results of producing deionized water for the themoelectric factory from two types of the industrial wastewater of an alumina plant by using membrane technology are reported in this paper. For the trea...The experimental results of producing deionized water for the themoelectric factory from two types of the industrial wastewater of an alumina plant by using membrane technology are reported in this paper. For the treatment of the industrial wastewater with high salinity and pH value, the combination of electrodialysis (ED) and reverse osmosis (RO) is utilized, while for the treatment of the low salinity wastewater with low pH value, RO is directly used. The research results show that the above mentioned methods are effective. The technological process of the wastewater treatment with the capacity of 120 tons is designed on the basis of the experimental results.展开更多
A coupled system consisting of an upflow membrane-less microbial fuel cell (upflow ML-MFC) and a photobioreactor was developed, and its effectiveness for continuous wastewater treatment and electricity production was ...A coupled system consisting of an upflow membrane-less microbial fuel cell (upflow ML-MFC) and a photobioreactor was developed, and its effectiveness for continuous wastewater treatment and electricity production was evaluated. Wastewater was fed to the upflow ML-MFC to remove chemical oxygen demand (COD), phosphorus and nitrogen with simultaneous electricity generation. The effluent from the cathode compartment of the upflow ML-MFC was then continuously fed to an external photobioreactor for removing the remaining phosphorus and nitrogen using microalgae. Alone, the upflow ML-MFC produces a maximum power density of 481 mW/m 3 , and obtains 77.9% COD, 23.5% total phosphorus (TP) and 97.6% NH4+-N removals. When combined with the photobioreactor, the system achieves 99.3% TP and 99.0% NH4+-N total removal. These results show both the effectiveness and the potential application of the coupled system to continuously treat domestic wastewater and simultaneously generate electricity and biomass.展开更多
A laboratory scale up-flow biological activated carbon(BAC) reactor was constructed for the advanced treatment of synthetic flotation wastewater. Biodegradation of a common collector(i.e., ethyl xanthate) for non-ferr...A laboratory scale up-flow biological activated carbon(BAC) reactor was constructed for the advanced treatment of synthetic flotation wastewater. Biodegradation of a common collector(i.e., ethyl xanthate) for non-ferrous metallic ore flotation was evaluated. The results show that the two stages of domestication can improve microbial degradation ability. The BAC reactor obtains a chemical oxygen demand(COD) reduction rate of 82.5% for ethyl xanthate and its effluent COD concentration lowers to below 20 mg/L. The kinetics equation of the BAC reactor proves that the activated carbon layers at the height of 0 mm to 70 mm play a key role in the removal of flotation reagents. Ultraviolet spectral analysis indicates that most of the ethyl xanthate are degraded by microorganisms after advanced treatment by the BAC reactor.展开更多
The electrochemical treatment of wastewater containing chlorophenols （2-monochlorophenol, 4-monochlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol） was carried out experimentally with synthetic boron-d0ped diam...The electrochemical treatment of wastewater containing chlorophenols （2-monochlorophenol, 4-monochlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol） was carried out experimentally with synthetic boron-d0ped diamond （BDD） thin film electrodes. Current vs time curves under different cell voltages were measured. Removal rate of COD, instant current efficiency （ICE） and energy consumption were investigated under different current densities. The influence of supporting media is reported, which plays an important role in determining the global oxidation rate. The oxidative chloride is stronger than peroxodisulphate. The electrochemical characteristics of boron-doped diamond electrodes were investigated in comparison with active coating Ti substrate anode （ACT）. The experimental results show that BDD is markedly superior to ACT due to its different absorption properties.展开更多
Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment ...Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment of biologically pretreated coking wastewater. Particular attention was paid to the performance of the integrated system for the removal of chemical oxygen demand(COD), ammonia nitrogen(NH3-N) and total nitrogen(TN). The average removal efficiencies of COD, NH3-N and TN were 76.28%, 96.76% and 59.97%, with the average effluent mass concentrations of 56, 0.53 and 18.83 mg/L, respectively, reaching the first grade of the national discharge standard. Moreover, the results of gas chromatography/mass spectrum(GC/MS) and gel permeation chromatography(GPC) analysis demonstrated that the refractory organic compounds with high relative molecular mass were partly removed in IZVI process by the function of oxidation-reduction, flocculation and adsorption which could also enhance the biodegradability of the system effluent. The removal efficiencies of NH3-N and TN were achieved mainly in the subsequent AF/BAF reactors by nitrification and denitrification. Overall, the results obtained show that the application of IZVI in combination with AF/BAF is a promising technology for advanced treatment of biologically pretreated coking wastewater.展开更多
