| The development of advanced, economical and effective BFGD has become a hotspot on the study of flue gas desulfurization, as the result of progress of biology catalyzing. Bio-trickling flue gas desulfurization, a new technique, constructed on the basic of immobilized Thiobacillus ferrooxidans and the compound system of irons, is combined with inorganic chemistry and microbiology principles, which has many advantages of low cost, few energy sources needed, little secondary pollution and high efficiency. The paper has respectively studied factors influencing growth condition of free-bacterium, immobilization process of Thiobacillus ferrooxidans, technique condition influencing SO2 removal efficiency and desulfurization mechanism.The suitable growth condition of free-Thiobacillus ferrooxidans was studied at first. The results of experiments indicated that bacterium grew well and optimum life-cycle was shorter(about 35h) under the condition: culture temperature 28℃-32℃, initial pH=2.34, inoculum 15%(v/v), culture medium 100mL/250mL(v/v).Immobilization included two steps: inoculated cultivating out of bio-trickling tower and start-up in bio-trickling tower. By comparing the bio-membrane characteristics of three kinds of carriers(coal ash powder ceramic rasching rings and argil particle), it was found that bio-membrane begins to active most rapidly and bio-membrane grow better on argil than on the other two carriers. The experimental results of bio-membrane start-up show that Fe2+ oxidization velocity has good relativity with its absorbency. In addition, the change of pH and pressure loss coincides with lag phase, dynamical growth phase and stabilization phase, and they are the important parameters of bio-membrane stat-up accomplishment.Comparison experiment about SO2 removal performance on different condition was made. The results show that contribution of Thiobacillus ferrooxidans bio-film to SO2 removal is primarily indirect oxidation, and secondary direct oxidation. Because...
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