| With the development of modern industry, heavy metal pollution of soil has become the increasing environmental problems, which threatens the growth of living creatures, human health and the ecological environment. There are so many researches at home and abroad on the remediation of heavy metal polluted soil, the effect of which is not obvious and the traditional remediation of heavy metal polluted soil can’t meet the demand because of many limitations. In recent years, the microbiological remediation technology of heavy metals polluted soil has become a new field of study with wide public concern because of its high efficiency and no-secondary-pollution.In the early of this project, the related phytoremediation technology researches on heavy metal polluted soil in Hydro-Fluctuation Belt have been done and certain progress has been made. In this study based on the previous basis, the soil sample of Yunyang of Hydro-Fluctuation Belt of Three Gores Reservoir, which has better effect of phytoremediation. Five bacterial strains, which can remove C u, Zn and Cd, have been chosen: B01 is the bacterial strain with the removal of C u2+, B02, B03 are the bacterial strains with the removal of Cd2+, B04, B05 are the bacterial strains with the removal of Zn2+ strain. After cultivation, enrichment and purification, the preliminary identification results are as follows: B01, B02, B04 are Alcaligenes, B03 is Xanthomonas, B05 is Pseudomonas sp.In the experiment, under different p H, temperature and initial concentration of metal ions, the removal effects of C u2+、Cd2+、Zn2+ are observed according to the change of single factor with different nutrient solution. Among them, strain B01 removes C u2+, strain B02 and B03 removes Cd2+, and strain B04 and B05 removes Zn2+. The experimental results are as follows:Strains of B01 removal Cu2+ experiment, the heavy metal removal rate and the change of p H, the temperature curve respectively first rises after the fall, and negatively correlated with the change of the initial concentration of the C u2+; C u2+ removal and the change of the initial concentration of the Cu2+ decreased after the first rise; When p H 7, the removal of Cu2+ peak at 70%; When the temperature of 30℃, the removal of C u2+ peak at 70% when the initial concentration of 100 mg/L, the removal of C u2+ peak, of 70mg/L.Strains of B01 for copper removal effect in 30 ~ 100 mg/L C u2+ concentration meet zero- order of kinetics equation.Strain B02, B03, remove the experiment of Cd2+, heavy metal removal rate and the change of p H, temperature c urve respectively first rise after the fall, and negatively correlated with the change of the initial concentration of Cd2+; Cd2+ removal and the change curve of the initial concentration of the Cd2+ first rise after falling; When p H 7, strain B02, B03 of Cd2+ reach high removal rate, 66%, 42% respectively; Temperature of 30℃, strain B02, B03 of Cd2+ reach high removal rate, 66%, 42% respectively;Cd2+ when the initial concentration of 70 mg/L, strain B02, B03 of Cd2+ reach high removal, 49mg/L,40.6mg/L respectively. Strains of B02, B03 effect on removal of cadmium in 30 ~ 70 mg/L when the concentration of Cd2+ meets zero- order kinetics equation.Strain B04, B05, remove the experiment of Zn2+, heavy metal removal rate and the change of p H, temperature curve respectively first rise after the fall, and negatively correlated with the change of the initial concentration of the Zn2+. Zn2+ removal and the change of the initial concentration of the Zn2+ decreased after the first rise; When p H 7, strain B04, B05 of Zn2+ reach high removal rate, 68%, 65% respectively; Temperature of 30℃, strain B04, B05 of Zn2+ reach high removal rate, 63%, 58% respectively; Zn2+ when the initial concentration of 150 mg/L, strain B04, B05 of Zn2+ reach high removal, 67.5mg/L, 61.5mg/Lrespectively. Strains B04, B05 effect on removal of cadmium in 10 ~ 200 mg/L and 10 ~ 150 mg/L Zn2+ concentration zero order kinetics equation. |
PDF Full Text Request