High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synth...High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synthetic high salinity wastewater was evaluated at laboratory scale during a 110-day operation.The reactor was operated in a 12 h cycle,and each cycle consisted of 0.25 h influent addition,8 h aeration,3 h anoxic reaction,0.5 h sedimentation and 0.25 h effluent withdrawal.Gradual increase in salinity gradient was applied during the acclimatization period.The acclimated SBBR system was demonstrated to be an effective process to remove organic compounds and ammonia nitrogen under high salinity conditions with chemical oxygen demand(COD)and ammonia nitrogen(NH3-N)removal efficiencies of 88% and 80%,respectively.The microscopic examination indicated that rather than rotifers or vorticella,the zoogloea,filamentous fungus mingled with a small quantity of swimming infusorians were dominant bacteria in SBBR system.The removal efficiencies close to 80% in COD and 75% in NH3-N were achieved at an organic loading rate(OLR)of 0.96 kg COD/(m3·d),pH of 7.0,salinity of 14 g/L and NH3-N of 30 mg/L.展开更多
The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6. Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu ...The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6. Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu to As was 2：1 and pH value of the neutralized wastewater was adjusted to 8.0 by sodium hydroxide. The arsenious acid solution and red residue were produced after copper arsenite mixed with water according to the ratio of liquid to solid of 4：1 and copper arsenite was reduced by SO2 at 60℃ for 1 h. The white powder was gained after the arsenious acid solution was evaporated and cooled. Copper sulfate solution was obtained after the red residue was leached by H2SO4 solution under the action of air. The results show that red residue is Cu3（SO3）2·2H2O and the white powder is As2O3. The leaching rate of Cu reaches 99.00% when the leaching time is 1.5 h, molar ratio of H2SO4 to Cu is 1.70, H2SO4 concentration is 24% and the leaching temperature is 80 ℃. The direct recovery rate of copper sulfate is 79.11% and the content of CuSOa·5H2O is up to 98.33% in the product after evaporating and cooling the copper sulfate solution.展开更多
Considering that Fe,Al elements in bauxite residue are active components for water purification,an effective polyaluminum ferric chloride(PAFC)coagulant derived from bauxite residue,with Fe2O3 content>5.1%,Al2O3%&g...Considering that Fe,Al elements in bauxite residue are active components for water purification,an effective polyaluminum ferric chloride(PAFC)coagulant derived from bauxite residue,with Fe2O3 content>5.1%,Al2O3%>6.5%,basicity>65%,was successfully prepared.The effect of as-prepared PAFC on the zeta potential for printing and dyeing wastewater was investigated.Comparing with polyferric chloride(PFC)and polyferric sulfate(PFS)for printing and dyeing wastewater treatment,prepared bauxite residue-based PAFC exhibited the optimal performance in the aspects of chromaticity and chemical oxygen demand(COD)removal rate.Furthermore,the combination of bauxite residue-based PAFC and PFS for synergy coagulation of such wastewater demonstrated an obvious positive effect.With the proportion between as-prepared PAFC and PFS to be 2.5:1,the COD of treated wastewater could be further reduced to meet the national level A standard of China,providing a promising route to solve the problem of substandard printing and dyeing sewage outfall by a simple coagulation strategy.展开更多
A full-scale experimental study of treating mustard wastewater by the integrated bioreactor with designed scale of 1 000 m3/d is conducted combined with a demonstration project. The systematical researches on the effi...A full-scale experimental study of treating mustard wastewater by the integrated bioreactor with designed scale of 1 000 m3/d is conducted combined with a demonstration project. The systematical researches on the efficiency of combined operation conditions of anaerobic-aerobic and anaerobic-aerobic-flocculation as well as chemical phosphorus removal of hypersaline mustard wastewater are conducted. The optimal operation condition and parameters in pretreatment of mustard wastewater in winter （the water temperature ranges 8-15 ~C） are determined： the anaerobic load is 3.0 kg （COD）/（m3.d）, the average COD and phosphate concentration of the inflow are respectively 3 883 mg/L and 35.53 mg/L and the dosage of flocculent （PAC） is 400 mg/L. The anaerobic-aerobic-flocculation combined operation condition and postpositive phosphorous removal with ferrous sulfate are employed. After treatment, the COD of the effluent is 470 mg/L and the average phosphate concentration is 5.09 mg/L. The effluent could achieve the third-level of Integrated Wastewater Discharge Standard （GB 8978--1996）.展开更多
