Experiment on microbial degradation with two kinds of biological process, hydrolytic acidification-aerobic process and aerobic process was conducted to treat the anthraquinone dye wastewater with COD Cr concentration ...Experiment on microbial degradation with two kinds of biological process, hydrolytic acidification-aerobic process and aerobic process was conducted to treat the anthraquinone dye wastewater with COD Cr concentration of 400 mg/L and chroma 800. The experimental result demonstrated that the hydrolytic-aerobic process could raise the biodegradability of anthraquinone dye wastewater effectively. The effluent COD Cr can reach 120170 mg/L and chroma 150 which is superior to that from simple aerobic process.展开更多
An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic ac...An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic activated sludge were used as the biocatalyst and artificial wastewater was tested as substrate. During the electrochemically active microbe enrichment stage, a stable power output of 536 mW.m-3 with reference to the anode volume was generated by the ML-MFC running in batch mode. The voltage output decreased from 203 mV to about 190 mV after the ML-MFC was changed from batch mode to normally continuous mode, indicating that planktonic electrochemically active bacterial strains in the ML-MFC may be carried away along with the effluent. Cyclic voltammograms showed that the attached microbes possessed higher bioelectrochemical activity than the planktonic microbes. Forced aeration to the cathode benefited the electricity generation obviously. Higher feeding rate and longer electrode distance both increased the electricity generation. The coulombic yield was not more than 20% throughout the study, which is lower than that of MFCs with membrane. It is proposed that dissolved oxygen diffused from the cathode to the anode may consume part of the substrate.展开更多
The effects of feed temperature and pH value on the removal of aqueous phenol wastewater by vacuum membrane distillation process are studied by experiments employing micro porous membranes of poly vinylidene fluoride ...The effects of feed temperature and pH value on the removal of aqueous phenol wastewater by vacuum membrane distillation process are studied by experiments employing micro porous membranes of poly vinylidene fluoride (PVDF) and ploy tetrafluoro ethylene (PTFE) with nominal average pore sizes 0.22 mm and 0.20 mm, respectively. It is found that the optimal feed temperature for PVDF membrane is 50 ℃; and for PTFE membrane, 60 ℃. The pH value of the feed has little influence on the membrane fluxes and ion rejection ratios, while it influenced considerably on the selectivity. Increase of pH value of the feed is conducive to the increase of selectivity. In the same experimental conditions, PTFE membrane shows better separation performance than PVDF membrane does.展开更多
A laboratory experiment was undertaken in Soil Science Division of BRRI （Bangladesh Rice Research Institute） during 2010 to assess the quality of industrial effluents and city waste as a source of irrigation water f...A laboratory experiment was undertaken in Soil Science Division of BRRI （Bangladesh Rice Research Institute） during 2010 to assess the quality of industrial effluents and city waste as a source of irrigation water for agriculture. The treatments of the studies were the effluents of five different industrial sources like polyvinyl, dyeing, pharmaceuticals, beverage, tannery, mixed waste water （contaminated with effluents from many industries）, CWW （city waste water） and underground water as control. The industrial effluents, MWW （mixed waste water）, CWW and control water were tested for electrical conductivity, pH, and soluble ions such as Na^＋, Ca^2＋, Mg^2＋, K^＋, HCO3-, CO3^2-, NH4^＋-N and H2PO4^-. Micronutrients （Fe, Mn, Cu and Zn） and heavy metals （As, Pb, Cd, Cr and Ni） were analyzed from the samples. Beverage industry effluent showed acidic reaction, while the other industrial effluents showed alkaline reaction （pH 7.25-9.07）. Pharmaceutical, dyeing and tannery effluents showed EC of 3.40, 4.30 and 9.49 dS m^-1, respectively, compared to 0.54 dSm^-1 of the control. All the effluents except polyvinyl and beverage effluents and CWW recorded higher carbonate and bicarbonate content than that of control. Industrial effluents and CWW were higher in micronutrient content as compared to control. Dyeing, pharmaceutical and tannery effluents contained 2.51, 3.94 and 4.29 mg L^-1 lead, 0.15, 0.14 and 0.38 mg L^-1 chromium and 0.25, 0.24 and 0.16 mg L^-1 nickel, respectively which might be concemed for health hazard through food chain.展开更多
文摘Experiment on microbial degradation with two kinds of biological process, hydrolytic acidification-aerobic process and aerobic process was conducted to treat the anthraquinone dye wastewater with COD Cr concentration of 400 mg/L and chroma 800. The experimental result demonstrated that the hydrolytic-aerobic process could raise the biodegradability of anthraquinone dye wastewater effectively. The effluent COD Cr can reach 120170 mg/L and chroma 150 which is superior to that from simple aerobic process.
