Instead of pure bacteria, induction mutation of activated sludge by ultraviolet (Uv) was studied and used to treat pulping wastewater by continuous- flow. The result showed the mutagenic activated sludge had remarkabl...Instead of pure bacteria, induction mutation of activated sludge by ultraviolet (Uv) was studied and used to treat pulping wastewater by continuous- flow. The result showed the mutagenic activated sludge had remarkable effect and application potential in pulping wastewater treatment. Comparing with common activated sludge, the mutagenic activated sludge was more suitable for lignose decomposition and had high decomposing efficiency.展开更多
The flucculation efficiency of compound bioflocculant produced by flocculant-producing bacteria was investigated in this study. Cheap cellulose was selected as the substrate for the production of a lower cost bioflocc...The flucculation efficiency of compound bioflocculant produced by flocculant-producing bacteria was investigated in this study. Cheap cellulose was selected as the substrate for the production of a lower cost bioflocculant. The end product of cellulose decomposing bacteria was utilized as substrate for flocculant-producing bacteria. The optimum fermentation conditions were determined as follows： the initial fermentation and fermentation time was 5 d and 1 d respectively, the temperature was 30 ℃, the rotation speed was 120 r/min, the amount of CaCl2 solution （ 10% ） was 1.5 ml/L. The flocculation test indicated that the bioflocculant had high efficiency in the removal of the turbldity raw water from Songhua River.展开更多
Natural assemblages of marine bacteria were chosen in a batch culture experiments. The impact of varying nitrogen substrate concentrations and the substrate C：N ratios （C：Ns） on the bacterial C：N ratio （C：NB）,...Natural assemblages of marine bacteria were chosen in a batch culture experiments. The impact of varying nitrogen substrate concentrations and the substrate C：N ratios （C：Ns） on the bacterial C：N ratio （C：NB）, the bacterial growth efficiency （BGE） and ammonium regeneration was mainly examined. The C：Ns ratios varied from 5：1 （carbon limitation） to 40：1 （nitrogen limitation） with varying combinations of glucose and NO3. The C：NB ratio had positive relationship with the C：Ns ratio （r=0.93, n=8）, whose value was 3.77 when the C：Ns ratio was 5：1 but increased to 6.47 when the C：Ns ratio was 40：1. These results indicate that the C：NB ratio is a potential diagnostic tool for determining the bacterial growth in natural waters controlled by either, carbon or nitrogen. BGE decreased with the declining nitrate concentration and negatively related to C：N8 （r=-0.51, n=8）. The average value of BGE was 0.20. This value was a little lower than other reports, which could be induced by the nitrogen source used in our experiments. Finally, regeneration time of ammonium delayed with the increasing C：Ns ratio, which indicates that there were different metabolism mechanisms when bacterial growth was limited by carbon source and nitrogen source.展开更多
Paper and pulp mill is a source of major pollution generating industry leaving huge amount of intensely colored effluent to the receiving end. Rapid increase of population and the increased demand for industrial estab...Paper and pulp mill is a source of major pollution generating industry leaving huge amount of intensely colored effluent to the receiving end. Rapid increase of population and the increased demand for industrial establishments to meet human needs have created problems such as over exploitation of available resources, increased pollution taking place on land, air and water environment. The intention of this research paper is to identify predominant bacteria and fungi in paper and pulp mill effluent in addition to evaluate the degradation efficiency of individual isolates and combination of isolates. Treatment efficiency of individual isolates and combination of isolates are evaluated by shake flask method. Combination of Pseudomonas Alkaligenes, Bacillus subtilis along with Trichoderma reesei shows higher BOD, COD reduction of 99% and 85% respectively. As individual isolates Pseudomonas Alkaligenes show 92% BOD reduction and 77% COD reduction over other bacterial isolates and Trichoderma reesei removed 99% BOD and 80% COD respectively.展开更多
In the present work, the treatment of synthetic waters doped with iron (II) has been studied. The treatment mechanism used in this study is the biological oxidation which consists, in test tubes, of bringing bacteria ...In the present work, the treatment of synthetic waters doped with iron (II) has been studied. The treatment mechanism used in this study is the biological oxidation which consists, in test tubes, of bringing bacteria isolated on Petri dishes into contact with water containing divalent iron (II). These de-ironing bacteria (non-specific bacteria) are used to carry out laboratory biological oxidation experiments on iron (II) under different pH conditions (pH = 3.4 - 3.6, pH = 7.3 - 7.5 and pH = 9.8 - 10) and variable concentration of iron (II). Biological treatment trials included different concentrations of iron during time intervals of a day. Examination of the elimination kinetics of Iron (II) indicates a removal rate of 59.453% for an initial iron concentration in the synthetic solution of 1 mg·L−1 at basic pH (pH = 9.8 - 10). Therefore, the degradation of divalent iron by this method seems to be quite effective, but it should be noted that biological nitrification is impaired by the presence of high iron concentrations above 5 mg·L−1.展开更多
文摘Instead of pure bacteria, induction mutation of activated sludge by ultraviolet (Uv) was studied and used to treat pulping wastewater by continuous- flow. The result showed the mutagenic activated sludge had remarkable effect and application potential in pulping wastewater treatment. Comparing with common activated sludge, the mutagenic activated sludge was more suitable for lignose decomposition and had high decomposing efficiency.