The mechanism of removing phosphate by MSWI(municipal solid waste incineration)fly ash was investigated by SEM(scanning electron microscopy)with EDS(energy dispersion spectrum),XRD(X-ray diffraction),FT-IR(Fourier tra...The mechanism of removing phosphate by MSWI(municipal solid waste incineration)fly ash was investigated by SEM(scanning electron microscopy)with EDS(energy dispersion spectrum),XRD(X-ray diffraction),FT-IR(Fourier transform infrared spectroscopy),BET(specific surface area),and BJH(pore size distribution).The results indicate that the removal rate of phosphate(100 mg/L)in 50 mL phosphorus wastewater reaches at 99.9% as the dosage of MSWI fly ash being 0.9000 g under room temperature.The specific surface area of MSWI fly ash is less than 6.1 m2/g and the total pore volume is below 0.021 cm3/g,suggesting that the absorption capacity of calcite is too weak to play an important role in phosphate removal.SEM images show that drastic changes had taken place on its specific surface shape after reaction,and EDS tests indicate that some phosphate precipitates are formed and attached onto MSWI fly ash particles.Chemical precipitation is the main manner of phosphate removal and the main reaction is: 3Ca2++2 PO4 3-+xH2O→Ca3(PO4)2↓·xH2O.Besides,XRD tests show that the composition of MSWI fly ash is complex,but CaSO4 is likely to be the main source of Ca2+.The soluble heavy metals in MSWI fly ash are stabilized by phosphate.展开更多
To degrade the organic compounds in the electroplating wastewater,magnetic field was tentatively introduced into electrocatalytic oxidation on Ti-PbO2 anode.The magnetic field assisted electrocatalytic oxidation can p...To degrade the organic compounds in the electroplating wastewater,magnetic field was tentatively introduced into electrocatalytic oxidation on Ti-PbO2 anode.The magnetic field assisted electrocatalytic oxidation can promote anion movement and the generation of active species,resulting more organic compounds to be oxidized and degraded.Oxidation parameters such as treatment time,current density and initial pH of the wastewater were systematically discussed and optimized.The mineralization of organic compounds is improved by over 15% under a magnetic density of 22 mT while the current density is 50 A/m2,pH is 1.8 and the reaction time is 1.5 h.The results indicate that the magnetic field assisted electrocatalytic oxidation has considerable potential in electroplating wastewater treatment.展开更多
Decoloration and mineralization of yeast wastewater were investigated by using Ce-Fe/Al2O3 as a heterogeneous photo-Fenton catalyst in fluidized bed reactor in order to solve the problem of yeast wastewater discharge....Decoloration and mineralization of yeast wastewater were investigated by using Ce-Fe/Al2O3 as a heterogeneous photo-Fenton catalyst in fluidized bed reactor in order to solve the problem of yeast wastewater discharge. The experimental results were assessed in terms of total organic carbon（TOC） reduction. The operational and reaction conditions affecting the efficiencies of TOC removal such as initial pH value, H2O2 concentration, catalyst loading and UV power were studied. The results show that TOC is reduced from 347.6 mg/L to 10.8 mg/L, color is changed from 500 units to 0 under the conditions as follows： initial pH value 6. 0, H2O2 concentration of 1. 000 g/L, catalyst loading of 5 g/L, reaction duration of 120 rain and reaction temperature of 30 ℃. The irradiated Ce-Fe/Al2O3 catalyst was complexed with 1,10-phenanthroline and then it was subjected to Fourier transform infrared spectroscopy and diffuse reflectance spectroscopy to confirm the formation of Fe（Ⅱ） in the solid state. Heterogeneous photo-Fenton reaction proves to be effective for the treatment of yeast wastewater.展开更多
The removal of oil from oily wastewater in thermal power plant by coal fly ash(CFA) was investigated. It contained about 2.5 g/L of mineral oil,which had to be treated efficiently before it was discharged. The experim...The removal of oil from oily wastewater in thermal power plant by coal fly ash(CFA) was investigated. It contained about 2.5 g/L of mineral oil,which had to be treated efficiently before it was discharged. The experiments were carried out as a function of different initial concentrations of oil,mass dosage,contact time and pH value to obtain the optimum conditions for the removal of oil from oily wastewater. The experimental results show that CFA presents the most suitable conditions for the removal of oil from waste-water at a dosage of CFA 2.5 g/L,15 min of contact time and a pH value of 4.8. The adsorption process is performed with almost 96% of oil removal from wastewater. The kinetic data meet the second-order kinetic model. The Langmuir and Freundlich adsorption models were applied to describing the experimental isotherms and isotherm constants. The equilibrium data fit very well with the Freundlich model.展开更多
