【作者】 李晓东；

【导师】 魏德洲； 王英刚；

【作者基本信息】 东北大学 ， 矿物加工工程， 2005， 硕士

【摘要】 随着生物催化方法的不断发展,探求技术先进、经济合理的生物脱硫技术已成为烟气脱硫技术研究的热点,开发适合中国国情的烟气脱硫技术势在必行。用氧化亚铁硫杆菌挂膜-脱硫技术结合了无机化学与微生物学原理,能够有效控制大气中SO₂污染。本文对氧化亚铁硫杆菌的游离菌生长和固定化生长的影响因素分别进行了研究,并就进气浓度、进气流速、喷淋率等对脱硫效果的影响进行了系统的试验研究。 试验中首先研究了氧化亚铁硫杆菌游离菌的适宜生长条件,结果表明,在培养温度为28℃、初始pH=2.34、接种量（v/v）10%、培养基加入量（v/v）100mL/250mL时,细菌的活性最佳,生长周期最短,约为36h。 试验分两步挂膜:培养箱预挂膜和滴滤塔中挂膜。在氧化亚铁硫杆菌游离菌的最佳生长条件下进行培养,用拉西环连续接种2个周期后,生物膜开始表现出良好的活性。在培养箱预挂膜过程中,进行了粉煤灰、拉西环、陶土颗粒作为挂膜载体的对比试验,结果表明,陶土颗粒的生物膜活性明显好于其它两种挂膜载体的。滴滤塔中挂膜时,采用陶土颗粒在塔中挂膜3d后,氧化亚铁硫杆菌的游离菌数趋于稳定,膜的固定化完成;5d后Fe²⁺氧化率保持在0.2g·L^-1·h^-1,通入低浓度SO₂气体驯化后,脱硫率可达到99%以上。 脱硫试验在通气浓度低于2000mg/m³时,脱硫率在95%以上,浓度在4000mg/m³以下时,脱硫率在75%以上;在通气浓度为1996mg/m³、气流速度在0.2m/s以下、喷淋率在120以上时,脱硫率达到了95%以上。 由双膜理论可知,脱硫的过程是气膜在起主要作用。催化动力学分析,生物酶催化反应的速度,远大于化学催化的速度。生物膜法以其低能耗,无二次污染等优点,在烟气脱除SO₂方面有着广泛的应用前景。更多还原

【Abstract】 With the development of biology catalyzing, biology desulfurizing technology which is advanced and economical has become a hotspot on the study of flue gas desulfurizing technology, so it is imperative to develop smoke desulfurizing technology suitable to the situation of China. In trickling bio-filter, desulfurizing by Thiobacillus ferrooxidans combined with inorganic chemistry and microbiology elements, sulfur dioxide in flue gas can be removed effectively. The paper has respectively studied factors influencing the growth of free-bacterium and immobilizing bacterium of Thiobacillus ferrooxidans. The factors influnencing desulfurizing rate ,such as SO₂ inlet density ,entry gas velocity and spraying rate, has also been discussed in this paper.The suitable growth condition of free-Thiobacillus ferrooxidans has been found by nephelometery at first. The results of experiments indicated that bacterium grown well and life-cycle was shorter（about 36h） under the condition: culture temperature 28 ℃, initial pH=2.34, inoculum 15%（v/v）, culture medium 100mL/250mL（v/v）.Hanging bio-membrane experiment included two steps: in cultivating box and in trickling bio-filter. When free-Thiobacillus ferrooxidans grown well, bio-membrane began to active rapidly after inoculating two cycle continuously with ceramic rasching rings. During the course of hanging bio-membrane in cultivating box beforehand, bio-membranes were compared with coal ash powder、 ceramic rasching rings and argil particle as carrier respectively. The study indicated that bio-membrane grown better on argil than on the other two carriers. After 3 days’ hanging bio-membrane in trickling bio-filter , the number of free-Thiobacillus ferrooxidans has no change nearly and hanging bio-membrane completed; 5 days later the oxidation rate of Fe²⁺ kept 0.2 g · L^-1 · h^-1, and desulfurizing rate reached more than 99% after domesticating by lower density SO₂ which was pressed into trickling bio-filter.As for desulfurizing experiments, desulfurizing rate is higher than 95% when aerating SO₂ density was less than 2000mg/m3, and dominant 75% when it was less更多还原