基金Sponsored by the Science Foundation of Heilongjiang Province(Grant No.GB02C202 -02).
文摘The flucculation efficiency of compound bioflocculant produced by flocculant-producing bacteria was investigated in this study. Cheap cellulose was selected as the substrate for the production of a lower cost bioflocculant. The end product of cellulose decomposing bacteria was utilized as substrate for flocculant-producing bacteria. The optimum fermentation conditions were determined as follows： the initial fermentation and fermentation time was 5 d and 1 d respectively, the temperature was 30 ℃, the rotation speed was 120 r/min, the amount of CaCl2 solution （ 10% ） was 1.5 ml/L. The flocculation test indicated that the bioflocculant had high efficiency in the removal of the turbldity raw water from Songhua River.
基金The Key Program of International Science and Technology Cooperation from the Ministry of Science and Technology of China under contract No.2004DFA03600the Plan of National Key Basic Research and Development Program Item of China under contract No.2001CB409703the Qingdao Natural Science Foundation of China under contract No. 04-2-JZ-88
文摘Natural assemblages of marine bacteria were chosen in a batch culture experiments. The impact of varying nitrogen substrate concentrations and the substrate C：N ratios （C：Ns） on the bacterial C：N ratio （C：NB）, the bacterial growth efficiency （BGE） and ammonium regeneration was mainly examined. The C：Ns ratios varied from 5：1 （carbon limitation） to 40：1 （nitrogen limitation） with varying combinations of glucose and NO3. The C：NB ratio had positive relationship with the C：Ns ratio （r=0.93, n=8）, whose value was 3.77 when the C：Ns ratio was 5：1 but increased to 6.47 when the C：Ns ratio was 40：1. These results indicate that the C：NB ratio is a potential diagnostic tool for determining the bacterial growth in natural waters controlled by either, carbon or nitrogen. BGE decreased with the declining nitrate concentration and negatively related to C：N8 （r=-0.51, n=8）. The average value of BGE was 0.20. This value was a little lower than other reports, which could be induced by the nitrogen source used in our experiments. Finally, regeneration time of ammonium delayed with the increasing C：Ns ratio, which indicates that there were different metabolism mechanisms when bacterial growth was limited by carbon source and nitrogen source.
文摘Paper and pulp mill is a source of major pollution generating industry leaving huge amount of intensely colored effluent to the receiving end. Rapid increase of population and the increased demand for industrial establishments to meet human needs have created problems such as over exploitation of available resources, increased pollution taking place on land, air and water environment. The intention of this research paper is to identify predominant bacteria and fungi in paper and pulp mill effluent in addition to evaluate the degradation efficiency of individual isolates and combination of isolates. Treatment efficiency of individual isolates and combination of isolates are evaluated by shake flask method. Combination of Pseudomonas Alkaligenes, Bacillus subtilis along with Trichoderma reesei shows higher BOD, COD reduction of 99% and 85% respectively. As individual isolates Pseudomonas Alkaligenes show 92% BOD reduction and 77% COD reduction over other bacterial isolates and Trichoderma reesei removed 99% BOD and 80% COD respectively.
文摘In the present work, the treatment of synthetic waters doped with iron (II) has been studied. The treatment mechanism used in this study is the biological oxidation which consists, in test tubes, of bringing bacteria isolated on Petri dishes into contact with water containing divalent iron (II). These de-ironing bacteria (non-specific bacteria) are used to carry out laboratory biological oxidation experiments on iron (II) under different pH conditions (pH = 3.4 - 3.6, pH = 7.3 - 7.5 and pH = 9.8 - 10) and variable concentration of iron (II). Biological treatment trials included different concentrations of iron during time intervals of a day. Examination of the elimination kinetics of Iron (II) indicates a removal rate of 59.453% for an initial iron concentration in the synthetic solution of 1 mg·L−1 at basic pH (pH = 9.8 - 10). Therefore, the degradation of divalent iron by this method seems to be quite effective, but it should be noted that biological nitrification is impaired by the presence of high iron concentrations above 5 mg·L−1.