At present,as the majority of nursing homes, resorts,villages,villas and other decentralized living areas are far away from municipal sewer system,it is difficult to transport municipal waste water to city sewage trea...At present,as the majority of nursing homes, resorts,villages,villas and other decentralized living areas are far away from municipal sewer system,it is difficult to transport municipal waste water to city sewage treatment plants for processing.If the large quantity of decentralized wastewater were directly discharged to the rivers,lakes or other receiving water body without treatment,seriously contaminate to surface water and groundwater occurred.According to the analysis on characteristics of distributed展开更多
Ammonia is the major pollutant in many industrial and agricultural wastewaters,while with an increasing demand for nitrogen fertilizer worldwide,recovery of ammonia from high concentration ammonium wastewater is a sig...Ammonia is the major pollutant in many industrial and agricultural wastewaters,while with an increasing demand for nitrogen fertilizer worldwide,recovery of ammonia from high concentration ammonium wastewater is a significant way to reduce environmental pollution and to meet the development requirements.The present work was to investigate the factors following pH value,molar ratio of chemical reagents to afford theoretical support for wastewater treatment and resource recycling.Precipitate of struvite was analyzed by X-ray diffraction(XRD).Results indicated that by formation of magnesium ammoniumphosphate,ammonium in steel wastewater could be removed under the conditions following pH 10,with molar ratio of PO43-∶NH4+∶Mg2+ 1.3∶1∶1.2,and the ammonium removal efficiency was up to 95%.展开更多
A bacterium strain HS-03 was isolated from the activated sludge plant in a suburb of Wuhan city, China which has been found to be capable of aerobic denitrification. The effect of different inoculated amounts of pre-c...A bacterium strain HS-03 was isolated from the activated sludge plant in a suburb of Wuhan city, China which has been found to be capable of aerobic denitrification. The effect of different inoculated amounts of pre-cultured media was analyzed. The denitrifying rates of this strain under aerobic and micro-anaerobic conditions were compared. The result indicated that the rate was almost not affected by the presence of oxygen. 10m M nitrate was removed more than 90% in 36 hours by this bacterium in the specific medium. During the denitrifying process, nitrite was always kept at very low level. The denitrification potential of this bacterium was evaluated to treat artificial wastewater under fully aerobic conditions. Main biochemical and physiological features of this strain were characterized. The 16S rDNA sequence was compared with the published data in GenBank by using BLAST. The BLAST level of similarity to Pseudomonas stutzeri was 99.1%. These results of phenotype and genotype proved that the strain HS-03 was a new strain belonging to the species of P. stutzeri.展开更多
In order to design the technological process of desalination by electrodialysis for the industrial wastewater of an alumina plant, the limit current density of the industrial wastewater is measured, and the equations ...In order to design the technological process of desalination by electrodialysis for the industrial wastewater of an alumina plant, the limit current density of the industrial wastewater is measured, and the equations of limit current density, voltage drop of the unit membrane pair at the limiting current and desalination ratio at the limiting current were obtained.展开更多
基金Xiong′an New Area Science and Technology Innovation Project(2022XACX1000)。