基金Supported by the National Natural Science Foundation of China （20306029, 20576137）.
文摘An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic activated sludge were used as the biocatalyst and artificial wastewater was tested as substrate. During the electrochemically active microbe enrichment stage, a stable power output of 536 mW.m-3 with reference to the anode volume was generated by the ML-MFC running in batch mode. The voltage output decreased from 203 mV to about 190 mV after the ML-MFC was changed from batch mode to normally continuous mode, indicating that planktonic electrochemically active bacterial strains in the ML-MFC may be carried away along with the effluent. Cyclic voltammograms showed that the attached microbes possessed higher bioelectrochemical activity than the planktonic microbes. Forced aeration to the cathode benefited the electricity generation obviously. Higher feeding rate and longer electrode distance both increased the electricity generation. The coulombic yield was not more than 20% throughout the study, which is lower than that of MFCs with membrane. It is proposed that dissolved oxygen diffused from the cathode to the anode may consume part of the substrate.
文摘The effects of feed temperature and pH value on the removal of aqueous phenol wastewater by vacuum membrane distillation process are studied by experiments employing micro porous membranes of poly vinylidene fluoride (PVDF) and ploy tetrafluoro ethylene (PTFE) with nominal average pore sizes 0.22 mm and 0.20 mm, respectively. It is found that the optimal feed temperature for PVDF membrane is 50 ℃; and for PTFE membrane, 60 ℃. The pH value of the feed has little influence on the membrane fluxes and ion rejection ratios, while it influenced considerably on the selectivity. Increase of pH value of the feed is conducive to the increase of selectivity. In the same experimental conditions, PTFE membrane shows better separation performance than PVDF membrane does.
文摘A laboratory experiment was undertaken in Soil Science Division of BRRI （Bangladesh Rice Research Institute） during 2010 to assess the quality of industrial effluents and city waste as a source of irrigation water for agriculture. The treatments of the studies were the effluents of five different industrial sources like polyvinyl, dyeing, pharmaceuticals, beverage, tannery, mixed waste water （contaminated with effluents from many industries）, CWW （city waste water） and underground water as control. The industrial effluents, MWW （mixed waste water）, CWW and control water were tested for electrical conductivity, pH, and soluble ions such as Na^＋, Ca^2＋, Mg^2＋, K^＋, HCO3-, CO3^2-, NH4^＋-N and H2PO4^-. Micronutrients （Fe, Mn, Cu and Zn） and heavy metals （As, Pb, Cd, Cr and Ni） were analyzed from the samples. Beverage industry effluent showed acidic reaction, while the other industrial effluents showed alkaline reaction （pH 7.25-9.07）. Pharmaceutical, dyeing and tannery effluents showed EC of 3.40, 4.30 and 9.49 dS m^-1, respectively, compared to 0.54 dSm^-1 of the control. All the effluents except polyvinyl and beverage effluents and CWW recorded higher carbonate and bicarbonate content than that of control. Industrial effluents and CWW were higher in micronutrient content as compared to control. Dyeing, pharmaceutical and tannery effluents contained 2.51, 3.94 and 4.29 mg L^-1 lead, 0.15, 0.14 and 0.38 mg L^-1 chromium and 0.25, 0.24 and 0.16 mg L^-1 nickel, respectively which might be concemed for health hazard through food chain.