文摘[Background]The previous studies suggest that radioactive elements like Cs and Sr may adversely affect marine ecosystems and the fishing industry.Traditional treatment systems for radioactive wastewater like the Advanced Liquid Processing System(ALPS)and Kurion have faced challenges in limiting concentration and achieving safety criteria.Studies suggest potential long-term impacts on benthic organisms and seafood networks due to radioactive elements like Cs and Sr from the discharged radioactive wastewater,which may hinder post-disaster recovery and provoke economic losses in the fishing industry both domestically and internationally.A series of studies indicate that there are issues of Cs and Sr pollution migration in soil and water conservation in Fukushima.[Methods]To provide feasible solutions,the main article includes five nuclear wastewater treatment technologies,and soil and water conservation measures for different media(water and soil)were evaluated through reviewing the previous fifteen years'articles.To provide feasible solutions,the main articles,the phytoextraction technologies in Cs and Sr treatment within different land use areas were wildly analyzed(Camellia japonica,Arabidopsis halleri and other local species).[Results]1)A 99.9%removal rate for Cs^(+)and 99.5%for Sr^(2+)was achieved by the KFe[Fe(CN)_(6)]and BaSO_(4)co-precipitation method.2)For membrane filtration,Sr^(2+)and Cs^(+)were removed using metal-organic framework(MOF/graphene oxide)and ion exchange techniques using inorganic materials like titanosilicates.The absorption efficiency of membrane filtration for Sr^(2+)and Cs^(+)was at least 92%and 94%,respectively.The study analyzed soil and water conservation technologies in different land uses,river basins and catchments.3)The underground water treatment mainly were completed via the membrance technologies like reverse osmosis and Permeable Reactive Barriers(PRB)technologies.The ^(90) Sr concentration decreased 77%-91%compared to the initial concentration by PRB technology.These diverse methods offered effective strategies for radioactive wastewater treatment,especially the co-precipitation method may be feasible remediation measures to ensure ecological safety surrounding nuclear power utilizing areas.Soil and water conservation measures for soil pollution treatment mainly focused on the use of stabilizers to hinder the migration of Cs and Sr in the soil and the effects of wind erosion such as interpolyelectrolyte complexes.[Conclusions]We evaluated the pollution of Cs and Sr in the Fukushima nuclear radiation soil and water to provide solutions for the treatment of nuclear wastewater and to prevent radionuclide pollutants from migrating into the soil and water.
文摘The experimental results of producing deionized water for the themoelectric factory from two types of the industrial wastewater of an alumina plant by using membrane technology are reported in this paper. For the treatment of the industrial wastewater with high salinity and pH value, the combination of electrodialysis (ED) and reverse osmosis (RO) is utilized, while for the treatment of the low salinity wastewater with low pH value, RO is directly used. The research results show that the above mentioned methods are effective. The technological process of the wastewater treatment with the capacity of 120 tons is designed on the basis of the experimental results.
基金Projects(2009GG10005004, 2010GHY10504) supported by the Scientific and Technological Foundation of Shandong Province,ChinaProject(2011GHY11531) supported by the Science and Technology Development Program of Shandong Province,ChinaProject(ZR2009BM015) supported by the Natural Science Foundation of Shandong Province,China
文摘A coupled system consisting of an upflow membrane-less microbial fuel cell (upflow ML-MFC) and a photobioreactor was developed, and its effectiveness for continuous wastewater treatment and electricity production was evaluated. Wastewater was fed to the upflow ML-MFC to remove chemical oxygen demand (COD), phosphorus and nitrogen with simultaneous electricity generation. The effluent from the cathode compartment of the upflow ML-MFC was then continuously fed to an external photobioreactor for removing the remaining phosphorus and nitrogen using microalgae. Alone, the upflow ML-MFC produces a maximum power density of 481 mW/m 3 , and obtains 77.9% COD, 23.5% total phosphorus (TP) and 97.6% NH4+-N removals. When combined with the photobioreactor, the system achieves 99.3% TP and 99.0% NH4+-N total removal. These results show both the effectiveness and the potential application of the coupled system to continuously treat domestic wastewater and simultaneously generate electricity and biomass.
基金Project(201209013)supported by Special Fund for Environmental Scientific Research in the Public Interest,China
文摘A laboratory scale up-flow biological activated carbon(BAC) reactor was constructed for the advanced treatment of synthetic flotation wastewater. Biodegradation of a common collector(i.e., ethyl xanthate) for non-ferrous metallic ore flotation was evaluated. The results show that the two stages of domestication can improve microbial degradation ability. The BAC reactor obtains a chemical oxygen demand(COD) reduction rate of 82.5% for ethyl xanthate and its effluent COD concentration lowers to below 20 mg/L. The kinetics equation of the BAC reactor proves that the activated carbon layers at the height of 0 mm to 70 mm play a key role in the removal of flotation reagents. Ultraviolet spectral analysis indicates that most of the ethyl xanthate are degraded by microorganisms after advanced treatment by the BAC reactor.
基金Project(20113282241450) supported by the Science and Technology Program from Ministry of Transport of China
文摘The electrochemical treatment of wastewater containing chlorophenols （2-monochlorophenol, 4-monochlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol） was carried out experimentally with synthetic boron-d0ped diamond （BDD） thin film electrodes. Current vs time curves under different cell voltages were measured. Removal rate of COD, instant current efficiency （ICE） and energy consumption were investigated under different current densities. The influence of supporting media is reported, which plays an important role in determining the global oxidation rate. The oxidative chloride is stronger than peroxodisulphate. The electrochemical characteristics of boron-doped diamond electrodes were investigated in comparison with active coating Ti substrate anode （ACT）. The experimental results show that BDD is markedly superior to ACT due to its different absorption properties.
基金Project(2006BAJ04A)suppprted by the National Sci-Tech Support Plan,China
文摘Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment of biologically pretreated coking wastewater. Particular attention was paid to the performance of the integrated system for the removal of chemical oxygen demand(COD), ammonia nitrogen(NH3-N) and total nitrogen(TN). The average removal efficiencies of COD, NH3-N and TN were 76.28%, 96.76% and 59.97%, with the average effluent mass concentrations of 56, 0.53 and 18.83 mg/L, respectively, reaching the first grade of the national discharge standard. Moreover, the results of gas chromatography/mass spectrum(GC/MS) and gel permeation chromatography(GPC) analysis demonstrated that the refractory organic compounds with high relative molecular mass were partly removed in IZVI process by the function of oxidation-reduction, flocculation and adsorption which could also enhance the biodegradability of the system effluent. The removal efficiencies of NH3-N and TN were achieved mainly in the subsequent AF/BAF reactors by nitrification and denitrification. Overall, the results obtained show that the application of IZVI in combination with AF/BAF is a promising technology for advanced treatment of biologically pretreated coking wastewater.
基金Projects(ZR2013BL010,ZR2012DL05)supported by the Natural Science Foundation of Shandong Province,ChinaProject(4041412016)supported by the Research Excellence Award of Shandong University of Technology,ChinaProjects(2013GG03116,2011GG02115)supported by the Science and Technology Development Planning Project of Zibo,China
文摘High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synthetic high salinity wastewater was evaluated at laboratory scale during a 110-day operation.The reactor was operated in a 12 h cycle,and each cycle consisted of 0.25 h influent addition,8 h aeration,3 h anoxic reaction,0.5 h sedimentation and 0.25 h effluent withdrawal.Gradual increase in salinity gradient was applied during the acclimatization period.The acclimated SBBR system was demonstrated to be an effective process to remove organic compounds and ammonia nitrogen under high salinity conditions with chemical oxygen demand(COD)and ammonia nitrogen(NH3-N)removal efficiencies of 88% and 80%,respectively.The microscopic examination indicated that rather than rotifers or vorticella,the zoogloea,filamentous fungus mingled with a small quantity of swimming infusorians were dominant bacteria in SBBR system.The removal efficiencies close to 80% in COD and 75% in NH3-N were achieved at an organic loading rate(OLR)of 0.96 kg COD/(m3·d),pH of 7.0,salinity of 14 g/L and NH3-N of 30 mg/L.
文摘The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6. Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu to As was 2：1 and pH value of the neutralized wastewater was adjusted to 8.0 by sodium hydroxide. The arsenious acid solution and red residue were produced after copper arsenite mixed with water according to the ratio of liquid to solid of 4：1 and copper arsenite was reduced by SO2 at 60℃ for 1 h. The white powder was gained after the arsenious acid solution was evaporated and cooled. Copper sulfate solution was obtained after the red residue was leached by H2SO4 solution under the action of air. The results show that red residue is Cu3（SO3）2·2H2O and the white powder is As2O3. The leaching rate of Cu reaches 99.00% when the leaching time is 1.5 h, molar ratio of H2SO4 to Cu is 1.70, H2SO4 concentration is 24% and the leaching temperature is 80 ℃. The direct recovery rate of copper sulfate is 79.11% and the content of CuSOa·5H2O is up to 98.33% in the product after evaporating and cooling the copper sulfate solution.
基金Project(BE2015628)supported by Jiangsu Province Science and Technology Support Program,China
文摘Considering that Fe,Al elements in bauxite residue are active components for water purification,an effective polyaluminum ferric chloride(PAFC)coagulant derived from bauxite residue,with Fe2O3 content>5.1%,Al2O3%>6.5%,basicity>65%,was successfully prepared.The effect of as-prepared PAFC on the zeta potential for printing and dyeing wastewater was investigated.Comparing with polyferric chloride(PFC)and polyferric sulfate(PFS)for printing and dyeing wastewater treatment,prepared bauxite residue-based PAFC exhibited the optimal performance in the aspects of chromaticity and chemical oxygen demand(COD)removal rate.Furthermore,the combination of bauxite residue-based PAFC and PFS for synergy coagulation of such wastewater demonstrated an obvious positive effect.With the proportion between as-prepared PAFC and PFS to be 2.5:1,the COD of treated wastewater could be further reduced to meet the national level A standard of China,providing a promising route to solve the problem of substandard printing and dyeing sewage outfall by a simple coagulation strategy.
基金Project(20090191120036) supported by the Fund of Doctoral Program of Ministry of Education,China
文摘A full-scale experimental study of treating mustard wastewater by the integrated bioreactor with designed scale of 1 000 m3/d is conducted combined with a demonstration project. The systematical researches on the efficiency of combined operation conditions of anaerobic-aerobic and anaerobic-aerobic-flocculation as well as chemical phosphorus removal of hypersaline mustard wastewater are conducted. The optimal operation condition and parameters in pretreatment of mustard wastewater in winter （the water temperature ranges 8-15 ~C） are determined： the anaerobic load is 3.0 kg （COD）/（m3.d）, the average COD and phosphate concentration of the inflow are respectively 3 883 mg/L and 35.53 mg/L and the dosage of flocculent （PAC） is 400 mg/L. The anaerobic-aerobic-flocculation combined operation condition and postpositive phosphorous removal with ferrous sulfate are employed. After treatment, the COD of the effluent is 470 mg/L and the average phosphate concentration is 5.09 mg/L. The effluent could achieve the third-level of Integrated Wastewater Discharge Standard （GB 8978--1996）.
基金Projects(51108100,50808184)supported by the National Natural Science Foundation of ChinaProject(100Z007)supported by the Ministry of Education of China+1 种基金Project(200103YB020)supported by Foundation of Guangxi Educational Committee,ChinaProject supported by Guangxi Normal University Education Development Foundation for Young Scholars,China
文摘The mechanism of removing phosphate by MSWI(municipal solid waste incineration)fly ash was investigated by SEM(scanning electron microscopy)with EDS(energy dispersion spectrum),XRD(X-ray diffraction),FT-IR(Fourier transform infrared spectroscopy),BET(specific surface area),and BJH(pore size distribution).The results indicate that the removal rate of phosphate(100 mg/L)in 50 mL phosphorus wastewater reaches at 99.9% as the dosage of MSWI fly ash being 0.9000 g under room temperature.The specific surface area of MSWI fly ash is less than 6.1 m2/g and the total pore volume is below 0.021 cm3/g,suggesting that the absorption capacity of calcite is too weak to play an important role in phosphate removal.SEM images show that drastic changes had taken place on its specific surface shape after reaction,and EDS tests indicate that some phosphate precipitates are formed and attached onto MSWI fly ash particles.Chemical precipitation is the main manner of phosphate removal and the main reaction is: 3Ca2++2 PO4 3-+xH2O→Ca3(PO4)2↓·xH2O.Besides,XRD tests show that the composition of MSWI fly ash is complex,but CaSO4 is likely to be the main source of Ca2+.The soluble heavy metals in MSWI fly ash are stabilized by phosphate.
基金Project(2008ZX07101-006-09) supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China
文摘To degrade the organic compounds in the electroplating wastewater,magnetic field was tentatively introduced into electrocatalytic oxidation on Ti-PbO2 anode.The magnetic field assisted electrocatalytic oxidation can promote anion movement and the generation of active species,resulting more organic compounds to be oxidized and degraded.Oxidation parameters such as treatment time,current density and initial pH of the wastewater were systematically discussed and optimized.The mineralization of organic compounds is improved by over 15% under a magnetic density of 22 mT while the current density is 50 A/m2,pH is 1.8 and the reaction time is 1.5 h.The results indicate that the magnetic field assisted electrocatalytic oxidation has considerable potential in electroplating wastewater treatment.
基金Project(20277010) supported by the National Natural Science Foundation of China
文摘Decoloration and mineralization of yeast wastewater were investigated by using Ce-Fe/Al2O3 as a heterogeneous photo-Fenton catalyst in fluidized bed reactor in order to solve the problem of yeast wastewater discharge. The experimental results were assessed in terms of total organic carbon（TOC） reduction. The operational and reaction conditions affecting the efficiencies of TOC removal such as initial pH value, H2O2 concentration, catalyst loading and UV power were studied. The results show that TOC is reduced from 347.6 mg/L to 10.8 mg/L, color is changed from 500 units to 0 under the conditions as follows： initial pH value 6. 0, H2O2 concentration of 1. 000 g/L, catalyst loading of 5 g/L, reaction duration of 120 rain and reaction temperature of 30 ℃. The irradiated Ce-Fe/Al2O3 catalyst was complexed with 1,10-phenanthroline and then it was subjected to Fourier transform infrared spectroscopy and diffuse reflectance spectroscopy to confirm the formation of Fe（Ⅱ） in the solid state. Heterogeneous photo-Fenton reaction proves to be effective for the treatment of yeast wastewater.
基金Project(2007BAC24B02) supported by the National Science & Technology Pillar Program during the 11th Five-Year Plan Period,ChinaProject(20070420713) supported by China Postdoctoral Science FoundationProject(CSTC2007AD7036) supported by Chongqing Key Tackle Research Project,China
文摘The removal of oil from oily wastewater in thermal power plant by coal fly ash(CFA) was investigated. It contained about 2.5 g/L of mineral oil,which had to be treated efficiently before it was discharged. The experiments were carried out as a function of different initial concentrations of oil,mass dosage,contact time and pH value to obtain the optimum conditions for the removal of oil from oily wastewater. The experimental results show that CFA presents the most suitable conditions for the removal of oil from waste-water at a dosage of CFA 2.5 g/L,15 min of contact time and a pH value of 4.8. The adsorption process is performed with almost 96% of oil removal from wastewater. The kinetic data meet the second-order kinetic model. The Langmuir and Freundlich adsorption models were applied to describing the experimental isotherms and isotherm constants. The equilibrium data fit very well with the Freundlich model.
文摘At present,as the majority of nursing homes, resorts,villages,villas and other decentralized living areas are far away from municipal sewer system,it is difficult to transport municipal waste water to city sewage treatment plants for processing.If the large quantity of decentralized wastewater were directly discharged to the rivers,lakes or other receiving water body without treatment,seriously contaminate to surface water and groundwater occurred.According to the analysis on characteristics of distributed
基金supported by the National High Technology Research and Development Program of China(2008AA031202)Major Science&Technology of Chongqing(CSTC2009AB4162)+2 种基金Major National S&TProgram(2008ZX07315-003)Natural Science Foundation of China(20806095)China Postdoctor Foundation(20080430747)
文摘Ammonia is the major pollutant in many industrial and agricultural wastewaters,while with an increasing demand for nitrogen fertilizer worldwide,recovery of ammonia from high concentration ammonium wastewater is a significant way to reduce environmental pollution and to meet the development requirements.The present work was to investigate the factors following pH value,molar ratio of chemical reagents to afford theoretical support for wastewater treatment and resource recycling.Precipitate of struvite was analyzed by X-ray diffraction(XRD).Results indicated that by formation of magnesium ammoniumphosphate,ammonium in steel wastewater could be removed under the conditions following pH 10,with molar ratio of PO43-∶NH4+∶Mg2+ 1.3∶1∶1.2,and the ammonium removal efficiency was up to 95%.
基金National Natural Science Foundation of China No.3017001
文摘A bacterium strain HS-03 was isolated from the activated sludge plant in a suburb of Wuhan city, China which has been found to be capable of aerobic denitrification. The effect of different inoculated amounts of pre-cultured media was analyzed. The denitrifying rates of this strain under aerobic and micro-anaerobic conditions were compared. The result indicated that the rate was almost not affected by the presence of oxygen. 10m M nitrate was removed more than 90% in 36 hours by this bacterium in the specific medium. During the denitrifying process, nitrite was always kept at very low level. The denitrification potential of this bacterium was evaluated to treat artificial wastewater under fully aerobic conditions. Main biochemical and physiological features of this strain were characterized. The 16S rDNA sequence was compared with the published data in GenBank by using BLAST. The BLAST level of similarity to Pseudomonas stutzeri was 99.1%. These results of phenotype and genotype proved that the strain HS-03 was a new strain belonging to the species of P. stutzeri.
文摘In order to design the technological process of desalination by electrodialysis for the industrial wastewater of an alumina plant, the limit current density of the industrial wastewater is measured, and the equations of limit current density, voltage drop of the unit membrane pair at the limiting current and desalination ratio at the limiting current were obtained.
